Observer-based indirect adaptive fuzzy sliding mode controller for uncertain nonlinear systems

In this paper, observer-based indirect adaptive fuzzy controller with sliding mode observer is proposed for a class of uncertain nonlinear systems. Using fuzzy logic systems to approximate the unknown nonlinear functions, which are constructed by the state variables, if they are not available, a sliding mode observer is used to estimate the state. Thus, a combination between an adaptive fuzzy control and sliding mode observer is proposed to make sure that the state estimation converges to the state variable. The stability of the whole closed-loop systems can be guaranteed by using Lyapunov stability theorem. To verify the proposed method, a simulation results are given with application on an inverted pendulum.