Observer-Based Adaptive Fuzzy Sliding Mode Control for Switched Uncertain Nonlinear Systems with Dead-Zone Input

This paper considers the problem of observer-based adaptive fuzzy sliding mode control for switched uncertain nonlinear systems with dead-zone input in strict-feedback form. The explored switched systems include unknown nonlinearities, dead-zone and immeasurable states. Fuzzy logic systems are used to approximate unknown nonlinear functions of the dynamic system and unknown upper bounds of uncertainties, respectively. A state observer based on state variable filters is developed to estimate the immeasurable states. Adaptive technique and sliding mode control method are utilized to construct a controller. By choosing an appropriate Lyapunov function, the proposed controller is designed to demonstrate that all the signals in the closed-loop system can not only guarantee uniformly ultimately bounded, but also achieve good tracking performance. Finally, the simulation results are provided to demonstrate the effectiveness of the proposed approach.