Robust Composite Adaptive Fuzzy Identification Control of Uncertain MIMO Nonlinear Systems in the Presence of Input Saturation

Adaptive fuzzy control methods are very interesting because of their robustness against uncertainties. In this paper, a robust composite adaptive fuzzy controller for a class of MIMO nonlinear systems in the presence of input saturation is presented. Using the modeling error between the plant states and a serial-parallel identification model, an adaptive fuzzy system is employed to approximate the unknown uncertainties of the system and in addition, each subsystem of MIMO system is able to adaptively estimate and compensate uncertainties and disturbances with unknown bounds. A robust control term is designed to remove the influence of fuzzy approximation errors. Stability of the proposed method is guaranteed based on Lyapunov theory. Finally, in our simulation studies, to demonstrate the usefulness and effectiveness of the proposed technique, a two-link robot manipulator is employed.