Fuzzy sliding mode control for nonlinear systems

A new fuzzy sliding mode control based on the design of time-varied sliding surface and the fuzzy logic system is developed for a kind of uncertain nonlinear systems. The main characteristics of the proposed fuzzy sliding mode control are as follows. The first is that it does not assume that the functions in the systems are known; rather it uses fuzzy logic systems to approximate them. The second is that the trajectories of the system remain in the time-varied sliding surface from the beginning of any initial states; therefore, it is robust to the parameter variation and disturbance. It is proved that the proposed fuzzy sliding mode control can guarantee the stability of the closed-loop system.