A Parallel Compliant x-y-θ Micro-stage with the Characteristic of High Displacement Magnification

Microassembly and micromanipulation tasks require micro-stages with high displacement magnification ratios, multiple degrees of freedom and low output coupling ratio. To solve this problem, a parallel x-y-θ micro-stage is designed in combination of compliant amplification mechanisms and composite parallelogram mechanisms. Based on the pseudo-rigid-body method, statics and dynamics models of the micro-stage are firstly derived. Then, the output displacement, the rotation angle, the resonant frequency and the output coupling ratio of the micro-stage are analyzed through finite-element simulations. Finally, an experimental system is established to verify its open-loop performances. Experimental results demonstrate that x- and y-direction displacement magnification ratios of the micro-stage are 8.1 and 8.3, respectively. The workspace range is 162.2 μm×165.6 μm×2547.1 μrad if the input displacement is 20 μm, and the first resonant frequencies in x and y translational motions are 224.6 Hz and 227.7 Hz. Meanwhile, output coupling ratios of x-axis and y-axis translational motions are 0.86% and 0.91%, respectively. Experimental results and finite-element simulations are also compared, and the relative errors of the amplification ratio and the first resonant frequency are lower than 27.2% and 6.4%. Therefore, experimental tests validate the effectiveness of theoretical models and finite-element simulations.