Work Report

Speaker : You LinAdvisor : Chen Gang

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Y• Literature reading

N• Mini Bath

ING• Literature/Design

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The development of biological mechanics

List applications

Introduces the research of tendon

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The development of biological mechanics

When ?

Leonardo Da Vinci: he was interested in a means by which man could fly and thus he studied the flight of birds.

Bionics: Applying biological principles to the study and design of engineering systems

Galileo Galilei: interested in the strength of bones and suggested that bones are hollow for this affords maximum

strength with minimum weight.Biological optimization

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When ?

The development of biological mechanics

Y.C. Fung : 1966, The university of California(Yuan Cheng Fung) Department of Bioengineering

1. The research of the constitutive relation of biological soft tissue

2. The research of pulmonary blood flow law

3. The research of growth and stress relationship of biological tissue and organ

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The development of biological mechanics

What?

Biomechanics : ”mechanics applied to biology”

The development, extension and application of mechanics for the purposes of understanding better physiology and pathophysiology as well as the diagnosis and treatment of disease and injury.

That is, the overall goal of biomechanics is, and must remain, the general improvement of the human condition.

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Bio-

nonlinear、 ­finite­elasticity,­viscoelasticity、mixture­theory

-----theoretical framework Equipment

Basic life sciences

Need

MathematicsMechanics

The development of biological mechanics

Computer

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The development of biological mechanics

Journal:the Journal of Biomechanics(1968)the ASME Journal of Biomechanical Engineering(1977)Computer Methods in Biomechanics and Biomedical Engineering(1998)Biomechanics and Modeling in Mechanobiology(2002)…the Annals of Biomedical Engineeringthe IEEE Transactions for Biomedical Engineering

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Three general areas of study:

Solution of initial-boundary-value problems of academic, industrial and clinical importance

Formulation of constitutive relations that describe material behavior

Identi fication of fundamental concepts, postulates and principles

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Five basic steps in the formulation of a constitutive: -------DEICE

DEICE

delineation of general characteristics of interest

establishing an appropriate theoretical framework for quantification

identification of specific functional forms of the constitutive relations

calculation of the values of the associated material parameters

evaluation of the predictive capability of the final relation

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Application

How will humans respond to the altered loads associated with space travel?

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ApplicationBiomechanics aims to explain the mechanics of life and living. From molecules to organisms, everything must obey the laws of mechanics.

• from the design of a vehicle with improved crashworthiness, to the design of a wheelchair;

(Optimization design, humanization design)

• from the design of a left ventricular assist device to aid a failing heart, to the design of an intraocular implant to improve vision;

(Supplementary)

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• from predicting which diagnosed aneurysm is at risk of rupture, to identifying the failure strength of an anterior cruciate ligament in an elite athlete, which must be protected during training and competition;

(Evaluation)• from designing an artificial heart valve that must open and

close over 30 million times per year, to designing a biologically coated intravascular stent device to prevent restenosis;

(Design bio-)• from using computer-aided modeling to guide plastic surgery,

to designing catheters that induce less denudation damage;

Application

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• from designing a mechanical ventilator to support patients in respiratory distress, to specifying rehabilitation schedules that promote tissue healing;

(Systematization)• from quantifying brain properties that enable robotic-assisted

surgery, to designing improved procedures in surgical specialties;

(automation)• from the engineering of tissue for surgical replacement, to the

development of an improved interpretation of ultrasound images and hundreds of applications in between.

(assistant technology/ substitute)

Application

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TendonR.F. Ker. 1981 , The plantaris tendon of sheep : design of clamp and extensometer , modulus, dissipates, frequencies, temperature

R.F. Ker, N.J. Dimery, R.M. Alexander. 1986, wallaby : clamp, The photographic method, modulus, bending tests

X.T. Wang, M.R. Ruister, R. Alexander, R.F. Ker. 1991, mammalian tail tendons : Temperature

R.F. Ker. 1999, Soft Collagenous Load-Dearing Tissues: design, tendon, cartilage, heel pad, stress-strain, micromechanics

T.A.L. Wren, S.A. Yerby, G.S. Beaupré, D.R. Carter. 2000, calcaneus : Dual-Energy X-Ray absorptiometry measurements, the Assessment of Osteopenia and Fracture Risk

T.A.L. Wren, S.A. Yerby, G.S. Beaupré, D.R. Carter. 2001, human achilles tendon: 1%、 10%/s strain rate, modulus, failure stress/strain

T.A.L. Wren, S.A. Yerby, G.S. Beaupré, D.R. Carter. 2003, human achilles tendon: creep, cycle load, failure

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Tendon

Fig. 1. Principle of the measurements

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Tendon

LVDT

dural inner tube

a PTFE coat

the steel outer tube

The core

an extension rod

the screw

the wires

Pins

Fig. 2. The extensometer

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Tendon

Fig. 3. The two types of clamp used in the investigation

19861981

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Tendon

Fig. 4. The heating cylinder, which was filled with liquid paraffin to prevent the tendon drying and to improve heat transport. The cylinder is placed over the lower clamp and screwed to the actuator.

1991

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Tendon

Fig. 5. Experimental setup

2001 2003

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Tendon

Fig. 6. Typical stress - strain relation

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Tendon

Fig.7. Stress distribution in fibre and matrix for discontinuous fibre reinforcement

The Cox’s theory

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Tendon

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Appendix[1] G.A. Holzapfel . Biomechanics of Soft Tissue. Computational Biomechanics[J], 7(2000):1~12[2] J.D. Humphre. Review Paper: Continuum Biomechanics of Soft Biological Tissues. Proceedings of the Royal Society of society[J]. A(2003):1~46[3] T.A.L. Wren, S.A. Yerby, G.S. Beaupré, D.R. Carter. Interpretation of Calcaneus Dual-Energy X-Ray Absorptiometry Measurements in the Assessment of Osteopenia and Fracture Risk. Journal of Bone and Material Research[J]. 15(2000):1573~1578[4] T.A.L. Wren, S.A. Yerby, G.S. Beaupré, D.R. Carter. Mechanical Properties of the Human Achilles Tendon. Clinical Biomechanics[J], 16(2001):245~251[5] T.A.L. Wren, S.A. Yerby, G.S. Beaupré, D.R. Carter. Effects of Creep and Cyclic Loading on the Mechanical Properties and Failure of Human Achilles Tendons. Annals of Biomedical Engineering[J], 31(2003):710~717[6] R.F. Ker. Dynamic Tensile Properties of The Plantaris Tendon of Sheep(Ovis aries). The Journal of Experimental Biology[J], 93(1981):283~302[7] R.F. Ker, N.J. Dimery, R.M. Alexander. The Role of Tendon Elasticity in Hopping in a Wallaby (Macropus Rufogriseus). Journal of Zoology[J], 208(1986):417~428[8] X.T. Wang, M.R. Ruister, R. Alexander, R.F. Ker. The Effect of Temperature on the Tensile Stiffness of Mammalian Tail Tendons. Journal of Zoology[J], 223(1991):491~497[9] R.F. Ker. The Design of Soft Collagenous Load-Dearing Tissues. The Journal of Experimental Biology[J], 202(1999):537~548

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thank you for your attention!