Computer-controlled systems : theory and design / Karl J. Astrom, Bjorn Witternmark.

CONTENIDO
1. Computer Control 1
Computer Technology 2
Computer-Control Theory 11
Inherently Sampled Systems 22
How Theory Developed 25
2. Discrete-Time Systems 30
Sampling Continuous-Time Signals 30
Sampling a Continuous-Time State-Space System 31
Discrete-Time Systems 42
Changing Coordinates in State-Space System 44
Input-Output Models 46
The z-Transform 53
Poles and Zeros 61
Selection of Sampling Rate 66
Problems 68
3. Analysis of Discrete-Time Systems 77
Stability 77
Sensitivity and Robustness 89
Controllability, Reachability, Observability, and Detectability 93
Analysis of Simple Feedback Loops 103
Problems 114
4. Pole-Placement Design: A State-Space Approach 120
Control-System Design 121
Regulation by State Feedback 124
Observers 135
Output Feedback 141
The Servo Problem 147
A Design Example 156
Conclusions 160
Problems 161
5. Pole-Placement Design: A Polynomial Approach 165
A Simple Design Problem 166
The Diophantine Equation 170
More Realistic Assumptions 175
Sensitivity to Modeling Errors 183
A Design Procedure 186
Design of a Controller for the Double Integrator 195
Design of a Controller for the Harmonic Oscillator 203
Design of a Controller for a Flexible Robot Arm 208
Relations to Other Design Methods 213
Conclusions 220
Problems 220
6. Design: An Overview 224
Operational Aspects 224
Principles of Structuring 229
A Top-Down Approach 230
A Bottum-Up Approach 233
Design of Simple Loops 237
Conclusions 240
Problems 241
7. Process-Oriented Models 242
A Computer-Controlled System 243
Sampling and Reconstruction 244
Aliasing or Frequency Folding 249
Designing Controllers with Predictive First-Order Hold 256
The Modulation Model 262
Frequency Response 268
Pulse-Transfer-Function Formalism 278
Multirate Sampling 286
Problems 289
8. Approximating Continuous-Time Controllers 293
Approximations Based on Transfer Functions 293
Approximations Based on State Models 301
Frequency-Response Design Methods 305
Digital PID-Controllers 306
Conclusions 320
Problems 320
9. Implementation of Digital Controllers 324
An Overview 325
Prefiltering and Computational Delay 328
Nonlinear Actuators 331
Operational Aspects 336
Numerics 340
Realization of Digital Controllers 349
Programming 360
Conclusions 363
Problems 364
10. Disturbance Models 370
Reduction of Effects of Disturbances 371
Piecewise Deterministic Disturbances 373
Stochastic Models of Disturbances 376
Continuous-Time Stochastic Processes 397
Sampling a Stochastic Differential Equation 402
Conclusions 403
Problems 404
11. Optimal Design Methods: A State-Space Approach 408
Linear Quadratic Control 413
Prediction and Filtering Theory 429
Linear Quadratic Gaussian Control 436
Practical Aspects 440
Conclusions 441
Problems 441
12. Optimal Design Methods: A Polynomial Approach 447
Problem Formulation 448
Optimal Prediction 453
Minimum-Variance Control 460
Linear Quadratic Gaussian (LQG) Control 470
Practical Aspects 487
Conclusions 495
Problems 496
13. Identification 505
Mathematical Model Building 506
System Identification 506
The Principle of Least Squares 509
Recursive Computations 514
Examples 521
Summary 526
Problems 526
Appendix A. Examples 528
Appendix B. Matrices 533
Matrix Functions 533
Matrix-Inversion Lemma 536
Notes and References 536
Bibliography
Index