Abstract:
In order to achieve the autonomous operation of spacecraft in the Earth-Moon libration point orbits, an autonomous navigation method using space objects observations was proposed in this paper. Space objects refer to the catalogued space targets orbiting the Earth. In this method, the motion states of spacecraft can be estimated according to the angles between the spacecraft and space objects. Firstly, the constraints of star sensor field of view, earth occlusion and solar interference were analyzed, and Beidou satellites for observation are selected. Next, Fisher information matrix was adopted to analyze the observability of the system, and the optimal observation targets were selected based on the observability analysis results. Finally, spacecraft in Earth-Moon libration point orbit were selected to verify the feasibility of the proposed autonomous navigation method. The simulation results show that the positioning accuracy of the proposed method can converge to less than 1km when the simulation time are 20 hours.