Direct adaptive fuzzy control for a class of nonlinear discrete-time systems with time-varying dead-zone

A direct adaptive fuzzy control scheme is developed for a class of nonlinear discrete-time systems. In this scheme, the fuzzy logic system is used to design controller directly, and the parameters are adjusted by time-varying dead-zone, which its size is adjusted adaptively with the estimated bounds on the approximation error. The proposed design scheme guarantees that all the signals in the resulting closed-loop system are bounded, and the tracking error converges to a small neighborhood of the origin. Simulation results indicate the effectiveness of this scheme.