Adaptive fault‐tolerant robust control for a linear system with adaptive fault identification

Abstract

An integrated design of the adaptive robust control and the fault identification for a linear system with actuator faults is proposed. When actuators suffer from unpredicted faults, the proposed control strategy can track the actuator fault parameters adaptively without any prior fault information, and guarantee the robustness of the faulty system. An unknown input observer is designed to decouple the disturbance and the actuator faults. Then an adaptive control law with projection is presented to track the fault parameters. A new definition of robust H ∞ -like performance is proposed to ensure that the system is robust for both exogenous disturbance and unpredicted faults. Then the adaptive robust control law is designed to guarantee the system satisfying the robust H ∞ -like performance. Finally, the effectiveness of this control strategy is illustrated through the faulttolerant longitudinal control of the simplified F-18 aircraft model.

An adaptive fault-tolerant robust controller with fault diagnosis for submarine’s vertical movement

“…Fig. 7 shows the results of the fault parameter θ(t) being tracked by the fault parameter tracking law (14). Fig.…”

“…According to the theorem proposed by Shen Yi [14], system (8) is asymptotically stable when ( ) 0, t = W and system (8) satisfies the robust H∞-like performance index, that is…”

Output‐feedback sliding‐mode control for systems subjected to actuator and internal dynamics failures

“…In extreme operational conditions, they may cause loss of performance or even damages, justifying a high demand on effective fault-tolerant control (FTC) schemes [1]. Active FTC relies on fault detection and isolation (FDI) [2][3][4][5][6][7][8][9] to redesign the control law such that the faulty system reaches an acceptable performance. On the other hand, passive FTC uses robust or adaptive control techniques to maintain the performance of the closed-loop system insensitive to certain faults [10].…”

Fault diagnosis and robust fault-tolerant control for linear over-actuated systems

“…So far, a number of fault estimation approaches have been proposed in the literature. For instance, adaptive observer has been used for fault estimation in Wang and Daley, 4 Jiang et al, 5 Liu et al, 6 and Shen et al 7 A fault isolation filter with fault estimation ability is proposed in Keller 8 and this method has been further extended and applied to three-tank system 9 and winding machine. 10 It is known that the faults can be classified into additive faults and multiplicative faults according to the manner of influence.…”