On-Line Parameter Estimation

Abstract

In this chapter, we focus on the design of on-line parameter estimators or adaptive laws. An adaptive control scheme has two essential ingredients: (i) a control structure that could be used to meet the control objective if the plant parameters are known; and (ii) a parameter estimator or adaptive law which provides estimates of the plant or controller parameters, to be used when the plant parameters and hence the controller parameters are unknown. The properties of both the control structure and the adaptive law play a crucial role in determining the stability of the closed loop adaptive system. Having already studied some of the control structures of interest to us in the last chapter, we now concentrate on the adaptive laws.