Guidance and control method of levitation experiment facility inside China’s Space Station

To optimize the microgravity level of the levitation experiment facility (LEF) inside China’s Space Station (CSS), the limited intra-vehicular travel distance and various uncertainties were considered, so as to achieve the optimal microgravity level under different time scales. An autonomous trajectory planning method based on convex optimization and a trajectory tracking scheme based on error feedback control were proposed. Firstly, the structure of the LEF was introduced, and a spatial relative motion model was provided and linearized. Secondly, the motion trajectory and corresponding controlling force sequence with the optimal microgravity level were solved by convex optimization. Finally, the proportion-integration-differentiation (PID) tracking control law based on error feedback was designed to realize the fast tracking control of the optimized trajectory while guaranteeing the microgravity level. Numerical simulation results show that the optimal microgravity level can be $ 9.121 \times {10^{ - 6}}\; {\mathrm{m}}/{{\mathrm{s}}^2} $ when the microgravity science experiment lasts for one hour. The autonomous trajectory planning method based on convex optimization and the trajectory tracking scheme based on error feedback control can achieve the optimal microgravity level for the specified duration. It provides a new solution to the current problem of the optimal microgravity level for a medium duration (such as one hour) and enhances the application value of the LEF in the CSS.