H. Janocha (Ed.)

Actuators Basics and Applications

With 303 Figures and 47 Tables

Springer

Contents

1 Introduction Hartmut Janocha 1 1.1 What is an Actuator? 1 1.2 Actuator as a System Component 3 1.3 Actuators in the Fields of Mechatronics and Adaptronics 5 1.4 "Intelligent" and Self-Sensing Actuators 8

1.4.1 "Intelligent" Solid-state Actuator 9 1.4.2 Self-sensing Solid-state Actuator 10

Operator-based Modelling for Large-signal Operation . . . . 11 Reconstruction and Compensation Filter 11 Example Application: Piezoelectric Positioning System . . . 12

1.5 Design of Actuators 13 References 17

2 Power Circuits Stefan Butzmann 19 2.1 Introduction 19 2.2 Power Switching Devices 20

2.2.1 Overview 20 2.2.2 Power Diode 22 2.2.3 Bipolar Power Transistor 24 2.2.4 Power-MOSFET 28

Static Behavior 28 Dynamic Characteristics 31

2.2.5 IGBT 33 2.2.6 Thyristor 36

2.3 Drive Circuits for MOS-gated Devices 37 2.3.1 General Remarks 37 2.3.2 Low-side Drive Circuits 39 2.3.3 High-side Drive Circuits 41

Drive Circuits for p-channel MOSFETs 41 Bootstrap Drivers for n-channel MOSFETs 42 Charge Pumps 44

XI I Contents

Static and Dynamic Behavior 184 Open Loop of a Hydraulic Drive 185

4.4.2 Pneumatic Motors 186 Rotary Motors 186 Translatory Motors 186 Static and Dynamic Performance 186

4.5 Sensors 192 4.5.1 Pressure Sensors 193 4.5.2 Flow Sensors 195 4.5.3 Position and Rotary Sensors 196

4.6 Controller Types 197 4.6.1 Control of Hydraulic Servo Systems 198 4.6.2 Single-loop Control 199 4.6.3 Multi-loop Controls 200 4.6.4 Formulation of Control Design 202

Linear Method 202 Non-linear Additional Functions 205

4.6.5 Control of Pneumatic Servo Systems 206 Position Control 206 Pressure Control 211

4.6.6 Realization of Controls with Microcomputers 212 4.7 The Fluidpower Drive as a Subsystem 214 4.8 Comparison Between Fluidpower and Electric Drives 215

Comparison of Characteristics 215 Advantages and Disadvantages of Fluidpower Actuators . . 216

4.9 Application Examples 217 4.9.1 Automatic Anti-lock Braking System 217 4.9.2 Servopneumatic Drives for Handling Systems 219 4.9.3 Pneumatic Grippers 220 4.9.4 Simulation of Motion 222 4.9.5 Numerically-controlled Machine Tool 224 4.9.6 Application and Operating Conditions

of Theater Hydraulics 227 References 230

5 Unconventional Actuators Hartmut Janocha 233 5.1 Introduction 233 5.2 Electrochemical Actuator 234

5.2.1 Electrochemical Reactions 234 5.2.2 Technical Implementation 235 5.2.3 Application Examples 238 5.2.4 Development Trends 238

Contents XIII

5.2.5 Comparison to Competing Actuator Principles 239 Expansion Elements 239 Metal Hydride Actuator 240

3 Actuators with Shape Memory Alloys 241 5.3.1 Shape Memory Effect 241 5.3.2 Technical Implementation 244

Materials 244 Heating of Memory Components 245 Dimensioning of NiTi Components 246

5.3.3 Application Examples 249 Flap Operation 250 Model Making 250 Heavy Duty Actuator 251

5.3.4 Development Trends 252 5.3.5 Comparison to Competing Actuator Principles 252

4 Piezoelectric Actuators 254 5.4.1 Physical Effect 254 5.4.2 Technical Implementation 256

Materials 256 Design of Piezoelectric Transducers 260

5.4.3 Electronic Power Amplifier 270 5.4.4 Application Examples 273

Position Controlled Actuator Operation 273 Mirror Drive for Laser Gyro 274 Diesel Injector 275

5.4.5 Development Trends 276 5 Magnetostrictive Actuators 277

5.5.1 Physical Effect 277 5.5.2 Technical Implementation 278

Materials 278 Design of Giant Magnetostrictive Transducers 280

5.5.3 Electronic Power Amplifier 285 5.5.4 Comparison Between Piezoelectric

and Magnetostrictive Actuators 286 5.5.5 Application Examples 288

Underwater Sonar System 288 Dynamic Vibration Absorber 289 Hybrid Actuator 290

5.5.6 Development Trends 292 6 Actuators with Electrorheological Fluids 292

5.6.1 Physical Effect 292 5.6.2 Technical Implementation 294

Materials 294 Design of Energy Transducers with ER Fluids 298

XIV Contents

5.6.3 Electronic Power Amplifier 299 5.6.4 Application Examples 301

Positioning Drive 301 Tactile Element 302 Shock Absorber 303

5.6.5 Development Trends 306 5.7 Actuators with Magnetorheological Fluids 306

5.7.1 Physical Effect 306 5.7.2 Technical Implementation 307

Materials 307 Design of Energy Transducers Based on MR Fluids 310

5.7.3 Electronic Power Amplifier 313 5.7.4 Comparison Between ER and MR Fluid Actuators 315 5.7.5 Application Examples 316

Brake 316 Clutch 317 Motor Mount 319

5.7.6 Development Trends 320 5.8 Microactuators 320

5.8.1 Principle 320 5.8.2 Realization 321 5.8.3 Application Examples 322

Microdrives 322 Positioning and Gripper Systems 325 Microoptics 328 Microfluidics 329

5.8.4 Development Trends 333 References 334

Index 337