Research Status and Development Trend of Electro-hydrostatic Actuators for Robots

doi:10.3901/JME.2025.04.273

Abstract

Abstract: Hydraulic actuated robots are widely used in many scenarios due to their advantages of high payload and strong anti-interference ability. The actuators serve as the muscle of the robot to output force directly, which are significant for the performance of the robot. Among kinds of actuators, electro-hydrostatic actuators(EHA) have the advantages of high integration, high energy efficiency, and high-power density, and have been widely used in robotics, aerospace, engineering equipment, and other fields. The development status of EHA for robots is reviewed from five aspects: robot application, system configuration, hardware composition, control algorithm and development trend of EHA. Firstly, the applications of EHA in articulated robots, wearable robots, legged robots and other fields are introduced, and the system configurations are introduced in terms of fast response and energy. Then, the hardware compositions of EHA are discussed, including motors, hydraulic pumps, actuators and integrated valve blocks and other core components. In addition, this study summarizes the control algorithm of EHA for the control requirements of the hydraulic robots. Finally, the future trends of EHA for robots from the perspectives of components, drive, control and energy saving are presented.

Key words: electro-hydrostatic actuator, hydraulic-actuated robot, system configuration, integrated design, precise control

CLC Number:

TH137
TH322

ZHANG Junhui, NI Xiaohao, ZONG Huaizhi, GUO Yitao, YANG Meisheng, ZHU Qixin, XU Bing. Research Status and Development Trend of Electro-hydrostatic Actuators for Robots[J]. Journal of Mechanical Engineering, 2025, 61(4): 273-289.

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