Modal and Natural Frequency Sensitivity Analysis of Electrohydraulic Stewart Platform

Electrohydraulic Stewart platform is a multi-input and multi-output mechanical-hydraulic coupling system, which has the advantages of large power-to-weight ratio high accuracy. It been widely used in construction machinery, aerospace, other fields. In actual working process, especially high-speed motion, movement process will produce impact vibration then affect stability, accuracy, service life platform. When frequency external excitation coincides with natural electrohydraulic platform, it may cause failure Therefore, based on relationship between volumetric elastic modulus gas-bearing oil hydraulic stiffness leg, dynamic model was established, frequencies modal shapes were analyzed under typical conditions. The sensitivity calculation formula system upper mass outer leg given by an analytical method, influence law conditions discussed. This study can provide theoretical support for optimization