基于UKF和信息融合的航天器自主导航方法

X射线脉冲星导航利用X射线辐射脉冲到达时间(Time of Arrival,TOA)作为信息输入,星敏感器导航利用星光角距等作为信息输入,是两种不同机理的天文导航方法.提出一种将脉冲星TOA和星敏感器星光角距测量结合的信息融合天文自主导航方法,设计了一种利用激光光量子模拟脉冲星X射线辐射光子的半物理仿真系统用于算法验证,并基于无迹卡尔曼滤波(Unscented Kalman Filter,UKF)使用真轨道参数做了仿真试验.结果表明,基于UKF的信息融合方法比基于EKF (Extended Kalman Filter)的信息融合方法性能更好,与仅使用脉冲星或星敏感器的导航方法相比,能将位置估计精度分别提高52.7％和43.6％,速度估计精度分别提高82.2％和70.5％.

Method of Autonomous Celestial Navigation Based on UKF and Information Fusion

X-ray pulsars navigation uses the time of arrival(TOA) of the X-ray pulse radiation to resolve the position.Star sensor based navigation uses the angle between line of sight to the star and the center of earth to resolve the position.The mechanisms of the two navigation systems are different from each other.An information fusion celestial autonomous navigation method was proposed by hybriding the pulsars TOA and elevation angle of star sensor measurement.And the simulation experiments based on unscented Kalman filter(UKF) using real orbit parameters were carried out.A hard-in-loop simulation system which uses the laser quantum to emulate the X-ray quantum of pulsars was designed to test the method.The results show that,comparing to the methods based on pulsars or star sensor only,the estimation accuracy of position and velocity of the proposed method can increase 52.7%,43.6%,82.2% and 70.5% respectively,and its performance is better than extended Kalman filter(EKF) information fusion method.