Obervability Analysis for Space Target Sequential-Image Relative Navigation System with Fully-Actuated System Control

Space target sequential-image relative navigation system is an important part of the rendezvous and docking mission. Due to the poor observability of the system, the control input is necessary to obtain the target motion state. The rendezvous and docking mission also requires the control input to make the spacecraft approach the target. The fully-actuated system theory is an effective way to obtain the optimal control. To obtain better relative navigation accuracy and provide more accurate target state to the control system, the relative navigation system observability is analyzed based on the optimal control. Besides, the linear quadratic indicator for the control is also improved combined with the observability criteria. The optimal control input is also solved through the new performance indicator. The simulation results show that the new indicator can improve the relative navigation accuracy to some degree, which will provide a new though to improve the navigation and guidance scheme of the rendezvous and docking mission.