Design and investigation of ground micro-gravity experimental system for large space spinning structures

On-orbit dynamic stability of a spacecraft system with a large space structure is affected by external forces and actuator-induced perturbations. To effectively predict the on-orbit dynamic behavior of large space structures, it is urgent to validate them by ground experiments. This paper designs a novel micro-gravity experimental system for simulating the on-orbit operation state of a large space structure and conducting its ground vibration testing research. Firstly, the experimental system uses a spherical air-bearing and a gear-rotating device to achieve frictionless rotational motion of the large space structure. Secondly, two eccentric rotors are employed to simulate an actuator, serving as an on-orbit perturbation source to excite the dynamic characteristics of the large space structure. At the same time, a real-time digital image correlation (DIC) deformation measurement system captures the full-field displacement. Finally, an on-orbit dynamic experiment is conducted on the large space structure in the ground micro-gravity experimental system, and the effectiveness of the experimental system is validated through numerical simulation results.