Integrated robust tracking controller design for a developed precision planar motor with equivalent disturbances

摘要

This study studies the precision motion control of a developed planar motor motion system under the existence of external disturbance, non-linearity, uncertainty, and crosstalk coupling problems those inevitably deteriorate the achievable control object and even make the system unstable. To address these issues, an integrated robust tracking controller consists of feedforward (FF), proportional–integral-derivative (PID), and robust compensator (RC), is developed for the planar motor stage to practically achieve high control performance. Specifically, the FF term is designed based on the stage dynamics model to reduce the tracking error, and the PID term is synthesised by pole assignment to stabilise the nominal model. More importantly, RC is particularly designed to suppress the effects of equivalent lumped disturbances including the external disturbances, uncertainties, non-linearities, and crosstalk couplings. The proposed integrated controller possesses robust stability under the uncertain disturbances, and facilitates parameter tuning which is meaningful for practical implementation. Finally, comparative experiments are conducted on a developed planar motor of wafer stage, and the results validate the practical effectiveness and high-performance nature of the proposed control strategy.