基于双视线测量的相对导航方法

A Method of Double Line-of-sight Measurement Relative Navigation

对非合作目标自主交会中的中远程相对导航问题进行研究。首先,给出二阶近似的航天器相对轨道动力学方程,并对视线(LOS)导航方法的可观测性进行了分析。然后,提出基于双视线测量的相对导航方案。该导航方案中,系统过程噪声模型采用适用于航天器远距离相对运动的轨道动力学方程;量测量包括目标对两个追踪航天器的视线角和追踪航天器之间的基线方位与长度,并以此建立了量测方程。最后,采用扩展卡尔曼滤波(EKF)算法解算目标的相对位置和速度。通过数值仿真验证了该导航方案的有效性,并分析了各航天器间几何参数的变化特点。

Relative navigation for long or medium range autonomous rendezvous with a noncooperative target is discussed. Second-order approximation of the relative dynamics equations between the two spacecraft is presented. Observability of the line-of-sight （LOS） navigation is analyzed, and a double LOS measurement relative navigation strategy is proposed. A processing noise model of the relative navigation system is developed based on the relative dynamics equations between spacecraft within long distances. A measurement model is established, which includes the LOS angles of the target relative to the two spacecraft and both the azimuth and the length of the measurement baseline. An extended Kalman filter （EKF） algorithm is used to estimate the relative position and velocity of the target. The simulation results demonstrate the validity of the navigation method and are used to analyze variation characteristics of the geometric parameters among the spacecraft.