Modeling and Analysis of a Piezoelectric-film Driven Micro-positioning Stage

A flexure hinge based 3-DOF (degree of freedom) micro-positioning stage is designed, which is driven by piezoelectric-film beam. In order to accurately predict the performance of the micro-positioning stage, a theoretical modeling and analysis method is further proposed. The output model of the piezoelectric-film beam is first established on the basis of Euler-Bernouli beam theory and the piezoelectric constitutive equation under force balance conditions. Based on the compliance matrix method, the compliance model of the micro-positioning stage is then built. Accordingly, the output model of the micro-positioning stage is derived by incorporating the piezoelectric-film beam model and the mechanism compliance model. By FEA (finite-element-analysis), the displacement and rotation angle output by the micro-positioning stage are analyzed, and compared with the theoretical computation results. The comparison results show that the maximum deviations between the theoretical and simulation results are 5.4% for translation and 5.5% for rotation when only one piezoelectric-film actuator works, and the maximum deviation for output displacements is 11.6% when the three piezoelectric-film actuators work together.