Variable structure adaptive fuzzy control for a class of nonlinear time delay systems

The problem of variable structure adaptive fuzzy control for a class of nonlinear time delay systems is investigated. Sliding surface dependent of the time delay is constructed based on the Lyapunov-Krasovskii method. Two adaptive fuzzy logic systems are proposed to approximate two unknown continuous nonlinear functions containing the current state and the delayed state respectively. The corresponding reaching law is designed, which can drive the state trajectory of the closed-system onto the sliding surface within limited time.