Adaptive controller design for nonlinear systems with time-varying state delays

This paper focuses on the problem of adaptive tracking control for a class of multiple delays nonlinear systems in strict-feedback form. Time delays are considered to be unknown and time-varying in this system. With the help of a Backstepping design method, a state feedback controller is designed, which does not need the precise knowledge of the time delays. The proposed adaptive controller guarantees that all the closed loop signals are bounded and the system output converges to a small neighborhood of the reference signal. Simulation results are provided to show the effectiveness of the proposed approach.