Abstract: A design approach to the adaptive output feedback controller is proposed for a class of parametric nonlinear time-delay systems by means of time-delay filters and the backstepping technique. The requirement for the nonlinear time-delay terms of the systems is relaxed. The global asymptotical tracking of given trajectories is achieved and the boundedness of all signals of the resulting closed-loop system is also guaranteed. Based on the method of the Lyapunov-Krasoviskii functional, the stability of the closed-loop system is proved. The feasibility of the proposed approach is illustrated by a simulation exampled.

Key words: nonlinear time-delay systems, adaptive control, Lyapunov-Krasoviskii functionals, backstepping