Robust output feedback control for uncertain dynamical systems with unknown time delays

This paper investigates robust output feedback controller design for a class of uncertain dynamical systems with unknown time delays. The uncertainties considered in this paper contain parametric uncertainties, unknown nonlinear functions, unknown time delays and unknown nonlinear functions. The problems of robust stabilization and robust H-infinity performance are addressed. It is shown that the solutions to the above problems can be obtained from the solutions to algebraic Riccati inequalities. A numerical example indicates that the proposed robust controller can ensure the stability of the overall system.