부산대학교 도서관

The optimal memoryless regulator is a class of linear quadratic regulators of systems with time-delay in the states. It is constructed via a memoryless feedback, whose gain matrix is calculated with a solution of some finite dimensional Riccati equation. In this paper, a method to construct an observer is considered. It is based on the optimal memoryless regulator technique. The observer gain is obtained from a solution of a finite dimensional Riccati equation, which has a weighting parameter that tends to infinity. It is shown that the loop transfer function of the overall system of the optimal memoryless regulator and the proposed observer asymptotically approaches to that of the regulator based on the state feedback, so that the robustness which the linear quadratic regulator based on the state feedback has, of the overall system is recovered. A numerical design example is given to illustrate how the loop transfer function is recovered asymptotically.