Identification of the Dynamic Characteristics of Electro-hydrostatic Actuators

Abstract

Electro-hydrostatic actuators (EHAs) are hydraulic actuators with high power-to-weight ratios that exhibit low energy loss. However, methods for identifying characteristics and parameter have not been fully established because of a number of nonlinear factors such as static frictions of hydraulic systems. Since EHAs are driven by servo motors and hydraulic motors on the load side, the actuators are expected to experience sympathetic vibrations. We apply a feedback modulator for the purpose of the friction compensation to make identification of characteristics possible experimentally. This study proposes to apply a two-inertia model and verify the dynamic characteristics.