An improved stability analysis and design of fuzzy control systems

This paper presents the stability analysis and design of fuzzy control systems. An improved and simple stability condition will be derived based on the Lyapunov´s stability theory. The derived stability condition involves a smaller number of Lyapunov´s conditions than that given by Wang et al. (1996). A design of the membership functions of the fuzzy controller will be given. In our approach, the number of rules of the fuzzy controller can be different from that of the fuzzy plant model. Our approach can be applied to those fuzzy controllers with both positive and negative grades of membership, An application example on stabilizing a mass-spring-damper system will be given to show the stabilizability of the fuzzy controller.