红外与激光工程
紅外與激光工程
홍외여격광공정
INFRARED AND LASER ENGINEERING
2014年
6期
1812-1817
,共6页
魏新国%李延鹏%李健%江洁
魏新國%李延鵬%李健%江潔
위신국%리연붕%리건%강길
多视场星敏感器%天文导航%星光角距
多視場星敏感器%天文導航%星光角距
다시장성민감기%천문도항%성광각거
multi- FOV star tracker%celestial navigation%starlight angle
传统航天器自主天文导航需要星敏感器、红外地平仪、磁强计等多种敏感器采集导航数据,增加了航天器的成本和复杂度。利用多视场星敏感器的特点,分别对恒星与地球进行成像,在完成姿态测量的同时,得到地心矢量信息,从而进行自主天文导航。首先建立地球几何模型,结合航天器轨道参数与多视场星敏感器的安装布局,实现各个视场内地球边缘的成像模拟,使用Steger算法提取地球边缘。综合考虑地球扁率的影响,对不同视场中观测到的地球边缘进行拟合得到精确地心矢量,最后进行基于星光角距的直接敏感地平导航仿真。仿真结果表明,在一个视场观测恒星,另外两个视场观测地球边缘的布局情况下,地心矢量精度和导航位置精度分别达到0.0172o(1σ)和190 m(1σ)。
傳統航天器自主天文導航需要星敏感器、紅外地平儀、磁彊計等多種敏感器採集導航數據,增加瞭航天器的成本和複雜度。利用多視場星敏感器的特點,分彆對恆星與地毬進行成像,在完成姿態測量的同時,得到地心矢量信息,從而進行自主天文導航。首先建立地毬幾何模型,結閤航天器軌道參數與多視場星敏感器的安裝佈跼,實現各箇視場內地毬邊緣的成像模擬,使用Steger算法提取地毬邊緣。綜閤攷慮地毬扁率的影響,對不同視場中觀測到的地毬邊緣進行擬閤得到精確地心矢量,最後進行基于星光角距的直接敏感地平導航倣真。倣真結果錶明,在一箇視場觀測恆星,另外兩箇視場觀測地毬邊緣的佈跼情況下,地心矢量精度和導航位置精度分彆達到0.0172o(1σ)和190 m(1σ)。
전통항천기자주천문도항수요성민감기、홍외지평의、자강계등다충민감기채집도항수거,증가료항천기적성본화복잡도。이용다시장성민감기적특점,분별대항성여지구진행성상,재완성자태측량적동시,득도지심시량신식,종이진행자주천문도항。수선건입지구궤하모형,결합항천기궤도삼수여다시장성민감기적안장포국,실현각개시장내지구변연적성상모의,사용Steger산법제취지구변연。종합고필지구편솔적영향,대불동시장중관측도적지구변연진행의합득도정학지심시량,최후진행기우성광각거적직접민감지평도항방진。방진결과표명,재일개시장관측항성,령외량개시장관측지구변연적포국정황하,지심시량정도화도항위치정도분별체도0.0172o(1σ)화190 m(1σ)。
The traditional methods for spacecraft autonomous navigation need several sensors, such as star sensor, infrared horizon sensor and magnetometer, to collect navigation data. As a result the load of spacecraft will gain in weight, size and power. Based on the advantages of multi- field of view (FOV) star tracker, an autonomous navigation method was proposed which used multi- FOV star tracker (MFST) to image the star and the earth respectively and got the orientation vectors of them. Combining with the orbit parameters of the spacecraft and the layout of the MFST, a mathematic model of the earth imaging was set up to implement the earth edge images in every single FOV. The Steger method was used to determine the earth edge in the images. Considering the earth oblateness, the orientation vector of the earth will be obtained through circle- fitting the earth edge points in each FOV. With the configuration that one FOV measures the navigation star and the other two FOV measures the earth edge, the autonomous orientation based on the starlight angle is simulated and the result indicates that the accuracy of the earth vector and the spacecraft position respectively reaches 0.017 2o(1σ) and 190 m(1σ)