J-011

Repetitive Tracking Control of a Coarse-fine Actuator

Authors: *Gi Heung Choi; **Jong Hyun Oh, Gi Sang Choi
Affiliation: *Hansung University; **University of Seoul

Abstract
This paper discusses the repetitive tracking control method for a coarse-fine actuator which is implemented on the existing PID controller augmented with feedback linearization loop. The proposed positioning system is composed of a magnetic linear drive as a coarse actuator and a piezoelectric linear positioner as a fine actuator. In particular, nonlinear friction in a magnetic linear drive and the hysteresis characteristic of a piezoelectric linear positioner are modeled first. The feedback linearization loop uses these models in tracking position control. The control strategy is then further extended to include a repetitive control algorithm in tracking periodic inputs. The experimental results show that the performance in tracking sinusoidal waveforms is noticeably improved by augmenting a PID controller with feedback linearization loop and a repetitive controller together.

Gi Sang Choi
simpson@uos.ac.kr