Adaptive robust stabilization of a class of time-delay uncertain systems

The robust stabilization of a class of time-delay uncertain systems with unmatched perturbations is investigated in this paper. When the perturbations are bounded but the values of the upper bounds are unknown, a sufficient condition is given to obtain a delay-independent adaptive robust controller such that the systems are robust stable. Adaptive laws are given to estimate the upper bounds of the uncertainties, and robust controllers are designed based on the estimated values. The robust stability of the closed-loop systems is achieved in the means of uniform ultimate boundedness.