Identification and control of precision XY stages with active vibration suppression system

In this paper, a design method of the reaction force control system for ultra-precision stage which equips vibration control system, is proposed. Taking the application to semiconductor manufacturing into consideration, the designed system deals with both the reaction force due to the stage movement and the vibration from the external environment. The experimental setup for a 6-degree of freedom (DOF) motion control system is firstly designed. The system is controlled by two counter weights that are placed eccentric from the center of gravity, i.e. two weights are not co-axial. Next, the system identification experiments based on a subspace method are performed to build the multi-input multi-output state-space model. The reaction force and vibration control systems are designed using the identified model based on bilateral control strategies. The main advantages of the proposed identification and control approach are that the experimental time for accurate identification is quite short and the control system can be systematically designed. Finally, the effectiveness of the proposed control system is verified through the vibration control experiments.