Abstract:

High-precision and all-time spacecraft autonomous navigation is the development direction in the space technology application, and is also the foundation for the actual on-orbit application for the spacecraft. An autonomous navigation algorithm for spacecraft base on the astronomical information of the sun, the earth and the moon was researched. Firstly, by using the dynamics equations and the angles between the spacecraft, the earth, the sun and the moon, as well as the distance between the spacecraft and the earth as the state model and observation model respectively, the navigation system was established. Then, the autonomous navigation algorithm was presented. When the sun and the moon were observable, the autonomous navigation through the nonlinear cubature Kalman filter (CKF) was adopted; and the high-precise orbit prediction algorithm was used to predict the orbit by using the track dynamics directly during the eclipse. Finally, the numerical simulation was provided. Results show that the positioning accuracy of this method is lower than 2km, which is enough to satisfy the autonomous navigation.

Key words:

spacecraft, autonomous navigation, eclipse, observability, cubature Kalman filter, orbit prediction