航天器星敏感器自主定位方法及精度分析

The method of autonomous position determination using star sensor and analysis of precision for spacecraft

用星敏感器和地平仪测量星光与地平之间的“星光仰角”为观测量 ,利用推广卡尔曼滤波方法实时估计航天器的最佳位置 ,使航天器在失去地面遥控的情况下 ,能够自主准确地确定运行轨道。由于航天器自主定位系统在工作期间会受到硬、软件等诸多因素的影响 ,因而使其定位精度达不到预计要求。在此我们通过大量仿真计算 ,指出一些对自主定位系统精度影响较大的因素 ,并对它们进行了比较分析。

The best position of spacecraft is real timely determined by using the extended kalman filtering in order that spacecraft can run in scheduled orbit autonomously and accurately without the remote control of ground command.The elevation angular of star is observed by star sensor and horizontal instrument.During the work period of spacecraft,the system can be influenced by many factors related to hardwere and softwere,the precision of orbit determination can be short of request.By emulating calculation,some factors that influence largely on the precision of determining position are pointed out,compared and analyzed earnestly.