PERFORMANCE RECOVERY VIA A CONTROLLERS INITIAL-STATE ASSIGNMENT FOR AN OUTPUT TRACKING PROBLEM

This paper deals with the optimal output feedback problem of how to in itialize a controller's state when the initial value of the system is known. Special attention is paid to a tracking problem. Owing to the d esign freedom of the controller's initial state, there exist optimal c ontrollers to recover the optimal performance that a state feedback la w can attain. Other advantages with our optimal controllers are the re quisite internal model and an invariance property, which shows that th e assignment of a controller's dynamic parameters is independent of th e-system's initial state.