document: Multivariable H/sub infinity / / mu feedback control design for high-precision wafer stage motion Conventional PID-like SISO controllers are still the most common in industry , but with performance requirements becoming tighter there is a growing need for advanced controllers . For the positioning devices in IC-manufacturing , plant interaction is a major performance-limiting factor . MIMO control can be invoked to tackle this problem . A practically feasible procedure is presented to design MIMO feedback controllers for electromechanical positioning devices , using H/sub infinity / / mu techniques . Weighting filters are proposed to straightforwardly and effectively impose performance and uncertainty specifications . Experiments show that MIMO control can considerably improve upon the performance with multiloop SISO control . Some problems are highlighted that are important for industrial practice , but lacking a workable solution
doc_bio_tags: O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O
extractive_keyphrases: weighting filters feedback
abstractive_keyphrases: ic manufacture multivariable control systems mimo systems h/sub infinity / control servo systems model uncertainty motion control mechatronics mu synthesis