Closed Loop Identification of a DC Servomechanism

Abstract

A new method for closed loop identification of position controlled DC servomechanisms is proposed. The loop around the servo is closed using a proportional derivative (PD) controller. A model of the servo is simultaneously controlled using a second PD controller. The error and its time derivative between the output of both, the real servo and its model, is employed for identifying the motor parameters which in turn are employed for updating the model. Properties of the identification scheme are studied using Lyapunov stability theory. Experimental results on a laboratory prototype are shown to validate the proposed approach