结合我国即将开展的自主火星探测计划,研究了航天器在火星探测巡航过程中利用小行星进行光学自主导航的整个过程.根据巡航段的设计轨道,给出了导航小行星的筛选条件并筛选出可用于实际任务的导航小行星序列.将自主导航的数据弧段长度设定为30d,数据观测周期为5d.采用加权最小二乘滤波算法,当数据弧段长度为30d时,导航计算的位置误差在100-400km变化,速度误差不超过0.25m/s.
Based on the upcoming self-Mars Exploration Program of China, the whole process of the optical auto-navi during the Mars exploration cruise segment is studied in this paper. Using the design orbit of the cruise section, the selection criteria and the asteroids sequence for optical navigation are given. The length of observation data arc is set to 30 days, and the period of the observation data is 5 days. Using the weighted least squares algorithm, the position error is from 100 km to 400 km and the velocity error is less than 0.25 m/s when the length of observation data arc is 30 days.