Research on gravity compensation technology for extravehicular activity training facility

Abstract

Objective: To improve the current extravehicular activity facility, new gravity compensation technology is researched. Methods: To assure the rapidity and precision of gravity compensation, high torque motor and low torque motor cooperation are applied to generate contragravity; to offload the maximum added mass, the system tracks the target position actively by servo control; to meet astronaut specific needs of extravehicular activity, the ingenious lift spreader of suspension system is designed. Results: Design analysis and model verification show that the position track error is less than 10 mm and the accuracy of the single suspended cable tension force is 99.5 % at the maximum limit of 0.1 m/s velocity and 0.1 m/s2 acceleration. Conclusion: The facility that applied new gravity compensation technology is able to generate near-zero microgravity environment, which is more suitable for training of extravehicular activity.