“龙江2号”月球轨道微卫星定轨分析

Analysis on the Orbit Determination of Longjiang-2 Lunar Microsatellite

微纳卫星深空探测任务中,通常所分配的测控资源有限,因此有必要对有限测控资源条件下微纳卫星的定轨精度进行分析。以微纳卫星深空探测为背景,采用“龙江2号”微卫星的轨道测量数据对其定轨精度进行了分析。“龙江2号”微卫星只有USB轨道测量数据,且环月段测控资源相对紧张,每天有两站跟踪,共约3~4h的轨道测量数据。首先介绍了“龙江2号”微卫星飞行任务及其飞行过程中影响测定轨的因素;其次给出了定轨的动力学模型,对微卫星地月转移段的定轨精度进行了分析;最后通过分析摄动力、动量轮卸载以及数据弧段长度的影响,给出了微卫星环月阶段所使用的定轨策略,并通过重叠弧段比较的模式,给出了微卫星环月段的定轨精度。研究结论可以为后续微纳卫星深空探测任务提供有益参考。

The TT&C (Tracking Telemetry and Command) resources are usually limited for the deep space exploration mission of micro-nano satellites. It is necessary to analyze the orbit determination accuracy under the limited resource of TT&C. The orbit determination precision of Longjiang-2 lunar microsatellite is analyzed. Longjiang-2 microsatellite only has USB orbital measurement data,and the TT&C resources in the lunar phase are relatively tight. There are two stations are used to track the Longjiang-2 satellite every day,and a total of about 3-4 hours of orbital measurement data is available. Firstly,the Longjiang-2 mission is introduced and the factors which have effect on orbit determination are presented. Secondly,the dynamical model is given. The orbit determination precision of earth-moon transfer orbit is analyzed. Lastly,the effects of perturbative force, wheel?off loading and data arc length are studied and then the orbit determination strategy is proposed. The orbit determination precision of lunar orbit is given. The conclusions can provide useful reference for the future deep space exploration mission of micro-nano satellites.