Design of Tracking Suspension Gravity Compensation System for Satellite Antenna Deployable Manipulator

A relatively real zero gravity ground simulation environment is created to test the deployment characteristics of the deployable manipulator of satellite antenna. A tracking suspension gravity compensation system of the satellite antenna is designed. Firstly, a three-axis tracking suspension manipulator is designed with the same structure as the antenna deployable manipulator, to track the position of deployable manipulator of satellite antenna. The under-load position accuracy is analyzed by the finite element method. Then, a force tracking controller of the manipulator is designed according to the admittance control method, and a PD (proportional-differential) force control strategy based on position inner loop is adopted to design the tension control algorithm of the tension system to the sling. Finally, the position tracking performances of the joints of the tracking suspension manipulator to the corresponding joints of the antenna deployable manipulator in orbit operation mode are verified by experiments, as well as the precision of gravity compensation. Experimental results show that the tracking error of each axis is less than ±0.03°. During the stable operation, the tension control deviation of the sling is within 1.2% F.S. (full scale). High-precision position tracking and gravity compensation are achieved during the unfolding process of the antenna deployable manipulator, which meets the requirements of antenna deployment test.