Combined Feedforward Control and Disturbance Rejection Control Design for a Wafer Stage: A Data-Driven Approach Based on Iterative Parameter Tuning

Mingsheng Cao, Yumeng Bo, Huibin Gao
2020 IEEE Access  
This paper presents a data-driven algorithm that combines the advantages of iterative feedforward tuning and disturbance rejection control to satisfy the precision requirements and ensure extrapolation capability of wafer scanning. The proposed algorithm differs from pre-existing algorithms in terms of its low requirement of system model, high extrapolation capability for non repetitive trajectory tracking tasks, and high tracking precision. The feedforward controller is tuned based on
more » ... tal variables. It utilizes tracking errors from past iterations to eliminate reference-induced errors without requiring a system model. Meanwhile, the system inverse is approximated during iterative process, and then a disturbance rejection control based on iterative tuning is constructed to compensate for disturbanceinduced errors. The proposed algorithm is applied to a wafer stage. The experimental results validate the effectiveness and superiority of the proposed algorithm. INDEX TERMS data-driven, disturbance rejection control, feedforward control, iterative parameter tuning, wafer stage.
doi:10.1109/access.2020.3028379 fatcat:qkp4oew4rrcefhga2oif7b65we