Research On Optical Autonomous Navigation For Deep Space Exploration

Due to the advantages of reducing the burden of ground station support,enhancing the viability and expanding the special application of spacecraft,autonomous navigation has been successfully validated and begun to apply inforeign deep space missions. It will be a key technology for deep spacemissions in future. As the lack of ground station tracking resources, thedevelopment of autonomous navigation will become more important forChinese deep space exploration program. Under the background of Marsmission, the research on optical autonomous navigation for cruise phase andapproach phase is studied intensively.Firstly, the dynamical model, observation model and filtering algorithmsincluding weighted least squares algorithm, extended Kalman filter andunscented Kalman filter of optical autonomous navigation for cruise segmentand approach segment are presented.During the Mars cruise phase, the application of optical autonomousnavigation based on the asteroids’ line of sight is researched. According to thelaunch window of Mars, the nominal orbit of coast phase is designed. Thetheory of optical autonomous navigation by using asteroids is presented andproved. Then, the detailed analysis of the navigation asteroid selection criteriaassociated with the selection steps is summarized. Combining the nominaldesigned orbit, the asteroids sequences for optical navigation are given. At last,two different initial state errors are set to evaluate the performance of the batchfiltering and recursive processing filtering, and an optimal choice of filters ismade for real task.During the approach phase, the method of optical autonomous navigationby using Mars is studied. The standard orbit is designed firstly. Through theobservability analysis of the navigation system and the observation model, thefeasibility of only using Mars optical information for autonomous navigation isproved. Based on the parameters of MESSENGER’s MDIS camera system, theobservation data is simulated. And the simulation results by using Extended Kalman filter and Unscented Kalman filter respectively show that the stabilityand accuracy of the results meet the requirement of actual task.Based on China’s upcoming Mars program, this thesis gives an in-depthresearch on optical autonomous navigation. It has some theoretical and practicalvalue, and offers a meaningful reference for the real Mars mission.