Robust control of uncertain time-delay systems - A minimax optimal approach

This paper considers a problem of robust controller design for a class of uncertain time-delay systems. The uncertainty is assumed to satisfy a certain integral quadratic constraint. This description of uncertainty allows for time-delays to be considered as uncertainty as well. The state feedback controller is a minimax optimal controller in the sense that it minimizes the maximum value of a corresponding linear quadratic cost function over all admissible uncertainties. The controller absolutely stabilizes the closed loop uncertain system and is constructed by solving a finite dimensional parameter dependent algebraic Riccati equation.