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A Coarse/Fine Motion Control Stage; Preliminary Studies



H Yang, E S. Buice, T J. Fagan, Stephen J. Smith, R Hocken, D L. Trumper, Richard Seugling


We are developing a stage system, which uses a coarse/fine approach for accurate nanometer level positioning for scanning specimens over an area measuring 50 mm ? 50 mm. The completed system will comprise a short-range, 6 degree-of-freedom fine-motion platform (10 mm, 40 microradians) carried by a long-range, two-axis X-Y coarse positioning system, to achieve nanometer resolution positioning. Motion of the platform relative to a measurement frame will be measured using a heterodyne laser interferometer. The complete system will be housed in a vacuum system, pumped to better than 10-3 Torr, and operated in a temperature-controlled laboratory. Prior to manufacture of this complete system, a number of conerns such as, vacuum system design, nanometer precision bearings, controller strategy and interferometer configuration must be addressed. Currently, we are developing controller algorithms and implementation strategies. As a first step to assess a cascaded controller, a considerably simpler, single-axis, coarse/fine stage has been design and manufactured. This system will be interfaced with a custom-built, DSP-based controller based around a dSPACE TM architecture described herein. As well as some controller implementation strategies and considerations, results from preliminary tests on this system will be presented.
Conference Dates
October 24-29, 2004
Conference Location
Orlando, FL, USA
Conference Title
ASPE 19th Annual Meeting


cascaded control, laser interferometry, nanometer resolution, precision motion


Yang, H. , Buice, E. , Fagan, T. , Smith, S. , Hocken, R. , Trumper, D. and Seugling, R. (2004), A Coarse/Fine Motion Control Stage; Preliminary Studies, ASPE 19th Annual Meeting, Orlando, FL, USA (Accessed November 30, 2023)
Created September 30, 2004, Updated October 12, 2021