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Active vibration control using a novel three-DOF precision micro-stage

In this paper, we present an active vibration control system which is constructed based on a novel three-degrees-of-freedom (DOF) precision micro-stage. Unlike the traditional tripod systems, the proposed micro-stage is established to guarantee the compactness (60 mm(h) × 160 mm(d)) and the simplicity of its structure as well as the appropriate vertical/horizontal stiffness and the repeatability, which are essential in achieving the accuracy of sub-micrometers. First, combined with a finite element method (FEM), a physical model for the proposed micro-stage is constructed and its physical parameters, such as stiffness and damping coefficients, are estimated to predict the experimental results with high fidelity. In order to overcome the dynamic variations naturally stemming from the payload as well as the parameter uncertainties, a robust control system is then proposed to efficiently mitigate the vibration with a scale of sub-micrometers. Compared to the conventional control strategy, the proposed robust control scheme successfully establishes the active vibration control system and its performance is examined and validated through extensive experiments.