Control of ultra precision hybrid stage

In this paper, we presented an ultra precision hybrid stage designed to move and align an object on it for measurement of its 2-dimensional image. The hybrid stage is composed of two individually operating xy0-stages, called by coarse and fine stages. The coarse stage is driven by the three linear motors and produces the initial movement of an object. On the other hand, the fine stage is driven by the four voice coil motors and provides the final alignment of it with sub-micron meter accuracy. For control of the hybrid stage, we designed a position and velocity controller and a reaction force compensator, and evaluated the performance of the designed controller and reaction force compensator by experiments.