Co-Design Approaches for Dependable Networked Control Systems

Title Page......Page 3
Copyright
......Page 4
Contents......Page 5
Foreword
......Page 12
Introduction and Problem Statement......Page 14
I.1. Networked control systems and control design challenges
......Page 15
I.2. Control design: from continuous time to networked implementation
......Page 17
I.3.Timing parameter assignment
......Page 19
I.4. Control and task/message scheduling
......Page 21
I.5. Diagnosis and fault tolerance in NCS
......Page 23
I.6. Co-design approaches
......Page 24
I.7. Outline of the book
......Page 25
I.8. Bibliography
......Page 28
1.1. Overview......Page 32
1.2. Preliminary notions on real-time scheduling......Page 33
1.2.1. Some basic results on classic task model scheduling......Page 34
1.2.1.1. Fixed priority scheduling......Page 35
1.2.1.3. Discussion......Page 36
1.2.2. m,k-firm model......Page 37
1.3. Control aware computing......Page 39
1.3.1. Off-line approaches......Page 40
1.3.2. Quality of Service and flexible scheduling......Page 41
1.4. Feedback-scheduling basics......Page 43
1.4.1.2. Sensors and actuators......Page 45
1.4.1.3. Control design and implementation......Page 46
1.4.2.1. Feedback scheduling a web server......Page 48
1.4.2.2. Optimal control-based feedback scheduling......Page 49
1.4.2.3. Feasibility: feedback-scheduler implementation for robot control......Page 52
1.5. Fault diagnosis of NCS with network-induced effects......Page 56
1.5.1.1. Low-pass post-filtering......Page 57
1.5.1.2. Structure matrix of network-induced time delay......Page 59
1.5.1.3. Robust deadbeat fault filter......Page 60
1.5.1.4. Other work......Page 62
1.5.2.2. Stochastic packet losses......Page 63
1.5.3. Fault diagnosis of NCS with limited communication
......Page 64
1.5.4. Fault-tolerant control of NCS
......Page 65
1.7. Bibliography......Page 66
2.1. Overview......Page 75
2.2.1. Introduction
......Page 77
2.2.2.1. Initial conditions......Page 79
2.2.2.2. Infinite dimensional systems......Page 80
2.2.3. Delay models
......Page 82
2.2.4.1. The second method......Page 83
2.2.4.2. The Lyapunov?Razumikhin approach......Page 84
2.2.4.3. The Lyapunov?Krasovskii approach......Page 85
2.2.5. Summary: time-delay systems and networking
......Page 87
2.3. Weakly hard constraints......Page 88
2.3.1. Problem definition
......Page 89
2.3.3. Design of accelerable controllers
......Page 91
2.3.4. Accelerable LQR design for LTI systems
......Page 92
2.3.5. Kalman filtering and accelerability
......Page 94
2.3.6 Robustifying feedback scheduling using weakly hard scheduling concepts
......Page 95
2.3.7. Application to the attitude control of a quadrotor
......Page 97
2.4. LPV adaptive variable sampling......Page 101
2.4.1. A polytopic discrete-plant model
......Page 102
2.4.2. Performance specification
......Page 104
2.4.3. LPV/H∞ control design......Page 105
2.4.4. Experimental assessment
......Page 106
2.5. Summary......Page 110
2.6. Bibliography......Page 111
3.1. Overview......Page 116
3.2.1.1. The considered process control application......Page 118
3.2.1.3. The implementation through a network......Page 119
3.2.1.4. Evaluation of the influence of the network on the behavior of the process control application
......Page 121
3.2.1.5. Idea of hybrid priority schemes: general considerations......Page 122
3.2.2.1. hp scheme......Page 125
3.2.2.2. hp+sts scheme......Page 126
3.2.2.3. hp+dts scheme......Page 127
3.2.3.1. Study conditions......Page 130
3.2.3.2. hp scheme......Page 131
3.2.3.3. hp+sts scheme......Page 136
3.2.4. QoC visualization
......Page 139
3.2.5. Comment
......Page 140
3.3. Bandwidth allocation control for switched Ethernet networks......Page 143
3.3.2.1. Introduction......Page 145
3.3.2.2. Network modeling......Page 146
3.3.2.3. System modeling......Page 149
3.3.2.4. Controller modeling......Page 150
3.3.4.1. Maximum delay computation......Page 152
3.3.4.2. Results......Page 153
3.4. Conclusion......Page 155
3.5. Bibliography......Page 156
4.1. Overview......Page 159
4.2. Adaptive scheduling and varying sampling robust control......Page 161
4.2.1. Extended elastic tasks controller......Page 162
4.2.2. Case study......Page 163
4.3. MPC-based integrated control and scheduling......Page 166
4.3.1. Resource constrained systems......Page 167
4.3.2. Optimal integrated control and scheduling of resource constrained systems......Page 170
4.4.1. Problem formulation
......Page 172
4.4.2.1. Cost function definition......Page 174
4.4.2.2. Introductory example: quadrotor attitude control......Page 175
4.4.3.1. Problem formulation......Page 176
4.4.3.3. Feedback-scheduling algorithm deployment......Page 177
4.4.4. Application to the attitude control of a quadrotor......Page 178
4.5. Control and real-time scheduling co-design via a LPV approach......Page 180
4.5.1. A LPV feedback scheduler sensible to the plant’s closed-loop performances......Page 181
4.5.2.1. Performance evaluation of the control tasks in view of optimal resource distribution......Page 184
4.5.2.2. Simulation with TrueTime......Page 185
4.6. Summary......Page 187
4.7. Bibliography......Page 191
5.1. Introduction......Page 194
5.1.1. System architecture......Page 195
5.2. Scheduling under m, k -firm constraint
......Page 197
5.2.2. Static scheduling policy under m,k-firm constraints and schedulability issue......Page 198
5.2.3. Static scheduling under m, k - constraints and mechanical words
......Page 199
5.2.4. Sufficient condition for schedulability assessment under m,k-pattern defined by a mechanical word......Page 200
5.2.5. Systematic dropping policy in control applications......Page 201
5.3.1. Generic model......Page 202
5.3.2. Example of multidimensional system......Page 203
5.3.3. Stability condition......Page 204
5.4. Optimized control and scheduling co-design......Page 206
5.4.1. Optimal control and individual cost function......Page 207
5.4.2. Global optimization......Page 209
5.4.3. Case study......Page 210
5.4.3.3. Optimal controller......Page 212
5.4.3.5. Simulation results for hard real-time constraints......Page 213
5.4.3.6. Simulation results for m, k-firm constraints......Page 214
5.5. Plant-state-triggered control and scheduling adaptation and optimization......Page 218
5.5.2. On-line plant state detection......Page 219
5.5.3. Global optimization of control tasks taking into account the plant state......Page 220
5.5.4. Case study......Page 222
5.5.4.1. Simulation scenario......Page 223
5.5.4.2. Observed performance......Page 226
5.6. Conclusions......Page 227
5.7. Bibliography......Page 229
6.1. Introduction......Page 231
6.2.1. Introduction to diagnosis......Page 232
6.2.2. Quantitative model-based residuals......Page 234
6.2.2.1. Parity relations......Page 236
6.2.2.2. Observers bank......Page 237
6.2.3.1. The system-residual generation......Page 239
6.2.3.2. Observer-based residuals......Page 241
6.2.4. Diagnostic summary......Page 243
6.2.5. Introduction to FTC......Page 244
6.3. Networked-induced effects......Page 246
6.3.1. Example of network-induced drawbacks......Page 247
6.3.2. Modeling data dropouts......Page 248
6.3.3. Modeling network delays......Page 250
6.4. Pragmatic solutions......Page 251
6.4.1.1. Clock synchronization......Page 252
6.4.1.2. Data reconstruction......Page 253
6.4.1.3. Example......Page 254
6.4.2. Data loss and diagnostic blocking......Page 255
6.5.1. Residual generation with transmission delay
......Page 256
6.5.2. Adaptive thresholding......Page 257
6.5.2.1. Optimization-based approach for threshold selection......Page 258
6.5.2.2. Network calculus-based thresholding......Page 259
6.5.3. Fault isolation filter design in the presence of packet dropouts......Page 264
6.5.4.1. Problem formulation......Page 267
6.5.4.2. Kalman filter with partial data loss......Page 268
6.7. Bibliography......Page 270
7.1. Introduction......Page 275
7.2.1. The system......Page 277
7.2.2.1. Introduction to quaternions......Page 278
7.2.2.2. The quadrotor model......Page 279
7.2.2.3. The inertial measurement unit IMU model......Page 281
7.2.3.2. Linear quadratic control......Page 282
7.2.4.1. Nonlinear observer......Page 284
7.2.4.2. Extended Kalman filter......Page 285
7.2.5.1. Sensor diagnosis......Page 287
7.3.1. Architecture of the networked control system
......Page 290
7.3.2. Network design......Page 292
7.4. Hardware in the loop architecture......Page 293
7.4.1. The ORCCAD approach......Page 294
7.4.2. Quadrotor simulation setup......Page 296
7.5.1. Basic attitude control
......Page 298
7.5.2.1. Pragmatic solution......Page 299
7.5.2.2. m, k-firm solutions......Page 300
7.5.2.3. Dynamic priorities......Page 303
7.5.2.4. Extended Kalman filter......Page 305
7.5.3.1. Basic scenario......Page 306
7.5.3.3. Sensor failure......Page 307
7.6. Summary......Page 310
7.7. Bibliography......Page 311
Glossary and Acronyms......Page 313
List of Authors......Page 316
Index......Page 319