测绘相机立方镜与星敏立方镜转换矩阵的标定

Calibration of transition matrix on cubic prisms in mapping camera and star sensor

传输型立体测绘卫星利用测绘相机进行摄影测量时,需要确定测绘相机在惯性坐标系中的姿态。确定姿态时,首先由星敏感器测量得到星敏测量坐标系在惯性坐标系中的姿态,然后通过星敏测量坐标系与星敏立方镜的转换矩阵、星敏立方镜与测绘相机立方镜的转换矩阵,得到测绘相机测量坐标系在惯性坐标系中的姿态。文中介绍了各坐标系的定义,根据星敏立方镜与测绘相机立方镜坐标系的关系,利用4台经纬仪测量系统分别建立星敏立方镜和测绘相机立方镜的坐标系以及2坐标系间的转换矩阵,介绍了2个立方镜坐标系的标定方法,多次测量结果表明,最大标定误差为1.011 6",优于2"(1σ),满足立体测绘精度的要求。

It is necessary to determine camera postures in inertial coordinate systems, when the mapping camera is used in a photogrammetry for a transport stereo mapping satellite. In determining the camera postures, the postures of star sensor measuring system in the inertial coordinate system were measured by star sensors, then, the postures of the mapping camera measuring system in the inertial coordinate system were obtained by the transition matrix between star sensor measuring system and the cubic prism in star sensor and the transition matrix between the two cubic prisms in the star sensor and mapping camera. This paper introduces the definition of coordinate systems. By using the measuring systems of four theodolites, we establish coordinate systems on two cubic prisms respectively and a transition matrix for the coordinate systems. The calibration method of two coordinate systems is presented. The measuring results from many experiments show that the maximum calibration error is 1.011 6″,which is better than 2″（1σ） and satisfies the precision requirement of the stereoscopic mapping.