Single axis, long-stroke precision motion stages, with large dynamic range have been studied in a number of previous works. The design and control of a dual voice coil linear nano-positioner (Fig. 1) was presented before by the authors. Natural frequencies and mode shapes were estimated based on the geometry of the system and the catalogue values for stiffness of air bearings. In this study, impact testing is applied to the nano-positioner to experimentally obtain the vibratory dynamics. Positioning control results were formerly presented where the holding resolution could be brought down to the sensor noise floor of +/-5 [nm], however, errors in the order of 25 - 50 [nm] were present during constant feed motion. In this study, Heydemann's formulation is used to compensate for the quadrature detection errors of the position sensor, which are found to be the major constituent of positioning errors during constant feed.
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