Variable structure adaptive control for a class of continuous time-delay systems

This paper focuses on the design of variable structure adaptive control laws for a class of uncertain time-delay systems with time-varying delays. The uncertainties considered here are parametric and norm bounded. Two main problems are investigated. In the first problem, robust adaptive control results are developed. In the second problem, a robust redesign approach is developed yielding an adaptive-based controller against controller gain perturbations. The objective is to derive tractable synthesis conditions for the variable structure adaptive control laws. Simulation results are obtained through a numerical example.