MECHATRONICS SABRI CETINKUNT University of Illinois at Chicago WILEY JOHN WILEY & SONS, INC.
CONTENTS PREFACE vii CHAPTER 1 INTRODUCTION TO MECHATR0N1CS 1 1.1 Introduction 1 1.2 Case Study: Modeling and Control of Combustion Engines 13 1.2.1 Diesel Engine Components 14 l.2.2 Engine Control System Components 20 1.2.3 Engine Modeling with Lug Curve 22 1.2.4 Engine Control Algorithms: Engine Speed Regulation Using Fuel Map and a Proportional Control Algorithm 26 1.3 Problems 26 CHAPTER 2 CLOSED-LOOP CONTROL 29 2.1 Components of a Digital Control System 30 2.2 The Sampling Operation and Signal Reconstruction 32 2.2.1 Sampling: A/D Operation 32 2.2.2 Sampling Circuit 32 2.2.3 Mathematical Idealization of the Sampling Circuit 34 2.2.4 Signal Reconstruction: D/A Operation 39 2.2.5 Real-Time Control Update Methods and Titne-Delay 42 2.2.6 Filtering and Bandwidth Issues 44 2.3 Open-Loop Control versus Closcd-Loop Control 46 2.4 Performance Specifications for Control Systems 49 2.5 Time Domain and s-domain Correlation of Signals 51 2.5.1 Selection of Pole Locations 52 2.5.2 Step Response of a Seeond-Order System 52 2.5.3 Standard Filters 56 2.5.4 Steady-State Response 56 2.6 Stability of Dynamic Systems 58 2.6.1 Bounded Input-Bounded Output Stability 59 2.7 The Root Locus Method 60 2.8 Basic Feedback Control Typcs 64 2.8.1 Proportional Control 67 2.8.2 Derivative Control 68 2.8.3 Integral Control 69 2.8.4 PI Control 70 2.8.5 PD Control 72 2.8.6 PID Control 73 2.9 Translation of Analog Control to Digital Control 74 2.9.1 Finite Difference Approximations 76 2.10 Problems 78 CHAPTER 3 MECHANISMS FOR MOTION TRANSMISSION 81 3.1 Introduction 81 3.2 Rotary-to-Rotary Motion Transmission Mechanisms 84 3.2.1 Gears 84 3.2.2 Belt and Pulley 85 3.3 Rotary-to-Translational Motion Transmission Mechanisms 87 3.3.1 Lead Screw and Ball Screw Mechanisms 87 3.3.2 Rack-and-Pinion Mechanism 89 3.3.3 Belt and Pulley 90 3.4 Cyclic Motion Transmission Mechanisms 91 3.4.1 Linkages 91 3.4.2 Cams 92 3.5 Shaft Misalignments and Flexible Couplings 101 3.6 Actuator Si/.ing 102 3.6.1 Inertia Match Between Motor and Load 108 3.7 Homogeneous Transformation Matrices 110 3.8 Problems 119 CHAPTER 4 MICROCONTROLLERS 123 4.1 Embeddcd Computers versus Nonembeddcd Computers 123 4.1.1 Design Steps of an Embedded Microcontroller-Based Mechatronic System 125
IV CONTENTS 4.1.2 Microcontroller Development Tools 125 4.1.3 Microcontroller Development Tools t'orpic 18F452 127 4.2 Basic Computer Model 129 4.3 Microcontroller Hardware and Software: PIC 18F452 133 4.3.1 Microcontroller Hardware 133 4.3.2 Microproccssor Software 137 4.3.3 I/OPeripheratsofPIC I8F452 139 4.4 Interrupts 145 4.4.1 General Features of Interrupts 145 4.4.2 Interrupts on PIC 18F452 147 4.5 Problems 152 CHAPTER 5 ELECTRONIC COMPONENTS EOR MECHA TRONIC S YSTEMS 153 5.1 Introduction 153 5.2 Basics of Linear Circuits 153 5.3 Equivalcnt HIectrical Circuit Methods 156 5.3.1 Thevenin's Equivalcnt Circuit 157 5.3.2 Norton's Equivalent Circuit 157 5.4 Impedance 160 5.4.1 Concept of Impedance 160 5.4.2 Amplilier: Gain. Inpul Impedance, and Output Impedance 163 5.4.3 Input and Output Loading Errors 164 5.5 Semiconductor Electronic Devices 166 5.5.1 Semiconductor Materials 166 5.5.2 Diodes 168 5.5.3 Transistors 172 5.6 Operational Amplifiers 183 5.6.1 Basic Op-Amp 184 5.6.2 Common Op-Amp Circuits 188 5.7 Digital Electronic Devices 201 5.7.1 Logic Devices 201 5.7.2 Decoders 202 5.7.3 Multiplexcr 202 5.7.4 Flip-Flops 204 5.8 Digital and Analog I/O and Thcir Computer Interface 206 5.9 D/A and A/D Converters and Their Computer Interface 208 5.10 Problems 214 CHAPTER 6 SENSORS 217 6.1 Introduction to Measurement Devices 217 6.2 Measurement Device Loading Errors 220 6.3 Wheatstone Bridge Circuit 222 6.3.1 Null Method 223 6.3.2 Deflection Method 223 6.4 Position Sensors 225 6.4.1 Potentiometer 225 6.4.2 LVDT, Resolver. and Syncro 227 6.4.3 Encoders 232 6.4.4 Hall Effect Sensors 237 6.4.5 Capaeitive Gap Sensors 238 6.4.6 Magnetostriction Position Sensors 239 6.4.7 Sonic Distance Sensors 240 6.4.8 Photoelcctric Distance and Presence Sensors 241 6.4.9 Presence Sensors: ON/OFF Sensors 243 6.5 Velocity Sensors 245 6.5.1 Tachometers 245 6.5.2 Digital Derivation of Velocity from Position Signal 247 6.6 Acccleration Sensors 248 6.6.1 Inertial Accelerometers 249 6.6.2 Piezoelectric Accelerometers 252 6.6.3 Strain-Gauge-Based Accelerometers 254 6.7 Strain, Force, and Torque Sensors 254 6.7.1 Strain Gauges 254 6.7.2 Force and Torque Sensors 256 6.8 Pressure Sensors 259 6.8.1 Displacement-Based Pressure Sensors 260 6.8.2 Strain-Gauge-Based Pressure Sensor 261 6.8.3 Piezoclectric-Based Pressure Sensor 262 6.8.4 Capaeitance-Based Pressure Sensor 262 6.9 Temperaturc Sensors 263 6.9.1 Temperature Sensors Based on Dimensional Change 264 6.9.2 Temperature Sensors Based on Resistance 264 6.9.3 Thcrmocouples 265 6.10 Flow Rate Sensors 267 6.K). I Mechanical Flow Rate Sensors 267 6.10.2 Differential Pressure Flow Rate Sensors 269 6.10.3 Thermal Flow Rate Sensors: Hot Wire Anemometer 271 6.10.4 Mass Flow Rate Sensors: Coriolis Flow Meters 272 6.1 l Humidity Sensors 272 6.12 Vision Systems 273 6.13 Problems 277 CHAPTER 7 ELECTROHYDRA ULIC MOTION CONTROL SYSTEMS 281 7.1 Introduction 281 7.1.1 Fundamental Physical Principles 294
CONTENTS V 7.1.2 Analogy Between Hydraulic and Electrical Components 296 7.1.3 Energy Loss and Pressure Drop in Hydraulic Circuits 299 7.2 Hydraulic Pumps 301 7.2.1 Types of Positive Displacement Pumps 303 7.2.2 Pump Performance 307 7.2.3 Pump Control 313 7.3 Hydraulic Actuators: Hydraulic Cylinder and Rotary Motor 320 7.4 Hydraulic Valves 324 7.4.1 Pressure Control Valves 326 7.4.2 Example: Multifunction Hydraulic Circuit with Poppet Valves 330 7.4.3 Flow Control Valves 332 7.4.4 Example: A Multifunction Hydraulic Circuit Using Post-Pressure Compensated Proportional Valves 337 7.4.5 Directional Flow Control Valves: Proportional and Servo Valves 339 7.4.6 Mounting of Valves in a Hydraulic Circuit 351 7.4.7 Performance Characteristics of Proportional and Servo Valves 352 7.5 Sizing of Hydraulic Motion System Components 359 7.6 EH Motion Axis Natural Frequency and Bandwidth Limit 371 7.7 Linear Dynamic Model of a One-Axis Hydraulic Motion System 373 7.7.1 Position Controlled Electrohydraulic Motion Axes 375 7.7.2 Load Pressure Controlled Electrohydraulic Motion Axes 378 7.8 Nonlinear Dynamic Model of a Hydraulic Motion System 379 7.9 Current Trends in Electrohydraulics 381 7.10 Case Studies 384 7.10.1 Case Study: Multifunction Hydraulic Circuit of a Caterpillar Wheel Loader 384 7. II Problems 388 CHAPTER 8 ELECTRIC A CTUA TORS: MOTOR AND DRIVE TECHNOLOGY 393 8.1 Introduction 393 8.1.1 Stcady-State Torque-Speed Range. Regeneration, and Power Dumping 395 8.1.2 Electric Fields and Magnetic Fields 399 8.1.3 Permanent Masinetic Materials 412 8.2 Solenoids 423 8.2.1 Operating Principles of Solenoids 423 8.2.2 DC Solenoid: Electromechanical Dynamic Model 426 8.3 DC Servo Motors and Drives 430 8.3.1 Operating Principles of DC Motors 431 8.3.2 Drives for DC Brush-Type and Brushless Motors 438 8.4 AC Induction Motors and Drives 447 8.4.1 AC Induction Motor Operating Principles 448 8.4.2 Drives for AC Induction Motors 454 8.5 Step Motors 461 8.5.1 Basic Stepper Motor Operating Principles 463 8.5.2 Step Motor Drives 468 8.6 Switched Reluctance Motors and Drives 471 8.6.1 Switched Reluctance Motors 471 8.6.2 SR Motor Control System Components: Drive 475 8.7 Linear Motors 478 8.8 DC Motor: Electromechanical Dynamic Model 481 8.8.1 Voltage Amputier Drivcn DC Motor 484 8.8.2 Current Amplifier Driven DC Motor 485 8.8.3 Steady-State Torque-Speed Characteristics of a DC Motor under Constant Terminal Voltage 486 8.8.4 Steady-State Torque-Speed Characteristics of a DC Motor and Current Amplifier 486 8.9 Energy Losses in Electric Motors 488 8.9.1 Resistance Losses 489 8.9.2 Core Losses 490 8.9.3 Friction and Windage Losses 491 8.10 Problems 491 CHAPTER 9 PROCRAMMABLE LOGIC CONTROLLERS 495 9.1 Introduction 495 9.2 Hardware Components of PLCs 498 9.2.1 PLC. CPU, and I/O Capabilities 498 9.2.2 Opto-Isolated Discrete Input and Output Modules 502 9.2.3 Relays, Contactors, Starters 503 9.2.4 Counters and Timers 505 9.3 Programming of PLCs 505 9.3.1 Hardwired Seal-In Circuit 509 9.4 PLC Control System Applications 510
VI CONTENTS 9.5 PLC Application Example: Conveyor and Furnace Control 511 9.6 Problems 514 CHAPTER10 PROGRAMMABLE MOTION CONTROL SYSTEMS 515 10.1 lntroduction 515 10.2 Design Methodology l'or PMC Systems 520 10.3 Motion Controller Hardware and Software 521 10.4 Basic Single-Axis Motions 522 10.5 Coordinatcd Motion Control Methods 526 10.5.1 Point-to-Point Synchronized Motion 527 10.5.2 Electronic Gearing Coordinated Motion 528 10.5.3 CAM Profile and Contouring Coordinated Motion 531 10.5.4 Sensor-Based Real-Time Coordinated Motion 532 10.6 Coordinated Motion Applications 532 10.6.1 Web Handling with Registration Mark 532 10.6.2 Web Tension Control Using Electronic Gearing 535 10.6.3 Smart Conveyors 539 10.7 Problems 544 APPENDIX A TABLES 547 APPENDIX B MODELING AND SIMUIA T/ON OF D YNAMIC SYSTEMS 549 B.l Modeling of Dynamic Systems 549 B.2 Complex Variables 550 B.3 Laplace Transforms 552 B.3. l Definition of Laplace Transform 552 B.3.2 Properties of the Laplace Transform 554 B.3.3 Laplace Transforms of Some Common Functions 558 B.3.4 Inverse Laplace Transform: Using Partial Fraction Expansions 562 B.4 Fourier Series, Fourier Transforms, and Frequency Response 566 B.4.1 Basics of Frequency Response: Meaning of Frequency Response 571 B.4.2 Relationship Betwcen the Frequency Response and Transfer Function 572 B.4.3 s-domain Interpretation of Frequency Response 573 B.4.4 Experimental Determination of Frequency Response 574 B.4.5 Graphical Representation of Frequency Response 574 B.5 Transfer Function and Impulse Response Relation 574 B.6 Convolution 579 B.7 Review of Differential Equations 581 B.7.1 Definitions 581 B.7.2 System of First-Order O.D.E.s 581 B.7.3 Existence and Uniqueness of the Solution ofo.d.e.s 582 B.8 Linearization 583 B.8.1 Linearization of Nonlinear Functions 583 B.8.2 Linearization of Nonlinear First-Order Differential Equations 585 B.8.3 Linearization of Multidimensional Nonlinear Differential Equations 586 B.9 Numciical Solution ofo.d.e.s and Simulation of Dynamic Systems 588 B.9.1 Numerical Methods for Solving O.D.E.s 589 B.9.2 Numerical Solution ofo.d.e.s 589 B.9.3 Time Domain Simulation of Dynamic Systems 591 B. 10 Details of the Solution for Example on Page 162: RL and RC Circuits 600 B.ll Problems 604 B1BLIOGRAPHY 607 INDEX 611