IWPMA & EHW · 2013-06-12 · 10 th International Workshop on Piezoelectric Materials and...

th10 International Workshop on Piezoelectric Materials and Applications in Actuatorsth8 Annual Energy Harvesting Workshop

organized by:

supported by:

Institute of Dynamics and Vibration ResearchLeibniz University of Hannover

IWPMA & EHW14.-18.07.2013

-BOOK OF ABSTRACTS--preliminary(2)-

Table of Contents

Ultrasonic Tranducer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6I. Adzerikho : Combined Effect of Low-Frequency High-Intensity Ultrasound and Strepto-

kinase on the Efficiency of Thrombi Destruction . . . . . . . . . . . . . . . . . . . 7P. Bornmann : Self-Sensing Ultrasound Transducer for Cavitation Monitoring . . . . . . . 8P. Bruns : Stress Distribution and Durability of Pre-stressed Piezoelectric Multilayer Actua-

tors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9J. L. I. Domınguez : A Review of Oscillator and Acoustic Wave Devices Based in Piezo-

electric Materials as Viscosity Sensors . . . . . . . . . . . . . . . . . . . . . . . . 10K. Galal : Finite Element Simulation of Ultrasonic Systems With Impact Using ANSYS . . 11Y.-B. Ham : Development of Needle-free Injector for Liquid Drug Delivery . . . . . . . . . 12T. Hemsel : Reliability Analysis of Ultrasonic Power Transducers . . . . . . . . . . . . . . 13J. Hu : Ultrasonic Nano-Manipulations Based on Mobile Acoustic Streaming Field . . . . . 14M. Huang : Model-Based Poling Investigation of Piezoelectric Monolithic Ring Elements in

Circumferential Direction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15M. Huang : Poling and Characterization of Piezoelectric Monolithic Ring Elements for Ultra-

sonic Torsional Transducers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16I. Ille : Observer Based Damping of Overtones Generated by the Nonlinearity of Ultrasonic

Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17D. Kern : Active Strut for High Precision Positioning . . . . . . . . . . . . . . . . . . . . . 18T. Kishi : Condition of Micro Droplet Generation by Using an Ultrasonic Torsional Transducer

and a Micropore with Tapered Nozzle . . . . . . . . . . . . . . . . . . . . . . . . . 19D. Koyama : Optical Lens Array with Variable Focus Length and Pitch Using Acoustic Ra-

diation Force . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20W. Littmann: A New Direction for Ultrasonic Cutting . . . . . . . . . . . . . . . . . . . . . 21T. Maeda : Piezoelectric applications of hydrothermal (K0.48Na0.52)NbO3 ceramics . . . 22S. Mojrzisch : Vibration Frequency Adjustment of Auto-Resonant Ultrasonic Transducers

by Variation of their Output Impedance in Regard to a Switching Converter . . . . . 23S. Mojrzisch : Piezoelectric Driven Mass Actuator for Vibration Control of Drive Chain Vi-

brations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24S. Mojrzisch : Phase Controlled Frequency Response Measurement and Operation of Pie-

zoelectric Systems at High Vibration Amplitudes . . . . . . . . . . . . . . . . . . . 25M. Mutou : Study on Near-Field Acoustic Levitation by Multi-Mode Ultrasonic Transducer . 26K. Nakamura : Non-Contact Mixing and Dispensing of Droplet Using Ultrasonic Levitation 27T. M. Pham : Ultrasonic friction reduction in sealing contacts: Characterization and reaction

of system at loading positions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28Q. He : A Polishing Vibrator Using Bending and Longitudinal Vibration Modes and its Appli-

cations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29K.-A. Saalbach : Bond Quality investigation of Ultrasonic Assisted Composite Casting . . 30A. Struckas : Focusing Piezomechnical Actuators for Acoustic Levitation . . . . . . . . . 31S. Li : Dynamic Reactive Power Compensation for Piezoelectric Actuator Based on Trans-

former . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32H. Tanaka : A Noncontact Pipette for Small Droplet Using Ultrasonic Standing Waves . . . 33P. Vasiljev : Excitation of Elliptical Trajectories in a Langevin Bending Type Transducer . . 34P. Vasiljev : Investigation of Heating Problem in a Langevin Piezoelectric Actuator . . . . 35M. Sborikas : Piezoelectric Cellular Polymers as Sensors or Air-Borne Ultrasonic Transdu-

cer: Property Adjustment by Foam-Structure and Geometry Variations . . . . . . . 36

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Table of Contents

W. Wurpts : Some Aspects on the Dynamics of Ultrasonic Actuators with Impacts . . . . . 37W. Wurpts : Piezoelectric Equivalent Circuits and Finite Element Model Order Reduction . 38W. Wurpts : A transfer matrix method for the design of resonant piezoelectric devices . . . 39C.-C. Yin : Piezoelectric Fiber Composite Acoustic Wave Sensors . . . . . . . . . . . . . 40

Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41R. Bansevicius : Piezoelectric Active Bearings and Supports: Structures, Characteristics,

Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42T. Q. Bui : Extended Finite Element Simulation of Stationary Dynamic Cracks in Functionally

Graded Piezoelectric Solids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43X. Guo : Preparation and Properties of 2-2 Piezoelectric-Damping Composites . . . . . . 44M. Gurbuz : Effect of the Excess PbO on Densification of Electrospray Deposited Pb(Zr0.52Ti0.48)O3

Thick Films . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45M. Gurbuz : Dielectric and Leakage Current Analysis of Li doped NBT-BT Single Crystals 46N. Jackson : Flexible Aluminium Nitride/Polyimide Piezoelectric material for MEMS applica-

tions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47V. Kalem : Effect of PMnN Content on the Electrical Properties and Phase Transition Beha-

viors of [PSLZT]-[PMnN] Ceramics . . . . . . . . . . . . . . . . . . . . . . . . . . 48Y.-S. Lee : Effects of Annealing Temperature and Oxygen Pressure on Electrical Properties

of (Na0.5K0.5)NbO3 − CaTiO3 Films Grown on Pt/T i/SiO2/Si Substrates . . . 49J. Lee : Stress Modulation of Aerosol Deposited PbTiO3 Film for High Temperature Appli-

cations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50S. Lee : Control of Hysteresis in Ferroelectric Materials with Grain Size . . . . . . . . . . . 51S. J. Rupitsch : Simulation Based Approach to Identify Temperature-Dependent Material

Parameters of Piezoceramics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52J. Ryu : Giant Magnetoelectric Characteristics of Ni/PMN-PZT/Ni Laminate Composites and

Anisotropic Crystallographic Effect . . . . . . . . . . . . . . . . . . . . . . . . . . 53J. Ryu : Exceptionally Enhanced Magnetoelectric Properties of PZT Thick Film on Ni Sub-

strate with Oxide Electrode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54N. Setter : Functions and Structures of Ferroic Domain Walls . . . . . . . . . . . . . . . . 55M. Takaoka : Study on Torque Generation of the Ultrasonic Motor using a High-Speed

Microscope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56S. Wada : Piezoelectric Enhancement of Relaxor-based Lead-free Piezoelectric Ceramics

by Complex Nano/Macro Domain Configuration . . . . . . . . . . . . . . . . . . . 57Y. Wang : Research on a Linear Piezoelectric Motor with Double Driving Elements . . . . 58J. Wang : The Contact Problem of Hard Contact Materials Linear Ultrasonic Motors . . . . 59H. B. Xu : Structural and Piezoelectric Properties of the (Na1−xKx)NbO3 Nanorods Syn-

thesized by Hydrothermal Method . . . . . . . . . . . . . . . . . . . . . . . . . . . 60D. Yamaguchi : Evaluation of Piezoelectric Materials for Transducer at Ultralow Temperature 61Z. Yao : Design method and research progress on linear ultrasonic motors . . . . . . . . . 62

Ultrasonic Tranducer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63C. Chen : A Novel Linear Ultrasonic Motor Based on Shear Vibration Mode . . . . . . . . 64T. Cheng : Proposal and Development of Ultrasonic Locking Mechanism . . . . . . . . . . 65F. Fang : Phase Fragility and Mechatronic Reliability for Pb(Mg1/3Nb2/3)O3 − PbT iO3

Ferroelectric Single Crystals at the Morphotropic Phase Boundary . . . . . . . . . 66Y. Fujiuchi : Domain Orientation Controlled KN Family Piezoelectric Materials with Hydro-

thermal Powders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67W. Huang : Research on an S-shape Linear Piezoelectric Motor . . . . . . . . . . . . . . 68M. Hunstig : High-Velocity Slip-Slip Operation of Piezoelectric Inertia Motors -Experimental

Validation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69H.-W. Kang : Multi-layered Piezoelectric Earthworm Type Actuator . . . . . . . . . . . . . 70R. Kashima : Design of a Junction in Noncontact Ultrasonic Transportation System . . . . 71F. Li : Ultrahigh Superelastic and Actuation Strains in BaTiO3 Crystals by Reversible Elec-

tromechanical Domain Switching . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

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Table of Contents

Y. Shi : Linear Piezoelectric Actuator for Precision Linear Positioning . . . . . . . . . . . . 73E. Teidelt : Nano-Positioning Stick-Slip Motors: Numerical Simulation and Performance Im-

provements Using the Method of Reduction of Dimensionality . . . . . . . . . . . . 74D. O. Uribe : Piezoelectric Tactile Sensor using Multisine Excitation for Differentiation of

Biological Tissues and Phantoms . . . . . . . . . . . . . . . . . . . . . . . . . . . 75L. Wang : A Piezoelectric Tracked Vehicle with Potential Application to Planetary Exploration 76L. Yang : Flexible Supporting and Fixing Method for Hybrid Ultrasonic Motor Using Longitu-

dinal and Torsional Vibration Modes . . . . . . . . . . . . . . . . . . . . . . . . . . 77Energie Harvesting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

A. Affanni : Low-Power Energy Harvesting Solutions for Wiegand Transducers . . . . . . 79W. Al-Ashtari : Characteristics of Piezoelectric Harvesters in Autonomous Systems . . . . 80K. H. Baek : Study on Energy Storage Device for the Impact-Based Piezoelectric Energy

Harvesting System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81Y. Bai : Fabrication and Investigation of Free-standing Piezoelectric Thick-film Cantilevers

for Energy Harvesting Applications . . . . . . . . . . . . . . . . . . . . . . . . . . 82S. Bengsch : Wet Chemical Etching of PZT (Lead-Zirconate-Titanate) . . . . . . . . . . . 83S. Bengsch : Analysis of a Precision-Engineered Electro-Magnetic Energy Transformer . 84J.-J. Choi : (La, Sr)(Ga,Mg)O3− δ Electrolyte-based SOFC by Aerosol Deposition . . . 85S. Chun-Hua : Arrayed Piezoelectric Unit Design for Harvesting Pavement Vibration Energy 86A. Feldhoff : Thermoelectric Properties of Some Mixed Ionic and Electronic Conducting

Oxides . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87H. Salleh : Design and Implementation of the Wideband Tunable PZT Energy Harvester in

Power Generation Plant in Malaysia . . . . . . . . . . . . . . . . . . . . . . . . . . 88E. Heffel : Friction Induced Vibrations for Energy Harvesting Applications . . . . . . . . . 89S. Hidaka : Pin Structured Substrate Design for Piezoelectric Ceramic Material . . . . . . 90S. K. Hong : Improved Characteristics of Piezoelectric Energy Harvesting System with

Change of Total Stiffness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91J. Hur : Piezoelectric Properties (1−x)Pb(Zr0.47Ti0.53)O3−xPb[(Zn0.4Ni0.6)1/3Nb2/3]O3

Ceramics and the Output Power Density of the Energy Harvesters . . . . . . . . . 92S. Ideyama : Piezoelectric Generator Using Impact Induced Vibration . . . . . . . . . . . 93W.-S. Jung : Embossed PZT Thin Film Piezoelectric Energy Harvester . . . . . . . . . . . 94M. Jahn : Energy Harvesting Using Magnetic Shape Memory Alloys . . . . . . . . . . . . 95C. Jianyu : An Explicit Multi-Grid Algorithm to the Air Intake Annulus of the Airflow Resonant

Piezoelectric Generator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96H. J. Jung : Study on Increasing Current for Hitting Type of Piezoelectric Energy Harvesting

System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97H.-W. Kang : Piezoelectric Energy Harvester Using Shear Mode . . . . . . . . . . . . . . 98M.-G. Kang : Oxide Semiconductors Embedded on Polymer Films for Flexible Piezoelectric

Energy Harvesting System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99C. V. Karadag : A Piezoelectric Cantilever Beam with Tunable Natural Frequency . . . . . 100J. H. Kim : Effect on Hitting-Typed Piezoelectric Energy Harvesting System with the Area of

Hit Piezoelectric Device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101S. B. Kim : Study of Optimizing Acceleration Distribution on Time-Varying with Equal Input

Energy in Piezoelectric Energy Harvesting . . . . . . . . . . . . . . . . . . . . . . 102C. Kim : Optimum Design of Cantilevered Energy Harvesters with Piezoelectric Materials

and Vortex Shedding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103M. Kroener : A Multi-Source, Microcontroller Based Energy Management System With off-

the-shelf Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104K. Kumar : CHEW: A Compact Harvesting - Energy Windbelt . . . . . . . . . . . . . . . . 105J.-T. Lin : Low Frequency Energy Harvesting From Coupled Rolling Magnet Spheres . . . 106W. Q. Liu : Optimization of a Bistable Piezoelectric Harvester for Wideband Vibration Energy

Harvesting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107J. W. Moon : Multi Piezoelectric Array Energy Harvesting System for Watt Level Power . . 108

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L. Mateu : Maximizing the Output Power of a Piezoelectric Generator from the AdmittanceMeasurement by selecting the Rectification Technique . . . . . . . . . . . . . . . . 109

S. Ravi : Numerical Modelling of Piezoelectric Energy Harvesting Devices Driven by FlowInduced Vibrations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110

B. Ren : Investigation of Piezoelectric Energy Harvesters Based on Relaxor-Based SingleCrystals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111

J. Ryu : Magnetoelectric Benders with Piezoelectric Single Crystal and MagnetostrictiveMetal for Energy Harvesting from Mechanical Vibration and Electromagnetic Wave 112

R. Salloum : Tuning of a Vibration Absorber with Shunted Piezoelectric Transducers . . . 113D. O. Solovyeva : Purple Membranes as Promising Biomaterial for Photovoltaic Devices . 114T. Ware : Softening Electronics For in Vivo Energy Harvesting Applications . . . . . . . . 115M. S. Woo : Relationship Between Current and Impedance in Piezoelectric Energy Harves-

ting System for Water Waves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116Y. Yang : Design of Small Piezoelectric Windmills for Different Load Types and Working

Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117T. Yang : Broadband Piezoelectric Energy Harvesting Using Piezoelectric Array . . . . . . 118C. H. Yang : Study on Piezoelectric Energy Harvesting System for Applying Vibration of

Commercial Trains in Korea . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119S. Y. Zaitsev : Hybrid Materials Based on Photosensitive Membrane Proteins for Energy

Conversion Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120H. Zessin : Modeling of Hybrid Piezoelectrodynamic Generators . . . . . . . . . . . . . . 121C. L. Zhang : Magnetoelectric Effects in Functionally Graded Multiferroic Bilayers . . . . . 122H. Zou : Simulation Analysis of the Piezoelectric Microgenerator from Vibration induced by

Acoustic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123

Table of Contents

Ultrasonic Tranducer

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I. Adzerikho : Combined Effect of Low-Frequency High-Intensity Ultrasound andStreptokinase on the Efficiency of Thrombi Destruction

Author: I. Adzerikho1, A.Bubulis2, V.Jurenas2, V.Minchenya3, V.Veikutis41 Belarusian Medical Academy of Post-Graduate Education (Republic of Belarus)2 Kaunas University of Technology (Lithuania)3 Belarusian National Technical University (Republic of Belarus)4 Institute of Cardiology (Lithuania)

E-Mail: [email protected]: ultrasound system, piezoelectric transducer, medicamentous fibrinolysis

Results of various experimental studies indicatethat low-intensity ultrasound (US) intensifies the me-dicamentous fibrinolysis. At the same time, on theopinion of Hong and co-authors, as well as otherresearchers, high-intensity US is not recommendedto be used in combination with thrombolytic agentsdue to the transience of exposure of thrombus to USand relatively low speed of the enzymatic process.It is our hypothesis that high-intensity low-frequencyUS can accelerate the medicamentous fibrinolysis.During in vitro studies, we showed that the adminis-tration of streptokinase (SK) prevents the formationof particle conglomerates resulting due to destructi-on of fibrin clots using low-frequency high-intensity

US. In addition, it was established that in conditionsof the combined effect of streptokinase and high-intensity US, the process of acoustic-mechanicaldestruction of thrombus is prevailing, and the fibri-nolytic effect of streptokinase is generally witnessedafter the termination of US and manifests itself in en-zymatic lysis of both resultant particles and residualclot mass.In this study we have analyzed the effect of low-frequency high-intensity US on the dynamics of fi-brinolysis induced by SK, model thrombi of variousstructure, and characteristic features of the fibrin clotnetwork structure occurring during the combined ef-fect of US and SK.

Curriculum Vitae:

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Table of Contents

P. Bornmann : Self-Sensing Ultrasound Transducer for Cavitation Monitoring

Author: Peter Bornmann1, Takafumi Maeda2, Tobias Hemsel1, Takeshi Morita2, Walter Sextro1

University of Paderborn (Germany)Graduate School of Frontier Sciences (Japan)E-Mail: [email protected]: Cavitation Detection, Cavitation Monitoring, Ultrasound Transducer, Self-Sensing

In sonochemistry chemical reactions are initiatedor enhanced by acoustic cavitation.

To be able to find optimal parameters for sono-chemical processes and to monitor these parame-ters during operation, feasible measurement techni-ques are required. While the chemical compositionof the liquid, temperature and pressure are usuallyeasily accessible parameters, there is no accreditedmethod for direct cavitation measurements. For thisreason it is necessary to find accessible parametersthat indicate the occurrence of cavitation and ideallycorrelate to the strength of cavitation.

While some cavitation detection methods arenot applicable for measurements throughout so-nochemical processes (e.g. aluminium foil erosi-on test), the detection of acoustic cavitation noi-se, obtained by pressure sensors in the liquid, isa candidate for cavitation monitoring. But as clo-sed systems and harsh process conditions like hightemperature, high pressure and aggressive liquidscomplicate or prevent the application of sensors inthe liquid, alternative detection methods are desi-red.

In a previous study the applicability for cavitati-on monitoring of an external microphone and of aself-sensing ultrasound transducer could be shown.While external microphones are problematic in noi-sy industrial environment, the most suitable wayfor cavitation monitoring is to utilize the ultrasoundtransducer itself as a sensor. The transducer is notaffected by ambient noise and no additional sensorsare required; thus this method could be applied toany existing system with direct ultrasound irradiati-on.

In this contribution the influence of the transdu-cer design on the applicability for cavitation monito-ring is considered to analyze the applicability of thismethod for various ultrasound systems. First, app-licable indicators for cavitation detection are identi-fied experimentally by comparison to other cavita-tion detection techniques. Second, the influence ofthe design of transducers on the obtainable signalsis analyzed. Finally, a system with a self-sensing ul-trasound transducer is set up and tested in a closedsystem under high pressure and temperature.

Curriculum Vitae: Date of Birth: 24.8.1981 Education:2002 - 2008: Academic Studies of Mechanical Engineering, Major: Product Design, at the Uni-versity of Paderborn Since 2008:Research Assistant at the Chair of Mechatronics and Dynamicsat the University of Paderborn Research Interests:

• Applications of Ultrasound

• Ultrasound-Assisted Production of Led-Free Piezoelectric Materials

• Structural Dynamics and Acoustics

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P. Bruns : Stress Distribution and Durability of Pre-stressed Piezoelectric MultilayerActuators

Author: Peter Bruns, Sebastian Mojrzisch, Jens TwiefelLeibniz Universitat Hannover (Germany)E-Mail: [email protected]: Pre-stressing of piezoelectric multilayer actuators, Lifetime of piezoelectric multilayeractuators

Pre-stressing piezoelectric multilayer actuatorsoffers optimized operation and thus positive ef-fects on actuator lifetime. Actually, pre-stressing ofthe piezoelectric actuators is indispensable for nu-merous applications. Additional pre-stressing com-ponents though can lead to significant decrease ofsystem resonance frequency as well as increase ofactuator volume. To avoid these negative effects anovel pre-stressing method has been developed atthe Institute of Dynamics and Vibration Research(Patent no.: WO002012122975A2). Yet appropriateexamination of stress distribution as well as durabi-lity due to an asymmetrical or eccentric assemblyof the new pre-stressing method are required sincepiezoelectric multilayer actuators are very sensitiveto torsion and bending loads.For this purpose non-ideal pre-stressing configurati-

ons are simulated and discussed in this paper. Ana-lysis and comparison of non-constant pre-stressingforce, eccentric position of piezoelectric actuatorand superposition of these two cases are carriedout. The resultant tensions occurring in the piezo-electric material are examined and discussed. It isshown that slight asymmetries yet lead to signifi-cant loads and thus should be avoided. Furthermo-re, explicit effects on actuator lifetime in dependen-cy of non-ideal pre-stressing as well as the surroun-ding medium are analyzed and discussed. Identifi-cation of an optimized pre-stressing apparatus andenvironmental conditions considering the results ofsimulation and measurement respectively concludethe paper.Detailed equations, simulations and measurementswill be given in the final contribution.

Curriculum Vitae:

• 2004 - 2009 B.Sc. in Mechatronics at the Leibniz Universitat Hannover

• 2009 - 2011 M.Sc. in Mechatronics at the Leibniz Universitat Hannover

• Since 2011 Ph.D. Student at the Institute of Dynamics and Vibration Research

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Table of Contents

J. L. I. Domınguez : A Review of Oscillator and Acoustic Wave Devices Based inPiezoelectric Materials as Viscosity Sensors

Author: Juan L. Ibarra Domınguez, Gustavo A. Lara Saenz, Jose Mireles Jr. Garcia, RobertoC. AmbrosioUniversidad Autonoma de Ciudad Juarez (Mexico)E-Mail: [email protected]: Viscosity sensors, piezoelectric, MEMS oscillators, Acoustic Wave Devices

The viscosity property of liquids has been fullystudied, capillary tubes and rotational systems arethe most commonly used for reference and mea-surements in laboratories. However there is still in-terest to reduce measurement time and volume ofsample measurements, as well as to simplify proce-dures as portable systems come to market demandand Oscillators and Vibration devices has been re-ported as good candidates to attend these deman-ds, Oscillator MEMS devices require only 5uL samp-les and measurement is completed in only 20ms.But these devices have problems due to includingmobile parts and is not often possible to use themfor fluid testing. Among these candidates are theacoustic wave devices (AWD), classified into the vi-bration category. Using piezoelectric properties of

AWD and electrostatic input signals, the output si-gnal characteristics are related with the liquid pro-perties, in addition AWD could be made of solid-state and can be used in fluid environment; howeverthe sensor response is a function of different proper-ties such as: viscosity, density, electrical conductivi-ty, and it is complicate to isolate one to the other.In order to concentrate the most important informa-tion about this topic for future research, this workpresents a review of techniques used for viscositymeasurements, focusing mainly on oscillator devi-ces and acoustic wave devices using piezoelectricmaterials and MEMS technology. Discussion aboutadvantage and disadvantage and the limits and sco-pes for each technique are presented.

Curriculum Vitae:

10


K. Galal : Finite Element Simulation of Ultrasonic Systems With Impact Using ANSYS

Author: Kerim Galal, Wiebold WurptsLeibniz Universitat Hannover (Germany)E-Mail: [email protected], [email protected]: Ultrasonic, vibro-impact, autoresonant, Ansys, Newmark

In many ultrasonic applications the energy is in-troduced into an ultrasonic process through impactimpulses. Intermittent contact situations are a strongnonlinearity and influence the system behavior. The-refore they affect the stress profile and require re-cent attention. In this contribution the transient re-sponse of an ultrasonic tool with impact is investi-gated using FE analysis. The objective of this rese-arch is to simulate a realistic working condition of avibro impact tool using ANSYS. Under working con-dition the contact increases the stiffness and accor-dingly the natural frequencies of the ultrasonic tool.Furthermore it lifts the at-rest position of the non-linear oscillations. In a first part the time integrati-on scheme in ANSYS is generally addressed. Theaccuracy and stability of the Newmark method forimpact situations is discussed and compared withanalytical solutions of an elementary model. Follo-wing an ultrasonic vibro impact tool is investigatedemploying a transient analysis with sinusoidal volta-

ge excitations on the piezoelectric material. The lon-gitudinal vibration shape of the tool consists of threehalf-wavelengths introduced by the converter, boos-ter and the horn. The tool is mounted with spring-damper-combinations on the circumferential nodesin the middle of the booster part. The contact sur-faces are between the horn and the anvil, which isalthough mounted with spring-damper-combination.The contact is enforced with an additional pressingforce, which is applied on the lower surface of theanvil. For the external voltage excitation a fixed fre-quency is chosen and hence the results dependstrongly on the excitation frequency. In order to gua-rantee resonance even under nonlinear conditionsthe autoresonant excitation is discussed as well.Hereby the current of the piezoelectric elements isfiltered using MATLAB and afterwards fed back onthe input voltage at every time-step. The contributionconcludes with a comparison between the differentexcitation mechanisms.

Curriculum Vitae: 10/15/2009 - 02/28/2011 Research Assistant at the Institute of Production Engineering andMachine Tools (IFW Hannover)

• Machining of indexable inserts at Wendt WAC 715 Centro

Since 2012 Research work at the Institute of Dynamics and Vibration Research within student project thesis

• Modal and Harmonic Analysis in Ansys Classic

• High Frequency Transient Analysis of Ultrasonic Sonotrode in Contact - Ansys Classic

07/01/2012 - 11/30/2012 Research assistant at the Institute of Dynamics and Vibration Research (IDS Hannover)

• Transient Contact Analysis of Piezoelectric Bending Generators in ANSYS Classic

07/02/2007 - 08/31/2008 Production worker at AutoVision GmbH (Volkswagen AG)09/03/2007 - 05/31/2000 Volunteer Community service in Youth Center in Letter, Germany06/02/2008 - 09/05/2008 Internship (10 weeks) at Stahl- und Metallbau Ihnen GmbHSince 01/01/2010 Founder of YoungFEMTechServices:

• Finite-Element Modeling in Femap with NX Nastran V10

• Static analysis and cycle fatigue strength verification

• Post-Processing in Mathworks Matlab

2010 - 2011 Projects as a Freelancer for Engineering Office Pihl-Expert

• Finite-Element Modeling and static strength verification of foundation structures of offshore wind turbines

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Y.-B. Ham : Development of Needle-free Injector for Liquid Drug Delivery

Author: Young-Bog Ham1, Eun-Joo Lee2, Sung-Jin Oh1, Gi-Tae Lee1, In-Seob Park1, Hyo-JinHan3

Korea Institute of Machinery & Materials (South Korea)Woosong University (South Korea)Hantec (South Korea)E-Mail: [email protected]:Jet injector, Needle-free injection, Piezoelectric valve, High pressure pump, Single nozzle injector

The purpose of this study is to design a jet in-jector for needle-free liquid injection into the skin ofagricultural animals that can be a simple, lightweightand semi-permanent, for the delivery of proteinsor vaccines. Jet injectors, which deliver drugs intothe skin using compressed springs or compressedgas, provide a needle-free method of conventionaltransdermal drug delivery. However, the compres-sed spring or gas type injector has the drawbacks ofhigh weight and impact noise. The other hand, thedispensing device using high pressure pump andpiezoelectric valve has the advantage that is smaller

than the spring or gas injectors. Therefore, we pro-pose a mechanism that consists of a high pressurepump, an accumulator, a piezoelectric valve and asingle nozzle. To determine specifications, we tes-ted the Acushot injection - a compressed gas injec-tion - and used it as our benchmark. The pressure,liquid drug quantity and force of the liquid injectionexperiments were measured with the fabricated de-vices. Finally, the model of jet injector we neededwas decided as the result of analysis and comparedwith Acushot and developed injectors.

Curriculum Vitae:

12


T. Hemsel : Reliability Analysis of Ultrasonic Power Transducers

Author: Tobias Hemsel1,Peter Bornmann1, Takeshi Morita2, Christoph Sondermann-Wolke1,Walter Sextro1

1 University of Paderborn (Germany)2 The University of Tokyo (Japan)

E-Mail: [email protected]@upb.deKeywords: ultrasonic power transducers

Ultrasonic transducers are used in many indus-trial applications such as plastics or metal welding,bonding, machining, cutting, cleaning or chemicalprocesses. During the setup of new devices or usingstandard equipment in uncommon environment (e.g. high humidity or temperature) it might happen thatthe transducers unexpectedly fail instantly or aftersome time of use. Often, such difficulties are solvedempirically by trying other transducers, improvedmanufacturing technologies or changing driving pa-rameters and boundary conditions (encapsulating,external cooling, etc.). This evidently leads to incre-ased development or operating costs and someti-mes deficient performance of the overall system.

While reliability has been studied worldwide in-tensively in the case of piezoelectric multilayer ac-tuators - driven by car industry which now uses suchactuators in their fuel injection systems - nearly noliterature is available for the reliability of ultrasonicpower transducers. As well, manufacturers seldom

present data about ageing or lifetime of their com-ponents. To enhance the knowledge about typicalfailure mechanisms of ultrasonic power transducersunder different load conditions, our contribution - asa first step - reports on a theoretical study on thereliability of common known ultrasonic transducersfor different applications.

Resulting from structural and function analysis ofdiverse ultrasonic power transducers together withtheir application and control, different possible er-rors and their impact on the overall system behaviorare described in detail. Based on this Failure Modeand Effect Analysis (FMEA), it is proposed which ty-pe of construction is preferable for different applicati-ons and boundary conditions. Hints are given how toavoid failures by construction, control or other mea-sures. As well - if failures are inavoidable such asthose belonging to overstraining, wear and tear orfatigue - methods to detect or forecast failures arediscussed.

Curriculum Vitae: Dr.-Ing. Tobias Hemsel, born in 1970, studied mechanical engineering witha concentration in engineering design from 1990 to 1996 at the University of Paderborn. In thefollowing years, between 1996 and 2001, he worked as a research assistant for Prof. Dr.-Ing. JorgWallaschek at the Chair of Mechatronics and Dynamics. In 2001, he recieved his PhD with honorsand was given a permanent position with the chair as an academic supervisor. In both 2003 andagain in 2005, he was awarded with the Research Award from the University of Paderborn. AfterProf. Wallaschek left the University of Paderborn in April 2007, he was acting head of the chairuntil Prof. Sextro commenced his duties in March 2009. From February to March 2009, TobiasHemsel was a ’Visiting Professor’ at the University of Tokio. He has published more than 60papers.

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J. Hu : Ultrasonic Nano-Manipulations Based on Mobile Acoustic Streaming Field

Author: Junhui HuNanjing University of Aeronautics and AstronauticsE-Mail: [email protected]@nuaa.edu.cnKeywords: acoustic nano-manipulation

Acoustic manipulation technology has the advan-tages such as less heat damage to samples (forsome operating principles), no selectivity to sam-ple material, and simple device structures. Conven-tional acoustic manipulation technology uses theacoustic radiation force to trap micro particles. Ho-wever, it is difficult to use the acoustic radiation forceto stably manipulate a nanoscale entity because theacoustic radiation force on such an entity is muchless than the force caused by the acoustic strea-ming, which usually flushes the nanoscale entityaway.

We demonstrate a strategy of acoustic nano-manipulation, which utilizes mobile acoustic stre-aming fields. The manipulators based on this prin-ciple, can effectively suck, align, contact and non-contact trap, 3D and 2D transfer and rotary drive

an individual nanowire in a water suspension filmon substrate surface, and can concentrate and ra-dially align nanowires in a water suspension filmon substrate surface. These manipulations are im-plemented by using various ultrasonic micro-probeswith different shapes and vibration modes. The stra-tegy has the functions of controlling the orientation,trapping position and rotary center of the manipula-ted nanowire. Our experiments are conducted underan optical microscope; silver nanowires used in thesuspension are about 100 nm thick and several tento more than one hundred microns long; the opera-ting frequency is less than 200 kHz.

The proposed manipulation technology has po-tential applications in the assembling of nano/microstructures, measurement of nano/micro scale mate-rials and high sensitivity sensing.

Curriculum Vitae: Junhui Hu received his Ph.D. Degree from Tokyo Institute of Technology, Tokyo,Japan, in 1997, and B. E. and M. E. degrees in electrical engineering from Zhejiang University,Hangzhou, China, in 1986 and 1989, respectively. He is a Chang-Jiang Distinguished Profes-sor of the Ministry of Education of China, director of Precision Driving Lab at Nanjing Universityof Aeronautics and Astronautics (NUAA), and deputy director of State Key Laboratory of Me-chanics and Control of Mechanical Structures, China. Dr. Hu was a research engineer at theR&D Center of NEC-Tokin, Sendai, Japan, from Nov. 1997 to Feb. 1999; research fellow andpostdoctoral fellow at Hong Kong Polytechnic University, Hong Kong, China, from 1999 to 2001;assistant professor at Nanyang Technological University, Singapore, from 2001 to 2005; and as-sociate professor at the School of Electrical and Electronic Engineering, Nanyang TechnologicalUniversity, Singapore, from 2005 to 2010. His present research interest includes ultrasonic mani-pulators and actuators, piezoelectric transducers and transformers, physical effects of ultrasound,wireless drive of piezoelectric components, energy harvesting from oscillation, and other novelutilization of vibration. Dr. Hu won the Paper Prize from the Institute of Electronics, Informationand Communication Engineers (Japan) as a first author in 1998, and was awarded the title of va-lued reviewer of Sensors and Actuators A: Physical and Ultrasonics. He has given six invited talksin international conferences, and is the honorary chairman of IWPMA 2011, held in USA. He isthe author and co-author of more than 180 papers (including more than 50 full papers publishedin SCI international journals) and disclosed patents, and a senior member of IEEE.

14


M. Huang : Model-Based Poling Investigation of Piezoelectric Monolithic Ring Elementsin Circumferential Direction

Author: Minghui Huang, Jens Twiefel, Jorg WallaschekLeibniz Universitat Hannover (Germany)E-Mail: [email protected]: Ultrasonic torsional transducers

Ultrasonic torsional transducers exhibit big poten-tial in many engineering fields. Piezoelectric mono-lithic ring elements poled in circumferential directioncan be employed as the key component to manu-facture high-power ultrasonic torsional transducers.However, this kind of elements demands a diffi-cult poling process and has not been commerciallyavailable at present.

This study aims at the modeling and simulationof the poling process of piezoelectric monolithic ringelements in circumferential direction. As is com-monly known, as-fired piezoelectric ceramics canobtain piezoelectric properties by a poling processwhich involves the application of an electric fieldat elevated temperature. This poling process is in-trinsically a combination of several conditions, in-cluding element composition, applied field strength,poling time, poling temperature etc. Therefore, bysetting appropriate poling conditions, an element

can achieve adequate piezoelectric properties for acertain envisioned application.

In particular, the poling pattern is an interestingfeature in the process of poling a monolithic ring ele-ment in circumferential direction. In the study, twopoling patterns are employed: a fan-shape and aparallel-shape electrode configuration. First the pre-liminary calculations are briefly performed in termsof breakdown field strength and poling efficiencyof the two poling patterns. Then an Ansys finiteelement model, developed to investigate two po-ling patterns is discussed. By defining domain re-orientation rules, the model can simulate the po-ling status for various parameters including elec-tric field strength, geometrical parameters and em-ployed electrode configurations. Hence, an appro-priate poling pattern and optimized applicable fieldstrength are determined.

Curriculum Vitae:

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M. Huang : Poling and Characterization of Piezoelectric Monolithic Ring Elements forUltrasonic Torsional Transducers

Author: Minghui Huang, Jens Twiefel, Jorg WallaschekLeibniz Universitat Hannover (Germany)E-Mail: [email protected]: Ultrasonic torsional transducers

Ultrasonic torsional transducers have big applica-tion perspectives in many engineering fields due totheir motion in tangential direction. However, as keycomponent, suitable poled piezoelectric elementsare hardly available on the market. At present theassembled torsional transducers are either with bulkdesign or employ expensive customized prototypes.This limits the further development of ultrasonic tor-sional transducers in a wider scope.

This study aims at the poling of piezoelectric mo-nolithic ring elements with polarization in circumfe-rential direction to achieve adequate torsional out-put. It is a necessary first step for the application oftorsional transducers by combing increased perfor-mance and compact design at a reduced price.

In the study the piezoelectric ring elements arepoled using the properly designed experimental se-tup with a data acquisition system. Two differentpatterns are employed, which are fan-shaped andparallel-shaped electrode configurations respective-ly. The applied electric field strength as well as opti-

mized poling time and temperature are investigatedin a preliminary investigation.

These poled ring elements are characterized byquasi-static measurements and dynamic measure-ments to evaluate the obtained piezoelectric proper-ties. Vital parameters such as equivalent d15, effec-tive coupling factor keff and mechanical quality fac-tor Qm are measured and evaluated. A commercial-ly available customized prototype is utilized as a re-ference. A torsional transducer prototype is assem-bled using these poled ring elements to investigatetheir application perspectives. The results demons-trate that the poled ring elements exhibit higher me-chanical quality factor Qm and higher electrical ad-mittance than the reference prototypes. The poledring elements also generate adequate torsional de-formation on the transducer prototype and exhibitreasonably good performances under an applicati-on of axial preloads up to 70 MPa. These poled ringelements present promising perspectives for manu-facturing compact and cost-efficient torsional trans-ducers in the future.

Curriculum Vitae:

16


I. Ille : Observer Based Damping of Overtones Generated by the Nonlinearity ofUltrasonic Systems

Author: Igor Ille,Leibniz Universitat Hannover (Germany)E-Mail: [email protected]: piezoelectric transducers, discrete Lunberger observer, nonlinear

At high vibration amplitudes piezoelectric trans-ducers exhibit strong non linear characteristics. Theresult is a resonance frequency shift and the occur-rence of the jump phenomenon. This nonlinear be-havior can also be described by a discrete spectrumof overtones. The jump penomenon causes in cer-tain circumstances a collapse of the vibration am-plitude in foreign excited systems. One approachto elimenate the jump phenomenon is to damp theovertones caused by nonlinear characteristics of a

given piezoelectric system. This paper gives a theo-retical and experimental study of identifkation anddamping of higher harmonics using a discrete Lun-berger observer. The Lunberger observer uses a li-near modell consisting of the fundamental and hig-her harmonic frequencies to detect the present cur-rent of every higher harmonic content. The differentcurrent states are used to generate inversely pha-sed signals to suppress the overtones. Simulationand experimental results are given by this paper.

Curriculum Vitae: Igor Ille received his diploma in mechanical engineering from the Leibniz Uni-versity of Hannover in 2012 and now works as research assistant on ultrasonic systems. Themain issue of his work is parameter identification and feedback control of linear and non linearpiezoelectric systems.

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D. Kern : Active Strut for High Precision Positioning

Author: Dominik Kern, Wolfgang SeemannKarlsruher Institut fur Technologie (Germany)E-Mail: [email protected]: high precision, parallel kinematics

In mechanisms for large ranges with high preci-sion, e.g. in a positioning table realized by paral-lel kinematics, typically the tradeoff arises betweenlarge-range drives with low precision and high pre-cision actuators with only limited stroke. In order tomerge the advantages and eliminate the disadvan-tages both actuators are used in redundant axesand their activation split into coarse and fine posi-tioning. Such a fine positioning may be implemen-ted by active struts as proposed in this contribution.The active strut is comprised of a pre-stressed piezostack actuator in an elastic housing. The housing isdesigned to be rigid versus bending and transversalforces. At the same time its length can be changedby the actuator. After introducing the design in the

presentation it will be demonstrated how the activestrut affects the mechanism and which profits thisbrings for increasing the precision. In the conside-red example of a Biglide-type Mechanism it will beshown how the actuation influences the mechanismand what kind and extent of errors can be compen-sated. Further, different control concepts are tes-ted and evaluated in order to coordinate the controlof the redundant axes. Finally, an additional speci-al feature is outlined, the superposition of a high-frequency excitation and the low frequency actua-tion signal. The high frequency excitation may beused to influence the friction parameters of adjacentjoints.

Curriculum Vitae: 1985: Diploma Mechanical Engineering, University Karlsruhe1987-1992: Research Assistant, Chair for Engineering Mechanics, University Karlsruhe1991: PhD in Mechanical Engineering1992-1997: Research Assistant, Chair for Engineering Mechanics, University Darmstadt1998-2003: Professor for Maschine Dynamics, University KaiserslauternSince 2003: Ordinarius for Engineering Mechanics, Chair for Engineering Mechanics - Dyna-mics/Mechatronics, University Karlsruhe Giving lectures about Multi Body Dynamics, ControlSystems, Mechatronics Reviewer for Journals about Vibrations, Multi Body Dynamics, Micro Sys-tem theory and others.

18


T. Kishi : Condition of Micro Droplet Generation by Using an Ultrasonic TorsionalTransducer and a Micropore with Tapered Nozzle

Author: Toru Kishi, Takuji Murakami, Yusuke Kiyama, Takefumi Kanda, Koichi SuzumoriOkayama University (Japan)E-Mail: [email protected]: Droplet, Ultrasonic transducer, Torsional transducer, Micropore

A generation of small droplets in various liquidsis an important subject. In this study, we have ge-nerated droplets by using a torsional bolt-clampedLangevin-type transducer and the micropore plate.By using the torsional vibration mode, a microporethat is placed at the same distance from the cen-ter is oscillated equally and multiple micropores canbe used. By using the micropore plate which hasmultiple micropores, the torsional mode vibrator cangenerate many droplets.

Firstly, we set out to generate droplet using liquidswhich have low surface tension. We have designedthe micropore plate which has tapered nozzle todecrease the dependence of wettability. The dia-meter of the micropore and the flection angle ofthe tapered nozzle are 50 µm and 25degrees. Wehave evaluated the micropore shape effect againstdroplets generation. The micropore with a tapered

nozzle prevented liquid from spreading around themicropore. As a result, we have succeeded in ge-nerating liquid column using the micropore with thetapered nozzle and silicone oil.

In addition, we generate droplets by using a tor-sional bolt-clamped Langevin-type transducer andthe micropore plate. When the resonance frequencyand the applied pressure were 32kHz and 0.05MPa,the average diameter of droplets and the standarddeviation of the diameter were 83.2 µm and 1.20,respectively. They can generate monodisperse dro-plets regardless of the applied air pressure and theviscosity of liquid. We have evaluated the relation-ship between the droplet diameter and some valueswhich affect droplet formation. We have confirmedthat the droplet diameter can be estimated from thedroplet velocity, the driving frequency and the radiusof liquid column.

Curriculum Vitae: He received his B. Eng. from Okayama University, in Japan in 2012. Sincethen, he has been a master student at the same university. His current research interests are inpiezoelectric actuators and mechatronics.

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D. Koyama : Optical Lens Array with Variable Focus Length and Pitch Using AcousticRadiation Force

Author: Daisuke Koyama1, Megumi Hatanaka1, Kentaro Nakamura2, Mami Matsukawa1

1 Doshisha University (Japan)2 4Tokyo Institute of Technology (Japan)

E-Mail: [email protected]: optical lens, flexural vibrations

An optical lens array whose focal length and lenspitch can be varied by acoustic radiation force wasinvestigated. The lens has no mechanical movingparts and a simple structure that consists of a glassplate (50x50x1 mm3), four ultrasound PZT trans-ducers (10x10x1 mm3), and a 300 − µm-thick si-licone gel film. A lens array can be formed on thesurface of the gel by generating acoustic radiationforce through lattice flexural vibrations of the glassplate. The configuration of the lens was determi-ned through the calculated results by finite elementanalysis. The lattice flexural vibration modes gene-rated at frequencies of 90 and 170 kHz were usedin the prototype, and 21 and 37 lenses were formedamong the four transducers at theses frequencies,respectively. The lens pitch corresponds to half thewavelength of the lattice flexural vibrations. Flexu-ral vibrations with a shorter wavelength (higher fre-

quency) produce a lens array with a smaller pitch;lens pitches of 10 and 7.4 mm were obtained at fre-quencies of 90 and 170 kHz, respectively. The lenspitch could be altered discretely by changing the dri-ving frequency. The lens height decreased graduallywith increasing distance from the center of the glassplate since the vibration amplitude at the center ofthe glass plate being larger than that at the edge.The distribution of light transmitted through the lensarray was calculated by ray tracing. When the in-put voltages were 32 and 62 Vpp, the transmittedlight was focused and the focal lengths of the cen-ter lens were approximately 164 and 76 mm fromthe lens surface, respectively. A larger input voltageproduced a shorter focal length since it gave a largerdisplacement amplitude of the gel. The focal lengthcould be controlled by varying the input voltage.

Curriculum Vitae: Daisuke Koyama was born in Kyoto, Japan, in September 1977. He received aDr.Eng. degree from Doshisha University, Kyoto, Japan. He joined the Precision and IntelligenceLaboratory, Tokyo Institute of Technology, as an assistant professor in 2005 and was promotedto associate professor in 2011.He is currently an associate professor in the Faculty of Scienceand Engineering, Doshisha University. He received an award for the encouragement of youngscientists at the Symposium for Ultrasonic Electronics and Engineering in 2003 and the AwayaKiyoshi Award for encouragement of research from the Acoustical Society of Japan in 2008. Hismain fields of research are in ultrasonic electronics, especially high-power ultrasonic devicesand applications of nonlinear microbubble vibration and destruction in medical ultrasonics. Dr.Koyama is a member of the IEEE, the Acoustical Society of Japan, and the Institute of ElectricalEngineers of Japan.

20


W. Littmann: A New Direction for Ultrasonic Cutting

Author: Walter Littmann, Thomas MullerATHENA Technologie Beratung GmbH (Germany)E-Mail: [email protected]: Ultrasonic cutting

Ultrasonic cutting is a well-established applica-tion for power ultrasonics, especially in industrialproduction processes, medical applications, or foodindustry. The sonotrodes used for excitation of com-mercial tools make use of longitudinal oscillationsexcited by piezoelectric converters. It is well knownthat side-edged cutting leads to best performance(so-called ”scalpel” technology), but this concept islimited to short blades. In long-blade applicationsslitted ”guillotine”-sonotrodes are state of the art(e.g. cutting of bakery products), but they do notallow for side-edged cutting. Thus ultrasound hereonly helps to reduce friction, but does not supportthe cutting mechanism itself. In this contribution aninnovative long-blade sonotrode allowing for side-edged cutting will be presented. It has constantamplitude along the whole long blade, oscillating inthe direction parallel to the cutting-edge.

The innovative system called ”ATHENA sonotro-

de” makes use of a special bending/shearing modeof a plate, a waveform which never has been inves-tigated in context with power ultrasonics until now.The new sonotrode concept will be explained in de-tail by Finite Element Calculations and by 3D lasermeasurements performed on a prototype system.Cutting experiments have been performed using astand-alone prototype system with a blade of length100 mm.

Even if the 100 mm blade is much longer than aquarter-wavelength of the longitudinal oscillation, nooscillation-nodes (”dead zones”) appear along thecutting-edge. The amplitude of about 25 µm (direc-ted in parallel to the cutting-edge) is constant alongthe whole blade. The new hand-held ultrasonic toolallows for cutting telephone-books or bakery pro-ducts by a simple, straight procedure at very lowpower consumption.

Curriculum Vitae: - 1997 diploma thesis ”Development of a Sonotrode for Ultrasonic Bondingat 120 kHz“- 2003 Dissertation at Mechatronics and Dynamics Group, Heinz Nixdorf Insitute,University of Paderborn: ”Piezoelectric Resonant-Driven Ultrasonic Transducers with NonlinearMechanical Boundary Conditions“- since 2004 Research and Development at ATHENA Techno-logy Consulting, Paderborn. - Main Topics: Development of Piezoelectric Ultrasonic Actuators,Sensors, and Transformers for Industrial Applications

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T. Maeda : Piezoelectric applications of hydrothermal (K0.48Na0.52)NbO3 ceramics

Author: Takafumi Maeda1, Peter Bornmann2, Tobias Hemsel2, Takeshi Morita1

1 University of Tokyo (Japan)2 University of Paderborn (Germany)E-Mail: [email protected], [email protected]: hydrophone, lead-free ceramics, KNN ceramics, hydrothermal method

(K,Na)NbO3 ceramics are considered as apromising candidate for the lead-free piezoelectricceramics due to their high piezoelectric constantsand high Curie temperature. However, many pro-blems exist in alkaline niobate ceramics powder fa-brication with the conventional solid-phase process.For instance, during a long time calcination pro-cess, the K+ ions evaporate, which results in alarge leakage current with the sintered ceramics.In addition, the instability of K2CO3 becomes anobstacle, especially in the weighing process. In ourstudies, the hydrothermal method could overcomethese problems because this method utilizes a so-lution reaction at high temperatures and high pres-sures, and Nb2O5 and KOH are used to synthesi-ze KNbO3 powder rather than K2CO3. The hydro-thermal method utilizes the crystallization processfrom the solution; thus, the pure crystal powdersare obtained without secondary phases. Therefo-re, the potassium to niobium ratio is automatical-ly controlled to be one (K/Nb=1). Furthermore, theoptimum chemical composition between potassiumand sodium was found to be (K0.48Na0.52)NbO3.This (K0.48Na0.52)NbO3 ceramic has difficulty inobtaining a high density by a conventional method.Hydrothermal method overcomes the problem, and

high dense (K,Na)NbO3 ceramics (98.8%) wereprepared successfully. In addition, the highly piezo-electric constant d33 was obtained; however, it didnot reach to PZT. On the other hand, the g33 con-stant of the hydrothermal KNN ceramics demons-trated high value (g33 = 28.8mV/N) similar to thatof PZT. Therefore, the hydrothermal (K,Na)NbO3

ceramics is available for sensors and energy har-vesting devices. In this research, we examinedthe possibilities of the hydrothermal (K,Na)NbO3

ceramics for the hydrophone sensor application.The hydrophone with the piezoelectric disk was co-vered with PTFE. Epoxy resin layer was used asan acoustic impedance matching layer. The hydro-phone was settled at the bottom of the water bathfor measuring the pressure level applied with a bol-ted type Langevin ultrasonic transducer. To compa-re with PZT ceramics, the hydrophones with the sa-me structure with (K,Na)NbO3 and PZT disk cera-mics were fabricated. With the (K0.48Na0.52)NbO3

ceramics hydrophone, the sound pressure spectrumwas detected. The sensitivity of (K,Na)NbO3 hy-drophone was slightly smaller than the commer-cial PZT ceramics; however, it was verified thatthe (K0.48Na0.52)NbO3 ceramics could be used forsensor applications.

Curriculum Vitae:

22


S. Mojrzisch : Vibration Frequency Adjustment of Auto-Resonant Ultrasonic Transducersby Variation of their Output Impedance in Regard to a Switching Converter

Author: Sebastian Mojrzisch, M. Weinstein, J. TwiefelLeibniz Universitat Hannover (Germany)E-Mail: [email protected]: ultrasonic transducers, tuning of frequency, auto-resonance, dynamic behavi-or,switching amplifier, harmonic balace method

In current industrial applications multiple transdu-cer systems are driven out of resonance, in orderto avoid the problems associated with individual dri-ving. Thus, the natural frequencies of multiple ul-trasonic transducers employed in welding systemshave to be matched. However,this is barely achie-ved in practice due to manufacturing tolerances andtemperature deviation during operation. Therefore,unfavorable beat frequencies can occur inevitablydue to deviations the natural frequencies among theconverters used, when each converter is driven in itsown of resonance frequency. Repealing these harm-ful effects, the exact tuning of the natural frequen-cies of the ultrasonic transducers involved in pro-cess is required. This article presents a novel me-thod to adjust the transducer’s vibration frequency

during operation. This is achieved by periodic short-circuiting of the transducer, which causes it to drivefrom resonance to anti-resonance and vice versa.Thereby the transducers have to be driven in auto-resonance to attune the oscillation frequency withthe preset resonance frequency of the system. First,the dynamic behavior of the ultrasonic transducer isdescribed analytically in regards to the short-circuitduty cycle. The resulting non-linear equation is li-nearized by the harmonic balance method. The sys-tems’ expected responses obtained by numerical si-mulations are discussed in this context. Finally theexperimental results of the implemented system arepresented and compared to the analytical and nu-merical models.

Curriculum Vitae:

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S. Mojrzisch : Piezoelectric Driven Mass Actuator for Vibration Control of Drive ChainVibrations

Author: Sebastian Mojrzisch, Jens TwiefelLeibniz Universitat Hannover (Germany)

E-Mail: [email protected]: Piezoelectric mass actuator, vibration control, motor engine, pre-stressing

In combustion engines the generated torque isoverlaid by vibrations caused by the alternating ac-tion of the motor cylinders. In order to compensatethis vibrations without loss of driving power, we pro-pose a novel mass actuator employing piezoelectricactuators. The system at hand consists of two multi-layer piezoelectric actuators which accelerate a fly-

wheel according to the parasitic disturbance. Due tothe reactive forces a reduction of vibration is achie-ved. We present the construction, which includes anovel pre-stressing technique with shape memoryalloys, and the experimental results for the vibrationreduction obtained in the test stand.

Curriculum Vitae:

24


S. Mojrzisch : Phase Controlled Frequency Response Measurement and Operation ofPiezoelectric Systems at High Vibration Amplitudes

Author: Sebastian Mojrzisch, Jens TwiefelLeibniz Universitat Hannover (Germany)

E-Mail: [email protected]: Ultrasonic, nonlinear vibration, phase control, unstable amplitude

Piezoelectric systems exhibit a nonlinear beha-vior at high vibration amplitudes. This is basicallyinduced by the material nonlinearity and results inthe generation of higher harmonic distortion. Duringoperation in resonance such systems often showthe jump phenomenon which limits the operatingpoint to the stable regime. However, the proposed

method in this paper eliminates the unstable regi-mes and ensures stable operation over the wholefrequency range. The effectiveness of the method isproven by frequency response measurements of apower ultrasonic transducer including the unstablebranches in the response. Moreover, the operationat frequencies in the unstable branch is shown.

Curriculum Vitae:

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M. Mutou : Study on Near-Field Acoustic Levitation by Multi-Mode Ultrasonic Transducer

Author: Masafumi Mutou, Takeshi MoritaUniversity of Tokyo (Japan)E-Mail: [email protected]: ultrasonic levitation, near-field acoustic levitation, non-contact transportation

Near-field acoustic levitation (NFAL) is one of thehigh-power ultrasonic applications that are based onthe nonlinear phenomena. The NFAL enables non-contact transportation by levitating kg-order objects.Until now, various NFAL and other ultrasonic resear-ches had been reported; however they used only thesimple sinusoidal vibration wave for a levitation for-ce. On the other hand, our researching group foundthat combined sine wave contributes to ultrasonicpumping power1); the ultrasonic pump is based onnonlinear fundamental. The NFAL is also a nonline-ar phenomenon, so not simple sinusoidal vibrationwave could increase its levitation force. In this study,we propose to utilize various wave forms to impro-ve NFAL performances. For this purpose, new de-signed ultrasonic transducer was fabricated, whoseresonant frequencies ratio can be controlled preci-

sely, f3/f1 = 2. Using this transducer, fundamen-tal and second vibration modes were combined andwe could control the vibration wave form by phaseshift easily. In NFAL experiment with the deformedwave, we observed the levitation distance changedby changing vibration wave form. When the vibrationwave form was convex downward trapezoid, levita-tion distance was highest; however the new pheno-menon couldn’t be explained by previous NFAL mo-del. From the experimental results, we confirmed thenonlinear bulk modulus of air contributes to NFALsignificantly and found the appropriate model usingPoisson’s law.

[1] Munesuke SUZUKI, Takuma NISHIMURA, Hiros-hi HOSAKA and Takeshi MORITA, ”‘An ultrasonic pumpwith a Langevin transducer combining high-order mode”’,IEICE Technical Report, vol.111(2011), pp37-40

Curriculum Vitae: March 2013: The University of Tokyo, B.A. in EngineeringApril 2013-present: Master course in Graduate school of frontier sciences The University of Tokyo

26


K. Nakamura : Non-Contact Mixing and Dispensing of Droplet Using Ultrasonic Levitation

Author: Kentaro Nakamura, Ryohei Nakamura, Naoki TanakaTokyo Institute of Technology (Japan)E-Mail: [email protected]: ultrasonic levitation, mixing, dispensing, droplet

It is highly demanded in pharmacy industry andnew material sciences to handle liquid without con-tact. We have been developing total non-contactsystem for this purpose being based on ultrasoniclevitation. Droplet or other kinds of small objects canbe trapped without contact at the nodal positions ofthe acoustic standing wave field excited in air. In thisstudy, we demonstrate non-contact mixing of two dif-ferent droplets suspended at adjacent nodal pointsin ultrasonic pressure field generated between a vi-brating body and a reflector. Amplitude modulationin the voltage applied to the transducer induces theoscillation of the position of the droplets along thenodal line, and results in the collision of the two dro-plets. The state of mixing is observed using a high

speed video camera. On the other hand, droplet isdispensed into a small container without contact.We employed the reflector plate with holes. Dropletfalls through the hole after turning off the ultrasonicvibration. According to our observation, the dispen-ding is carried out as free-fall due to the gravity. Theeffect of the hole diameter on the capability of levita-tion is investigated through finite element analysis ofthe ultrasonic field and experiments. Droplet of 1-4mm in diameter can be stably levitated at the no-dal point located above the hole. These techniquesof mixing and dispensing shall add new functionali-ty to the ultrasonic non-contact handling system forliquid.

Curriculum Vitae: Kentaro Nakamura was born in Tokyo, Japan, on July 3, 1963. He receivedthe B.Eng., M.Eng., and D.Eng. degrees from the Tokyo Institute of Technology, Tokyo, Japan, in1987, 1989, and 1992, respectively. He has been a professor of the Precision and IntelligenceLaboratory, Tokyo Institute of Technology, since 2010. His field of research is the application ofultrasonics and the measurement of vibration and sound using optical methods as well as fiberoptic sensors. He received the Awaya Kiyoshi Award for encouragement of research from theAcoustical Society of Japan in 1996. He awarded the best paper awards from the Institute ofElectronics, Information and Communication Engineers in 1998 and from Ultrasonic Elecronicsin 2007 and 2010, respectively. He received the JJAP editorial contribution award from the JapanSociety of Applied Physics in 2007. Dr. Nakamura is a member of the IEEE, and was the vicepresident of the Acoustical Society of Japan from 2010 to 2011. He is a TPC member of the IEEEInternational Ultrasonics Symposium.

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T. M. Pham : Ultrasonic friction reduction in sealing contacts: Characterization andreaction of system at loading positions

Author: The Minh Pham, Jens TwiefelLeibniz Universitat Hannover (Germany)E-Mail: [email protected]: ultrasonic friction reduction mechanism

Pneumatic actuators are used widely in industry.However, they have a major disadvantage, that theyare not really able to offer a soft start. One of soluti-ons of this problem is an application of friction reduc-tion in sealing contact by superposing of ultrasonicoscillations onto the surface. Up to now, the princi-ple of ultrasonic friction reduction has been resear-ched successfully in contact between metal-metal.From an experimental research, friction in sealingcontacts can be also reduced significantly when ul-trasonic oscillations are superposed onto the con-tact surface. The friction depends considerably onseal properties like stiffness or damping coefficients.In a test rid composing contact between a seal andan ultrasonic transducer, contact positions betweenthe seal and the ultrasonic superposing rod surfaceis changed, due to the macroscopic velocity of therod. It causes the changing of the ultrasonic systemload and vibration amplitudes. This contribution isdevoted to the deeper understanding of the depen-dency between sealing damping and the ultrasonic

friction reduction. Further the reaction of the trans-ducer at different contact positions between trans-ducer and the seal is investigated. An analogue mo-del is presented (using equivalent circuit transforma-tions) in order to identify the damping parameter ofthe seal. In this model the damping of the seal andthe system damping will be considered separately.The whole model is characterized in dependency onthe seal damping and also the loading contact posi-tions. The system was investigated analytically anexperimentally using a digital phase control system.A very good agreement between experimental andsimulate results is shown. Base on the achieved re-sults, the ultrasonic friction reduction mechanism isexplained clearly as a function of the sealing dam-ping. This shows a possibility to optimize the vibra-tion amplitude of ultrasonic transducer so that theeffect of sealing friction reduction could be higher.Thus provides a potential of technology for nume-rous application fields such as in a pneumatic cylin-der.

Curriculum Vitae: The Minh Pham received his bachelor from University of Transport and Com-munications Hanoi in 2000. He studied his master program in mechanical engineering from 2004to 2007 at the Technische Universitaet Darmstadt. Since 2010, he has been PhD student atthe Institute of Dynamics and Vibration Research, Leibniz Universitaet Hannover. His researchinterest is ultrasonic friction reduction in sealing contacts.

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Q. He : A Polishing Vibrator Using Bending and Longitudinal Vibration Modes and itsApplications

Author: Qing He, Li Liang, Zhang Hao, Liu ZhengInstitute of Vibration Engineering, Liaoning University of Technology, Jinzhou (China)

E-Mail: [email protected]; [email protected]: piezoelectric actuator, ultrasonic polishing, chemical-mechanical polishing, travelingwave

Aiming at the chemical-mechanical polishingtechnology of silicon wafer, a new cylindrical ultra-sonic vibrator is designed, which can generate twoorthogonal bending vibration modes and one lon-gitudinal vibration mode in the stator by means ofthree groups of piezoelectric ceramic elements. Themodes of the vibrator are the second-order bendingmode and the first-order longitudinal vibration moderespectively. And the vibrator has the bolt-tightenedsandwich structure, which can increase the vibrati-on amplitude of the working surface of the polishingpad. The bending occurs in the two orthogonal pla-

nes, which can give rise to the traveling wave mo-tion of the mass particles on the working surfaceof the pad, by applicable excitation. Whereas, whi-le vibrator working, the longitudinal vibration makesthe polishing slurry get in and out of the polishingpad easily. By means of the finite element numeri-cal analysis, the nature frequencies of the bendingmode and the longitudinal mode are optimized toapproach the same value. And by theoretical andexperimental analysis, the principle and the effectsof the polishing process are researched.

Curriculum Vitae: Main experience: 1980 - 1984 Undergraduate in Liaoning University of Engi-neering and technology, China1987 - 1990 Master postgraduate in Liaoning University of Engineering and technology, China1990 - 1994 Lecturer in Liaoning University of Technology, China1994 - 1995 Visiting scholar in RWTH Aachen, Germany1995 - 1997 Associate professor, Liaoning University of Technology, China1997 - 2000 Doctor postgraduate in Northeastern University, China2000 - 2002 Professor in Department of Mechanical and Automotive Engineering/Liaoning Uni-versity of Technology, China2002 - 2003 Visiting scholar in University Kaiserslautern, Germany2003 - Professor at Institute of Vibration Engineering\Liaoning Institute of Technology

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K.-A. Saalbach : Bond Quality investigation of Ultrasonic Assisted Composite Casting

Author: Kai-Alexander Saalbach, Patrick Freytag, Jens TwiefelLeibniz Universitat Hannover (Germany)

E-Mail: [email protected]: cavitation, ultrasonic assisted casting

Electronics components, such as microproces-sors in computers, mobile phones or tablets are be-coming increasingly powerful, thereby causing heat.Heatsinks for such electronics components requi-re high thermal conductivity. Modern heatsinks areoften assembled from different parts which consistof different materials like Copper and Aluminum. Toestablish an optimal heat transfer between the dif-ferent materials a cohesive connection is required.If such a connection is already established duringmaster forming, additional steps for joining, such assoldering, which produce a lower thermal conducti-vity between the joined workpieces than a cohesiveconnection, can be avoided. By the process of com-posite casting, different materials can be joined atthe same time creating a monolithic structure du-ring master forming. Casting experiments with Alu-

minum and Copper plates, in which a solid Copperblock was placed into a casting mold which then wasfilled with Aluminum melt, showed no satisfactoryconnection between the two metals. As a reasonfor poor connection between the Copper’s surfaceand Aluminum, impurities and oxide layers could beidentified. To remove these impurities, the generati-on of cavitation due to the application of ultrasoundwas proposed. In a previous study principle expe-riments already showed that an ultrasonic excitati-on improves the connection between Copper platesand molten Aluminum. In this study, the bond qua-lity of ultrasonic assisted composite casting is ex-amined by polished micrograph sections. Instead ofthe previously used control based on self-excitationof the ultrasonic transducer, an external excitation isused with an additional amplitude control.

Curriculum Vitae:

• Since March 2011 Research Engineer at Institute of Dynamics and Vibration Research

• 2004 to 2011 studies of Mechanical Engineering at Leibniz University Hannover

Research

• Ultrasonic levitation

• Ultrasonic assisted hybrid casting

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A. Struckas : Focusing Piezomechnical Actuators for Acoustic Levitation

Author: Arunas Struckas, Piotr VasiljevLithuanian University of Educational Sciences (Lithuania)E-Mail: [email protected]: Acoustic, levitation, piezomechanics, ultrasonic

Analysis of piezomechnical (PM) systems, forcreation of strong acoustic fields in air is done, onthe basis of analyzed data we have formulated newobjectives - research of PM systems with focusedacoustic field. Proposed a new effective PM systemwith internal excitation, comparing this system withfound analogical systems we can say that our sys-

tem is producing more lifting force and acoustic fieldis much more stable. Also we have created a newPM system with external excitation and we considerit looks promising. Modal and harmonic analysis forboth systems is done. Working prototypes are ma-de. First tests of ultrasonic levitation performed onboth systems are showing that we on the right way.

Curriculum Vitae:

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S. Li : Dynamic Reactive Power Compensation for Piezoelectric Actuator Based onTransformer

Author: Sunan Li, Huafeng Li, Benfeng ZhangState Key Laboratory of Mechanics and Control of Mechanical Structures (China)E-Mail: [email protected]: passive, controllable reactor, loss

Piezoelectric actuator has many superior charac-teristics,such as quick response, large deformation,high output force, high resolution of displacementand volumetric efficiency, etc. Therefore, it is widelyused in ultrasonic motors, ultrasonic transducer, vi-bration control and other fields. The impedance cha-racteristic of piezoelectric actuator is capacitive. Inorder to improve the efficiency of the driver of actua-tor, a parallel inductance is often used to achieve re-active power compensation. Since the capacitanceof the piezoelectric actuator varies greatly with theload, the drive’s frequency and the temperature, in-ductance with constant value can not implement dy-namic reactive power compensation for piezoelec-tric actuator. Therefore, if the value of the inductan-ce can be changed according to the change of thecapacitance, the efficiency of the driver will be in-creased. There are several controllable reactors: (1)Changing the coil turns; (2) Adjusting the air gap;(3) Thyristor controlled reactor (TCR); (4) Adjustablereactor based on magnetic-flux control. In these re-actors, changing the coil turns is easy to regulate.But the reactor can not be adjusted continuously.Adjusting the air gap is continuously adjustable andhas a simple structure. However, it responds slowlyand is noisy. The TCR changes inductance by con-

trolling trigger angle of the thyristor, which leads tothe harmonic pollution. Adjustable reactor based onmagnetic-flux control does not produce harmonic inprinciple. Yet it has some weaknesses, for instance:complex structure, low reliability, high cost, especi-ally it is not suitable for high frequency and varia-ble frequency application, such as piezoelectric ac-tuator. To achieve the purpose of dynamic reactivepower compensation for piezoelectric actuator, a no-vel scheme of passive controllable reactor based ontransformer is proposed in this paper. The transfor-mer with load can be regarded as impedance withthe parallel of an inductance and a resistance, andthe inductance can be paralleled with piezoelectricactuator to implement reactive power compensati-on. According to the equivalent impedance equa-tions of the transformer’s T-type equivalent circuit,the equivalent parallel inductance of the transformerwill be changed when the load impedance is altered,which means the reactor is passive and controllable.To decrease the loss of the proposed reactor, thevalue of parallel resistor should be increased, whichcan be realized by increasing the primary and se-condary inductance of the transformer. The validityof the scheme is proved by the theory and experi-ment results.

Curriculum Vitae: Li Huafeng did his undergraduate and graduate studies at Huazhong Univer-sity of Science and Technology, where he majored in electrical engineering and got Ph.D. Nowhe specializes in three areas: (1) Ultrasonic motor and its applications (2) Smart Materials andstructures and (3) Precise driving technology

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H. Tanaka : A Noncontact Pipette for Small Droplet Using Ultrasonic Standing Waves

Author: Hiroki Tanaka, Yuji Wada, Yosuke Mizuno, Knetaro NakamuraTokyo Institute of Technology (Japan)E-Mail: [email protected]: non-contact, levitation, dispensing, droplet, ultrasonic in air

There are potentially large needs to deliver dro-plets without contact for developing new drug andmaterials. We have been researching about ultraso-nic levitation and succeeded in non-contact trans-portation of small object over long distances and cir-cular trajectory for changing a transportation direc-tion. In this report, we investigate a method of non-contact dispensing of small droplets using ultraso-nic standing waves. A small droplet is trapped at thenodal points of ultrasonic standing wave between abending vibrating plate and a half-cylindrical reflec-tor with some holes on it. The droplet is dispensedinto a microplate through the hole on the reflector byturning off the vibration. We investigated the ultraso-nic field and the influences of the hole on the levita-tion capability. Ultrasonic standing waves were exci-ted at 27.4 kHz using a bolt-clamped Langevin-typetransducer with a stepped horn. A half-pipe-shaped

reflector was faced to the end of the horn, on whicha hole of 7 mm in diameter was drilled. The ultra-sonic field generated between the end of the hornand the reflector is simulated through the finite ele-ment method, and the results are compared with themeasured ones. The position for stable levitation ofdroplet is discussed. The maximum droplet diame-ter that can be levitated above the hole was redu-ced as the hole diameter was increased. While thehole was smaller than the half wave length of thestanding wave (6 mm), the stable levitation was pos-sible. Since the hole diameter must be larger thanthe droplet diameter for dispensing, the optimal holediameter is considered to be approximately 7 mm inthis setup. The trajectory of the droplet after turningoff the vibration was recorded using a high speedcamera, and it was proved to be free fall.

Curriculum Vitae: Mar 2012: graduated Bachelor of Engineering, Tokyo Institute of TechnologyApl 2012: matriculated Department of Information Processing, Interdisciplinary Graduate Schoolof Sience and Engineering, Tokyo Institute of TechnologyMay 2012: 9th IWPMA 2012, Hiroki Tanaka and Minoru Kurosawa, ”Design of A Plunger TypeSurface Acoustic Wave Motor”, paper 1pPA15, Hirosaki, Japan.

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P. Vasiljev : Excitation of Elliptical Trajectories in a Langevin Bending Type Transducer

Author: Piotr Vasiljev1, Dalius Mazeika2, Sergejus Borodinas1, Ying Yang3, Yin Wang3, JunZhang3

1 Lithuanian University of Educational Sciences (Lithuania)2 Vilnius Gediminas Technical University (Lithuania)3 Nanjing University of Aeronautics and Astronautics (China)E-Mail: [email protected]: Langevin bending type transducer

Langevin type piezoelectric transducers are wide-ly used for different applications such as precisionpositioning devices, micromanipulation systems, ro-botic systems and etc. Langevin transducers haveseveral attractive features: high mechanical quali-ty factor, low impedance, good clamping conditions.Typical Langevin transducer operates in longitudinalvibration mode while we suggest to excite bendingtype oscillations and to employ them for elliptical tra-jectories formation of the driving tip. Design of a halfwavelength Langevin transducer was modified forthis purpose. Special intermediate aluminium pla-te with a driving tip was added in the middle of thetransducer. Piezoceramic rings with two directionalpolarization are used for excitation the bending typeoscillations. Input voltage with shifted phase by π/2on different electrodes is applied. Direct and reverseelliptical motion of the contact tip movement is con-

trolled by changing phases of electric signal on dif-ferent electrodes. Numerical investigation of the pie-zoelectric actuator using finite elements method wasdone to analyse natural frequencies, modal shapesand actuator response to the different harmonic ex-citation sets. Optimization of the intermediate alumi-nium plate design was carried out with the objectiveto maximize parameters of the contact point ellip-tical motion by matching resonance frequencies ofthe first bending modes of the Langevin transducerand aliuminium plate. Experimental prototype of thepiezoelectric actuator was fabricated and the mea-surements of driven tip movements and mechanicaloutput were performed. The results of numerical andexperimental analysis are in good agreement. Thisnew Langevin bending type transducer can be suc-cessfully used for the linear ultrasonic motors.

Curriculum Vitae: Dalius Mazeika was born in 1969. He received his Ph.D. degree in mecha-nical engineering from Vilnius Gediminas Technical University (VGTU) in 2000. He is currentlya Professor in the Department of Information Systems at VGTU. His research interests includepiezoelectric actuators, ultrasonic motors and other smart structures.

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P. Vasiljev : Investigation of Heating Problem in a Langevin Piezoelectric Actuator

Author: Piotr Vasiljev1, Dalius Mazeika2, Sergejus Borodinas1, Ying Yang3, Xiaolong Lu3,Hanmin Peng3, Qi Zhang3

1 Lithuanian University of Educational Sciences (Lithuania)2 Vilnius Gediminas Technical University (Lithuania)3 Nanjing University of Aeronautics and Astronautics (China)E-Mail: [email protected]: Langevin piezoelectric actuators

High power Langevin piezoelectric actuators havelarge dielectric and mechanical losses. Most of the-se losses are converted into accumulating internalheat that increases the temperature of the transdu-cer. High temperature could lead to a degradationof piezoelectric material properties and indicates alow efficiency and short working life of the device.Therefore, it is important to reduce the temperatureof the actuator and to make operation of the systemefficient and reliable. Heating problem of the Lange-vin piezoelectric actuator is analyzed in the paper.Investigated actuator consists of a half wavelengthLangevin piezoelectric transducer and a half wave-length oscillation concentrator. Piezostack of the ac-tuator generates heating because of the dielectricand mechanical losses while the oscillation concen-trator has big mechanical losses in the region where

cross-section area is changing. Numerical modelingof Langevin piezoelectric actuator was carried outto find the dependence of the actuator’s temperaturefrom piezoceramic properties, excitation voltage andratio between cross-section area of the transducerand concentrator while vibration amplitudes of thecontact point remain the same. Locations of the lar-gest heat generation were defined and heat fluxes inthese regions were compared. Recommendationsfor suppressing heat generation were provided. Anexperimental prototype of the Langevin piezoelectricactuator was made. Distribution of the temperaturealong the actuator was measured when the differentcross-section area of the oscillation concentratorsare used. Results of the numerical and experimen-tal studies are compared and analyzed.

Curriculum Vitae: Dalius Mazeika was born in 1969. He received his Ph.D. degree in mecha-nical engineering from Vilnius Gediminas Technical University (VGTU) in 2000. He is currentlya Professor in the Department of Information Systems at VGTU. His research interests includepiezoelectric actuators, ultrasonic motors and other smart structures.

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M. Sborikas : Piezoelectric Cellular Polymers as Sensors or Air-Borne UltrasonicTransducer: Property Adjustment by Foam-Structure and Geometry Variations

Author: Martynas Sborikas1, Michael Wegener1,21 Fraunhofer Institute for Applied Polymer Research (Germany)2 University of Potsdam (Germany)E-Mail: [email protected]: piezoelectric, piezoelectric sensor, piezoelectric actuator, ultrasonic transducer

Piezoelectric polymer materials are of broad in-terest for sensor and actuator applications as wellas for research of dipolar orientation processes,space-charge trapping mechanism and electrical-mechanical interactions. Ferroelectrets are presen-ting one of the recent developments in the field ofpiezoelectric transducer materials [1, 2]. In between,their processing and working mechanism are well in-vestigated. In summary, the concept is like this: hu-ge electrical dipoles based on trapped charges areembedded in a soft cellular polymer matrix. Thus allrequirements for piezoelectricity, a symmetry brea-king of the polarization and a deformable matrixwhich allows dipole size changes are given in tho-se ferroelectrets.Within the last years, ferroelectrets with a cellular-foam structure were developed from different kindsof polymers such as polypropylene (PP), polyethy-lene terephthalate (PET), polyethylene naphthalate(PEN) as well as cyclo-olefine polymers. In recentpublications, new development and processing pos-sibilities of cellular electret systems are evaluated.Usually, single homogeneous and meshed electretlayers are combined to thin sheets [3]. For thesesystems, the electret material, the cellular structure,the charging and thus the electro-active properties

can be very well controlled and adapted by the opti-mal processing of the separate sheets. However, interms of applications, classical PP ferroelectrets stillplay the major role.This classical ferroelectret concept will also be thebasis of our material development presented here.We evaluate optimisation attempts such as coatinglayers and geometrical variations in order to provi-de transducer materials with high operating voltagesand low resonance frequencies. In the presentation,the processing of such systems, their electrical char-ging and the resulting mechanical and piezoelectricproperties are discussed. The suitability of the de-veloped materials for air-borne ultrasonic purposesis proved with demonstrated high piezoelectric ac-tivities and low resonance frequencies of down toabout 120 kHz determined on freely vibrating samp-les.

[1] M. Wegener and S. Bauer, ChemPhysChem 6,1014-1025 (2005).[2] M. Wegener, in: New Materials for Micro-scale Sen-sors and Actuators - An Engineering Review, ed. S. Wil-son and C. Bowen, Mat. Sci. Eng.: R: Rep. 56, 78-83(2007).[3] R.A.P. Altafim, X. Qiu, W. Wirges, R. Gerhard, R.A.C.Altafim, H.C. Basso, W. Jenninger, and J. Wagner, J. Ap-pl. Phys. 106, 014106 (2009).

Curriculum Vitae: Michael Wegener was born on September, 24, 1968 in Neuruppin, Germany. He studied physics and mathematics in

a teachers program at the University of Potsdam from 1990 to 1995. In February 2000, he received the Ph.D. degree in physics. Topics of his PhD

work were the electrical properties of polymers (e.g., pyro-, piezo-and ferroelectricity), and the change of these electrical properties during and

after electrical, thermal and chemical variations of the polymers. From 1997 until 2000, as Ph.D. student, he was admitted to the DFG-sponsored

joint Research Training Group on ”Polymer Materials” of the Berlin and Potsdam universities and received a merit-based scholarship. He also

completed an industry internship at Huber & Suhner AG in Herisau, Switzerland during July and August 1998. His task was the construction

of a pilot plant for the production and electrical poling of piezoelectric polymer cables. From March 2000 until December 2006 he worked as a

senior member of scientific staff and a project manager in the Applied Condensed-Matter Physics group at the University of Potsdam. He was

responsible for several large national as well as European network projects. Main topics of his research were the investigation of novel voided

space-charge electrets (ferroelectrets) as well as of ferroelectric polymers, their electrical and electromechanical properties as well as their

applications in piezoelectric sensors and actuators. Since January 2007 he is working at the Fraunhofer Institute for Applied Polymer Research

(IAP) in Potsdam-Golm. In 2007 he finished the Habilitation (highest German University degree). Here, the underlying research work was the

development of a new class of piezoelectric material, especially of very soft piezoelectric polymer foams, so-called ferroelectrets. His current

research fields are electro-active materials, such as polar polymers, polymer-ceramic composites, voided space-charge electrets as well as

elastomers.

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W. Wurpts : Some Aspects on the Dynamics of Ultrasonic Actuators with Impacts

Author: Wiebold Wurpts, Jens TwiefelLeibniz Universitat Hannover (Germany)

E-Mail: [email protected]: ultrasonic, impact, contact, harmonic balance

In many ultrasonic applications like motors, wel-ding or ultrasonic assisted machining, the energyis brought into the process with impacts. But theintermittent contact also introduces a strong nonli-nearity into the system and therefore needs specialconsiderations. In this contribution different nonline-ar phenomena of an ultrasonic tool with one impactpoint are discussed by means of simulation and ex-periment. First the influence of different mountingsof the tool on its frequency response is analyzedutilizing an equivalent circuit model that has beenextended by a static degree of freedom. The mo-del is solved analytically for different mountings, em-ploying the harmonic balance method and the solu-tion is compared with experimental data. Dependingon the mounting of the tool and the stiffness of theprocessed material the mechanical displacements

may harmonically distort. In order to consider the-se distortions higher-order harmonic amplitudes areincluded into the simulations. The used technique isthe so called multi harmonic balance method. Thisis solved numerically and its results are comparedwith the measurements. Non-sinusoidal excitationsare also discussed within the multi harmonic balan-ce approach. When ultrasonic systems with impactsare driven, low frequency displacements are some-times excited as well. The excitation mechanism ofthe low frequency vibrations is explained and thesequasi periodic movements are shown to be a soluti-on of an extended equivalent circuit model. The lowfrequency vibration is associated with a parameterchange that leads to an amplitude modulation of thevelocity and the current. These effects are illustratedwith measurements and explained by simulations.

Curriculum Vitae: Wiebold Wurpts received his diploma degree in mechanical engineering in2008 at the Leibniz Universitat Hannover and now works as research assistant on ultrasonicsystems especially with nonlinear contact.

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W. Wurpts : Piezoelectric Equivalent Circuits and Finite Element Model Order Reduction

Author: Wiebold Wurpts, Jens TwiefelLeibniz Universitat Hannover (Germany)E-Mail: [email protected]: Equivalent Circuit, Model Order Reduction

Equivalent circuits are usually the first choi-ce to describe dynamic piezoelectric systems, asthey allow the description of a complete electro-mechanical system with one or more modes. Theparameters of the equivalent circuit model areusually identified by an experimental or simulatedfrequency response. Therefore equivalent circuitsrepresent the electrical input behavior very well,but in general do not supply a clear description ofthe complete structural dynamic. In this contributionequivalent circuits are presented as the result of amodal order reduction. This approach provides a de-eper understanding of the equivalent circuit and theconcise consideration of arbitrary loadings, which isdifficult so far. The reduction technique is exempli-fied by a one-dimensional piezoelectric rod, whe-re it exactly agrees with the classical results. It is

shown that the circuit representation depends on,whether the short- or the open- circuited modes areused within the reduction. Furthermore the resultingcapacity of the equivalent circuit depends on howmany modes are considered, or generally speakingon residual terms. Beside the theoretical considera-tions for the piezoelectric rod, the method gains itspractical value when applied for complete technicalsystems. Therefore the reduction and the necessa-ry matrix algebra are also shown for discretized fi-nite element models. The method is demonstratedfor a base-excited piezo beam with a harvesting cir-cuit and an ultrasonic transducer with different pos-sible contact positions. With the proposed methodan exact description of the load is achieved for bothsystems.


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W. Wurpts : A transfer matrix method for the design of resonant piezoelectric devices

Author: Wiebold Wurpts, Peter Bruns, Jens TwiefelLeibniz Universitat Hannover (Germany)

E-Mail: [email protected]: Transfer matrix, piezoelectric design study

The working principle of many resonant piezo-electric devices is described by only one direction ofvibration. Ultrasonic knifes vibrating mainly in longi-tudinal direction and piezoelectric beam harvestersperforming only bending vibrations fall under this de-finition, to give but two examples. With the transfermatrix method the devices are modeled with respectto this working direction only. Thus efficient and si-gnificant design studies can be carried out. In thiscontribution we propose a new method based uponsimple matrix algebra for the assembly of differenttransfer matrixes. Even complex piezoelectric devi-ces can be analyzed with the proposed method as

long as the assumptions of a one dimensional wa-ve propagation holds. The computational implemen-tation allows the straightforward simulation and va-riation of different systems. Applying the method athand to ultrasonic assisted machining of stone con-cludes the paper. The reliability of this method is de-monstrated by comparison with finite element solu-tions as well as measurements. It will be shown thatimplementation of the new method leads to an ea-sy calculation of loading influences on the vibrationshape, in contrast to the finite element solution. Fur-thermore, calculated and measured vibration cha-racteristics are in perfect agreement.


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C.-C. Yin : Piezoelectric Fiber Composite Acoustic Wave Sensors

Author: Ching-Chung Yin, Yu-Chien Wu, Shih-Ming HsuNational Chiao Tung University (Taiwan)E-Mail: [email protected]: Acoustic wave sensors, interdigitated electrodes, piezoelectric fiber composite

An acoustic wave sensor made from piezoelectricfiber composites (PFC) with new electrode arrange-ment for structural health monitoring (SHM) appli-cation is developed. The present device is symme-trically polarized with respect to its mid-plane andactuated or sensed by anti-symmetrically alignedelectrodes. Two types of PFCs, which are activefiber composites (AFC) and macro-fiber composi-tes (MFC) with different cross sections, have beenutilized as smart materials and structures becauseof excellent abilities of actuation and conformabili-ty. The PFC transducer polarized and actuated bysymmetric interdigitated electrodes extends or con-tracts simultaneously when a voltage is applied onthe electrodes. However, symmetric configuration li-mits PFC being a short-wavelength acoustic wa-ve sensor. Instead, fixed-wavelength acoustic wa-ves can be launched and sensed by the novel de-vice. A parametric study is conducted to understandthe optimal design of electrodes, including width of

the electrode, the gap between adjacent electrodes,and so on. The operating frequency is relevant tothe electrode pitch and dispersive characteristics ofthe host structures. Symmetric electrode layout isadopted during poling process since the poling in-tensity can be almost twice of that yielded by anti-symmetric arrangement. The interdigitated electro-des are divided into two sets with a space intervalof one and a quarter wavelength. A forward trave-ling wave can be formed by constructive interferenceof two equal-intensity waves actuated by orthogonalsinusoidal low-voltage signals exerting on the elec-trodes. The lab-made 1 MHz acoustic wave sensorsachieve high directivity and very good consistencyin both measured and predicted dynamic characte-ristics. The present acoustic wave sensor featureslightweight and conformable, and can form an arrayfor damage detection in the host structures withoutadded mass or stiffness influences.

Curriculum Vitae: Ching-Chung Yin is an Associate Professor in the Department of MechanicalEngineering at National Chiao Tung University, Hsinchu, Taiwan. He received his B.Sc. and M. Sc.degrees from National Taiwan University in 1981 and 1983, respectively. In 1990, he received thePh.D. degree in Aerospace Engineering from University of California, Los Angeles (UCLA). Hehas research experience in ultrasonic nondestructive evaluation for more than 20 years. He hasserved as an executive board member of the Society for Nondestructive Testing and Certificationof Taiwan since 2010. His research interests include structural health monitoring, acoustic wavesensors, ultrasonic motors, acoustic manipulation, and photomechanics.

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Materials

Materials

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R. Bansevicius : Piezoelectric Active Bearings and Supports: Structures, Characteristics,Applications

Author: Ramutis Bansevicius1, Genadijus Kulvietis21 Kaunas University of Technology (Lithuania), 2 Vilnius Gediminas Technical University (Lithua-nia)E-Mail: [email protected], [email protected]: Active kinematic pairs, Piezoelectric motors, Active bearings, Piezoelectric supports

Active bearings and supports are based on theconcept of Active kinematic pairs, which coverswhole range of multi-degree-of-freedom kinematicpairs and enable:

• Control of the number of degrees-of-freedomby means of friction control in the contact zoneor generation of static or quasi-static deforma-tions of the element of the pair;

• Generation of forces and moments in the con-tact zones;

• Effecting additional functions - self-diagnostics, multi-functionality, adaptivity andself-assembly;

• Implementing two levels of degrees-of-freedom. The first level comprises displace-ments, produced by transformation of oscil-lations into continuous motion; the second -deals with small displacements, implementedby means of inverse piezoelectric effect andsectioning of electrodes.

Important feature of Active support is that it has zeroprocessing datum surface errors, and can be widelyused in precise measuring and manufacturing sys-tems.Several modifications of Active bearings are presen-ted. In one of them piezoelectric block, having a pre-cise V -shaped groove for checking the roundness

or concentricity of precise shafts, is presented. Pie-zoelectric V-block realizes the rotation and transla-tional motion of the precise shaft; another modifica-tion deals with rotation of shafts, mounted in oscilla-ting centers. The absence of rotating centers com-pletely exclude the processing datum surface errorsand ensures high resolution of angular position ofshafts. The examples of active centers are given,including cases with traveling waves and superposi-tion of resonant longitudinal - torsional oscillations.Very effective applications include laser scanningsystems, containing mirrors, actuated by piezoelec-tric transducers, attached directly to mirror. It isshown that it is feasible to effect 2D scanning of la-ser beam with high resolution and small responsetime using bimorph type piezoelectric transducerswith controlled direction of oscillations. Some expe-rimental results are given; they include transient mo-de of operation in scanning and direct displacementmodes.Several modifications of Active bearings with sever-al degrees of freedom are presented. They includepositioning on the plane systems and rotation of thesphere. One application deals with attitude control ofnanosatellites, realizing miniature piezoelectric sys-tems, effecting 3D control of satellites angular posi-tion in the space.The presentation is illustrated by a number of vi-deos, showing the functional abilities and specificsof developed devices.

Curriculum Vitae: Ramutis BANSEVICIUS, Professor of Mechatronics Center for Research, Studies and Information (Kaunas University

of Technology, Lithuania), is carrying on R&D activity in the area of development and application of smart materials. He is the co-author of the first

monograph on Piezoelectric motors, published in Vilnius in 1981 and later issued in USA in 1988. Member of Lithuanian Academy of Sciences; in

2000 - 2007 was Rector of Kaunas University of Technology. He introduced the concept of Piezomechanics as a sub-system of Mechatronics and

developed wide range of adaptive multi-degree-of-freedom high resolution devices, based on transforming ultrasonic oscillations into continuous

or step motion (Positioning systems on the plane, Laser scanning/deflecting systems, Piezoelectric robots, etc.).

42

Materials

T. Q. Bui : Extended Finite Element Simulation of Stationary Dynamic Cracks inFunctionally Graded Piezoelectric Solids

Author: Tinh Q. Bui, Chuanzeng ZhangUniversity of Siegen (Germany)E-Mail: [email protected]@uni-siegen.deKeywords: nonhomogeneous FGPM

Due to the inherent characteristics of the electro-mechanical coupling, multiphase piezoelectric ma-terials have been increasingly used in a wide rangeof smart devices and structures as sensors, actua-tors, transducers, etc. However, smart piezoelectricmaterials tend to fracture during manufacturing andunder in-service loading conditions because of theirbrittleness in nature. To improve the reliability andstrength of such piezoelectric materials, functional-ly graded piezoelectric material (FGPMs) have be-en emerged by introducing the concept of gradientdistribution to piezoelectric materials. Many piezo-electric devices and structures are often exposed todynamic electrical and/or mechanical loading in en-gineering applications, thus it is of great importanceto better understand the dynamic fracture behaviorsof cracked piezoelectric materials. In this contributi-on, transient dynamic fracture behaviors of crackedFGPMs under impact loading by using the extendedfinite element method (XFEM) are studied. The ma-

terial properties are assumed to have an exponen-tial variation along one direction. A dynamic XFEMmodel associated with the stable implicit time inte-gration technique is developed to serve that pur-pose, while the contour interaction integral techni-que is employed to accurately evaluate the relevantdynamic fracture parameters of FGPMs. Extensivenumerical examples with the electrically impermea-ble crack-face boundary condition are considered,and the dynamic intensity factors (DIFs) obtainedby the X-FEM are presented. The effects of the im-pact loads, poling direction, material gradation, elec-tric displacement loading, material gradient coeffi-cient, etc. on the DIFs are analyzed. We have foundthat the dynamic crack behaviors in the nonhomo-geneous FGPMs are much more complicated thanthose of the homogeneous materials. This work ishelpful in the design of smart functional piezoelec-tric materials in engineering applications.

Curriculum Vitae: Tinh Q. BUI was born in Quangnam, Vietnam, in 1979. He received the BScdegree in Mathematics and Computer Sciences from the National University of Ho Chi Minh City,Vietnam, in 2002. He then earned a European MSc degree in Mechanics of Constructions fromthe University of Liege, Belgium in 2005. In 2009, he graduated in Mechanical Engineering with a”Dr. techn” degree from the Institute of Lightweight Design and Structural Biomechanics, ViennaUniversity of Technology, Austria. He was a postdoctoral fellowship at the SMS center, Depart-ment of Mechanics and Materials Processing, Ecole des Mines de Saint-Etienne, France. Since2010, he works as a researcher at the Department of Civil Engineering, University of Siegen,Germany. His research interests are in the areas of computational mechanics, soft-computingmethods, material modeling, wave propagation, and numerical methods developments. His cur-rent interest concentrates on fracture and failure mechanics in multifield composite materials.

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X. Guo : Preparation and Properties of 2-2 Piezoelectric-Damping Composites

Author: Xiaojing Guo, Dongyu Xu, Xinchun Xie, Shifeng HuangUniversity of Jinan (China)E-Mail: mse [email protected]: 2-2 piezoelectric-damping composites, damping properties, dielectric properties, thepiezoelectric strain factor d33

Piezoelectric damping material has become anew research hotpot in the field of vibration and noi-se reduction because of the unique mechanism ofenergy loss. In this paper, 2-2 type piezoelectric-damping composites were fabricated using epoxyresin as the matrix and piezoelectric ceramic asfunctional phase by cut-filling method. The effects

of ceramic volume fraction and shape parameterson the damping properties, dielectric properties andthe piezoelectric strain factor d33 were studied andthe damping mechanism was analyzed. The resultsindicate that compared to the pure epoxy resin, thedamping properties of 2-2 type piezoelectric dam-ping composites is improved.

Curriculum Vitae:

44

Materials

M. Gurbuz : Effect of the Excess PbO on Densification of Electrospray DepositedPb(Zr0.52Ti0.48)O3 Thick Films

Author: Mevlut Gurbuz1,2, Hideaki Sakurai3, Yoshirou Kuromitsu3, Aydin Dogan1

1 Anadolu University (Turkey)2 Ondokuz Mayis University University (Turkey)3 Mitsubishi Materials Corporation (Japan)E-Mail: [email protected], [email protected], [email protected], [email protected]: Lead zirconate titanate (PZT) films

Lead zirconate titanate (PZT) films are fabrica-ted by CVD, PVD, spin coating and screen printingfor various piezoelectric film applications. In recentyears, electrospray deposition (ESD) technique isalternative method to fabricate PZT thick films dueto its high material efficiency, simplicity of experi-mental set up, wide choice of precursor and lowcost. Therefore, the aim of this study is to fabricatehigh density PZT films using ESD technique. In thisstudy, solid state synthesized Pb(Zr0.52Ti0.48)O3

nano powders (nearly 80nm) (Nanotech Corp.) andMMC PZT sol (Mitsubishi Corp.) were used to pre-pare PZT composite slurry. PZT nano powder andPZT sol ratio were varied between 0.015 to 0.8

gr/ml. Homogeneously prepared PZT compositeswere deposited on silicon wafer with ESD. The ESDcoated samples were heat treated at 830C in 3husing certain amount of excess PbO. Surface andcross section of the fabricated film morphologieswere characterized with scanning electron micros-copy (SEM) after thermal processing. The resultsshowed that, more homogeneous film thicknesseswere observed when MMC PZT sol was mixed withPZT nanoparticles. After heat treatment coated sur-faces had porous and cracked morphology withoutexcess PbO. On the other hand, strongly dense filmstructure and thickness were observed using excessPbO during heat treatment.

Curriculum Vitae:

45

Table of Contents

M. Gurbuz : Dielectric and Leakage Current Analysis of Li doped NBT-BT Single Crystals

Author: Mevlut Gurbuz1,2, Aydin Dogan1

1 Anadolu University (Turkey)2 Ondokuz Mayis University (Turkey)E-Mail: [email protected], [email protected]: lead-based piezoelectric materials

The use of lead-based piezoelectric materials(PZT, PMN) in the near future will be prohibi-ted by environmental regulations due to their highlead content and toxic nature. Nowadays lead free94Na0.5Bi0.5TiO3−6BaTiO3 (NBT-BT) based ma-terials are receiving considerable attention by re-searchers. On the other hand, polarization of theNBT-BT materials is main problem due to their highconductivity. Therefore, the purpose of this study isto fabricate and characterize Li doped NBT-BT sin-gle crystal using flux growth technique. In this stu-dy, Li doped NBT-BT single crystals were success-

fully grown by flux growth technique using NBT-BTsynthesized powder. Temperature and frequency-dependent dielectric and leakage current proper-ties of the Li doped NBT-BT single crystals wereanalyzed by HP4194A impedance/gain phase ana-lyzer, GW-INSTEK LCR-8101 meter and AIXACT(aixPES/CMA), respectively. From the results, diel-ectric values of the unpoled samples between 1 kHzto 100 kHz at 450C were measured as 22630, 9020and 2915, respectively. Also, leakage current densi-ty of Li doped NBT-BT crystals were nearly 2,5 timesgreater at 120C when compared with 90C.

Curriculum Vitae:

46

Materials

N. Jackson : Flexible Aluminium Nitride/Polyimide Piezoelectric material for MEMSapplications

Author: Nathan Jackson, Lynette Keeney, Alan MathewsonTyndall National Institute (Ireland)E-Mail: [email protected]: Aluminium Nitride, polyimide, piezoelectric, flexible, MEMS

Piezoelectric materials are widely used in nume-rous applications including energy harvesting de-vices, sensors, actuators, and transducers. Mostpiezoelectric materials are stiff, which is not desira-ble in specific applications requiring flexibility suchas biomedical implants or low resonant frequencycantilevers for energy harvesting. For these applica-tions polyvinylidene difluoride (PVDF) is often used.However, PVDF has a low melting temperature andrequires poling, which makes fabrication more dif-ficult. Aluminium nitride (AlN) has been previouslydeposited onto polyimide with limited success whichhas resulted in low piezoelectric properties. This pa-per aims at developing a flexible piezoelectric AlNfilm with improved piezoelectric properties.

AlN was successfully deposited onto polyimide(HD 2611) material using DC sputtering techniques.The polyimide used in this application has uniqueproperties which improve the quality of the depo-

sited AlN. The polyimide used is a semi-crystallinematerial with a low CTE, low internal stress, andlow surface roughness due to spin coating. The filmresulted in a flexible piezoelectric film that is easyto integrate into a traditional fabrication process andcan be developed into a MEMS structure that doesnot require poling. Both the polyimide and AlN havehigh melting temperatures which makes fabricationeasier, and the new flexible material could be usedin high temperature (¿300C) applications.

This paper highlights the characterisation of theflexible AlN film. Previous reports of AlN on polyimi-de showed d33 values of 0.56 pC/N and a FWHMof 8.3. The flexible AlN material generated in thispaper has a (002) AlN FWHM of 5.16 and a d33 va-lue of 1.12 pC/N. These values are still lower thanreported values of AlN on Si. However, optimisationof the deposition process will significantly increasethese values in future studies.

Curriculum Vitae: Dr. Nathan Jackson received his Ph.D in Biomedical Engineering from ArizonaState University in 2009. His Ph.D was focused on developing novel Bio-MEMS devices. Nathanjoined Tyndall National Institute in Cork, Ireland as a Researcher in 2009, where he has beenthe technical lead investigator looking at piezoelectrics in MEMS energy harvesting applications.He has been involved with optimising the deposition of Aluminium Nitride for various applicationsincluding depositing it onto a flexible material for biomedical applications. He was the chair for theBioInstrumentation and Device session for the BioMed 2012 conference, and he was the GuestEditor of Micro and Nanosystems Journal on Piezoelectrics. His research interests are in the areaof Bio-MEMS sensors and transducers, and neural interface devices. He is a member of IEEE,EMBS, and IMAPS.

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Table of Contents

V. Kalem : Effect of PMnN Content on the Electrical Properties and Phase TransitionBehaviors of [PSLZT]-[PMnN] Ceramics

Author: Volkan Kalem1, Muharrem Timucin1

1 Selcuk University (Turkey)2 Middle East Technical University (Turkey)E-Mail: [email protected]: Dielectric, Piezoelectric, PZT, PSLZT, PMnN

(1−x)[Pb0.94Sr0.05La0.01(Zr0.54Ti0.46)0.9975O3]−x[Pb(Mn1/3Nb2/3)O3] (abbreviated as PSLZT-PMnN) piezoelectric ceramics were prepared bythe conventional sintering method. The effect ofthe amount of PMnN on phase structure, mi-crostructure, dielectric and piezoelectric propertiesof PSLZT-PMnN was investigated in detail. X-raydiffraction investigation indicated that all samplesexhibited a single phase perovskite structure. Thephase structure changed from tetragonal to singlerhombohedral symmetry and the Curie temperature

decreased gradually as the amount of PMnN incre-ased. The dielectric constant, piezoelectric constantand coupling factor obtained their maximum valuesat x = 0.02± 0.01, while the transition temperaturedecreased with increasing PMnN content in the sys-tem. The composition of x=0.03 exhibited favorabledielectric and piezoelectric properties (Qm = 400,d33 = 660pC/N , kp = 0.60, KT = 1940, tanδ = 0.90% and TC = 247C) which makes thissystem a potential candidate for piezoelectric ac-tuator and sensor applications.

Curriculum Vitae:

48

Materials

Y.-S. Lee : Effects of Annealing Temperature and Oxygen Pressure on ElectricalProperties of (Na0.5K0.5)NbO3 − CaTiO3 Films Grown on Pt/T i/SiO2/Si Substrates

Author: Youn-Seon Lee, Tae Seo, Bo-Yun Kim, Sahn NahmKorea University (South Korea)E-Mail: [email protected]: NKN-CT thin film, oxygen partial pressure, Electrical Property, oxygen vacancy, leakage current

Amorphous (Na0.5K0.5)NbO3−CaTiO3(NKN−CT ) thin films were grown on the Pt/T i/SiO2/Sisubstrates at 300 C and subsequently annea-led at various temperature under the NKN atmo-spheres. Moreover, the structural and the electri-cal properties of the NKN-CT thin films annealedat various temperatures were investigated. Whenthe annealing temperature was lower than 830 C,theK4Ca2Nb10.2O30(KCN) secondary phase wasformed. However, when the NKN-CT thin films an-nealed above 830 C, the homogeneous NKN-CTphase was formed without the secondary phase.The KCN phase was considered as a transient pha-se, which was developed due to the insufficient an-

nealing temperature. When the NKN-CT thin filmwas annealed at 830 C under NKN atmosphere,it showed the high dielectric and piezoelectric con-stants: εr = 800 and d33 = 120. Moreover, theNKN-CT thin films were post-annealed after thedeposition of Pt top electrode under various oxy-gen partial pressures (OPPs) and the effect of theOPP on the electrical properties of the NKN-CT thinfilms was also investigated. The leakage current ofthe films were considerably influenced by the OPP.Finally, using this NKN-CT thin film, the flexible pie-zoelectric nano-generator was fabricated and theirenergy harvesting characteristic was also investiga-ted.

Curriculum Vitae: Yang Bai received the BEng degree of Materials Science and Engineeringfrom Tianjin University, China, in 2011. He is now a 2nd year Ph.D. student of the FunctionalMaterials Group, School of Metallurgy and Materials, University of Birmingham, UK. His researchproject focuses on optimisation of piezoelectric composition (lead-based, lead-free) and fabrica-tion/application of free-standing piezoelectric thick-film configuration for energy harvesting.

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Table of Contents

J. Lee : Stress Modulation of Aerosol Deposited PbTiO3 Film for High TemperatureApplications

Author: Jungkeun Lee1, Soohwan Lee1, Jong-Pil Lee2, Yun-Soo Lim2, Dong-Soo Park3, JunghoRyu3, Dae-Yong Jeong1

1 Inha University (South Korea)2 Myongji University (South Korea)3 Korea Institute of Materials Science (South Korea)E-Mail: [email protected]: Aerosol deposition, PbTiO3 film, high temperature Tc, stress

Piezoelectric materials with Tc over 500 C aredemanded for the high temperature sensor and ac-tuators, for example, for automobile and aerospaceapplications. Tc can be displaced by changing eitherthe point defect chemistry or internal stress. Espe-cially, stress in the thin/thick film could be easilymodulated by adopting using the different substra-te with the various thermal expansion coefficients.During the cooling process, as the thermal expansi-on coefficients of substrate and film were different,stress could be built. PbTiO3 (PT) has a relatively

high Tc of 493 C and it is plausible to expect a Tcof over 500 C to be achievable by inducing the re-sidual stress in the PT film. However, PT has largetetragonality (large c/a ration) at the room tempe-rature and experiences the large volume expansionduring the para to ferro phase transition. Therefore,it is not easy to fabricate the sound thick film withoutbreakage. Using the aerosol deposition, we fabrica-ted the nanosize PT reducing the tetragonality. Inaddition, PT was deposited on the different substra-tes to control the magnitude of stress in film.

Curriculum Vitae:

50

Materials

S. Lee : Control of Hysteresis in Ferroelectric Materials with Grain Size

Author: Soohwan Lee1, MinGeun Choi1, Jungkeun Lee1, Dong-Soo Park1, Jungho Ryu2,Dae-Yong Jeong1

1 Inha University (South Korea)2 Korea Institute of Materials Science (South Korea)E-Mail: [email protected]: hysteresis, nano grain, high energy density

Materials with large dielectric constant and slimhysteresis have been attracted for actuator, electro-caloric, and high energy density capacitor applica-tions. In general, even though ferroelectric materi-als have large dielectric constant, large hysteresisloop hindered ferroelectric to be used for high ener-gy density capacitor applications. Large hysteresisis originated from the macrosize domain and slim

hysteresis can be realized by nanosize domain. Re-laxor ferroelectric material is the typical example forslim hysteresis. Ceramic relaxor can be obtained bychanging the chemical composition. In this experi-ment, we fabricated the ceramic dense film with na-nosize grain, which has typical ferroelectric compo-sition. The dielectric, piezoelectric, and energy sto-rage properties were characterized.

Curriculum Vitae:

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S. J. Rupitsch : Simulation Based Approach to Identify Temperature-Dependent MaterialParameters of Piezoceramics

Author: Stefan J. Rupitsch, Jurgen Ilg, Reinhard LerchFriedrich-Alexander-University Erlangen-Nuremberg (Germany)E-Mail: [email protected]: identify, parameter variations

With a view to reducing development time as wellas costs of devices incorporating piezoceramic ma-terials, finite element (FE) simulations are employedto predict their mechanical and electrical behavior.Apart from the setup of the devices, precise materialparameters of the piezoceramics are indispensableto obtain reliable simulation results. Since the deviceperformance should be guaranteed over a certaintemperature range, numerical simulations require inaddition the variation of these material parameterswith respect to the ambient temperature.

Common approaches to identify material parame-ters of piezoceramics are based on the IEEE/ANSIstandard. Thereby, the frequency resolved electricalimpedance of several samples exhibiting differentgeometries is acquired and analyzed. By meansof simple analytical relations, 10 independent ma-terial parameters can be computed which entirelycharacterize the piezoceramic material. However,the IEEE/ANSI standard presumes monomodal me-chanical vibrations of the investigated samples that

cannot be fulfilled in practice. As a result, the deter-mined material parameters do not yield reliable si-mulations for piezoceramics. On account of this fact,we developed an alternative approach for the iden-tification of accurate material parameters. The ap-proach is based on comparisons of measurementsand FE simulations. In particular, the electrical be-havior of two blockshaped piezoceramic samplesfeaturing different directions of polarization is inves-tigated. With the aid of an Inverse Scheme, the ma-terial parameters serving as input quantity of the FEsimulation are adjusted in a convenient way. Sincethis approach utilizes FE simulations, the identifica-tion procedure is not based on the assumption ofmonomodal mechanical vibrations.

In order to study the variation of material para-meters with respect to the ambient temperature, thepiezoceramic samples were investigated in a clima-tic chamber. We will present the parameter varia-tions for both, soft and hard piezoceramics in thetemperature range -35 C to 145 C.

Curriculum Vitae: Stefan J. Rupitsch was born in Kitzbuehel, Austria, in 1978. He received hisDiploma and Ph.D. degrees in Mechatronics from the Johannes Kepler University Linz, Austria,in 2004 and 2008, respectively. In 2004, Dr. Rupitsch was a Junior Researcher at the Linz Centerof Mechatronics. From 2005 to 2008, he was with the Institute of Measurement Technology atthe Johannes Kepler University Linz. Currently, he is a Postdoctoral Researcher at the Friedrich-Alexander-University Erlangen-Nuremberg (Chair of Sensor Technology), Germany. His researchinterests include electro-mechanical transducers, simulation-based material characterization aswell as noncontacting measurements.

52

Materials

J. Ryu : Giant Magnetoelectric Characteristics of Ni/PMN-PZT/Ni Laminate Compositesand Anisotropic Crystallographic Effect

Author: Jungho Ryu1, Rahul C. Kambale1, Deepak Patil2, Kee Hoon Kim2, Dae-Yong Jeong3,Dong-Soo Park1, Woon-Ha Yoon1, Jong-Jin Choi1, Jong-Woo Kim1, Cheol-Woo Ahn1, Byung-Dong Hahn1

1 Korea Institute of Materials Science (South Korea)2 Seoul National University (South Korea)3 Inha University (South Korea)E-Mail: [email protected]: piezoelectric single crystal, Magnetoelectric, anisotropy

Magnetoelectric (ME) laminate composites ofNi and <001> or <011> oriented piezoelectricPb(Mg1/3Nb2/3)O3-Pb(Zr,Ti)O3 single crystal werefabricated and studied their ME behaviors. ME coef-ficient (αME) and electromechanical resonance fre-quency were found to be strongly dependent on theorientations as well as thickness ratio. The αMEwas found to be 0.462 V/cm·Oe and 1.02 V/cm·Oe

for <001> and <011> orientations respectivelyat 194Hz, increasing to 100-150 V/cm·Oe at reso-nance frequency drive ∼ 350 kHz. Frequency de-pendent αME exhibited one and three resonancepeaks for <001> and <011> orientations respec-tively. The orientation dependent αME and anisotro-pic nature of <011> orientation will be discussed.

Curriculum Vitae:

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J. Ryu : Exceptionally Enhanced Magnetoelectric Properties of PZT Thick Film on NiSubstrate with Oxide Electrode

Author: Jungho Ryu1, Rahul C. Kambale1, Dong-Soo Park1, Woon-Ha Yoon1, Jong-Jin Choi1,Jong-Woo Kim1, Cheol-Woo Ahn1, Byung-Dong Hahn1, Dae-Yong Jeong2

1 Korea Institute of Materials Science (South Korea)2 Inha University (South Korea)

E-Mail: [email protected]: Aerosol deposition, Magnetoelectric, LaNiO3, Acoustic Impedance, Thick film

The composites can be formed by combi-ning a ferromagnetic/magnetostrictive and ferro-electric/piezoelectric phases together which provi-des a new class of functional materials, termedas magnetoelectric (ME) materials; the cross coup-ling between magnetostrictive and piezoelectric ef-fect results in a new product property called ma-gnetoelectricity. In general, strong interfacial coup-ling between the two phases is required to achievethe optimal ME output. We have characterized themagnetoelectric properties of Pb(ZrTi)O3/LaNiO3/Ni(PZT/LNO/Ni) composites, which are fabricated byusing the aerosol deposition. LNO acted as the

bottom electrode for PZT film and could effective-ly transfer the stress generated through magneto-strictive effect of Ni into piezoelectric PZT film. ThePZT/LNO/Ni ME structure exhibits the ME coeffi-cient, αE31 = 1 V/cm·Oe at very low bias magneticfield of 30 Oe and showed 8.5 V/cm·Oe at magneto-mechanical resonance frequency of 204 kHz corre-sponding to the Ni substrate. These huge ME coef-ficients were interpreted with the improved couplingbetween the magnetostrictive Ni layer and the pie-zoelectric PZT thick film via LNO layer, which waspossible due to similar mechanical impedances ofNi, LNO and PZT.

Curriculum Vitae:

54

Materials

N. Setter : Functions and Structures of Ferroic Domain Walls

Author: Nava Setter, Tomas Sluka, Petr Bednyakov, Leo McGilly, Ludwig Feigle, Xiankui Wei,Petr Yudin, Eugene Mikheev, Igor Stolichnov, and Alexander K. TagantsevEPFL Swiss Federal Institute of Technology (Switzerland)E-Mail: [email protected]: Ultrasonic, nonlinear vibration, phase control, unstable amplitude

Domain walls are fundamental to ferroelectricsand to ferroic materials altogether. They constitu-te interfaces inside a single-phase, mono-crystallinematrix. In comparison to hetero-interfaces such asthose between two distinct materials, domain wallshave additional degrees of freedom as they are mo-bile and can be controlled and modified (i.e. dynami-cally) by external forces: electrical, magnetic and/orstress fields, as well as temperature variation, andcan be annihilated and recreated. We will show ex-perimental and theoretical results on neutral domain

walls and charged domain walls in ferroelectrics andsome of their unexpected properties: unusual elec-trical conductivity of domain walls in insulating ferro-electrics, enhanced piezoelectricity, ferroelectricityinside walls in non-ferroelectric materials, and mani-pulation of magnetic walls by polarization switching.Those results triggered us to search strategies toobtain controlled domain wall structures. Such ’ta-med’ microstructures will be presented. Based onthe above, we attempt to project the potential of ta-med domain walls.

Curriculum Vitae:

55

Table of Contents

M. Takaoka : Study on Torque Generation of the Ultrasonic Motor using a High-SpeedMicroscope

Author: Midori Takaoka, Tomoaki Mashimo, Kazuhiko TerashimaToyohashi University of Technology (Japan)E-Mail: [email protected]: Piezoelectric actuator, travelling wave, elliptical motion, high-speed camera

An ultrasonic motor is a direct-drive actuator thatgenerates high torque without a reduction gear.Such characteristic that achieves high responsiven-ess and zero backlashes are suited for a wide ran-ge of robots such as industrial and home robots. Inthe ultrasonic motor, the stator transfers mechanicalenergy to the rotor by an elliptical motion while a tra-velling wave occurs on the stator. The elliptical mo-tion of the stator is introduced to torque models, butthe actual elliptical motion has not been observed.It is due to that the velocity of the elliptical motion istoo fast and the amplitude of the elliptical motion isvery small. The verification with the actual ellipticalmotion is difficult in the torque models. In this rese-arch, we build a high-speed camera system with mi-croscope (high-speed microscope), the frame rate

of which is over 200,000. The high-speed microsco-pe can capture four frames per cycle for the ultra-sonic motor with the resonant frequency of 40 kHz.Using the high-speed microscope, we succeeded inobserving the elliptical motion of the stator while theultrasonic motor rotates. To know how the ellipticalmotion relates to the ultrasonic motor performance,the relationship between of elliptical motion amplitu-de to the motor torque and rotational speed is clari-fied by experiments. The elliptical motion characteri-stics obtained is discussed to develop a light-weightand high-torque ultrasonic motor; for example, theelliptical motion of a new-developed ultrasonic mo-tor with light materials such as aluminum and titani-um alloys is examined with the measurement of themotor characteristics.

Curriculum Vitae: I was born in 1989 in Japan. I received the Bachelor of Engineering degree inmechanical engineering from Toyohashi University of Technology, Japan, in March 2012. Current-ly, I ams a Graduate Student in the same university.

56

Materials

S. Wada : Piezoelectric Enhancement of Relaxor-based Lead-free Piezoelectric Ceramicsby Complex Nano/Macro Domain Configuration

Author: Satoshi Wada1, Ryuta Mitsui1, Ichiro Fujii1, Shintaro Ueno1, Kouichi Nakashima1,Chikako Moriyoshi2 and Yoshihiro Kuroiwa2

1 University of Yamanashi (Japan) 2 Hiroshima University (Japan)E-Mail: [email protected]: ferroelectrics, nanodomain configuration

It is well known that for the relaxor-based ferro-electrics, the domain configuration is dependent onchemical composition and orientation. This meansthat if relaxor-based lead-free ferroelectrics are pre-pared, it can be expected that they might havehigh piezoelectric performances. Recently, we re-ported that BT − Bi(Zn1/2Ti1/2)O3(BT − BZT )and BT − Bi(Mg1/2Ti1/2)O3 (BT-BMT) were rela-xor ferroelectrics with high Tmax (temperature withmaximum dielectric constant) over 250 ?C. Thus, itis possible to control domain configurations by so-lid solution system between the above relaxors andnormal ferroelectric such as BiFeO3 (BF) with highTc of 830 ?C. In this study, the BT-BMT-BF andBT-BZT-BF system ceramics were prepared usinga conventional solid-state reaction and their crystalstructure and electrical properties were investiga-ted. A single phase of perovskite was prepared forthese ceramics with various compositions exceptfor a few. TEM observation revealed that BT-BMThad no domain configuration while BF-rich cera-

mics had normal rhombohedral domain configura-tions. Moreover, the ceramic with the intermedia-te composition between relaxor and BF had nan-odomain configuration with domain sizes less than50 nm. For the ceramics, the temperature depen-dences of dielectric constants were measured at va-rious frequencies, and the Tmax was determined.As the results, the Tmax increased with increasingBF content, while Tmax decreased with increasingBT content. Finally, their strain vs. electric-field be-haviors were measured, and the relaxors showedtypical electrostrictive behavior while BF-rich cera-mics showed typical butterfly-like ferroelectric strainbehavior. For the ceramics with nanodomain confi-guration, the strain curve with hysteresis-less andhigh slope was clearly observed and the apparentd33 ∗ (= Smax/Emax) from the slope was over 400pC/N. The maximum d33∗ of 850 pC/N was obtainedfor the ceramics with complex nano/macro-domainconfiguration with domain sizes of around 10 nm.

Curriculum Vitae: Satoshi Wada is a professor of Material Science and Technology at University of Yamanashi. His main

research interests include dielectric and piezoelectric nanoparticles, ceramics and single crystals, nano-structure induced enhan-

ced property, and domain engineering in ferroelectric materials. He obtained B.S. degree (1986) in Metallurgy at Ibaraki University,

M.S., (1988) and Ph.D. (1991) degrees in Material Science at Tokyo Institute of Technology. After graduation, he joined the faculty

(assistant professor) at Tokyo University of Agriculture and Technology from 1991 to 1999. During Tokyo University of Agriculture

and Technology, he has held visiting scientist at the Pennsylvania State University from 1996 to 1997. On 1999, he joined the

faculty (assistant professor) at Tokyo institute of Technology, and promoted to an associate professor there on 2000. On 2007,

he joined the faculty (associate professor) at University of Yamanashi and on 2009, promoted to full professor. He has authored

more than 250 publications, 20 patents, and 7 co-authored books in the material science field. He is a member of The American

Ceramic Society, the Materials Research Society, the Ceramics Society of Japan, the Japanese Society of Applied Physics, the

Physical Society of Japan, the Chemical Society of Japan, Catalysis Society of Japan, and the Society of Powder Technology. He

co-organized a symposium at the MS&T06 Conference (2006, Cincinnati), the 8th International Symposium on Ferroic Domains

and Micro- to Nanoscopic Structure (2004, Tsukuba), IUMRS-ICAM 2003 & 2007 (2003, Yokohama & 2007 Tokyo) and the 3rd

International Ceramics Congress (2010, Osaka). He received the Best Presentation Award of MRS-Japan in 1996, the JCerSJ

Best Manuscript Award of the Ceramics Society of Japan in 1997, the Young Scientist Award of Electroceramics Division in 1999,

the PFEIL Award in 2005, the Richard Fulrath Award of the American Ceramics Society in 2007, the JJAP Editorial Contribution

Award of the Japanese Applied Physics Society in 2007, the AEM Award of the Japan AEM Society in 2008 and the CSJ Award

of the Ceramics Society of Japan in 2009.

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Y. Wang : Research on a Linear Piezoelectric Motor with Double Driving Elements

Author: Yin Wang, Weiqing Huang, Hailin Li, Pan SongNanjing University of Aeronautics and Astronautics (China)E-Mail: [email protected]: Linear piezoelectric motor, double driving elements, Multilayer piezoelectric ceramics

A combination of performances with high stiffnessand high resolution is needed in the developmentof positioning stages for machine tools and advan-ced measuring systems. One solution for this is tointegrate bearing, transmission and driving system.So far, piezoelectric actuators have been proven tobe one of the most favorite candidates for this so-lution. Piezoelectric actuators using multilayer pie-zoelectric ceramics arose many interests of resear-chers because of their features of low voltage sup-ply, compact size, stable performance etc. In thisresearch, a novel linear piezoelectric motor usingmultilayer piezoelectric ceramics was proposed. Inthis motor, there are two identical driving elementsand both of them have two groups of multilayer pie-zoelectric ceramics. While respectively applied withtwo sinuous voltage signals with phase difference

of π/2, these two groups of multilayer piezoelectricceramics pushes the driving tip to move with an ellip-tical motion. If two driving element are both excitedwith four sinuous voltage signals with phase diffe-rence of π/2 to each other and two driving tips willalternatively vibrate with elliptical trajectories. A spe-cific design of structure was proposed to clamp twodriving elements to make them touch the slider ofmotor alternatively. In this way, this motor can ope-rate at any driving frequencies and its output speedincreases with the driving frequency linearly, whichmakes the control of this motor very simple. Afterdetail design of a prototype, it was fabricated. Bysome verification tests, the prototype showed desi-red performances and potential of being adopted inhigh precision and high stiffness required systems.

Curriculum Vitae:

58

Materials

J. Wang : The Contact Problem of Hard Contact Materials Linear Ultrasonic Motors

Author: Jinpeng Wang, Jiamei Jin, Chunsheng ZhaoNanjing University of Aeronautics and Astronautics (China)E-Mail: [email protected]: Linear ultrasonic motor, Contact problem, Model, Contact frequency

Aiming at to reduce the effect on positioning ac-curacy by the deformation of the contact interface,high hardness contact materials linear ultrasonicmotor becomes a major driving method of nano-meter precision positioning platform. Hard contactmaterials, such as AL2O3, have been used widelyto improve motion accuracy of linear ultrasonic mo-tors (LUSM). Experimental results show that, for thiskind of LUSM, the contact frequency between thestator and the mover is far less than the frequency ofthe driving signal in some cases. That prevents thevibration energy of the stator from being utilized ful-ly. Nevertheless, almost all existing theoretical mo-dels assume that the stator and mover will come intocontact in each driving signal cycle, resulting in thetheoretical results far different from the actual situa-tion. In order to solve this problem, theoretical ana-lysis and experimental investigation on micro-impactprocesses of hard contact materials linear ultrasonicmotors (HLUSM) are described in this paper. Someparameters, which are closely related to the contactfrequency, have been investigated through model-

ling the high frequency micro-amplitude contact be-haviour in normal direction.This paper focuses on the normal direction (Perpen-dicular to the direction of movement of the slider)contact modeling of HLUSM and experimental pa-rameters analysis for phenomenon that the contactfrequency between the stator and mover is far lessthan the drive frequency of the stator.It is found that the stiffness of the stator supportingspring, the high frequency vibration amplitude of thedriving tip and the low-frequency response amplitu-de and frequency of the stator are important factorsleading to the contact frequency far less than the dri-ving frequency.Experimental parameter analysis shows that thereexists an ideal contact curve which can be obtainedby adjusting the parameters. Meanwhile, the con-tact frequency and the driving frequency of the sta-tor can be coordinated. Experimental results showthat the output power of the linear ultrasonic motoris effectively improved in the ideal contact state. Theefficiency is improved by approximately 50%.

Curriculum Vitae:

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H. B. Xu : Structural and Piezoelectric Properties of the (Na1−xKx)NbO3 NanorodsSynthesized by Hydrothermal Method

Author: Hai Bo Xu1, Mi-Ri Joung1, In-Tae Seo1, Sahn Nahm1, Min-Gyu Kang1,2, Chong-YunKang2, Seok-Jin Yoon2

1 Korea University (South Korea)2 Electronic Materials Center (South Korea)E-Mail: [email protected]: NKN nanorods, lead-free piezoelectric materials, hydrothermal processe, STOsubstrates

(Na1−xKx)NbO3(NKN) nanorods were syn-thesized under various process conditions and theirstructural and piezoelectric properties were investi-gated. The Nb2O5-added (1−y) NaOH−y KOHspecimens were heated at 160 C for 8 h and sub-sequently annealed at various temperatures to formthe NKN nanorods. The NKN nanorods were on-ly synthesized for the specimens with y = 0.15.The homogeneous NKN nanorods having a cubicstructure were formed when the specimens were

annealed at 450 C for 6h. The cubic NKN nano-rods changed to the orthorhombic NKN nanorodswhen the annealed temperature increased to 500

C. In order to measure the piezoelectric constant ofthe NKN nanorods, they were grown on the Nb do-ping SrT iO3 substrates at 160 C for 8h and subse-quently annealed 500 C for 6h. The structural va-riation and piezoelectric properties of the NKN na-norods grown on the Nb doping SrT iO3 substrateswill be also presented in this work.

Curriculum Vitae: Name: HAIBO XU, the master course in electronic material lab from koreauniversity. Researching the piezoelectronic materials and energy harvesting.

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Materials

D. Yamaguchi : Evaluation of Piezoelectric Materials for Transducer at UltralowTemperature

Author: Daisuke Yamaguchi, Takefumi Kanda, Koichi SuzumoriOkayama University (Japan)E-Mail: [email protected]: Ultrasonic motor, Transducer, Ultralow temperature, Piezoelectric material

Ultralow temperature environment provide import-ant measuring condition in advanced scientific re-search area. The ultralow temperature is near theliquid helium temperature, from 20 to 4.2 K. In thecondition, quantum-mechanical effects control thevarious phenomena, for example, superconductivi-ty. Therefore, there are demands for actuators thatcan drive in ultralow temperature conditions.

This paper presents evaluations of a piezoelectri-city of ferroelectric material at ultralow temperature.The piezoelectric performances of piezoelectric ma-terials decrease under ultralow temperature conditi-on. For example, piezoelectricity of zirconate titana-te ceramics under ultralow condition is 20 percentlower than that under room temperature. However,there are a few examples of measuring the piezo-electricity as a material for the transducer at ultralowtemperature. We evaluated the thermal dependenceproperty of the piezoelectricity from room tempera-ture to ultralow temperature.

In this study, we fabricated the measuring sys-

tem which can measure the impedance and pha-se difference at ultralow temperature. To measurethe piezoelectricity of various piezoelectric materi-als under an ultralow temperature, the resonance-antiresonance method was used. The relationshipbetween the piezoelectricity and temperature is eva-luated.

Additionally, we fabricated and evaluated a bolt-clamped Langevin-type transducer for ultrasonicmotor. The transducer is affected by the thermalstress when the temperature is fallen from roomtemperature to ultralow temperature. Our transducerwas designed to prevent the damage from thermalinfluence. The diameter and length of our transdu-cer are 6 and 16 mm, respectively. The transducerhas two piezoelectric rings. To evaluate the vibrationperformance, the admittance of the transducer wasmeasured from room temperature to ultralow tem-perature. We have confirmed that those piezoelec-tric materials are available for the driving source oftransducer at ultralow temperature.

Curriculum Vitae: He received his B. Eng. and M. Eng. from Okayama University, in Japan in2009 and 2011. Since then, he has been a doctoral student at the same university. His currentresearch interests are in piezoelectric actuators and mechatronics.

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Z. Yao : Design method and research progress on linear ultrasonic motors

Author: Zhiyuan Yao, Chunsheng ZhaoNanjing University of Aeronautics and Astronautics (China)E-Mail: [email protected]: Linear ultrasonic motors, Structure design, Bar-structure, Clamping element, Flexiblehinge

Structure evolution of linear ultrasonic motors ab-road is analyzed. It is pointed out that bar-structureand board-structure are simple forms of structures,their vibration efficiency is high and they are the ba-sic effective structure for linear ultrasonic motor sta-tors. It is pointed out that Langevin vibrators withsudden variable cross-sections will cause energyloss of sound wave propagation and a new designmethod based on two Langevin vibrators with con-

tinuous variable cross-sections is proposed. Also adesign method for clamping element that replacesthe spring with flexible hinge is proposed; it can sim-plify stator’s structure and improve its vibration cha-racteristics. A design method of multi-pole for line-ar ultrasonic motor is proposed, which has a mo-re compact structure.Three kinds of linear ultrasonicmotors are described, of which structure is simple,operation is smooth and output efficiency is high.

Curriculum Vitae: Zhiyuan Yao, Ph.D. degree at Southeast University, is currently a professor atNanjing University of Aeronautics and Astronautics. He is the Vibration, Measurement & Diagno-sisManaging Editor of the Editorial Board, deputy editor-in-chief.He engages in structural vibration analysis and dynamic modeling. His research involved struc-ture design, the contact friction analysis and structural dynamics modeling for ultrasonic motors.He developed a variety of linear ultrasonic motors, and relative industrial applications. He hascompeted (as the program president) and is carrying out a National Key Basic Research andDevelopment Program (973 Program) issues, a major national scientific instruments developedspecial issue, two National Natural Science Foundation of China, a Natural Science Foundationof Jiangsu Province. Now he applied for 15 national invention patents, in which 8 of them areauthorized; he has published more than 30 research papers.

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C. Chen : A Novel Linear Ultrasonic Motor Based on Shear Vibration Mode

Author: Chao Chen, Yiping Wang, Haipeng Chen, Mingsen GuoNanjing University of Aeronautics and Astronautics (China)E-Mail: [email protected]: converse piezoelectric effect, shear vibration, linear, ultrasonic motor

It is well known that piezoelectric effect with she-ar strain mode, i.e., the d15 effect is very attracti-ve for the applications for piezoelectric actuators,and the shear piezoelectric coefficient d15 is hig-her than d31 and d33. In this paper a novel linearultrasonic motor, which is actuated based on she-ar stress mode (d15 converse piezoelectric effect),is presented. Firstly shear vibration mode of piezo-electric stator is analyzed. The elliptical trajectory ofdriving point on the stator induced by shear vibrationmodes is discussed. Then the dynamical analysis

of piezoelectric stator is carried out, and the com-plete structure design for the proposed linear microultrasonic motor ultrasonic motor is given. Finallythe prototype is manufactured, and the mode expe-riment of piezoelectric stator is conducted. The ex-perimental results show that the calculated vibrati-on modes can be excited successfully. Moreover theprototype performance, including frequency-speed,voltage-speed, and phase-speed curve, are experi-mentally measured.

Curriculum Vitae: Chen Chao *received the B.Eng. and M.Eng. degrees in mechanical and elec-tronic engineering from the North University of China, Taiyuan, China, in 1999 and 2002, respec-tively, and the Ph.D. degree in mechanical design and theory from Nanjing University of Aero-nautics and Astronautics (NUAA), Nanjing, China, in 2005. From 2005 to 2008, he worked in thePrecision Driving Laboratory (PDL), NUAA, as a Lecturer. Since 2008, he has been an AssociateProfessor of PDL, NUAA. His research interests are design and theoretical modeling technolo-gies of piezoelectric actuators. He has published more than twenty papers about piezoelectricactuators.

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T. Cheng : Proposal and Development of Ultrasonic Locking Mechanism

Author: Tinghai Cheng, Han Gao, Gang BaoHarbin Institute of Technology (China)E-Mail: [email protected]: Ultrasonic Locking Mechanism (ULM), Cylindrical Bending Actuator, Friction Reduc-tion, Travelling Wave, Screw Thread, Self-Locking

Ultrasonic motor (USM) realizes the transitionfrom electric energy to mechanical energy by ex-citing the vibrator to gain a micro vibration in ultra-sonic frequency range and has some advantagessuch as large torque at low velocity, quick dynamicresponse, high position accuracy, and so on. Howe-ver, the working principle of USM demonstrates thatthere are two transformation processes of energy,one is the input electric energy to mechanical ener-gy of stator, and the other is the mechanical energyof stator to rotor by friction coupling. So, one of thesignificant demerits of USM is the low efficiency andusually applied in low load condition.

A novel mechanism described as ultrasoniclocking mechanism (ULM) comprising an ultrasonicactuator and screw shaft is proposed. The orthogo-nal bending vibration modes of cylindrical ultrasonicactuator are excitated to generate a travelling wavepropagating along the internal thread surface. Thetravelling wave mainly produces a movement trend

between ultrasonic actuator and screw shaft not thedriving force for ULM. Furthermore, based on thefriction reduction effect induced by ultrasonic vibra-tion, the friction coefficient between the ultrasonicactuator and screw shaft is reduced and the screwself-locking status can be transformed and control-led.

A prototype of ULM was developed and tested un-der the mass load. Testing results indicate that ULMhas a different load characteristic with USM. Speci-fically, when the mass load exceeds a certain valuedefined as inflection load, the output speed will gaina steady value named as steady speed. The steadyspeed increases as the exciting voltage increases,while the inflection load has no direct relationship toexciting voltage. It is demonstrates that ULM has theadvantages of simple structure, large bearing capa-city, low driving voltage, and could be applied in pre-cision positioning, protecting mechanism, and velo-city control system.

Curriculum Vitae: Ting-hai CHENG received the B.S. and M.S. degrees in mechanical enginee-ring from Harbin Institute of Technology (HIT), China, in 2006 and 2008, respectively. Since 2008,he has been a Ph.D. candidate in HIT and his research interests include piezoelectric devices:ultrasonic motors (USM) and ultrasonic locking mechanism (ULM), etc.

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F. Fang : Phase Fragility and Mechatronic Reliability for Pb(Mg1/3Nb2/3)O3− PbT iO3Ferroelectric Single Crystals at the Morphotropic Phase Boundary

Author: Fei Fang1, X. Luo1, H. Qing1, F. C. Zhang1, W. Yang2

1 Tsinghua University (China)2 Zhejiang University (China)E-Mail: [email protected]: Piezoelectric single crystals, polarization rotation, mechatronic reliability

Single crystals of (1 − x)(PMN − xPT ) and(1 − x)Pb(Zn1/3Nb2/3)O3 − xPbT iO3(PZN −xPT ) near their morphotropic phase boundaries(MPBs) are under extensive investigations for theirextraordinary high dielectric and piezoelectric be-havior. Applications of those single crystals causedbreakthrough in ultrasonic transducer materials anddevices. For applications such as transducers, ac-tuators and memory devices, ferroelectrics are ex-pected to experience static or alternating electricfields. As it is well known, ferroelectric materials arefragile, with fracture toughness typically in the orderof . That weakness often leads to various failuresin applications involving electric loading. The failuremodes include the fracture under an intensive elec-tric field, and the fatigue crack propagation underalternating electric field. Both modes degrade theperformance for ferroelectric devices [1]. As differentfrom the tetragonal (T) ferroelectric materials, suchas BaTiO3 and Pb(ZrT i)O3, the domain structu-res of PMN-PT around the MPB are versatile and

rather intricate, depending sensitively on the compo-sition variation, orientation and previous loading his-tory. Monoclinic phases such as MA,MB,MC , andorthorhombic (O) phases were reported in PMN-PT single crystals near MPB. In this presentation,we will focus on three aspects on the PMN-PT sin-gle crystals which are located at MPB. Firstly, in-situobservations of the domain evolution and the pola-rization rotation under bipolar cyclic and static elec-tric fields are presented for both [001]-oriented and[101]-oriented PMN-PT single crystals. Polarizationrotation linking MC , T (orMB, O) and R phases arerevealed for [001] (or [101])-oriented PMN-PT singlecrystals. Secondly, investigations on electric field-induced fatigue crack propagation are presented,as well as the orientation effect on the crack pro-pagation behavior. Thirdly, polarization degradationupon cyclic electric loadings, and the role of micro-cracking and phase transition on the polarization ispresented.

Curriculum Vitae: Dr. Fei Fang is currently a Full Professor in School of Aerospace, TsinghuaUniversity, Beijing, China. She earned her Ph. D in Materials Science and Engineering in 1996from Tsinghua University. Then, she joined the university as a faculty member in Departmentof Engineering Mechanics, pursing interdisciplinary research on Materials Science and SolidMechanics. From 1999 to 2000, she worked as a visiting professor in Materials Research La-boratory in The Pennsylvania State University. During her professional life, Dr. Fei Fang mainlyfocused on the electro-mechanical behavior and mechatronic reliability of ferroelectric ceramics,electro-active polymer films, and high-performance ferroelectric single crystals. She has autho-red more than 50 scientific articles in peer-reviewed journals, and delivered many invited talksin international conferences. Her current research interests include the domain switching andelectro-mechanical-magnetic coupling behaviors for multiferroic materials, as well as the hightemperature mechanical behavior of aerospace materials and structures.

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Y. Fujiuchi : Domain Orientation Controlled KN Family Piezoelectric Materials withHydrothermal Powders

Author: Yukiko Fujiuchi, Takafumi Maeda, Takeshi MoritaUniversity of Tokyo (Japan)E-Mail: [email protected]: Hydrothermal synthesis method, KNbO3, (K, Na)NbO3

In recent years, concern about an environmen-tal problem is increasing worldwide. Therefore, inthe field of piezoelectric materials, research anddevelopment of lead-free piezoelectric materialsare actively performed. Especially, KNbO3 and(K,Na)NbO3 ceramics get a lot of attention, dueto their high piezoelectric property [1]. Additionally,it has been reported that the KNbO3 single crystalshows a high electromechanical coupling coefficientin surface acoustic wave excitation; therefore thismaterial is expected as a new piezoelectric singlecrystal for SAW devices [2]. Piezoelectric single cry-stal has high piezoelectric constant than ceramicsbecause there are no crystal boundary. So, the do-main orientation control of ceramics is useful for theimprovement piezoelectric characteristics. Basedon the above mentioned background, we proposednew fabrication process realizing the domain orien-ted KN family piezoelectric materials.

In this study, the domain orientation controlledKNN and KN materials were fabricated using a sin-

gle crystal SrTiO3 (100) substrate. A hydrothermalsynthesis method is a technique promoting a che-mical reaction using the water vapor pressure underhigh temperature and high pressure. As source ma-terials, the hydrothermally synthesized powders we-re utilized because of their high quality and purity.These powders were put on STO substrate and we-re heat-treated at high temperature close to the mel-ting point. After being cooled over tens of hours, thedomain orientation was controlled. The XRD mea-surement, the electric property measurements, thesurface topography and the piezoelectric force map-ping were carried out. Both in KN and KNN films, in-fluences of STO were confirmed. In the case of KNNfilm, mechanical Q value was increased after the do-main orientation control. In KN film, it was confirmedthere was no grain boundary and observed clear fer-roelectric domain patterns by using PFM.

[1] T.R.Shrout and S.J.Zhang J.Electroceram.Vol19(2007) pp.111-124[2] H.Odagawa and K.Yamanouchi Jpn.J.Appl.phys.Vol37(1998) pp.2929-2932

Curriculum Vitae:

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W. Huang : Research on an S-shape Linear Piezoelectric Motor

Author: Weiqing Huang, Yin Wang, Sheng Zhang, Pan SongNanjing University of Aeronautics and Astronautics (China)E-Mail: [email protected]: Linear piezoelectric motor, Inchworm, Multilayer piezoelectric ceramics

Peristalsis type precision drivers adopt the lami-nated piezoelectric ceramics as actuator element,they have the characteristics of low voltage driver,direct output the large deformation, and avoid thestrongly nonlinear output performance caused bythe resonance, However, a problem in the motor de-velopment is the larger spacing between the clampfeet, which requires higher processing accuracy ofthe promoter and makes the structure of systemcomplicated, in addition, the piezoelectric motor ba-sed on the principle of the inchworm adjusts theclamping force by adjusting the pre-tightening for-ce or spacing between the stator and the mover ,and therefore they don’t have the self-locking ability.In this paper, we proposed an S-shape linear piezo-electric motor, as a classification of the piezoelectricstepper precision drive, which not only has the abo-ve advantages, but has self-locking function, whichreduces the cost of the motor and achieves morestable performance. The structure of the S-shapelinear piezoelectric motor includes a stator and amover. The stator consists of a combination of S-shaped displacement conversion mechanism, multi-layer piezoelectric ceramics and clamping support.

The S-shaped displacement conversion mechanismconsists of three displacement conversion mecha-nism layers connecting to each other end to end.The upper and lower displacement conversion me-chanism plays the role of enlarging the deformati-on of multilayer piezoelectric ceramics. The middlelayer of conversion mechanism preload two sets ofmultilayer piezoelectric ceramics and clamping sup-port is placed between the two sets of multilayerpiezoelectric ceramics. The working principle of theinchworm-type piezoelectric linear actuator is analy-zed, and the dynamic model of the actuator is esta-blished. Based on the analysis of the actuator’s sta-tor, the output performance of proposed actuator isanalyzed, experimental results show that the outputdisplacement of the actuator is stable, and the dis-placement for single step is 0.6µm when the actua-ting voltage is 100 V. The velocity and accelerati-on properties of the linear actuator are tested. Ac-cording to the testing results, the dynamic responseperformance of the actuator is analyzed. The experi-mental results show that the proposed piezoelectriclinear actuator has good dynamic performance andmotion stability.

Curriculum Vitae:

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M. Hunstig : High-Velocity Slip-Slip Operation of Piezoelectric Inertia Motors-Experimental Validation

Author: Matthias Hunstig, Tobias Hemsel, Walter SextroUniversity of Paderborn(Germany)E-Mail: [email protected]: piezoelectric inertia motor, stick-slip motor, driving signal

Piezoelectric inertia motors, also known as ”stick-slip-drives”, use the inertia of a body to drive it bymeans of a friction contact in a series of small steps.These steps are often assumed to involve stictionand sliding, but inertia motors can also operate wi-thout phases of stiction. As shown by the authorsin previous publications, such ”slip-slip” operationallows higher velocities and smoother movementsthan classic ”stick-slip” operation. It can be realizedwith a variety of driving signals.

One very promising drive signal for inertia motorsis the superposition of multiple sinusoidal signals(”harmonics”). Such signals contain only a few fre-quencies and thus do not require high-bandwidthactuators. With an appropriately designed transdu-cer, actuation with such signals can also make useof resonant effects. A detailed theoretical investi-

gation of an inertia motor driven with superposedsinusoidal signals has recently been performed bythe authors. In a motor with limited bandwidth, atrade-off between a high drive frequency and a lar-ge number of harmonics has to be made.

In this contribution, a short summary of the theo-retical results is given before the findings are put intopractice and validated using a specially constructedmotor which can cover a suitable range of funda-mental frequencies and numbers of harmonics. Theresults confirm the theoretical result that a signalwith high fundamental frequency and consisting oftwo superposed sine waves, as already realised insome resonant motors in literature, leads to the hig-hest velocity and the smoothest motion. This resultis very useful for further developments of piezoelec-tric inertia motors.

Curriculum Vitae: Matthias Hunstig studied mechanical engineering at the University of Pader-born and graduated with distinction at the end of 2007. Since then he is a research assistantat the chair for mechatronics and dynamics at the University of Paderborn. He started workingon different piezoelectric systems as a student, developing energy harvesters and active vibra-tion damping systems. His current main research interests are piezoelectric drives and energyharvesting.

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H.-W. Kang : Multi-layered Piezoelectric Earthworm Type Actuator

Author: Hyung-Won Kang1,2, Seung-Ho Han1, Hyeung-Gyu Lee1, Jung-Wook Park21 Korea Electronics Technology Institute (South Korea)1 School of Electrical and electronic Engineering (South Korea)E-Mail: [email protected]: multi-layered earthworm type actuator

In accordance with the trend of becoming smal-ler size in the electronic device, miniaturization ofelectronic components to be inserted is essential. Inaddition, electronic components can be made smal-ler using the piezoelectric effect. From that point ofview, it is appropriate to use piezoelectric actuator inelectronic devices that require precise position con-trol and high generated force.

In this study, we propose multi-layered ear-thworm type actuator. Compared with multi-layeredinchworm type actuator, driving signals of ear-thworm type actuator are very simple. We measu-red generated force and moving speed. The resultspresented in this study provide possibility of piezo-electric actuator to be used.

Curriculum Vitae: Hyung-Won Kang received the B.S. in 1997 and M.S. degree in 1999 fromYonsei University, Seoul, Korea and is researching piezoelectric components at Yonsei Universityfor Ph.D. He worked for Samwha Capacitor Co., Ltd. and Daewoo electronics Co., Ltd. He is a se-nior researcher at Korea Electronics Technology Institute (KETI) from 2004. His current researchinterests include development of piezoelectric actuators and energy harvesting systems.

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R. Kashima : Design of a Junction in Noncontact Ultrasonic Transportation System

Author: Ryota Kashima1, Soichi Murakami2, Daisuke Koyama1, Kentaro Nakamura2, MamiMatsukawa1

1 Doshisha University (Japan)2 Tokyo Institute of Technology (Japan)E-Mail: [email protected]: noncontact ultrasonic transportation technique

Our group has been investigating the noncon-tact ultrasonic transportation technique of small ob-jects over long distances using a flexural vibratingplate and reflector. By the ultrasonic standing-wavefield generated between the two plates, small partic-les could be trapped and manipulated with a linearand a circular trajectory. In this report, a junction ofthe transportation paths enabling to catch and ejectsmall objects was investigated. A 0.5-mm-thick alu-minum circular plate with a diameter of 30 mm wasemployed as a vibrating plate. A 0.5-mm-thick piezo-electric ring (inner diameter: 8 mm; outer diameter:14 mm) was attached to the vibrating plate by epo-xy. A reflector was installed parallel to the vibratorwith a distance of approximately 4 mm to genera-te an acoustic standing wave in air between them.Resonance modes of the acoustic field in a disc ca-vity between the vibrator and reflector were calcula-

ted theoretically. The distribution of the sound pres-sure amplitude and the acoustic radiation force inthe cavity were also calculated using finite elementanalysis. The flexural vibration mode with one nodalcircle and four nodal lines at 47.8 kHz ((1,4) mo-de) and two nodal circles and three nodal lines at64.9 kHz ((2,3) mode) were used to trap and ejectsmall particles, respectively. The electrodes of pie-zoelectric ring were divided into 18 pieces to gene-rate these vibration modes. On the prototype, the re-sonance frequencies of (1,4) and (2,3) modes were45.4 and 58.1 kHz, respectively. The ejection direc-tion of the trapped particle could be controlled to theradius direction (0) and 45 by the driving conditionof the PZT ring. The transportation velocity of trap-ped polystyrene particle with a diameter of 2 mmand weight of 0.3 mg was 812 mm/s and then thethrust force was 24 µN.

Curriculum Vitae:

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F. Li : Ultrahigh Superelastic and Actuation Strains in BaTiO3 Crystals by ReversibleElectromechanical Domain Switching

Author: Faxin Li1, Yingwei Li1, Xiaobing Ren2, Haosu Luo3, Daining Fang1

1 Peking University (China)2 National Institute for Materials Science (Japan)3 Chinese Academy of Sciences (China)E-Mail: [email protected]: domain switching, superelasticity, actuation, barium titanate

Superelasticity (SE) had been observed in shapememory alloys and other smart materials includingthe relaxor ferroelectrics via reversible phase trans-formation, while it has never been realized in nor-mal ferroelectrics. Theoretically, SE could appearin polyaxial ferroelectrics via reversible ferroelasticdomain switching but should be under a bias elec-tric field because different domains are by defaultenergetically identical. Attempts to realize SE in fer-roelectric ceramics in this way had been conductedand never successful, probably because the energybarrier for domain switching is very large in cera-mics. On the other hand, large actuation strains upto ∼0.8% through reversible domain switching hadbeen realized in ferroelectric crystals by electric fieldwith prestress or via point-defects mediating. Whileutility of these large strains still has some problemdue to the required large bipolar field or the relaxa-

tion of the point defects.

In this work, for the first time, we realized bothultrahigh superelastic and actuation strain in a spe-cially poled BaTiO3 crystal under uni-axial electro-mechanical loading. During uni-axial compressiondepolarization with a dc bias electric field (Edc),SE can appear when Edc is between 200 and600V/mm. The largest SE strain is up to 0.85% andit can be tunable by the applied electric field, whichis very promising for advanced damping applicati-ons. When keeping the compression and makingthe unipolar electric field cycling, an actuation strainof 0.93% has been obtained at 800V/mm. The ob-tained ultrahigh superelastic and actuation strains inBaTiO3 crystals are both caused by reversible 900domain switching which can be depicted by an uni-fied incremental switching criterion.

Curriculum Vitae: Faxin Li is now a Professor at College of Engineering, Peking University, Bei-jing, China. He got PhD on solid mechanics from Tsinghua University, Beijing, China on July2004. From Mar.2005 to July 2007, he worked as a postdoctoral fellow at the University of Bri-tish Columbia, Vancouver, Canada. Since Oct 2007, he worked as a faculty member at Collegeof Engineering, Peking University. His research interests include deformation and reliability ofsmart materials and structures, nanomechanical characterization using atomic force microscopy,and medical elastography. He had authored more than 40 journal papers on smart materials andstructures since 2003.

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Y. Shi : Linear Piezoelectric Actuator for Precision Linear Positioning

Author: Yunlai Shi, Chunsheng ZhaoNanjing University of Aeronautics and Astronautics (China)E-Mail: [email protected]: Precision positioning, Ultrasonic, Piezoelectric actuator

This paper describes the development of a new li-near piezoelectric actuator for linear precision trans-lation. First, the drive principle of the linear piezo-electric actuator is described. The use of the sym-metric modal and anti-symmetric modal of the trans-ducer (stator) realizes the function of driving the sli-der pressed on the driving feet twice in one cycle.Second, the transient dynamic behavior of the line-

ar piezoelectric actuator is analyzed using finite ele-ment method. Third, the structure of the two-degreeposition stage system is described in detail. Finally,the characteristics of the two-degree positioning sta-ge are investigated. The experiment results confirmthat the developed stage can be controlled to thetarget position plus or minus < 0.5µm for a travelingdistance of 50 mm in the closed-loop condition.

Curriculum Vitae: Yunlai Shi received his B.S. degree in Heat Treatment from Shandong Uni-versity of Technology in 1999. From 1999 to 2004, he was an engineer in Yankuang Group ltd.From 2004 to 2011, he studied mechanical design and theory in Nanjing University of Aeronau-tics and Astronautics and obtained his PHD degree with the best academic records. Now, He is ateacher of Nanjing University of Aeronautics and Astronautics. His research interests are mainlypiezoelectric actuators and their applications.

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E. Teidelt : Nano-Positioning Stick-Slip Motors: Numerical Simulation and PerformanceImprovements Using the Method of Reduction of Dimensionality

Author: Elena Teidelt, Ha X. Nguyen, Valentin L. PopovBerlin University of Technology (Germany)E-Mail: [email protected]: stick-slip drive

Piezoelectric motors using the stick-slip principleare standard technical devices. However, their phy-sical description remains case specific and is oftenbased on multiple empirical parameters. In this talk,we will describe the method of reduction of dimen-sionality and how it can be used to describe tangen-tial contacts. Considering the nano-positioning devi-ce Ramona, we will exemplarily show how this me-thod is used to describe the movement of the run-ner of this motor. The runner is driven by six piezoactuators, rotating six ruby hemispheres. Differentmodels describing the sphere-runner interaction are

presented. Furthermore the modelling of the contactas rough or smooth will be considered. All numericalresults of the specified models will be compared withexperimental data. A special focus lies on the cha-racterization of the so called 0-Amplitude, the ampli-tude of the actuators excitation under which no netmovement of the runner is yet detectable. In addi-tion, we will propose a simple model of the runneractuator interaction, which not only describes theoverall movement of the runner, but also elegantlyproposes the signal shaping method to increase theperformance of stick-slip drive.

Curriculum Vitae: Elena Teidelt studied engineering science at the Technische Universitat Berlin,Germany. During her studies she was teaching assistant, as well as a research assistant forthe DFG Research Center Matheon, where she worked on an industrial implementation of aneigenvalue solver for large sparse matrices. After finishing her Diploma in 2009 she started hernew research at the Institute of Mechanics at the Technische Universitat Berlin in the Departmenton System Dynamics and Friction Physics. Here her main research topic is the dynamic tangentialcontact under the influence of vibration. In particular, she investigated the influence of ultrasonicvibrations on friction and is now modelling micro contacts describing stick-slip drives.

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D. O. Uribe : Piezoelectric Tactile Sensor using Multisine Excitation for Differentiation ofBiological Tissues and Phantoms

Author: David Oliva Uribe1, Johan Schoukens1 and Jorg Wallaschek21 Vrije Universiteit Brussel (Belgium)2 Leibniz Universitat Hannover (Germany)E-Mail: [email protected]: Tactile Sensor, Tissue Differentiation, Multisine Excitation

Brain tumor surgery is a complex task that reliescritically on a correct identification of tumor boun-daries based on visual and tactile impressions per-formed by neurosurgeons. The information of thepre-operative 3D coordinates of the tumor providedby imaging techniques (e.g. Magnetic ResonanceImaging) will differ from the real position at the mo-ment the skull is opened due to brain shift pheno-menon. Thus, the development of assisting tools forintra-operative tumor delineation and tumor resec-tion in neurosurgery is vital to increase the safetyand accuracy of this procedure. In this contributi-on we report our efforts developing a piezoelectrictactile sensor using a piezoelectric bimorph whereresults of experiments carried out on tissue gelatinphantoms (with slightly differences in their mechani-cal properties) shown that is feasible to differentiate

them by the evaluation of the frequency responsefunction. Moreover, the use of broadband multisineexcitations instead of standard frequency sweep hasled to an important improvement in measurement ti-me. In addition, it is discussed the design and selec-tion of optimal excitation signals based on multisinethat provide useful information to construct a validmodel capable to estimate the mechanical parame-ters of biological tissues and soft materials. In practi-ce, all biological tissues, including gelatin phantomsbehave as a nonlinear viscoelastic material. Experi-ments using several contact forces were carried outto determine the influence of the contact force on thedifferentiation process. Measurements results sho-wed that nonlinear distortions are present but still alinear model can be used to differentiate phantomswith high accuracy.

Curriculum Vitae: David Oliva Uribe was born on May 24th 1975, Mexico City, Mexico. His rese-arch interests are in the field of system identification techniques for piezoelectric transducers, inparticular the characterization of biological tissues using tactile sensors in medical applications.He graduated with Honors in Electronic and Communication Engineering in 1997 and obtained aMaster in Sciences with Specialization in Manufacturing Systems in 2000, both from Tecnologicode Monterrey in Mexico City. From April 2007 to December 2010 he worked as research assistantat the Institute of Dynamics and Vibrations Research from the Leibniz University of Hannover. Sin-ce January 2011, he joined the Department ELEC, Vrije Universiteit Brussel, where he is workingtoward a joint PhD degree.

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L. Wang : A Piezoelectric Tracked Vehicle with Potential Application to PlanetaryExploration

Author: Liang Wang, Jiamei Jin, Chong HuangNanjing University of Aeronautics and Astronautics (China)E-Mail: [email protected]: rover vehicle, tracked vehicle, piezoelectric driving, mode, friction force

Abstract: A piezoelectric driving method for rovervehicles is proposed in this paper. Employing thismethod, a tracked vehicle driven by friction forcesfrom a frame mounted with piezoelectric elementswas developed. The vehicle is designed with no dri-ver sprocket, no idler-wheel and no supporting bogiewheels, and the vehicle thus requires no lubricationand has potential application in planetary explorati-on. The vehicle is driven by a pair of piezoelectric vi-brators, each of which is composed of four annularparts jointed by beams adhered with piezoelectricelements. The tracks are set along the outlet sur-faces of the annular parts by means of track tensi-on. Traveling rotating waves are generated by pie-zoelectric transducers in the annular parts along thebeams, and they create microscopic elliptical moti-ons at the interface of the tracks. The microscopicelliptical motions from the piezoelectric transducers

drive the track vehicle to move. There are (1) no sli-ders or bearings in the tracked vehicle, which eli-minates many of the disadvantages associated withthe high internal friction and mechanical complexityof traditional tracks, (2) no bogie wheels, which re-duces the internal friction losses that are characteri-stic of most traditional tracked vehicles, (3) no tracklinks, which eliminates the catastrophic link breaka-ge problem, and (4) no lubricants, which eliminatesthe problem of lubricant volatilization and deflation.Finite elements analysis was carried out to verifythe operation principle using commercial softwareANSYS. Piezoelectric transducers were fabricated,assembled and tested to validate the concepts ofthe proposed rover vehicle and confirm the simulati-on results. A prototype vehicle with mass of 0.57 kgmoves at a speed of 4.3 mm/s at a driving voltageof 250 V and operating frequency of 65.53 kHz.

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L. Yang : Flexible Supporting and Fixing Method for Hybrid Ultrasonic Motor UsingLongitudinal and Torsional Vibration Modes

Author: Lin Yang, Chunsheng ZhaoNanjing University of Aeronautics and Astronautics (China)E-Mail: [email protected]: Flexible, ultrasonic motor, Longitudinal and Torsional, supporting and fixing

A new flexible supporting and fixing method forhybrid ultrasonic motor using longitudinal and tor-sional vibration modes is presented. A motor casingis used to support and fix the motor, which has dualconcentric bearings in opposite shell sides and a fi-xing column. The axis of the motor has two extendedparts outside the both sides of the motor. Once themotor has been assembled completly, the two ex-tended parts of the motor axis will be inserted intothe concentric bearings, which supports the motorand restricts the x and y degrees of freedom(DOF)

of the motor. The motor has a flexible fixing piecewhich placed near the piezoelectric ceramics, the fi-xing piece is thin enough to have flexibility and it isfixed on the fixing column with glue, which restrictsthe z DOF and rotating DOF of the motor. The expe-riment results show that the motor working frequen-cy with supporting and fixing changes little, compa-red with the frequency without the supporting andfixing, and the motor can works smoothly and stea-dily.

Curriculum Vitae: Lin Yang, male, born in 1981, lecturer. He received a Doctorate in NUAAin China in 2010. The research fields include high-power ultrasonic motors and the ultrasonicmotors used in space environment.

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Energie Harvesting

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A. Affanni : Low-Power Energy Harvesting Solutions for Wiegand Transducers

Author: S. Saggini1, F. Ongaro1, L. Corradini2, A. Affanni11 University of Udine (Italy)2 University of Padova (Italy)E-Mail: [email protected]: Wiegand magnetic sensors

This paper discusses the use of Wiegand ma-gnetic sensors as energy harvesters for poweringlow-power electronic equipment. Sensors based onthe Wiegand effect [1] are employed in a numberof everyday life applications, including pulse gene-rators in absolute encoders for highperformancemotion control [2], as well as keycard door locksfor electronic entry systems relying on the Wiegandprotocol [3]. The core of a Wiegand sensor consistsof a ferromagnetic material such as Vicalloy [4] ha-ving non-uniform magnetic properties which enablea sharp magnetic hysteresis to occur. As depictedin Fig. 1, Wiegand device typically releases a 10µs voltage pulse several volts wide when subjectto an external, time-varying magnetic field. Whenoptimally loaded, a Wiegand device is capable ofup to 100 nJ/pulse delivered energy. Due to thesharpness of the magnetic transition, pulse gene-ration occurs regardless of how slow the magneticfield variation is, an attractive feature that enablesits use in energy harvesting scenarios even whenlow-frequency sources are considered. Aim of thiswork is to investigate the use of Wiegand sensorsas small-scale energy sources, and propose a low-power harvesting circuit capable of efficiently inter-

facing the sensor with a fixed DC bus with a voltagerange typical of 3.3V or 5V as reported in Fig. 2.

This work identifies the theoretical model of thiskind of generator. An exact model of this generatorallows the definition of the maximum power availa-ble form each pulse and the harvester optimization.Based on such considerations, energy harvestingcircuits are then proposed and their operation dis-cussed in detail both theoretically and via simulationanalysis. Experimental results are provided suppor-ting the developed theoretical framework and the ef-fectiveness of the proposed implementation.

[1] J.R. Wiegand et al., ”‘Bistable Magnetic Device,”’U.S. Patent No. 3,820,090, Jun. 1974[2] ”‘Innovative Encoders for Demanding Appli-cations,”’ POSITAL-FRABA, White Paper. Availa-ble: http://ebookbrowse.com/absoluteencoders-context-technology-magnetic-white-paper-datacontent-pdf-d319925267[3] ”‘Wiegand Readers,”’ Nothern Computers Inc., Tech-nical Datasheet. Available:http://www.honeywellaccess.com/documents/TD5027rev0500.pdf

[4] J.R.Wiegand,”’SwitchableMagneticDevice,”’U.S.PatentNo.4,247,601, Jan. 1981

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W. Al-Ashtari : Characteristics of Piezoelectric Harvesters in Autonomous Systems

Author: Waleed Al-Ashtari, Matthias Hunstig, Tobias Hemsel, Walter SextroUniversity of Paderborn (Germany)E-Mail: [email protected]: energy harvesting, autonomous systems, piezoelectric generators

Energy harvesting is the process of convertingambient energy into useful electrical energy. Forabout a decade, the challenge has been to de-sign autonomous systems which fulfil their task andpower themselves from available ambient energy.Piezoelectric harvesters have generally receivedmost attention concerning their potential to powersuch systems.

The basic configuration of an autonomous sys-tem typically contains three elements in addition tothe piezoelectric harvester: a full-wave rectifier, areservoir capacitor and an electronic device perfor-ming the primary task. Throughout literature manypublications can be found in which the DC voltageacross the electronic device is calculated using dif-ferent models. All models assume that the voltagegenerated by the piezoelectric harvester has a si-nusoidal form. In real applications, this assumptioncan be inaccurate because the form of the genera-

ted voltage signal is influenced by the rectificationprocess and by the connected capacitor and load.

In this contribution, a model describing the ope-ration of the complete autonomous system is de-rived and its operation is analyzed. The modeledsystem is also investigated experimentally and agood agreement between theoretical and experi-mental results is found: In steady-state operation,the piezoelectric harvester experiences two alterna-ting load conditions due to the rectification process.This effect can considerably impair the harvesteroperation, especially if the connected electrical loadis small. As well it can prevent the autonomous sys-tem from functioning if the electrical elements arenot properly matched. Furthermore the results showthat such an autonomous system works best if itis connected to a large load and excited by a fre-quency matching the anti-resonance frequency ofthe piezoelectric harvester.

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K. H. Baek : Study on Energy Storage Device for the Impact-Based Piezoelectric EnergyHarvesting System

Author: Ki Hwan Baek, Jeong Hun Kim, Min Sik Woo, Daniel Song, Se Bin Kim, Tae Hyun SungHanyang University (South Korea)E-Mail: [email protected]: Piezoelectric Energy Harvesting (PEH), impact-based system, storage devices

The interest about the piezoelectric energy har-vesting system has been increased recently. A pie-zoelectric energy harvesting system consists ofthree major parts: energy source, harvesting cir-cuit, and storage device. In the energy source part,there are two methods for generating the power.One way is using the vibrational energy and anotheris through the impact energy to the piezoelectricmaterial. There was a previous study on analyzingstorage devices for vibrational piezoelectric energyharvesting system [1]. However, analysis on storagedevices for impact-based piezoelectric energy har-vesting system has not yet been studied.

The impact-based system generates higherpower than vibration system. Therefore, choosingthe energy storage device matching the impact-based piezoelectric energy harvesting system isimportant in order to harvest higher power. Thispaper provides the proper energy storage devi-ce for piezoelectric energy harvesting system fromimpact-based system. Among the many storage de-vices, supercapacitor, lithium ion battery and nickel

cadmium battery were selected. The most efficientstorage device for impact-based piezoelectric ener-gy harvesting was selected through analyzing thetransferred power to storage device by changingvoltage ratio.

Additional experiment was held for vibration sys-tem for same storage devices used in impact-basedsystem. The result of vibration system and impact-based system was compared. The compared resultsshowed that higher output power was observed inimpact-based system. Since the impact-based sys-tem generated much higher output power, additionalcontrol circuitry can be applied in order to improvecharging efficiency.

The selected storage device from this study couldbe used in a variety of fields that requires higherpower in the piezoelectric energy harvesting sys-tem.[1] M. J. Guan and W. H. Liao, ”Characteristics of EnergyStorage Devices in Piezoelectric Energy Harvesting Sys-tems,” Journal of Intelligent Material Systems and Struc-tures, Vol. 00-2007, July 2007.

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Y. Bai : Fabrication and Investigation of Free-standing Piezoelectric Thick-film Cantileversfor Energy Harvesting Applications

Author: Yang Bai, Tim W Button University of Birmingham (United Kingdom)E-Mail: [email protected]: piezoelectric, free-standing, thick-film, wideband, wind

The rapid growth of wireless and self-poweredsensor technologies necessitates the correspondingdevelopment of ”micro” energy harvesting, whichaims to capture and transfer usable energy (at themW level) from the environment for the devices. Vi-bration energy in the environment has drawn muchattention since it is the easiest to obtain and existsalmost everywhere. For the purpose of convertingvibration energy into usable electrical energy forlow-power sensor networks, piezoelectric materi-als are potentially ideal candidates with their higherenergy conversion compared to magnetic and elec-trostatic materials.

Most research involving piezoelectric energy har-vesting devices to date has focused on the cantile-ver configuration, where the piezoelectric element isdriven transversely in the bending condition (usuallycalled the 31-mode). Also, piezoelectric thick-filmshave been utilised in the cantilever because of theirthinner dimensions compared to bulk components,and much higher piezoelectric properties comparedto thin-films. Traditionally, the thickfilms have been

deposited on a substrate (e.g. silicon, aluminium orstainless steel) then cofired. However, the constrainteffect of the substrate usually leads to poor sinteringand consequently reduced piezoelectric properties.

In this work, a free-standing thick-film cantileverhas been developed and investigated for vibrationenergy harvesting applications to solve the problemcaused by the constraint effect. The issues of opti-mal area covered by electrodes, the effects of proofmass and its position, and the difference of frequen-cy responses between the base excitation and thetip of the cantilever have been explored experimen-tally. Furthermore, in order to address the issue thatthe traditional cantilevered energy harvester couldwork effectively only under limited resonant frequen-cies, an array of free-standing thick-film cantileversas well as a novel magnet-windmill system have be-en designed, fabricated and tested. The former oneobviously widened the working frequency range whi-le the latter one transferred air flow into electricalenergy via utilisation of piezoelectric materials.

Curriculum Vitae: Yang Bai received the BEng degree of Materials Science and Engineeringfrom Tianjin University, China, in 2011. He is now a 2nd year Ph.D. student of the FunctionalMaterials Group, School of Metallurgy and Materials, University of Birmingham, UK. His researchproject focuses on optimisation of piezoelectric composition (lead-based, lead-free) and fabrica-tion\application of free-standing piezoelectric thick-film configuration for energy harvesting.

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S. Bengsch : Wet Chemical Etching of PZT (Lead-Zirconate-Titanate)

Author: S. Bengsch, M.C. Wurz, L. RissingLeibniz Universitat Hannover (Germany)E-Mail: [email protected]: autonomous energy system

Piezo-electric materials are often mentioned inrelation with term of ”‘Energy Harvesting”’. TheseMaterials are producing an electric surface chargewhen a compression load or a tensile load is af-fecting. This attribute of piezo-electric materials ispromising regarding ”‘Energy Harvesting”’. Unfortu-nately the produced voltages and the resulting per-formances are still not highly efficient depending onthe volume. An interesting goal is, to develop an au-tonomous energy system, which is using the piezoelectric technology to harvest the energy from itsenvironment. Concerning this aim the increase ofthe voltages and performances is the major problemwhich has to be solved. Regarding these points thethought about optimizing the already existing sys-

tem ideas was given. This paper deals with the ideaof structuring PZT bulk materials to produce higherefficient piezo-electric harvesting systems using abatch process for micro systems. Therefore the che-mical wet etching process of PZT materials appearsto be promising. Investigations on the behavior ofPZT materials are a main part of this paper. As wellas the ability of structuring the PZT bulk materialwith different types of masks and acid solutions. Thepaper shows differences of the etching results in thecase of isotropic and anisotropic behavior. The out-come points out the possibility of a wet chemicalstructuring of a monolayer PZT bulk material as abase of an Energy Harvesting System.

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S. Bengsch : Analysis of a Precision-Engineered Electro-Magnetic Energy Transformer

Author: S. Bengsch, M.C. Wurz, L. RissingLeibniz Universitat Hannover (Germany)E-Mail: [email protected]: electro-magnetic energy transformer

At a point where resources are getting short,the exploitation of energy from renewable energysources appears to be a main goal in research. Thesearch of alternatives to fossil and nuclear energysources leads to the idea of the term of ”‘EnergyHarvesting”’. This subject deals with the idea of pro-ducing energy out of the environment and can al-ready be found in the field of solar, thermal or windpower plants. The idea with this topic is, to harvestthe energy to supply an autonomous sensor system,for example a data logging system, to achieve in-dependence from external energy sources and toreduce maintenance. Therefore the inductive effectis a big opportunity to produce energy via vibrati-on and to transform mechanical energy into electric

energy to supply a sensor system and to support therecharging of a battery system. In this paper the de-velopment of a demonstrator of an inductive energyharvesting system is carried out. This demonstra-tor is used to identify the challenges and difficultiesfor such a system in the field of micro productiontechnology. The paper will explain the advantages ofdifferent assemblies of inductive energy harvestingsystems as well as solutions to increase the ener-gy output and the resulting performance. In this ca-se a precision engineered electro-magnetic energytransformer was designed, tested and optimized toget to know the opportunities of such a system andthe difficulties which exist between the blueprint andthe results.

Curriculum Vitae:

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Energie Harvesting

J.-J. Choi : (La, Sr)(Ga,Mg)O3− δ Electrolyte-based SOFC by Aerosol Deposition

Author: Jong-Jin Choi, Joon-Hwan Choi, Jungho Ryu, Byung-Dong Hahn, Woon-Ha Yoon,Jong-Woo Kim, and Cheol-Woo Ahn, Dong-Soo ParkKorea Institute of Materials Science (South Korea)E-Mail: [email protected]: solid oxide fuel cell, solid electrolyte, low temperature process

(La,Sr)(Ga,Mg)O3-δ (LSGM) electrolyte basedsolid oxide fuel cells (SOFCs) were aerosol depo-sited on conventionally sintered NiO-GDC anodesubstrates at room temperature to minimize reac-tions between them. Composite cathodes compri-sing (La,Sr)(Co,Fe)O3-δ (LSCF) and polyvinylidenefluoride (PVDF) were similarly deposited at room-temperature. Both electrolytes and cathode maintai-ned good adhesion. Cobalt in the electrolyte redu-ced open cell voltage (∼0.8 vs. ∼1.1 V) probablydue to the decrease of ionic transfer number, andincreased maximum power density (∼0.8 vs. ∼0.5W/cm2 at 650C) by increasing ionic conductivity.

Post-annealing of the electrolyte/anode bi-layer de-creased the open cell voltage due to the interfacialreaction. The peak power density of the cell was in-creased with annealing of 1000C probably due tothe grain growth of electrolyte layer, and decreasedwith annealing at 1200C, representative of tempe-ratures during conventional cell fabrication, due areduction of OCV by severe Ni diffusion and increa-sed electronic conductivity. We have shown that ae-rosol deposition is a promising technique to decre-ase the fabrication temperature and to optimize theperformance of LSGM electrolyte-based SOFCs.

Curriculum Vitae: Jong-Jin Choi is the Senior Researcher of the Korea Institute of MaterialsScience, Changwon, Korea. After being awarded his Ph. D. degree from School of MaterialsScience Engineering in Seoul National University, Korea in 2004, Choi became Post-Doc Re-searcher in Research Institute of Advanced Materials, Seoul National University, Seoul, Korea.Then, he joined the Functional Ceramics Department at Korea Institute of Materials Science in2005. He worked as a visiting scholar School of Materials Science and Engineering in GeorgiaTech, Atlanta, GA, from 2009 to 2010 for the research of surface treatment of catalytic coatingof solid oxide fuel cell(SOFC)?s cathode materials. His research interests are in thick film pro-cess of electro-materials,especially electrolyte \electrode materials of SOFC, oxide electrolyteof lithium ion battery, and various ferroelectrics materials, including sol-gel process, sputteringand aerosol deposition method. He has authored more than 100 papers and 30 patents in theelectro-ceramics process.

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S. Chun-Hua : Arrayed Piezoelectric Unit Design for Harvesting Pavement VibrationEnergy

Author: Sun Chun-Hua, Shang Guang-qing, Li Zhi-rong, Du Jian-hong, Zhang Yong-kangSuzhou Vocational University (China)E-Mail: chh [email protected]: piezoelectric transducers, pavement vibration

The mechanical energy in the pavement causedby the stress of the moving vehicle, can be harves-ted by using piezoelectric transducers. It is reportedthat Innowattech Piezo Electric Generator (IPEGTM)had been installed in a local pavement and put in-to use in conjunction with local electricity grid. It isof great significant to research on energy harvestingfrom pavement.In previous literatures, many kinds of single piezo-electric transducers are discussed without conside-ring the practical use conditions. To harvest ener-gy from pavement vibration on large range, a pie-zoelectric unit in which many transducers are array-ed in series along vertical and horizontal directionsand connected electrically in parallel is designed he-

re. The structural parameters including the diameterand length of PZT, arrayed space, the unit lengthand width and height are optimized in the light ofproperties of potential electrical energy and coup-ling with pavement. Besides, the buried depth underthe pavement is determined. From the analysis re-sult, can a unit of 280*280*10mm with 4mm array-ed space and 30*5mm PZT ceramic chip be obtai-ned. When a unit is buried under the 40mm asphaltpavement, about 0.7MW electric power can be har-vested on each traffic lane and kilometer if the unitefficiency is 40%. This shows that application of thepiezoelectric harvesting technology from pavementvibration has very nice optimistic prospects.

Curriculum Vitae:

86

Energie Harvesting

A. Feldhoff : Thermoelectric Properties of Some Mixed Ionic and Electronic ConductingOxides

Author: Armin Feldhoff, Tobias KlandeLeibniz Universitat Hannover (Germany)E-Mail: [email protected]@pci.uni-hannover.deKeywords: perovskite-type oxides, p-type conductors, Seebeck coefficient, electrical conductivi-ty, power factor

Over recent years, our group has developed newmixed ionic and electronic conducting (MIEC) oxi-de ceramics with the aim to use them as oxygen-transporting membranes in gas separation andpurification at elevated temperature even underharsh conditions [1-4]. Total electronic conductivityis governed by semiconducting electronic transportwhich is provided by polaronic hopping and turns in-to quasi-metallic behavior at high temperature dueto presence of itinerant electrons. These MIEC cera-mic materials exhibit thermoelectric properties byprinciple, which however have not been quantifiedso far. Here, we report on measurements of See-beck coefficient and electrical conductivity which al-low estimate the power factor. Material in focus are,e.g., oxygen deficient Ba0.5Sr0.5Fe0.9Al0.1O3−δ [1]or Ba0.5Sr0.5Fe0.8Cu0.2O3−δ [2]. The findings onmaterials developed initially in other context are dis-cussed to elucidate their applicability for thermo-

electric energy harvesting under high-temperature(high-T) conditions.

[1] J. Martynczuk, F. Liang, M. Arnold, V. Sepelak, A.Feldhoff, Aluminum doped perovskites as high perfor-mance oxygen permeation materials, Chem. Mater. 21(2009) 1586.[2] K. Efimov, T. Halfer, A. Kuhn, P. Heitjans, J. Caro,A. Feldhoff , Novel cobalt-free oxygen-permeableperovskite-type membrane, Chem. Mater. 22 (2010)1540.[3] H. Luo, K. Efimov, H. Jiang, A. Feldhoff, H. Wang, J.Caro, CO2-stable and cobalt-free dual phase membranefor oxygen separation, Angew. Chem. Int. Ed. 50 (2011)759.[4] T. Klande, K. Efimov, S. Cusenza, K.-D. Becker, A.Feldhoff, Effect of doping, microstructure, and CO2 onLa2NiO4-?-based oxygen-transporting materials, J. So-lid State Chem. 184 (2011) 3310.[5] Y. Wei, O. Ravkina, T. Klande, H. Wang, A. Feldhoff, Effect of CO2 and SO2 on oxygen permeation and mi-crostructure of (Pr0.9La0.1)2(Ni0.74Cu0.21Ga0.05)O4+?membranes, J. Membr. Sci. 429 (2013) 147.

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H. Salleh : Design and Implementation of the Wideband Tunable PZT Energy Harvester inPower Generation Plant in Malaysia

Author: Hanim Salleh, Mohd Sofwan Mohd Resali, Mohammed Dhia ShakerUniversiti Tenaga Nasional (Malaysia)E-Mail: [email protected]: energy harvesting, power management

This paper discusses on the design of the wide-band tunable energy harvesting vibration based sys-tem and tested at the Connaught Bridge power sta-tion, Malaysia. The systems are divided into 2 maincomponents which are the energy harvester module(piezoelectric) and the power management and con-ditioning module. In the first component, the ener-gy harvester-generator converted the kinetic ener-gy into electrical energy. A prototype PZT bimorphgenerator was produced and then installed on anelectric motor used to drive the air fan. For the opencircuit, the PZT generators produced at maxiumumof 10.4V AC at different resonant frequencies ran-ged from 47 to 50 Hz. Readings were taken at dif-ferent places on the motor body; it was found thatthe optimal power was produced near the bearingof the motor. This electrical energy is then storedin a super capacitor until sufficient energy is availa-ble to power the sensor, microcontroller and RF mo-dule. The application use AmbioMote24-A (RF, mi-crocontroller and sensor) module from AmbioSys-

tems, as load or targeted electronic application de-vice. This system will use 2 types of sensor whichis acceleration sensor and temperature sensor. TheAmbioMote24-A was programmed with the specialfirmware that turned all sensor and wireless interfa-ces into a low-power state while leaving the energyconversion circuitry operational. The power mana-gement circuit proposes the use of full bridge AC-DC rectifier to convert AC input voltage to usableDC voltage. In order to reduce power consumptionof the circuit and power losses, comparator circuit isimplemented as an adaptive approach to the DC-DCstep-down converter. Simulation results are revea-led that the output voltage from power managementenergy harvesting circuit is 5.0 with output power of1.96mW. The efficiency was found 74%. The totalpower losses were 0.678mW. Lastly this design cir-cuits presents a stand-alone system, single supplyvoltage and compatibility for micro-scale circuit inte-gration.

Curriculum Vitae:

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Energie Harvesting

E. Heffel : Friction Induced Vibrations for Energy Harvesting Applications

Author: Eduard Heffel, Peter HagedornTechnical University of Darmstadt (Germany)E-Mail: [email protected]: vibration-based energy harvesting, self-excited vibrations, friction-induced vibrations

The goal of vibration-based energy harvesting isto power small electronic devices using the kineticenergy from their environment, such as structuralvibrations or motions. The conversion of mechani-cal into electrical energy is basically performed bya piezo element. Such energy harvesting systemscover a wide range of applications, for example self-powered sensors in automobile applications, wire-less sensor nodes for structural health monitoring inaircraft or many other applications in civil or mecha-nical engineering. The major problem of the currentenergy harvesters is their narrow bandwidth. The-re is a significant drop in produced power levels forsmall deviations from the resonance frequency. The-refore, the motivation is to exploit nonlinear tech-niques to increase the overall efficiency of energyharvesting devices, so that they can harvest poweracross varying vibration inputs. One idea is to usea self-excitation mechanism for energy harvestingapplications. The main advantage of these applicati-

ons is that the motion of the excited system is almostindependent of the type or frequency of the excita-tion signal. Here, an important task is to initiate theself-excited vibrations, so that stable limit cycle os-cillations can be generated. This approach promisesto extend the applicability and the overall efficiencyof energy harvesting systems. Such a system canbe realized by a wobbling disk which is in frictionalcontact with a rotor. Due to the rotation of the rotor itcomes to friction-induced vibrations of the wobblingdisk. The generated wobbling motion causes defor-mations of the piezo element, which is mechanicallyconnected to the disk. For a wide range of the ro-tational frequency of the rotor the frequency of thegenerated wobbling motion remains nearly constantand lies, depending on the design of the energy har-vester, in the ultrasonic range. Analytical analysis aswell as experimental investigations will be presen-ted.

Curriculum Vitae: 1985: born July, 23rd in Kamyschin, Russia2005 - 2008: Studies of Mechanical and Process Engineering at Technische Universitat Darm-stadt, Bachelor of Science2008: Adam Opel Award2008 - 2010: Studies of Mechanical and Process Engineering and Mechatronics ? Simulationand Control of Mechatronic Systems at Technische Universitat Darmstadt, Master of Sciencesince Oct. 2010: Research Assistant, Dynamics and Vibrations Group (Prof. Hagedorn), Techni-sche Universitat DarmstadtMay/Jun. 2012:Research visit at the Pontifıcia Universidade Catolica (PUC), Rio de Janeiro, Bra-zilsince Oct. 2012: Member of the Graduate School of Excellence Computational Engineering,Technische Universitat Darmstadt

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S. Hidaka : Pin Structured Substrate Design for Piezoelectric Ceramic Material

Author: Sinichi Hidaka, Daniel Song, Jeong Hun Kim, Jae Won Moon, Hyun Jun Jung, TaeHyun SungHanyang University (South Korea)E-Mail: [email protected]@hanyang.ac.krKeywords: Substrate design, Free body diagram, Bending limitation, FEM(Finite ElementMethod), Piezoelectric energy harvesting

Cantilever piezoelectric energy harvesting systemconsists of piezoelectric ceramic material and me-tal substrate. The role of metal substrate is not onlyaffecting displacement of piezoelectric ceramic ma-terial but it is also for protecting the piezoelectricceramic material from failure. Therefore, designingsubstrate of cantilever beam in the system is veryimportant.It is unavoidable that transferred force is consumedby the substrate of cantilever beam.In this paper, a new type of substrate of cantileverbeam was designed with pin structure to maximizethe output power from the piezoelectric ceramic ma-terial and to prevent the failure.

The pin structure was inserted to the cantilever be-am for additional one degree of freedom. The purpo-se of inserted pin structure was to effectively transferthe force to the piezoelectric ceramic material andprevent force consumption of substrate.Each pin structure has limitation of bending anglein order to prevent the failure of the attached pie-zoelectric ceramic material. By using the simulationprogram, ANSYS, the proposed pin structured de-sign proved the enhancement of power output anddurability of the piezoelectric ceramic material. Thisnew type of pin structured substrate showed possi-ble of higher output power and durability on the fieldof piezoelectric energy harvesting system.

Curriculum Vitae:

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S. K. Hong : Improved Characteristics of Piezoelectric Energy Harvesting System withChange of Total Stiffness

Author: Seong Kwang Hong, Chan Ho Yang, Se Bin Kim, Jae Won Moon, Sinichi Hidaka, TaeHyun SungHanyang University (South Korea)E-Mail: [email protected], [email protected]: Piezoelectric, Energy harvesting, Stiffness, Spring, Cantilever

Piezoelectric energy harvesting system is mainlyused in low-powered circuit and small sensor be-cause of piezoelectric ceramic characteristics of lowoutput power. We contrived a new method to over-come weakness of piezoelectric ceramic which canenhance output power and durability. According toscrew-spring mechanism, piezoelectric cantilevercomprised of piezoelectric ceramic and substratecan be analyzed by modeling on equivalent mecha-nical system including stiffness and mass constant.

On the basis of the equivalent system, experimen-tal set up was designed for complex stiffness. Springis connected to free end of piezoelectric cantileverand floor. Total stiffness was changed by connec-ting springs having different stiffness constant to

the substrate. Result of the experiment was predic-ted by substituting changed complex stiffness to theequivalent system.

Similarly, in experiment, we analyzed trend ofoutput power with increasing complex stiffness byconnecting different types of springs. We found thatoutput power was increasing with increasing com-plex stiffness though analyzed results. Also, dura-bility of piezoelectric device was affected to springbecause of increase of complex stiffness. We perfor-med study on increasing output power and durabilityfor piezoelectric energy harvesting system. This stu-dy on piezoelectric energy harvesting system will beapplied to further research on this field.

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J. Hur : Piezoelectric Properties (1− x)Pb(Zr0.47Ti0.53)O3 − xPb[(Zn0.4Ni0.6)1/3Nb2/3]O3

Ceramics and the Output Power Density of the Energy Harvesters

Author: Joon Hur1, In-Tae Seo2, Sahn Nahm1,2, Chong-Yun Kang1,3, Seok-Jin Yoon3

1 KU-KIST Graduate School of Converging Science and Technology (South Korea)2 Department of Materials Science and Engineering, Korea University (South Korea)3 Principal Research Scientist, Electronic Materials Center, KIST(KIST) (South Korea)E-Mail: [email protected]: Piezoelectric, PZT, Energy harvesting, Power density, Transduction coefficient

(1−x)Pb(Zr0.47Ti0.53)O3−xPb[(Zn0.4Ni0.6)1/3Nb2/3]O3[(1− x)PZT − xP (ZN)N ] ceramics with0.26 = x = 0.31 were sintered at 1100 C, and theirenergy harvesters were fabricated. All specimensexhibit a similar energy convergence efficiency. Ho-wever, the transduction coefficient (d33xg33) incre-ased with x, reaching 21.5x10 − 15m2/N for thex = 0.31specimen; the figure-of-merit of the speci-

mens shows a similar variation. The output energydensity of the energy harvester also increased withx, and a high output energy density of 231mW/cm3

was obtained for the harvester fabricated using thex = 0.31 specimen, indicating that the d33xg33 va-lue significantly affects the output energy density ofthe energy harvester.

Curriculum Vitae: Joon Hur received the B.S. degree from Korea University, Seoul, Korea, in2012, where he is currently working toward the M.S. degree in the department of InformationTechnology-Nanoscience, KU-KIST Graduate School of Converging Science and Technology.His current research interest includes piezoelectric energy harvester.

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S. Ideyama : Piezoelectric Generator Using Impact Induced Vibration

Author: So IdeyamaNihon University (Japan)E-Mail: [email protected]: MEMS, Piezoelectric energy harvesting, Polyimide

In recent years, energy harvesting has been at-tracting attention. The piezoelectric energy harves-ting system has a high energy density characteri-stics and the structure is simple and easy to minia-turize. We have fabricated a MEMS power genera-tion system that generates electricity to collide witha weight in which the piezoelectric element to re-sonate vibration (2Hz about vibration) when a per-son is walking. A piezoelectric generator using theimpact force produces a large output voltage com-pared with other methods using piezoelectric gene-rator. Power generation system consists of a piezo-electric element for the collision and the weight tobe supported by a beam supported at both ends of

the polyimide film. Polyimide used as the beam ma-terial is for high thermal and mechanical, strength.Polyimide beams was set to the natural frequency ofabout 2Hz in length by 10mm, a thickness of 10µm,the weight is put on the weight of 0.1g. Creating athin film of polyimide by using a spin coating, a pro-cessing method is to create a beam supported atboth ends by using the Deep-RIE (Bosch process).The power generation characteristics of the genera-tor is revealed. The experimental results were obtai-ned voltage of 0.086mV. In the experimental results,the highest generating voltage is obtained in the re-sonant frequency.

Curriculum Vitae: 9 September 1989: Born in Chiba in Japan.March 2012: Graduated from College of Science and Technology, Nihon University.Entered Graduate School of Science and Technology for Master course, Nihon University.

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W.-S. Jung : Embossed PZT Thin Film Piezoelectric Energy Harvester

Author: Woo-Suk Jung, Young-Ho Do, Heun-cheul Song, Chong-Yun KangKorea Institute of Science and Technology (South Korea)E-Mail: [email protected]: PDMS, PZT

In this paper, a thin film lead zirconate titanate,Pb(Zr, T i)O3, power generating device is develo-ped, the key point is designed to have an embos-sed structure to increase output power, using poly-styrene spheres. To fabricate the device, PZT, Poly-styrene spheres, Ti/pt, PZT, and pt are stacked onsapphire substrate, layer by layer. The sputtering isused to deposit those materials but used spin coa-ting method for the polystyrene spheres. The firstPZT layer plays a role in a buffer layer that is toprotect the device broken when using a laser lift-offprocess, and Ti/pt is used as an electrode. Since

Ti/pt-PZT-pt layers are deposited on the spheres, itcan have an embossed structure. Then, it is heattreated at 650C to anneal and form the expectedperovskite structure. It transfers from the sapphiresubstrate to PDMS for flexibility by a laser lift-off me-thod. And we represent the output power of the de-vice and comparisons with traditional PZT thin-film.From the experimental results, it demonstrates thatthe embossed structure enables to increase outputpower due to a larger generating surface area andreceiving strain when it is bent.

Curriculum Vitae: Dr.WooSuk Jung is a post doctor in the department of Electric Materials Re-search Center at Korea Institute of Science and Technology. His research interests include stu-dying the growth and assembly of PZT nanostructure for energy harvesting devices, developingcharging electrical circuits for the energy harvesters, and conducting the design and control ofpiezoelectric actuators as well.

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M. Jahn : Energy Harvesting Using Magnetic Shape Memory Alloys

Author: Martin Jahn,, Marcus Neubauer, Jonas Bottcher, Jorg WallaschekLeibniz Universitat Hannover (Germany)E-Mail: [email protected]: magnetic shape memory

The field of energy harvesting has become a pro-mising technique as a power supply for autono-mous electronic devices. Mechanical vibrations arean attractive source, which is typically convertedusing electromagnetic, electrostatic or piezoelectriceffects. The use of magnetic shape memory alloys isa very novel technique. They have the ability to con-vert mechanical energy into magnetic energy andvice versa. Compared to other transducer, they offera large strain of about 10%.

In this publication, a generalized model of ma-gnetic shape memory alloys is developed, which isused for designing the energy harvesting system.The nonlinear dependencies between the mecha-nical deformations as the system input and the dis-sipated energy at the load, which is modelled as alinear resistance, are derived in detail.

As a result of this generalized model, the systemparameters like the electrical resistance can be op-timized, and the output power estimated.

Curriculum Vitae: Dr.-Ing. Marcus Neubauer studied mechanical engineering at the Leibniz Uni-versity Hannover. In 2003 he finished his studies with a Diploma thesis about friction inducedvibrations in disc brakes of high speed trains. Since then, he works at the Institute of Dyna-mics and Vibration Research (IDS), Hannover. 2008 he received his Doctor degree for a workabout vibration damping using shunted piezoceramics. He currently works as a Senior ResearchDirector at the Adaptronic Systems Group at the IDS. His research interests include friction in-duced vibrations, semi-active tuned mass damper, piezoelectric shunt damping, shape memoryalloys, energy harvesting and machine dynamics. During his career, he published more than 20reviewed journal papers and received Dr. Jurgen Ulderup prices for outstanding achievements inintermediate diploma (2000) and diploma (2003) and the PE Publishing Prize of the Journal ofAutomobile Engineering in 2008.

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C. Jianyu : An Explicit Multi-Grid Algorithm to the Air Intake Annulus of the AirflowResonant Piezoelectric Generator

Author: Cai Jianyu1, Chen Hejuan2

1 Nanjing University of Science and Technology (China) 2 Nanjing College of Chemical Techno-logy (China)E-Mail: [email protected]: explicit multi-grid algorithm, airflow resonant piezoelectric generator, turbulencemodel , Navier-Stokers equation, pipe wall pressure,

An explicit multi-grid algorithm was used to analy-sis the flow pattern in air intake annulus, with a varia-ble cross-section, of airflow resonant piezoelectricgenerator. Using the K-e turbulence model, by sol-ving the three-dimensional incompressible Navier-Stokers equation, coarse grid and fine grid modelswere calculated by MUSCL and TVD formats. Re-

sults show that the MUSCL format of the unrestric-ted function has a better resolution for the ring gapvariable cross-section air intake structure, compa-ring to the TVD format. A clearer stream spectrumcan be obtained with the explicit multi-grid algorithm.Additionally, distribution curve of the pipe wall pres-sure shows good agreement with the real.

Curriculum Vitae:

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H. J. Jung : Study on Increasing Current for Hitting Type of Piezoelectric EnergyHarvesting System

Author: Hyun Jun Jung, Jae Won Moon, Sinichi Hidaka, Chan Ho Yang, Daniel Song, Tae HyunSungHanyang University (South Korea)E-Mail: [email protected]@hanyang.ac.krKeywords: Piezoelectric, Current, Hitting, Vibration velocity, Energy harvesting

When piezoelectric energy harvesting system ge-nerates voltage, it is proportional to the stain ofpiezoelectric material. Thus, many researches havebeen studied on generating higher voltage for higheroutput power. When piezoelectric material is appliedto higher stain for higher output voltage, it is easyto be destroyed because piezoelectric material hasbrittle characteristics. Thus, method on generatinghigher output power with higher voltage has limitati-on.

In nature of piezoelectricity, when the vibration ve-locity of piezoelectric material is maximum, currentis maximum. In this paper, we investigated the re-lationship between vibration velocity and current ofpiezoelectric material. We also studied about redu-

cing the strain for enhanced durability of piezoelec-tric material and increasing the current for higheroutput power in the hitting type piezoelectric energyharvesting system.

In order to investigate the relationship between vi-bration velocity and current, and to increase the cur-rent, we designed mechanical system which trans-mits higher force at the position of maximum vibrati-on velocity. Also, we set up the stick at the bottom ofcantilever to reduce the strain than existing hitting ty-pe piezoelectric system. In the experimental results,we found the optimizing condition which could incre-ase the current and durability of piezoelectric mate-rial.

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H.-W. Kang : Piezoelectric Energy Harvester Using Shear Mode

Author: Hyung-Won Kang1,2, Seung-Ho Han1, Chan-Sei Yoo1, Hyeung-Gyu Lee1, Jung-WookPark21 Korea Electronics Technology Institute (South Korea)2 Yonsei University (South Korea)E-Mail: [email protected]: Energy harvester, shear mode

Due to the worldwide depletion of conventionalfossil energy, research for alternative energy hasbeen active. Research on piezoelectric energy har-vest that converts vibration energy into electricalenergy is also increasing.

In this study, we propose piezoelectric energy har-vester using shear mode. Energy harvester was fa-bricated using two piezoelectric bodies (24 x 6 x0.6 [mm3]) based on the specification of shear mo-de. Powers generated from energy harvester provi-de possibility of energy source to be used.

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M.-G. Kang : Oxide Semiconductors Embedded on Polymer Films for FlexiblePiezoelectric Energy Harvesting System

Author: Min-Gyu Kang1,2, Young-Ho Do1, Woo-Sung Choi1, Hyun-Cheol Song1, Woo-SukJeong1, Sahn Nahm2, Seok-Jin Yoon1, Chong-Yun Kang1,2

1 Korea Institute of Science and Technology (South Korea)2 Korea University 145 (South Korea)E-Mail: [email protected]: oxide semiconductors, rectifier, excimer laser annealing, piezoelectric energy har-vesting

Piezoelectric energy harvesting system in orderto obtain electricity from environmental vibrationsources has contained piezoelectric energy harves-ters for electrical power generation, active devicesfor rectifying the output power as AC-DC converter,and capacitors for DC-DC converter. In this works,we demonstrate active devices as rectifiers on flexi-ble polymer films for the piezoelectric energy har-vesting system. ZnO based oxide thin films weredeposited on the polymer films at room tempera-ture. For the heat treatment, we used excimer la-ser annealing (ELA) technique which is an attracti-ve method for the low-temperature heat treatmentof the thin films, that led improvement and control of

a carrier concentration and mobility of the ZnO ba-sed oxide thin film. To determine the optimum con-dition of the ELA, we simulated heat transfer phe-nomenon in each material with the ELA modelingusing COMSOL multi-physics simulation program.The electrical performance of the rectifiers contai-ned diodes were analyzed using electrometer andimpedance analyzer. Consequently, we obtained theflexible active devices for energy harvesting systemthat is embedded on the polymer films by ELA tech-nique. Furthermore, the energy harvesting systemcould directly converse to usable electrical energyfrom vibration sources.

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C. V. Karadag : A Piezoelectric Cantilever Beam with Tunable Natural Frequency

Author: Cevat V. Karadag, Nezih TopalogluYeditepe University (Turkey)E-Mail: [email protected]: piezoelectric energy harvesting, tunable natural frequency, cantilever beam, piezo-motor

In a cantilever beam piezoelectric energy harves-ter, operation in resonance yields significant amountof electrical power generation, whereas the gene-rated power significantly drops when the ambientvibration frequency is out of resonance. Auto-tuningof the natural frequency of the cantilever beamsmoothly and efficiently can be an effective solu-tion to this problem.

In this paper, it is proposed to tune the natu-ral frequency by sliding the tip mass of the energyharvesting cantilever beam, with the help of a line-ar actuator (Figure 1). As for the actuator, a linearpiezomotor. The selected piezomotor brand, piezo-wave R©motor, is very miniature: it has a longestdimension of 14 mm. In addition, its shaft has toovercome static friction to move when the motor ispowered; which makes the motor self-locking. Thepower consumption of the motor during activity can

easily be predicted because the power consumptionrate is mostly constant over time.

Tuning the position of the tip mass is made by con-trolling the piezomotor with microcontroller. At theinitial step, the output voltage is recorded and thetip mass is moved in positive direction by a smallamount. The output voltage is again recorded andcompared with its previous value. Depending on thesign of the change in output voltage, the tip mass isagain moved in positive or negative direction. Thisroutine is repeated until the change in output volta-ge is below a threshold value. It was shown that theposition of the tip mass can be auto-tuned, so thatthe system is kept in resonance. However, the mo-tor and the controller is currently powered externally.The future work is to build a cantilever beam pie-zoelectric energy harvester with self-sufficient auto-tuning.

Curriculum Vitae: Dr. Nezih Topaloglu received his Bachelor’s degree in Electrical & ElectronicsEngineering from Bogazici University, Turkey and his Ph.D. degree in Mechanical & MechatronicsEngineering from University of Waterloo, Canada. He is currently a faculty member in the Depart-ment of Mechanical Engineering at Yeditepe University, Turkey. His research includes vibrationenergy harvesting, smart structures, microsystems modeling and electrothermal microactuators.

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J. H. Kim : Effect on Hitting-Typed Piezoelectric Energy Harvesting System with the Areaof Hit Piezoelectric Device

Author: Jeong Hun Kim, Min Sik Woo, Ki Hwan Baek, Seong Kwang Hong, Shinichi Hidaka,Tae Hyun SungHanyang University (South Korea)E-Mail: [email protected], [email protected]: Piezoelectric, Energy harvesting, Hitting area, damage, generation

A specific point of substrate attached to piezo-electric ceramic was hit by hitting stick in existinghitting-type piezoelectric energy harvesting.For the existing hitting-type system, the pressure perunit area is high and the force is concentrated on thesubstrate due to small hitting area of the substrate.As a result, there is a problem that substrate in theattached piezoelectric material is easily damaged.In this paper, hitting type piezoelectric energy har-vesting system is improved against the damage ofthe piezoelectric material. And experiments werecarried out for effectively transfer power to impro-ve output power generation. As the area of hitting

points increases, the power pressure per unit areadecreases with evenly distributed stress. Based onthis theory, the hitting point’s area was changed andin each area of piezoelectric power generation wasmeasured.In addition, in order to verify this pheno-menon, the simulation of the stress distribution fol-lowing the changed area was shown. As a result,pressure per unit area on the substrate can be de-creased as the hitting area on the substrate incre-ases. And the stress was evenly distributed, so theforce was delivered to the piezoelectric materials ef-fectively, and the higher power generated.

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S. B. Kim : Study of Optimizing Acceleration Distribution on Time-Varying with EqualInput Energy in Piezoelectric Energy Harvesting

Author: Se Bin Kim, Hyun Jun Jung, Daniel Song, Chan Ho Yang, Seong Kwang Hong, TaeHyun SungHanyang University (South Korea)E-Mail: [email protected]@hanyang.ac.krKeywords: Piezoelectric, Energy harvesting, Acceleration distribution, Efficiency, Time-varying

Many researches are underway by cantileverstructure using piezoelectric module. In this struc-ture, all the movements of piezoelectric elementdepend on applied force, which also can be consi-dered as acceleration. The focus of these previousresearches is how to obtain higher acceleration anddeformation in the piezoelectric element at any gi-ven time.

However, in every system, the total energy ofinput source is fixed at any given time. Also, the ef-ficiency of piezoelectric harvesting is low comparedto that of other generators. Therefore, the key pointfor piezoelectric harvesting is the high-efficiency.

Energy is consisted of integrated force for timethat is proportional to the acceleration. Thus, when

the fixed energy applies to piezoelectric element,the essential point is distribution of acceleration fortime-varying and it is important to find optimizationof that for the high-efficiency.

In order to measure the accurate input energy,we use the exciter. In this experiment, input energyis the driving power of exciter and output energy isthe output power of piezoelectric element. Also, weuse a bearing to transmit the vibration of exciter topiezoelectric element for minimum loss.

Through this study, the optimized distribution ofacceleration is found with the same input energy.This result helps to make easy to obtain the high-efficiency in the all filed, and to curtail the time toachieve the high-efficiency.

Curriculum Vitae:

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C. Kim : Optimum Design of Cantilevered Energy Harvesters with Piezoelectric Materialsand Vortex Shedding

Author: Cheol Kim, Seongmin Yun, Yonghwan KwonKyungpook National Univesity (South Korea)E-Mail: [email protected]: Energy Harvester, Piezoelectric Material, Vortex, Optimization, Cantilever

A cantilevered piezoelectric energy harvesterwhich vibrates in the region of vortex shedding wasdesigned and analyzed electro-mechanically. CFDanalysis was performed to obtain vortex sheddingfrequency around various shapes of bodies placedin an air stream. In order to maximize electric power,the exciting frequency of the cantilevered energy de-vice was tuned as close to the natural frequency ofthe beam as possible. An efficient analysis methodfor cantilevered beam-type piezoelectric energy har-vesters was also developed for the prediction of theelectric power output, based on the finite elementmethod and the design optimization of piezoelec-tric materials. The optimum topology of a piezoelec-tric material layer could be obtained by a newly de-veloped topology optimization technique for piezo-electric materials which utilized the electromecha-nical coupling equations, MMA (method of movingasymptotes), and SIMP (solid isotropic material with

penalization) interpolation. Using the design optimi-zation tool, several cantilevered beam-type piezo-electric energy harvesters which fluctuated in theregion of vortex shedding were developed, that con-sisted of two different material layers - piezoelectricand high carbon steel layers. Using the method, theeffects of geometric parameters and several piezo-electric materials (PZT, PVDF, and PZT fiber com-posites) attached to the beam device on power ge-neration were investigated and the electric charac-teristics were evaluated. The three kinds of mate-rial coefficients such as elasticity, capacitance, andpiezoelectric coupling are interpolated by elementdensity variables. Then, the shape and size designoptimizations for the cantilevered beam geometrieswith an optimum piezoelectric topology have beenperformed for a base model. Analysis was validatedby experiments.

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M. Kroener : A Multi-Source, Microcontroller Based Energy Management System Withoff-the-shelf Components

Author: Michael Kroener, Radhika Prabhakar, Peter WoiasUniversity of Freiburg (Germany)E-Mail: [email protected]: Energy Management System, Multiple Sources, Successive Charging

A versatile energy management system with lowpower consumption and a defined cold-start behavi-or when energy is only sparsely available [1] is veryimportant to enable stable functioning of wirelessautonomous systems. In applications where simul-taneous harvesting from different sources, such asvibrations, photovoltaics or thermoelectrics is inten-ded, the demands rise even further according to thedifferent input characteristics of these generators.

We present a versatile energy management sys-tem designed on the basic prerequisites of a hybridpiezoelectric (high voltage, low current) and electro-dynamic (low voltage, high current) micro-energy-harvester. The system is designed such that it notonly uses two input sources, but also two differentstorage mechanisms: a long-term storage systembased on a 0.7 mAh, 4.0 V nominal voltage Thiner-gy thin-film battery and a mid-term energy storagesystem based on a 1 F Illinois EDLC super capacitorcapable of delivering output currents as high as 3A. Prior to setup, different types of super capacitors

(EDLC, PAS) were investigated for their long-termcharge retention capabilities with respect to char-ging times, as well as subsequent charging cycles.Both showed decreasing self-discharge effectiven-ess with successive charging.

An 8-Bit ST Microelectronics STM8L152C626 mi-crocontroller was used, which has a deep sleeppower consumption of only 0.35 µA at a 2 V supplyvoltage. Based on periodic voltage measurementsof both storage capacitors, the microcontroller de-cides which power supply to use. If the battery islow, it can be charged from the capacitor with volta-ges from 0.9 V with an integrated TI61220 step-upconverter (Texas Instruments), which also impliesthat the startup voltage has the same value. For de-monstration purposes, an RF transmitter is integra-ted in order to transmit the current system state to abase station, and a shutdown message is sent if allstorage devices are empty.

[1] M. Wischke, M. Masur, M. Kroner & P. Woias, Vibra-tion harvesting in traffic tunnels to power wireless sensornodes, Smart Materials & Structures, 2011, 20, 085014

Curriculum Vitae: Dr. Michael Kroner studied Engineering Physics at Munster University of Ap-plied Sciences. He wrote his diploma thesis at the Fraunhofer Institute for Silicon Technologies(ISiT) in 2004. Since then he worked at the Department of Microsystems Engineering (IMTEK) inFreiburg on his doctorate thesis about biplanar micro ion traps, graduating in 2010. Currently heworks as a group leader at the ”Laboratory for Design of Microsystems” on the topic ”Micro Ener-gy Harvesting”, with a research focus on thermomechanical, piezoelectric, and thermoelectricgenerators and materials.

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K. Kumar : CHEW: A Compact Harvesting - Energy Windbelt

Author: Krishna Kumar, Shamanth Kumar, Ranjith J N, IIT Madras,Prabhakar T V, Soumya NS, Madhuri Sheethala Iyer, Jamadagni H SDESE, Indian Institute of Science (India)E-Mail: [email protected]: Energy harvesting, Wind Belt, Super-Capacitors.

We developed a novel and cost effective methodfor wind energy harvesting. The model harvestswind energy generated from ceiling fans and ACblowers. We use the Aeroelastic flutter principle toconvert wind energy to vibration. Vibration is thenconverted to electrical energy using Electromagne-tic induction. Our model is compact for home app-lications. Its dimensions are 7in X 2.1in X 2.75in. Itcan be easily fixed to AC vents and fans. Our mo-del has dual energy trapping units with 2 pairs ofmagnets placed on either side of a belt, which iswound around bobbins. A tension adjusting screw isalso part of the design. The belt is 6 inches in lengthand can carry magnets of different sizes; based on

the application requirement. For example, in indoorapplications such as a table fan, we have used ma-gnets of 6mm diameter with a belt of width 7mm. Forlower wind speeds such as an AC vent, we used abelt of 6mm width and magnets of 5mm diameter.For the outside environment where wind speeds arenot consistent, we used magnets of 4mm diameterand a belt of 5mm width. These sizes were found tobe optimal to harvest energy from flutter. This artic-le provides a step-by-step procedure for constructi-on and working of the compact wind energy harves-ter. Our article has harvested power measurementresults for energy reuse from several domestic app-liances.

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J.-T. Lin : Low Frequency Energy Harvesting From Coupled Rolling Magnet Spheres

Author: Ji-Tzuoh Lin1,2, Kevin Walsh2, Bruce Alphenaar21 Ambiharv Inc. (United States) 2 University of Louisville (United States)E-Mail: [email protected]: Low Frequency, Energy Harvesting, Rolling Magnet Sphere, Attractive Coupling

In this presentation, low frequency vibration ener-gy harvesting is realized by coupling a magnet sphe-res on a PZT cantilever with an attractive force. Theattractive force between a permanent magnet anda couple of magnet spheres not only form a staticbond but also evolve into a dynamic bond upon exci-tation. The magnet spheres roll back and forth, dueto the attractive force when its inertia frame oscilla-tes, on a minimally frictional PZT surface of a canti-lever beam. The rolling motion of the magnet sphe-res change their position on the cantilever and pro-vide changing torque on the PZT cantilever to pro-duce charges.The resonant frequency, normally determined by thestiffness and the proof mass fixed at the moving endof the cantilever, should be considered here moreon a dynamic term. Especially, the proof mass isno longer static. In other words, the attractive for-

ce between the two magnets and the mass of themagnet spheres constitute the proof mass, which isalso a function of acceleration. It matters becausethe magnitude of the acceleration changes the di-stance between the two magnets, and the positionswhere the proof mass sits on the cantilever.Moreover, the spheres can move and roll in the lon-gitudinal (y) direction in responses to both the x-axisand z-axis excitation directions. Each excitation di-rection, however, presents distinct bending motionson the cantilever. In the z-axis excitation direction,the cantilever moves up and down across z=0, si-milar to that of motion with a fixed proof mass. Onthe other hand, in the x-axis excitation direction, thePZT cantilever oscillates mostly below z=0 position,a pure rolling pressure from the magnet spheres.Detailed experiment results and calculations of theresonant frequency will be presented.

Curriculum Vitae: Dr. Ji-Tzuoh Lin earned his Bachelor and Master degrees both in physics. Heobtained a Ph.D. in Electrical Engineering from University of Louisville in which his work was ondeveloping ultra-high sensitive strain sensors and their inductively coupled telemetry systems. Heextended his research enthusiasm in energy harvesting for wireless sensors as a research scien-tist at the University of Louisville and Ambiharv Inc. Over the years, he has developed non-linear,efficient vibration dynamics for broader spectrum energy harvesting and designs on extremelylow background noise switch relays and sensor systems.

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W. Q. Liu : Optimization of a Bistable Piezoelectric Harvester for Wideband VibrationEnergy Harvesting

Author: W.Q. Liu, F. Formosa, A. Badel, Y. Wu, Amen E. AgbossouUniversite de Savoie (France)E-Mail: [email protected]: Bistable, Energy harvesting, Piezoelectric, Optimization

Bistable vibration energy harvesters (BVEH) areattracting more and more interests because of theircapability of increasing the operating bandwidthcompared to the classical linear oscillator approach[1-2]. This paper presents the optimization of a novelBVEH based on a lumped spring mass system in abuckled configuration as shown in figure 1. It is com-posed of two piezoelectric transducers, four flexiblehinges and an inertial mass. Compared to the mo-re classical bistable harvesters which used magnetsor buckling beams [2-5], it presents a better powerdensity and potential for optimization. A theoreticalmodel has been developed and shows good agree-ment with experimental results. The complex non-linear behavior is fairly captured as shown in figure2 which is obtained from a realized bistable harves-ter subjected to different chirp excitations. Based onthis model the optimization of the BVEH is perfor-med. The model shows that the power normalizedby mass Pn = P/M for a determined excitation isonly related to 4 parameters:

• the characteristic frequency f0 (natural reso-nant frequency for small excitation)

• the electromechanical coupling coefficient k2

(as defined in [6])

• the mechanical damping ξ

• the buckling level ε = x0/L

Considering that k2 and ξ are usually fixed for aselected piezoelectric component, the optimization

is focused on f0 and ε. Using forward and rever-se chirp excitations between 40-120Hz for 1 and 2gamplitudes, the normalized power is shown in figu-res 3 and 4. The result of the linear vibration energyharvester (LVEH) featuring the same parameters isalso plotted for comparison. It is found that whenf0 and ε are small enough to ensure the inter-wellmotion (jumps between the two stable positions) tohappen, the scavenged power of BVEH is higherthan for an equivalent LVEH as shown in figure 3(the lower left corner). Whenever the inter-well moti-on does not happen, the BVEH and LVEH harvestedpower are comparable. As the chirp excitation is in-creased to 2g, the favorable inter-well area is enlar-ged as shown in figure 4. The existence of optimalparameters for the BVEH has been demonstratedfor the ideal case of chirp excitations. Based on the-se results, the future works will aim at the realizationof the optimal device. Because real environment ex-citations are different from the chirp case, the devicewill be tested in various environments and the re-sults compared with the linear approach. Moreover,the energy extraction strategy is another optimizati-on route for optimization and will be considered. [1]L. Gammaitoni et al 2009 Applied Physics Letters 94(16)164102.[2] S. C. Stanton et al 2010 Physica D 239(10) 640-653.[3] R. Masana et al 2011 Journal of Sound and Vibration330(24) 6036-6052.[4] F. Cottone et al 2009 Physical Review Letters 102(8)080601.[5] M. Ferrari et al 2010 Sensors and Actuators A: Physi-cal 162(2) 425-31.[6] A. Badel et al 2005 Journal of Intelligent MaterialsSystems and Structures 16 889-901.

Curriculum Vitae: Weiqun Liu received the master degree in mechatronic engineering from University of Scienceand Technology of China, Hefei, China, in 2008. He is currently pursuing the Ph.D. degree at the Laboratory ofSystems and Materials for Mechatronics, in the University of Savoie, Annecy, France. His research interests includeelectromechanical systems and especially micro-power generators.

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J. W. Moon : Multi Piezoelectric Array Energy Harvesting System for Watt Level Power

Author: Jae Won Moon, Hyun Jun Jung, Se Bin Kim, Ki Hwan Baek, Sinich Hidaka, Jeong HunKim, Tae Hyun SungHanyang University (South Korea)E-Mail: [email protected]@hanyang.ac.krKeywords: Piezoelectric, Energy harvesting, Multi piezoelectric array, Hitting, Impedance mat-ching

In recent years, many piezoelectric energy har-vesting studies have been researching. However,output powers of these studies have scales from on-ly micro-watt to milli-watt. The milli-watt scale is un-suitable for various power sources, so we must im-prove output power of piezoelectric energy harves-ting system for practical use.For enhanced output power, this paper investigatedmulti piezoelectric array energy harvesting systemwhich can overcome output power limitation of asingle piezoelectric energy harvesting system. Theenergy harvesting system of this study was app-lied with hitting type method for the multi piezoelec-tric array energy harvesting system, because out-put power of hitting type is higher than output powerof vibration type in piezoelectric energy harvesting

system.We investigated the effect of various conditions onthe output power such as rectifier and piezoelec-tric module configuration, impedance matching andhpm (hit per minute) for piezoelectric energy harves-ting system that consisted of 4 - piezoelectric modu-les. And we established the optimized conditions formulti piezoelectric array energy harvesting systemby using a designed test model.Based on the optimized conditions, we designed themulti piezoelectric array energy harvesting systemthat consisted of 102 - piezoelectric modules withdimension of 35 mm × 45 mm × 0.2 mm repective-ly. Finally, we were able to obtain the output powerof 1.99 W.

Curriculum Vitae: Education:B.S., Electrical Control Engineering, Hanyang University, 2010

Research Interests:Piezoelectric energy harvesting system, Energy storage circuit analysis

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L. Mateu : Maximizing the Output Power of a Piezoelectric Generator from the AdmittanceMeasurement by selecting the Rectification Technique

Author: Loreto Mateu,Fraunhofer Institute for Integrated Circuits IIS (Germany)E-Mail: [email protected]: energy harvesting, rectifiers, piezoelectric transducers

AC-DC converters that perform the rectificationof the power harvested by piezoelectric transducersare divided in two different groups: non-linear andlinear. A diode bridge is considered a linear rectifierwhile a non-linear technique implies the inversion ofthe piezoelectric voltage through an inductor whenthe maximum displacement of the piezoelectric ele-ment is reached.

It is possible to predict which one of the two tech-niques will provide the maximum output power fora certain piezoelectric transducer. If a piezoelectrictransducer is weakly coupled, k2Qm ≤ 2or k

2

ζm 1,

a non-linear technique will harvest more power;where k2 is the electromechanical coupling coef-ficient, Qm is the mechanical quality factor and ζmis the modal damping ratio of the mechanical sys-tem (Guyomar, Sebald, Pruvost, Lallart, Khodaya-ri, & Richard, 2009) (Lien, Shu, Wu, Shiu, & Lin,2010). However, this methodology implies that thepiezoelectric constants as well as the mechanicalstructure parameters of the piezoelectric transducerare known.

Measurements of the admittance of different pie-zoelectric transducers have been done with an AU-

TOLAB PGSTAT302N potentiostat/galvanostat. Thefigures of merit k2Qm and k2

ζmcan be deduced from

the admittance circle of the piezoelectric transducersince (Ikeda, 1990):

M =|Ym0||Yd|

=1R

ω0Cd= QmK (0.1)

where factor K is proportional to k2. The ratio of thereal to the imaginary part of the piezoelectric ad-mittance is an equivalent figure of merit to the onespresented before. Furthermore, the measurement ofthe admittance circle allows to calculate the ratio ofthe maximum power harvested with a resistive load,analogous to a linear technique, to the maximumpower harvested with a complex load, comparableto a non-linear technique (Brufau-Penella & Puig-Vidal, 2009), see Figures 1 to 4.

Powerratio =Pnon−complPcompl

(0.2)

This paper presents a method to quantitativelyestimate which rectification technique harvests mo-re power for each piezoelectric transducer, by mea-suring the admittance of the piezoelectric transdu-cer.

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S. Ravi : Numerical Modelling of Piezoelectric Energy Harvesting Devices Driven by FlowInduced Vibrations

Author: S. Ravi, A. ZilianUniversity of Luxembourg (Luxembourg)

E-Mail: [email protected]: Transfer matrix, piezoelectric design study

Piezoelectric materials have the ability to convertmechanical vibrations into electrical energy and vi-ce versa by virtue of its crystalline structure. Thisresearch mainly investigates piezoelectric structuralvibrations due to the action of fluid forces when thepiezoelectric structure is placed in a fluid flow. Toharvest energy from such vibrations the kinetic ener-gy of the fluid is first transformed into cyclic strainingenergy of the piezoelectric material, which is thendissipated or stored in a harvesting circuit with sui-table electrical components. The harvesting circuitis connected to the electrodes placed on the piezo-electric patches. This results in a strongly coupledsystem where there is boundary-coupled fluid struc-ture interaction, volume-coupled piezoelectric me-chanics and the coupling between the structure andthe electrical circuit. The experimental layout of sucha harvesting device placed in a fluid-flow is givenin [1]. This paper introduces a monolithic approachthat provides simultaneous solution to the stronglycoupled system, which also inherently accounts forthe backward coupling between the harvesting cir-cuit and the structure. The governing partial dif-ferential equations are formulated in integral formby weighted residuals method. The resulting weakform is discretized in a space-time finite element fra-mework [2, 3] based on mixed velocity-stress/rate

of potential-dielectric displacement setting. This fra-mework provides a holistic approach that simulta-neously solves the coupled equations in a singlealgebraic system. This mixed finite element formu-lation is used for the discretization of the solid do-main where four independent fields are used viz.,velocity, mechanical stress, rate of electric potentialand dielectric displacement. The fluid is describedby the incompressible Navier-Stokes equations [4].The numerical results will be compared to simplecases with closed form solutions available from lite-rature. [1] G.W. Taylor et al., ”‘The Energy HarvestingEel: a small subsurface ocean/river power generator”’,IEEE J. of Oceanic Engng, Vol. 26, pp. 539-547, (2001).[2] Zilian, A., Legay, A.. ”‘The enriched space-time finiteelement method (EST) for simultaneous solution of fluid-structure interaction”’. International Journal of NumericalMethods in Engineering. Vol. 74, pp. 305-334, (2008). [3]Zilian, A., Dinkler, D. And vehre, A.. ”‘Projection basedreduction of fluid structure interaction systems using mo-nolithic space-time modes.”’ Computer Methods in Ap-plied Mechanics and Engineering. Vol. 198(47-48), pp.3795-3805, (2009). [4] P. Sun, D. Dinkler, and A. Zilian,”‘Simulation der aktiven Schwingungskontrolle von Fluid-Struktur-Wechselwirkung durch piezoelektrische Mate-rialien”’, PAMM, 8: pp. 10519-10520,(2008).

Curriculum Vitae: 2/2011 - 6/2012: Master of Science in Computational Mechanics, Ecole Cen-trale de Nantes, France9/2010 - 1/2011: Master of Science in Computational Mechanics, Swansea University, UK.Master Thesis: Dynamic simulations of flow around a full-size rowing blade under real conditi-ons: Validation of ISIS-CFD solver by comparison with experimental data.01/02/2013 - Present: PhD Student at Faculty of Science, Technology and communication, Uni-versity of Luxembourg

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B. Ren : Investigation of Piezoelectric Energy Harvesters Based on Relaxor-Based SingleCrystals

Author: Bo Ren, Haosu Luo, Chundong Xu, Zhu Liang, Xiangyong Zhao, Wenning Di,Chinese Academy of Sciences (China)E-Mail: [email protected]: energy harvesting, CANDLE, piezoelectric, PMNT single crystal

During the past decade, piezoelectric energy har-vesting from mechanical vibrations of ambient envi-ronments has been a hot research topic due to itspotential application in many fields and advantageof simple device structure compared to other me-thods such as using electromagnetic and electrosta-tic effects. In recent years, relaxor piezoelectric sin-gle crystals such as (1 − x)Pb(Mg1/3Nb2/3)O3 −xPbT iO3 (PMN-xPT or PMN-PT) have attractedcontinuous attention due to the well-known ultra-high electromechanical response. The piezoelec-tric strain constants d33, d31 and electromechani-cal coupling coefficients k33, k31 could reach ashigh as 2500 pC/N, -2500 pC/N and 0.94, 0.95,respectively. In our work, we present a high per-formance piezoelectric energy harvester CANtileverDriving Low frequency Energy harvester (CAND-LE) consisting of cantilever beam and cymbal

transducers based on piezoelectric single crystal0.71Pb(Mg1/3Nb2/3)O3 − 0.29PbT iO3. Electricalproperties of CANDLE under different proof mas-ses, excitation frequencies, and load resistancesare studied systematically. Under an acceleration of3.2g (g=9.8 m/s2), a peak voltage of 38 V, a maxi-mum power of 3.7 mW were measured at 102 Hzwith a proof mass of 4.2 g. Combined with variouslow power-consumed sensors, the energy harves-ters could be used as the passive sensors to monitorthe movement of vehicle, the fatigue of aircraft andbridge, and the safety in the mine and volcano. Theywill play important role in the high technical fields ofenvironment, energy, traffic and healthcare etc., tobe used for developing green energy, reducing car-bon emission, and establishing environment-friendlysociety.

Curriculum Vitae: Bo Ren was born in Huaibei, China in 1985, and received his B.S. degreein materials of science and engineering from University of Science and Technology of China(USTC), Hefei, China, in 2006, and D.E. degree in materials science from Shanghai Instituteof Ceramics, Chinese Academy of Sciences (SICCAS), Shanghai, China, in 2011. During Nov.2008 - May. 2009, he worked as a Research Assistant in the Hong Kong Polytechnic University.His current position is Assistant Professor in SICCAS and his research interests are ferroelectricrelaxor single crystals and their applications in piezoelectric energy harvesting devices.

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J. Ryu : Magnetoelectric Benders with Piezoelectric Single Crystal and MagnetostrictiveMetal for Energy Harvesting from Mechanical Vibration and Electromagnetic Wave

Author: Jungho Ryu1, Rahul C. Kambale1, Dong-Soo Park1, Woon-Ha Yoon1, Jong-Jin Choi1

Jong-Woo Kim1, Cheol-Woo Ahn1, Byung-Dong Hahn1, Dae-Yong Jeong2

1 Korea Institute of Materials Science (South Korea)2 Inha University (South Korea)E-Mail: [email protected]: piezoelectric single crystal, Magnetoelectric, energy harvesting

The magnetoelectric (ME) rectangular uni-morph structure of piezoelectric Pb(Mg1/3Nb2/3)O3-Pb(Zr,Ti)O3 single crystal cantilever beam on ma-gnetostrictive Ni substrate was designed with<001> and <011>- cut crystallographic directionsand investigated their ME response and vibrationbased energy harvesting behavior. Both magneto-electric voltage coefficient (αME) and mechanicallyharvested power output was found to be depen-dent on the crystallographic cut directions of PMN-

PZT. The maximum αME and power output of 7.28V/cm·Oe and 1.63 mW was observed for <011>PMN-PZT/ Ni unimorph ME structure under reso-nance drive action. The <011> PMN-PZT singlecrystal showed strong in-plane anisotropic behavior(d31 and d32) and its effect on the magnitude of αMEand harvested power output. The effects of the ma-terials properties on the ME and energy harvestingperformance are discussed to provide some usefulfacts to design of ME energy harvesting devices.

Curriculum Vitae:

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R. Salloum : Tuning of a Vibration Absorber with Shunted Piezoelectric Transducers

Author: Rogerio Salloum, Oliver Heuss, Dirk MayerFraunhofer Institute for Structural Durability and System Reliability LBF (Germany)E-Mail: [email protected]: shunt damping, tuned mass absorber, active vibration control, semi-active, frequencytuning

In order to reduce structural vibrations in nar-row frequency bands, tuned mass absorbers can bean appropriate measure. A quite similar approachwhich makes use of applied piezoelectric elements,instead of additional oscillating masses, are thewell-known resonant shunts, consisting of resistan-ces, inductances and maybe negative capacitancesconnected to the piezoelectric element. This paper

presents a combined approach which is based on aconventional tuned mass absorber, but whose cha-racteristics can be strongly influenced by applyingshunted piezoceramics. Thus the tuning frequencyof the absorber can be adapted to the excitation fre-quency, without the need of much actuation powerand the damping characteristics of the absorber canbe changed.

Curriculum Vitae:

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D. O. Solovyeva : Purple Membranes as Promising Biomaterial for Photovoltaic Devices

Author: D. O. Solovyeva1, I. Nabiev1, S. Yu. Zaitsev1,21 Moscow Engineering Physics Institute (Russia) 2 Moscow State Academy of Veterinary Medici-ne and Biotechnology (Russia)E-Mail: [email protected], [email protected]: biomaterial, photovoltaic cell, purple membranes, bacteriorhodopsin, quantum dots

Preparation of the photovoltaic cells based onphotosensitive membrane protein - bacteriorho-dopsin is a rapidly growing field at the interfaceof biochemistry and nanobiotechnology, cell andmolecular biology. Purple membranes (PMs) arethe fragments of membranes of the bacteria Hal-obacterium salinarum, in which bacteriorhodopsinis the main protein component. Bacteriorhodopsinis transforming physical energy (light quanta) intochemical energy of macroergic compounds (e.g.,ATP) or mechanical energy (e.g., flagellar move-ment in bacteria). Bacteriorhodopsin and PMs pos-sesses unique physicochemical properties and ful-fils three main molecular functions that are crucialin terms of fundamental studies and technologi-cal applications: photoelectric, photochromic, andproton-transporting.

The optimisation of hybrid material efficiencyshould include development of highly oriented hy-brid films with enhanced light harvesting, energytransfer, photovoltaic, and optical switching pro-

perties. Such materials can be optimised by usingquantum dots (QDs) with stronger absorptions.

The ”dried” photovoltaic cells based on orientedPM (with or without QDs) located between the op-tically transparent electrodes were obtained. Theiroptical properties were examined by absorptionspectroscopy and fluorescent spectroscopy using apicosecond laser and one- and two-photon excitati-on; as well as their current-voltage characteristicswere estimated by self-made setup. The systemPM-QD530PEG−OH had better parameters in the”dried” photovoltaic cell then system PM-QD530Cysbut both less stable than standard system based onoriented PM films. Furthermore, the biotechnologi-cal approach using site-directed mutagenesis per-mits fine adjustment of biophotonic and biophoto-voltaic functionalities of proteins, thus enabling thedevelopment of hybrid nano-biomaterials with con-siderably improved functions useful for optical swit-ching and photovoltaic applications.

Curriculum Vitae:

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T. Ware : Softening Electronics For in Vivo Energy Harvesting Applications

Author: Taylor Ware1,2, Dustin Simon1, Robert Rennaker1, Walter Voit1,21 UT Dallas (United States)2 Syzygy Memory Plastics (United States)E-Mail: [email protected], [email protected], [email protected],[email protected]:

Seeking chronically stable biotic-abiotic interfaceshas driven technological development towards use-ful systems that can manipulate sensory and inputinformation without adversely affecting surroundingtissue and systems. To this end, specialized energyharvesting systems are required to power the nextgeneration of implantable softening bioelectronics,which promise to significantly advance how we dia-gnose and treat neurological disorders, understandbehavior and remedy underlying causes of mentalillnesses and neurodegenerative diseases. Implan-table neural interfaces enable communication withthe central and peripheral nervous system: both toinput and extract information, and rely on powersources to supply excitory signals and transmit sen-sory information.We demonstrate how the thermomechanical proper-ties of smart polymer substrates can be specifically

tuned to address critical problems in neural interfa-ces, when coupled with the ability to fabricate com-plex 3-D structures using cost-effective, well-studiedphotolithographic approaches. Using the shape me-mory effect, we show how standard lithographic pro-cessing on (temporarily) flat surfaces can recover(permanently) to new complex shapes. We explo-re the effectiveness of photolithographically patter-ned flexible electronics based on shape memorypolymers for a variety of bioengineering applicati-ons such as neural brain probes, flexible transistors,flexible antennas, cell culture dishes, cochlear im-plants and flexible prosthetics. These efforts unlocknew design paradigms for next generation energyharvesting systems with high reproducibility and theability to deform around complex shapes, with a fo-cus on devices inside the body.

Curriculum Vitae:

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M. S. Woo : Relationship Between Current and Impedance in Piezoelectric EnergyHarvesting System for Water Waves

Author: Min Sik Woo, Ki Hwan Baek, Jung Hun Kim, Se Bin Kim, Daniel Song, Tae Hyun SungHanyang University (South Korea)E-Mail: [email protected]@hanyang.ac.krKeywords: Piezoelectric, Energy Harvesting, Current, Impedance, Parallel

Energy harvesting system using piezoelectric de-vice has low output power because output currentis lower than high output voltage. So, it is necessaryto increase output current of piezoelectric device forscavenging more output power.

We investigated the method which obtains hig-her output power by increasing output current ofpiezoelectric energy harvesting system. The systemused in this experiment was designed with free endof cantilever-shaped piezoelectric device which wasconnected to vibration shaker. So, the strain couldbe controlled by adjusting the displacement of can-tilever free end. In order to measure the output cur-

rent of the piezoelectric energy harvesting system,the impedance of piezoelectric device was measu-red by impedance matching. First, to increase theoutput current, the strain of piezoelectric device wasmodified. The relationship between strain and cur-rent was found on the basis of the changing out-put voltage and impedance with strain of piezoelec-tric device. Another way to increase the output cur-rent of piezoelectric energy harvesting system wasthat connecting the piezoelectric devices in paral-lel. When the piezoelectric devices were connectedin parallel, the output current and the output powerwere increased due to the decreased combined im-pedance.

Curriculum Vitae:

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Y. Yang : Design of Small Piezoelectric Windmills for Different Load Types and WorkingConditions

Author: Ying Yang, Jiamei Jin, Qinlong ShenNanjing University of Aeronautics and Astronautics (China)E-Mail: [email protected]: unimorph/bimorph transducers

Designs of piezoelectric windmills with uni-morph/bimorph transducers are demonstrated forthe purpose of harvesting the power from freelyavailable wind on small scale. The basic designuses piezoelectric unimorph/bimorph cantilevers toform an enclosing polygon with elastic balls inside.The polygon is inscribed with the circumference ofthe mill. When the balls moving under the force ofgravity and the vibration of piezoelectric ceramics,they hit the piezoelectric transducers and generateelectricity. The structure is expecting to have the ad-vantage of low wear and tear, high output power andhigh efficiency. Several new designs with modifyingstructures facing different working conditions are gi-ven below. Firstly, if a transducer is designed to beimpacted on its free end and the first bending modeis excited, the output frequency will be localized andthe output voltage is optimized to maximum amplitu-

de with relatively stable frequency. Secondly, whenthe load is not LED, the rectification, filtering and sto-rage stages will usually be necessary. In this way,the piezoelectric transducers are better to be fixedand have simple wiring. A new structure is given thatthe rotating of the central shaft drives the balls to im-pact the piezoelectric transducers which are seatedon the edge of circumference as one side of poly-gon. Thirdly, in some occasion where simple struc-ture and light-weight is needed, a flexible wheel ofpiezoelectric composite forms a ring and rolling ballsare fixed in the inner edge of the ring’s radius. Elec-tric charge come out when the rolling balls press thepiezoelectric composite ring. When the piezoelectricphase in the composite is small enough, the outputvoltage will have small enough ripple wave. No rec-tification and filtering are needed in this design.

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T. Yang : Broadband Piezoelectric Energy Harvesting Using Piezoelectric Array

Author: Tongqing Yang, Wei Wang, Zhao Xiao, Xi YaoTongji University (China)E-Mail: [email protected]: Piezoelectric energy harvesting, Array, Broadbrand, Vibration

Harvesting electric energy from mechanical vibra-tion using a mechanically excited piezoelectric cir-cular membrane array is presented in this paper.The piezoelectric circular diaphragm array is con-sisted of four plates with series and parallel connec-tion, and the electrical characteristics of the arrayare examined under dynamic conditions. With anoptimal load resistor of 160 kΩ, an output powerof 28 mW was generated from the array in seriesconnection at 150 Hz under a pre-stress of 0.8 Nand a vibration acceleration of 9.8 m/s2, while a ma-ximal output power of 27mW can be obtained fromthe array in parallel connection through a resistive

load of 11 kΩ under the same condition (frequen-cy, pre-stress, acceleration). The results show thatusing a piezoelectric circular diaphragm array canincrease significantly the output of energy comparedwith the use of a single plate. By choosing an appro-priate connection pattern (series or parallel connec-tions) among the plates, the equivalent impedanceof the energy harvesting devices can be tailored tomeet the matched load of different applications formaximal power output. For broadband piezoelectricenergy harvesting, piezoelectric array with differentpre-stress is demonstrated.

Curriculum Vitae:

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C. H. Yang : Study on Piezoelectric Energy Harvesting System for Applying Vibration ofCommercial Trains in Korea

Author: Chan ho Yang, Seong Kwang Hong, Hyun Jun Jung, Ki Hwan Baek, Min Sik Woo, TaeHyun SungHanyang University (South Korea)E-Mail: [email protected], [email protected]: Piezoelectric energy harvesting, Acceleration, Displacement, Random vibration,Commercial train

We have studied piezoelectric energy harvestingusing generated vibration from train and investiga-ted the relationship between vibration accelerationand displacement of piezoelectric device. Additio-nally, we established the relationship between dis-placement of piezoelectric device and output power.The piezoelectric module was designed and manu-factured to maximize the output power by adjustingthe resonant frequency of the module which wasmatched with the regular vibration having uniformfrequency. However, it is very difficult to apply me-thod as mentioned above in random vibration suchas vibration of commercial train. Therefore, it is ne-cessary to find the frequency to maximize outputpower from the piezoelectric device.

We selected trains for experiment including com-mercial trains (Subway, ITX-Cheongchun and Noor-iro) and train to be scheduled for commercialization(Korean advanced urban trains) in Korea. First, vi-bration was measured inside running trains, and itwas analyzed in various ways. And we deducted

the most efficient frequency, i.e. the frequency tomaximize the displacement of piezoelectric devicein piezoelectric energy harvesting at each train onthe basis of analyzed results. And then optimizedpiezoelectric energy harvesting module was manu-factured for the most efficient frequency obtainedfrom the previous analysis. Finally, designed pie-zoelectric module was applied to each commercialtrain.

In case of Korean advanced urban train, the maxi-mum vibration acceleration was 923 mm/s2 at 72 Hzin z-axis of floor of car 1. Using the value, we pro-duced piezoelectric module with ceramic (45 x 35 x0.16 mm3) with resonant frequency is 70 Hz, so theoutput of applying the ceramic on the train vibrationincluding the maximum vibration acceleration was2.8 V. The output of modules applying to each com-mercial train will be presented. This research couldbuild the foundation stone of development of piezo-electric energy harvesting using vibration of com-mercial train.

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S. Y. Zaitsev : Hybrid Materials Based on Photosensitive Membrane Proteins for EnergyConversion Applications

Author: S. Yu. Zaitsev1,2, D. O. Solovyeva1, I. Nabiev11 Moscow Engineering Physics Institute (Russia) 2 Moscow State Academy of Veterinary Medici-ne and Biotechnology (Russia)E-Mail: [email protected]@mail.ruKeywords: energy harvesting, nanomaterials, bacteriorhodopsin, nanoparticles

The energy harvesting in plants has a maximumefficiency of 5%, whereas bacteriorhodopsin, in theabsence of a specific light-harvesting system, al-lows bacteria to utilize less than 0.5% of the so-lar light. Recent nano-bioengineering approachesemploying quantum dots (QDs) conjugated withphotosensitive proteins permit the enhancement ofthe light-harvesting capacity of such systems, thusproviding a strong impetus to the development ofprotein-based devices [1, 2]. Here, we demonstra-te advanced approaches to engineering of highlyorganized, oriented films from photosynthetic reac-tion centres or purple membranes of Halobacteri-um salinarum containing the photosensitive proteinbacteriorhodopsin [3]. Such ultrathin, highly orien-ted films may be regarded as prototypes of hybridnano-biomaterials with photovoltaic, energy trans-fer, and optical switching properties. Having compa-red different techniques for obtaining thin films with

homogeneity and orderliness sufficient for industri-al applications, we have shown that electrophoreticsedimentation provides the best results [3].

A possible approach to properties optimisation ofhybrid materials consisting of photosensitive biolo-gical systems and nanoparticles is to use nanowi-res or nanorods instead of QDs. Furthermore, thebiotechnological approach using site-directed mu-tagenesis permits fine adjustment of biophotonicand biophotovoltaic functionalities of proteins, thusenabling the development of hybrid nano-bio mate-rials with considerably improved functions useful foroptical switching and photovoltaic applications.

[1] I. Nabiev, A. Rakovich, A. Sukhanova, et al. Angew.Chem. Int. Ed. 49 (2010) 7217-7221.[2] A. Rakovich, A. Sukhanova, E. Lukashev, et al. NanoLett. 10 (2010), 2640-2648.[3] S.Yu. Zaitsev, D.O. Solovyeva, I. Nabiev. Adv. ColloidInterface Sci. 183-184 (2012) 14-29.

Curriculum Vitae: Sergey Zaitsev graduated from the Department of Chemistry of Moscow StateUniversity in 1980. From 1980 to 1999 Sergey Yu. Zaitsev worked at different positions (froma junior research assistant to an acting director of laboratory) in the Shemyakin-OvchinnikovInstitute of Bioorganic Chemistry of the Russian Academy of Sciences, Moscow. Since 1st Sep-tember 1999, Sergey Yu. Zaitsev has been working as the head of the Organic and Biologi-cal Chemistry Department of the Skryabin Moscow State Academy of Veterinary Medicine andBiotechnology (MSAVMB); since 2006 and 2009 he has also been the scientific director of theInnovation-Research Center and the Research-Education Center of the MSAVMB, respectively,.The State Commission for Academic Degrees and Titles of the Russian Federation awarded Ser-gey Yu. Zaitsev a Doctor of Science degree in bioorganic chemistry and high-molecular-weightcompounds in 1995 (certificate DK no. 001835 issued on 5 May 1995). A full professorship at theOrganic and Biological Chemistry Department of the MSAVMB was approved by the commissionin 2005 (certificate PR no. 012113 issued on 16 March 2005). In 2007, Prof. Zaitsev receivedhis second Doctor of Science degree in biochemistry (certificate DDN no. 005161 issued on 5October 2007).

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Energie Harvesting

H. Zessin : Modeling of Hybrid Piezoelectrodynamic Generators

Author: Henrik Zessin,Fraunhofer Institute for Integrated Circuits IIS (Germany)E-Mail: [email protected]: Energy Harvesting, modeling, electrodynamic generator, piezoelectric generator,hybrid

Increasing the power density of vibrational ener-gy harvesting generators is a key aspect in the de-velopment of more sophisticated self-powered devi-ces. A promising concept is the combination of pie-zoelectric and electrodynamic generators in a hybridor coupled device. A piezoelectric cantilever beamcan be equipped with a magnet at the tip instead of aregular proof mass. By adding a coil around the ma-gnet, the generator now works with two conversionprinciples, the piezoelectric and the electromagneticeffect. It has been reported, that the power outputof such a coupled device exceeds the power outputof an individual generator with only one conversi-on principle (Challa, Prasad, & Fisher, 2009). Alsomultimodal harvesting at different resonant frequen-cies can be achieved by a hybrid device (Tadasse,Zhang, & Priya, 2009). Although this kind of devicehas already been studied, there is no comprehensi-ble model of the generator. By using electromecha-

nical analogies, a lumped equivalent circuit modelcan be derived for the coupled generator. This ar-ticle proposes an electromechanical model for hy-brid piezoelectrodynamic generators. This model al-lows the simulation of a combined electrodynamicand piezoelectric generator and understanding theinfluence of changing mechanical properties of thedevice such as mass, flexibility or damping in theelectrical harvested power. The specific parametersof the hybrid generator can be optimized by simula-ting the electronic load with the lumped equivalentcircuit. With this equivalent circuit model of the ge-nerator, it is possible to investigate the use of non-linear or active rectifiers. It allows the developmentand electrical simulation of control strategies for theactive circuit to extract the maximum power from thegenerator and in that way increase the power densi-ty of the whole energy harvesting system even fur-ther.

Curriculum Vitae: Henrik Zessin studied Mechatronics at the University of Erlangen \Germanyand graduated with a Dipl.-Ing. degree in 2010. Since 2010, he works for the Fraunhofer IIS in thepower efficient systems department. He is a project manager in the ?integrated energy supplies?group where he is doing research and design on the field of power and battery management,energy transmission and energy harvesting. The focus of his research lies in the field of powermanagement for electrodynamic energy harvesting devices.

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Table of Contents

C. L. Zhang : Magnetoelectric Effects in Functionally Graded Multiferroic Bilayers

Author: C. L. Zhang1,2, W. Q. Chen2 and Ch. Zhang1

1 University of Siegen (Germany) 2 Zhejiang University (China)E-Mail: [email protected], [email protected], [email protected]: Magnetoelectric Effect, Magnetic Harvester, FGM, FGPP Bilayers

Functionally graded materials (FGMs), which pos-sess a graded property distribution in space alongcertain directions, are optimal composite materialsfor satisfying some special requirements of devices.Some novel phenomena may arise in functionallygraded ferroelectric/ferromagnetic bilayers or mul-tiferroic composites, which offer new concepts andpossibilities in the design of magnetoelectric (ME)devices. In this contribution, we present an analy-tical model to evaluate the magnetoelectric effectsin functionally graded multiferroic laminated plates.

The static and frequency-dependent ME effects infunctionally graded piezoelectric and piezomagnetic(FGPP) bilayers with different gradation of the mate-rial property along the thickness are analyzed. In ad-dition, a magnetic energy-harvester made of FGPPbilayers is also modeled and investigated. The re-sults show that the FGPP bilayers with a specialmaterial gradation have a stronger ME coupling ef-fect than that in the homogeneous structure. Conse-quently, the FGPP harvesters can achieve a largeroutput power.

Curriculum Vitae:

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Energie Harvesting

H. Zou : Simulation Analysis of the Piezoelectric Microgenerator from Vibration inducedby Acoustic

Author: Huajie Zou, Hejuan ChenNanjing University of Science and Technology (China)E-Mail: [email protected]: Piezoelectric Microgenerator, vibration induced by acoustic, Lumped elements,Acoustic characterization

This paper presents the development of a Pie-zoelectric Microgenerator from vibration induced byacoustic for aeroacoustic application. The Piezo-electric Microgenerator contains an air inlet, wherea cylindrical plug centrally located forming an annu-lar orifice, and an electromechanical resonator. Theelectromechanical resonator consists of a neck, abacking cavity and a compliant piezoelectric com-posite diaphragm. Through the air inlet, airflow ge-nerates vortex behind the plug and then develops tosound. Acoustic energy is converted to mechanicalenergy when sound incident on the neck generatesan oscillatory pressure in the backing cavity, whichin turns causes the vibration of the diaphragm. Theconversion of acoustic energy to electrical energyis achieved via piezoelectric transduction in the dia-phragm of the electromechanical resonator. Moreo-ver, the diaphragm is coupled with energy reclama-tion circuitry to increase the efficiency of the con-version. The underlying technical concept is basedon the idea that the fundamental frequency of theelectromechanical resonator may be adjusted withthe piezoelectric composite diaphragm coupled to

a passive electrical network. Therefore, characteri-zation of the electromechanical resonator is crucialfor the Piezoelectric Microgenerator. In this paper,an electromechanical resonator containing a com-pliant aluminum diaphragm is investigated to pro-vide a fundamental understanding of this system,before adding complexity via the piezoelectric com-posite material. This paper analyzes characteriza-tion of the electromechanical resonator theoretical-ly. The dynamics of the system are modeled usinglumped elements and are represented in an equi-valent electrical circuit. With basic methods for cir-cuit analysis, the transfer function and acoustic inputimpedance of the system are derived. The acousticcharacterization of the electromechanical resonator,which is significantly influenced by the main structu-ral parameters including the length of the neck, theradius of the neck, the length of the backing cavi-ty, the radius of the diaphragm and the thickness ofthe diaphragm, is simulated and analyzed. These si-mulations draw some meaningful conclusions andserve as references for the design of PiezoelectricMicrogenerator from vibration induced by acoustic.

Curriculum Vitae: Education: 2010-present Nanjing University of Science and Technology Ph.D.(M.S.-Ph.D. combined), Mechatronics Concentrations: Piezoelectric Microgenerator2006-2010 Nanjing University of Science and Technology B.S., Mechanical Engineering Rese-arch Interests: Piezoelectric Microgenerator designFluid power source

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IWPMA & EHW · 2013-06-12 · 10 th International Workshop on Piezoelectric Materials and...

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