### Autonomous navigation based on Deimos lightofsight for Mars approaching phase

TANG Qingyuan, WANG Xiaolei

1. Beijing Institute of Control Engineering，Beijing 100190, China
• Online:2019-12-25 Published:2019-12-06

Abstract: The accuracy of navigation during Mars approaching phase is limited by large time delay, discontinuity of radio signal, and insufficient measurement information. An autonomous navigation method is proposed based on a succession of Deimos lightofsight (LOS) measurements relative to the spacecraft. Each position and velocity estimation is achieved through a group of Deimos LOS measurements. This method is independent of prior information such as direction of orbit asymptote. In consideration of the case that Deimos and Mars would be in the same field of view, the orbit radius can be achieved by combining Mars LOS measurement and Deimos ephemeris, which can act as supplementary measurement to improve navigation accuracy. The orbit estimation accuracy and feasibility of this navigation scheme are verified through numerical simulation, which shows that the method can meet the requirement of approaching phase orbit determination during future Mars exploration.