Robust adaptive sliding-mode control for continuous time-delay systems

This paper focuses on the development of a robust adaptive sliding-mode scheme for the control of a class of uncertain time-delay systems with time-varying delays. The uncertainties are parametric and norm-bounded. Two main problems are investigated. In the first problem, a sliding-mode observer-based output feedback control scheme is developed. In the second problem, a robust redesign approach is developed yielding an adaptive-based controller against controller and sliding-mode observer gain perturbations. The objective is to derive stability conditions for the closed-loop system in the presence of gain perturbations. Simulation results are obtained through a numerical example.