Observer‐based optimal fault‐tolerant tracking control for input‐constrained interconnected nonlinear systems with mismatched disturbances

• Published in: Optimal control applications & methods Vol. 45; no. 6; pp. 2572 - 2595
• Main Authors: Liu, Shihui, Xu, Ning, Zhao, Ning, Zhang, Liang
• Format: Journal Article
• Language: English
• Published: Glasgow Wiley Subscription Services, Inc 01.11.2024
• Subjects: Actuators; adaptive dynamic programming; Adaptive systems; Algorithms; decentralized tracking control; Disturbances; Dynamic programming; Error analysis; Fault detection; Fault tolerance; input constraints; integral sliding‐mode fault‐tolerant control; interconnected nonlinear systems; Neural networks; Nonlinear control; Nonlinear systems; Optimal control; System dynamics; Tracking control; Tracking errors; Trajectory optimization
• DOI: 10.1002/oca.3173
• ISSN: 0143-2087

Summary This paper investigates an observer‐based optimal fault‐tolerant tracking control problem for interconnected nonlinear systems with input constraints and mismatched disturbances via adaptive dynamic programming (ADP). Firstly, an augmented system consisting of tracking error and the reference trajectory is constructed, and then the original optimal tracking control problem is transformed into the optimal regulation control problem of the augmented system. An integral sliding‐mode‐based optimal fault‐tolerant control scheme is developed to eliminate the effect of actuator faults and guarantee the optimal control performance. Furthermore, a neural network‐based observer is designed to identify the completely unknown system dynamics based on the input‐output data, thereby relaxing the restriction on system dynamics. Subsequently, the modified Hamilton‐Jacobi‐Bellman equations are solved by using the ADP algorithm under a critic network framework. According to the Lyapunov approach, all signals in the closed‐loop augmented system are uniformly ultimately bounded. Finally, the effectiveness of the developed control scheme is demonstrated via simulation results. This paper investigates an optimal fault‐tolerant tracking control problem for interconnected nonlinear systems with input constraints and mismatched disturbances. An observer‐based optimal fault‐tolerant control scheme is developed under a critic network framework by combining integral sliding‐mode control technique. According to the Lyapunov approach, all signals in the closed‐loop augmented system are uniformly ultimately bounded. The effectiveness of the developed control scheme is demonstrated via simulation results.