Positioning of Three-Degrees-of-Freedom Micro-Moving Stage having Vibration-Mode Decoupling Minor Loop

摘要

We previously proposed the motional-mode decoupling control scheme for a micro--moving stage with three-degrees-of-freedom. In this control scheme, the acceleration feedback as a minor loop against the position loop was implemented and this minor loop had a role of damping. Since the displacement loop based on the motional-mode was constructed, the same loop structure was also adopted for the acceleration loop. However, there is not much meaning in the structure of motional- mode based damping loop, because the acceleration feedback is implemented to compensate for lack of mechanical damping. Then, it is preferable to adjust the damping for each vibration-mode rather than for each motional-mode. In this paper, we propose a modified decoupling control scheme in which the motional-mode is applied to the position loop and the vibration-mode is applied to the acceleration loop.