Observer-based sliding mode control for a class of nonlinear time-delayed systems

The sliding mode control scheme is proposed for a class of nonlinear time-delayed systems by using a novel disturbance observer. The lumped nonlinear disturbances are first estimated by using the current system states. Then the disturbance observe-based sliding mode controller is designed to guarantee the asymptotical stability of the closed-loop system. The prominent advantage of the proposed scheme is that the linear boundary condition for the uncertainties are removed, thus largely reducing the switching gain. The simulation results illustrate the obtained results.