Abstract: A method for autonomous navigation of deep space exploration spacecraft was proposed. In order to cope with the error of the spacecraft orbital dynamics model in deep space exploration, not only the radial velocity of the spacecraft relative to the sun, but also the line of sight vector of the asteroid was measured. The position information obtained by the asteroid's line of sight vector was calculated by the least squares method, and the state estimation error caused by the inexact dynamic model in the extended Kalman filter was modified by the improved information fusion method. At the same time, the observability of the model was calculated and analyzed. The simulation results show that the dependence of the algorithm on the dynamic model is significantly lower than that of the other algorithms. Under the same model precision, better result can be obtained.

Key words: autonomous navigation for deep space exploration, radial velocity, line of sight vector of the asteroid, least squares method, extended Kalman filter, observability