“天问一号”探测器轨道确定及精度评估  

Orbit determination and accuracy evaluation of Tianwen-1 probe

作　　者：满海钧 曹建峰 鞠冰[1,2] 李勰 孔静 刘山洪[1,2] MAN Haijun;CAO Jianfeng;JU Bing;LI Xie;KONG Jing;LIU Shanhong(National Key Laboratory of Science and Technology on Aerospace Flight Dynamics,Beijing 100094,China;Beijing Aerospace Control Center,Beijing 100094,China)

机构地区：[1]航天飞行动力学技术重点实验室,北京100094 [2]北京航天飞行控制中心,北京100094

出　　处：《测绘学报》2024年第7期1288-1297,共10页Acta Geodaetica et Cartographica Sinica

基　　金：国家自然科学基金(12203002;11973015;42241116)。

摘　　要：“天问一号”是我国首个自主火星探测任务,高精度轨道确定是圆满完成工程任务和科学数据分析的基础。针对“天问一号”不同飞行阶段的轨道特性、力学环境及测量水平,本文采用不同策略进行轨道确定并评估精度,在地火转移阶段轨道精度优于4 km,环火停泊阶段轨道精度优于1 km,中继通信阶段轨道精度优于100 m;双程测距数据精度约为0.5 m,1 s积分双程测速数据精度约为0.2 mm/s,VLBI时延数据精度约为0.3 ns。“天问一号”定轨精度主要受到太阳光压和姿控模型误差影响,在定轨过程中求解光压系数和经验加速度十分必要。“天问一号”探测器光压系数与经验加速度存在一定程度的耦合,需要添加先验约束信息。For China s first Mars exploration mission,Tianwen-1,high accuracy orbit determination is the cornerstone for fulfilling engineering goals and scientific exploratory objectives.This study adopts a variety of orbit determination approaches based on the characteristics of the orbit,the dynamic environment,and the observational quality of different stages.It then evaluates the orbit accuracy by comparing overlapping arcs.Modeling errors for solar radiation pressure and attitude control thrust are the main obstacles preventing the high accuracy orbit of Tianwen-1.Some model errors can be removed by resolving the solar radiation pressure coefficient and empirical acceleration parameters during the orbit determination estimation.However,because of the special spacecraft attitude,the combined estimation of the solar radiation pressure coefficient and empirical acceleration parameters leads a clear coupling relationship,but adding a priori constraint information is a way to decrease the correlation between them.In the interplanetary cruise stage,the orbit accuracy is better than 4 km,1 km in the parking stage,and 100 m in the relay communication stage,according to the results of an overlapping orbit.Furthermore,the accuracy of two-way range measurement is about 0.5 m,the two-way Doppler measurement is about 0.2 mm/s at 1 s integration time,and the VLBI delay measurement is around 0.3 ns.

关 键 词：天问一号 精密定轨 太阳光压 姿控推力 

分 类 号：P228[天文地球—大地测量学与测量工程]