Fuzzy Observer Based Constraint Control for Switched Systems With Actuator Failures and Partially Unstable Subsystems

Abstract

This paper investigates the adaptive fuzzy observer-based tracking control problem for switched nonlinear systems with full state constraints and actuator failures under the switching law with average dwell time. Since the states in the system are not measurable, a nonlinear fuzzy observer is designed to estimate the immeasurable states. At the same time, the Tangent Barrier-Lyapunov functions are selected to solve the full-state constraint problem. In addition, because of the existence of unknown parameter in actuator failures, the adaptive approach is used. Further, owing to actuator failures in controller, which may lead to some subsystems to be unstable, the switching law under average dwell time is adopted. Thus, even if there exist the actuator failures and partially unstable subsystems, the proposed method can guarantee that all signals in the closed-loop system are bounded, the system output can track the desired signal, and all system states satisfy their corresponding constrained conditions. Moreover, the observer states can well estimate the immeasurable states. Finally, the effectiveness of the presented control scheme is verified by a simulation example.