Transmission characteristics of a two-dimensional flexure hinge mechanism

摘要

A two-dimensional flexure hinge mechanism with a novel structure is proposed to improve the transmission accuracy and efficiency of precision positioning worktables that are driven by giant magnetostrictive actuators. First, the static and dynamic mathematical models of the output displacement and input force of the flexure hinge mechanism are established on the basis of J.M. PAROS's theory of flexure hinge design. Second, the geometric size of the flexure hinge is optimised through the numerical simulation analysis method, and the optimal design parameters are obtained in accordance with the requirement of the positioning stroke of the precision positioning worktable and the output displacement of the giant magnetostrictive actuator. Third, the vibration characteristics of the flexure hinge mechanism are analysed, and natural frequencies are obtained on the basis of an established dynamic equation. Finally, the finite element, numerical analysis and experimental verification methods are adopted to verify the accuracy of the established static and dynamic models. Results show that the calculation errors of the X- and Y-direction models are 3.35% and 3.23%, respectively and the magnitude error of dynamic model is 6.7%. These results indicate that the precision of the static model is high. Modal analysis shows that the inherent frequency of the flexure hinge mechanism is 963.76 Hz and that the error of theoretical calculation is only 3.1%. These results indicate that the established dynamic model has high precision. The flexure hinge mechanism demonstrates ideal performance when the damping ratio is 0.6.