Robust output tracking control of nonlinear systems against actuator faults

The problem of robust output tracking of nonlinear systems is considered in this paper. The systems under consideration are subjected to actuator faults. The main difficulty in system design is that not only the fault information but also the function of the system model are unknown. Based on the universal approximation property of fuzzy system, a novel control scheme is proposed to guarantee the stability and desired output tracking performance of the closed-loop system, though there are unknown nonlinearities and actuator faults. Different from existing works, the fuzzy systems used to approximate the unknown functions are nonlinearly parameterized, which removes the restriction that the fuzzy basis functions must be well known before control design. The effectiveness of the proposed control scheme is verified by a simulation example.