Multi-Information Assisted Optical Navigation Method for Mars Aerobraking

The Mars landing and sampling return missions are restricted by the key factor of fuel. The use of Mars aerobraking for orbital descent is an important means to save fuel. During the process of aerobraking, the spacecraft needs to enter and exit the Mars atmosphere many times, and the highly uncertain density of the Martian atmosphere brings challenges for autonomous navigation. In order to realize precise state estimation, a multi-information assisted optical navigation method for Mars aerobraking is proposed in this paper. By establishing a segment dynamic model for Mars aerobraking, this method integrates IMU, radio and camera measurement information in a flexible manner. Considering the visibility of the orbiter and the changes of the objects observed by the camera, the autonomous switching criteria of the integrated navigation scheme are designed, achieving autonomous navigation in various situations during the aerobraking process. The simulation results show that this method can reduce the influence of atmosphere uncertainty, realize the high precision autonomous navigation of the whole process of Mars aerobraking, providing a feasible scheme for the state estimation of Mars aerobraking.