Robust Adaptive Fuzzy Sliding Mode Control for a Class of Uncertain Discrete-time Nonlinear Systems

This paper presents an adaptive interval type-2 fuzzy sliding mode controller for a class of unknown nonlinear discrete-time systems with training data corrupted by noise or rule uncertainties involving external disturbances. Adaptive interval type-2 fuzzy control scheme and sliding mode control (SMC) approach are incorporated to implement the main objective of controlling the plant to track a reference trajectory and prevent big chattering of the control effort. The Laypunov stability theorem has been used to testify the asymptotic stability of the whole system and the free parameters of the adaptive fuzzy controller can be tuned on-line by an output feedback control law and adaptive laws. The overall adaptive scheme guarantees the global stability of the resulting closed-loop system in the sense that all signals involved are uniformly bounded. The simulation example is given to confirm validity and tracking performance of the advocated design methodology.