PERFORMANCE MODELING OF A SMART MATERIAL HYDRAULIC ACTUATOR

Smart Material Hydraulic Actuators (SMEHAs) allow high-energy-density materials, such as piezoelectrics and magnetostrictives, to be used to develop compact, high-power actuators. Hydraulic rectification using check valves converts the high-frequency, small-displacement motion of a smart material to large displacements of a hydraulic actuator. In this paper, the performance of a magnetostrictive actuator is evaluated over a range of input frequencies and loading conditions and compared to model results of the overall system. The system's dynamic performance is found to depend highly on the response of both the check valves used to rectify the motion of the smart material driver and the fluid system, including the passages connecting the smart material pump to the output hydraulic cylinder. Using AMESim, a model is developed for the response of the system and compared to experimental results.