一种航天飞行器的INS/CNS自主导航方案

Scheme design of autonomous integrated INS/CNS navigation systems for spacecraft

传统的天文导航方法由于受水平基准精度的制约,难以进一步提高定位精度。针对INS/CNS组合导航方法对水平基准依赖的问题,提出了一种新颖的基于星光折射技术的INS/CNS自主组合导航方案。将惯性系下的非线性惯导误差传播方程作为系统状态方程,将星敏感器测得姿态和星光折射信息作为量测,采用UKF滤波算法,构成全面最优的INS/CNS组合导航。仿真结果表明,星敏感器精度为3″时,导航系统的定位精度优于200 m,姿态精度优于3″,导航定位精度随所使用的折射星数目增多明显提高,且方案在系统大角度误差条件下仍然适用。

The navigation accuracy of traditional INS/CNS is difficult to improve due to limited accuracy of horizontal reference. In view of this problem, a novel scheme design of autonomous INS/CNS integrated navigation systems was proposed based on the stellar refraction technology. The nonlinear error equation of INS in inertial frame was derived, and it was chosen as the error state dynamic equation of the INS/ CNS integrated system. The measurement was the stellar refraction angle and the attitude information of the star sensors. UKF was utilized to obtain all-state optimal estimation. Simulation results show that the precision of positioning provided by UKF is better than 200 m, the precision of attitude determination is better than 3″, and the system's navigation performance can be significantly improved. ©, 2014, Editorial Department of Journal of Chinese Inertial Technology. All right reserved.