基于导航星域和K矢量的快速星图识别算法  

A Rapid Star Identification Algorithm Based-on Navigation Star Domain and K -Vector

作　　者：邢飞[1] 尤政[1] 董瑛[1] 

机构地区：[1]清华大学精密仪器与机械学系,精密测试与仪器国家重点实验室,北京100084

出　　处：《宇航学报》2010年第10期2302-2308,共7页Journal of Astronautics

基　　金：国家自然科学基金(60807004);空间智能控制技术国家级重点实验室项目资助

摘　　要：星图识别算法是星敏感器的关键技术,快速性和可靠性一直是对其评价的重要指标。提出了基于K矢量查找表和导航星域联合进行超快速星图识别的方法。首先根据星敏感器视场和所能敏感的星等建立全天球导航星表;再依据K矢量的原则对全天的导航星按照星对角距进行分类,建立星对角距所对应导航星的K矢量和K矢量查找表。利用星敏感器视场中的4颗星构成6组星对角距,将其中的5组星对角距所对应K矢量查找表域的星对组进行导航星表域(简称导航星域)的变换,根据另外一组星对角距所对应的K矢量查找表域的值对前面5组导航星域的值同时进行索引比较,直接找到了满足条件的4颗导航星,即完成全天的星图识别。最后,通过计算机仿真,实验室模拟和真实星空实验三个层次验证了此方法的可靠性和快速性。Star identification algorithm is a key technology for a star tracker,and the rapidness and reliability are always important evaluation indices of the algorithm. A rapid star identification method based on K -vector lookup table with navigation stars domain is brought forward in this paper. Firstly,a navigation stars catalog according to the field of view （ FOV） and the visual magnitude sensed by the star tracker,secondly the navigation stars are classified according to angular separations of star pairs in the K -vector principle,and K -vectors of navigation stars corresponding to angular separations of star pairs and a K -vector lookup table are set up. Utilizing the 6 angular separations of star pairs of composed of 4 stars in the star tracker FOV,this algorithm firstly transforms the star pair group in the lookup table domain corresponding to 5 star pairs’angular separations into the navigation star domain,then compares the index of K -vector lookup table domain corresponding to the angular separation of other star pair group to the index of the navigation star domain of 5 star pairs’angular separations,directly find the corresponding 4 navigation stars and finish the star pattern identification. At last,the reliability and the rapidness of this algorithm are confirmed through three ways,computer simulation,lab emulation and a real star sky experiment.

关 键 词：星图识别 星敏感器 导航星域 K矢量 真实星空 

分 类 号：V448.22[航空宇航科学与技术—飞行器设计]