Adaptive variable structure control for chaos suppression of unified chaotic systems

This paper investigates the chaos suppression problem for a class of unified chaotic systems subject to uncertainties and control input with dead-zone nonlinearity. Using the variable structure control technique, a robust adaptive control law is established to suppress chaos in a class of unified chaotic systems even with unknown uncertainties and dead-zone nonlinearity in input. In particular, a switching surface is newly proposed to simplify the task of ensuring the stability of the closed-loop system in the sliding mode. Numerical results validate the effectiveness of the proposed adaptive control scheme.