TY - BOOK AU - Astrom,Karl J. AU - Witternmark,Bjorn TI - Computer-controlled systems : : theory and design / T2 - Prentice-Hall Information And Systems Sciences Series SN - 0133148998 PY - 1997/// CY - Englewood Cliffs, New Jersey PB - Prentice Hall KW - SISTEMAS DE CONTROL KW - CONTROL SYSTEMS N1 - 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 ER -