Design and Implementation of High Dynamics Servo-Valve Driver for Electro-hydraulic Actuator in Legged Robot’s Applications

摘要

Electro-Hydraulic Actuator (EHA) is widely used in many applications, such as humanoid robotics, rehabilitation devices, prosthetics, aeronautics, and industrial actuators. In robotics and legged robots development, high dynamics and wide bandwidth are major issues. The electro-hydraulic servo-valve (EHSV) plays a vital role in controlling electrohydraulic actuators due to the high bandwidth as a main advantage compared to the conventional electro-hydraulic proportional valves. To take advantage of this criteria, the components of the driving system should be well designed in respect of the desired dynamic behavior. Certain EHSVs have unique electrical characteristics that make them difficult to drive. This paper presents a new topology electronic driver to enhance the dynamic characteristics of the EHSV-based actuation system. A theoretical study has been conducted for the driver, and the design is well verified using the Simscape tool (hydraulics, electrical and mechanical) in Simulink MATLAB. Finally, experimental results are obtained on a laboratory hydraulic system test bench.