Observer-Based Adaptive Fuzzy Fault-Tolerant Optimal Control for SISO Nonlinear Systems

• Published in: IEEE transactions on cybernetics Vol. 49; no. 2; pp. 649 - 661
• Main Authors: Li, Yongming, Sun, Kangkang, Tong, Shaocheng
• Format: Journal Article
• Language: English
• Published: United States IEEE 01.02.2019; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Actuators; Adaptive control; Adaptive filters; Adaptive fuzzy fault-tolerant control; adaptive optimal control; Adaptive systems; backstepping technique; Control stability; Fault tolerance; Fault tolerant systems; Fuzzy control; Fuzzy logic; Fuzzy systems; Nonlinear control; Nonlinear systems; Optimal control; Output feedback; SISO (control systems); State observers; uncertain nonlinear systems
• ISSN: 2168-2267; 2168-2275; 2168-2275
• DOI: 10.1109/TCYB.2017.2785801

This paper investigates adaptive fuzzy output feedback fault-tolerant optimal control problem for a class of single-input and single-output nonlinear systems in strict feedback form. The considered nonlinear systems contain unknown nonaffine nonlinear faults and unmeasured states. Fuzzy logic systems are used to approximate cost function and unknown nonlinear functions, respectively. It is assumed that the states of the systems to be controlled are unmeasurable, thus an adaptive state observer is developed. To solve the nonaffine nonlinear fault control design problem, filtered signals are introduced into the adaptive backstepping control design procedures, and in the framework of adaptive critic technique and fault-tolerant control technique, a novel adaptive fuzzy fault-tolerant optimal control scheme is developed. The stability of the closed-loop system is proved by using Lyapunov stability theory. The simulation results verify the effectiveness of the proposed control strategy.