Adaptive fuzzy sliding mode control for the two-link robot

Abstract

This paper presents a combined fuzzy logic with the sliding mode to design a robust controller for the two-link robot system. The fuzzy sliding mode controller is used to solve the nonlinear dynamic systems, uncertainties and external disturbances. The proposed strategy uses the adaptive fuzzy system Takagi-Sugeno (T-S) to approximate the sliding function control gain and the unknown dynamics of the considered system. The projection of the parameters is used to ensure that the auxiliary gain of the sliding mode control (SMC) is small. The proposed control law is composed of two terms, a nominal one and an auxiliary term which is introduced in order to attenuate the external disturbances and to remove the fuzzy approximation modeling error. The robust stability of the closed loop system is analyzed via Lyapunov approach. The simulation results show a satisfying performance of the proposed control strategy.