基于脉冲星和紫外敏感器的自主定轨定姿授时研究

为提高深空探测器的自主导航能力, 利用脉冲星导航的脉冲到达时间和脉冲星 角位置测量值、紫外敏感器中心天体质心相对于探测器的方向矢量和距离测量 值以及紫外敏感器输出的航天器姿态角, 以探测器在惯性坐标系下的位置和速度、 探测器本体坐标系相对于惯性坐标系的姿态角、星载时钟钟差为系统状态变量, 通过联邦扩展卡尔曼滤波器估计组合导航系统的系统状态, 并利用火星环绕段 轨道数据进行仿真实验. 仿真结果表明, 该组合导航方法能够使火星轨道器 在环绕段飞行中同时进行定轨、定姿和授时, 且具有较高的导航精度和授时能力. 

Autonomous Orbit and Attitude Determination Including Time Prediction Based on XNAV and Ultraviolet Sensor

In order to improve the autonomous navigation ability of deep space spacecraft, the X-ray detector and ultraviolet sensor were applied simultaneously. The attitude angles and errors of time of pulse arrival of pulsars were measured by X-ray detector, and simultaneously the central body's barycenter line-of-sight vector, distance between spacecraft and the barycenter, and the attitude angles were measured by ultraviolet sensor. The state of the integrated navigation system includes position and velocity vectors in inertial coordinate system, attitude angles and clock error. The Federated Extended Kalman Filter (FEKF) was applied to estimate the state of the navigation system. Simulation results in Mars orbit demonstrate that this method can fulfill orbit determination, attitude determination and clock time prediction simultaneously. Moreover, this integrated navigation system can provide high navigation precision and predict clock time effectively.