光学学报, 2017, 37 (3): 0328003, 网络出版: 2017-03-08
TDI-CCD全景式航空相机对地目标定位的算法 下载: 603次
Geo-Location Algorithm for TDI-CCD Aerial Panoramic Camera
遥感 航空相机 对地目标定位 齐次坐标变换 误差分析 remote sensing aerial camera geo-location homogeneous coordinate transformation error analysis
摘要
为准确获取摄影区域地理位置信息, 针对时间延迟积分电荷耦合器件(TDI-CCD)全景式航空相机未配备激光测距仪的情况, 提出一种直接对地目标定位算法。依据机载定位定向系统(POS)测量的载机位置、姿态信息以及航空相机中编码器测量的俯角、位角信息, 利用齐次坐标变换求解成像系统视轴(LOS)在地理坐标下的指向角以WGS-84坐标系下定义的地球椭球模型为基础, 利用地球椭球计算理论确定目标区域经纬度信息。采用蒙特卡罗方法仿真分析了载机姿态角测量误差以及相机俯角、位角误差对视轴指向角计算精度的影响; 着重分析了摄影倾斜角和目标区域地形起伏对对地目标定位精度的影响, 指出摄影倾斜角和目标区域地形起伏越小, 定位精度越高。采用飞行实验验证了该对地目标定位算法的有效性, 在飞行高度为17750 m, 摄影倾斜角在63°~75°范围内, 对地目标定位圆概率误差小于212.96 m, 可满足工程实际需要。
Abstract
In order to obtain the geographic location of photography areas accurately, the geo-location algorithm is developed for time delay integral-charge coupled device(TDI-CCD) aerial panoramic camera without the laser range finder. Using aircraft position and attitude information measured by airborne position and orientation system (POS) along with the depression angle and position angle from the encoder in aerial camera, line of sight (LOS) pointing angle in geographic coordinate is solved by homogeneous coordinate transformation. According to the WGS-84 ellipsoidal earth model, longitude and latitude location is solved with the earth ellipsoid calculation theory. The influence of aircraft attitude angle measurement error and the depression angle and position angle measurement error on line of sight pointing angle calculation accuracy is analyzed with the Monte Carlo method. The impact of photography inclination angle and topographic change of target region on geo-location precision is investigated, which shows that the precision of geo-location is higher when the photography inclination angle and topographic change of target region are smaller. The validity of the geo-location algorithm is verified by the flight test in which the plane flies at an altitude of 17750 m and the photography inclination angle ranges from 63° to 75°. The circular error probability of target geo-location is less than 212.96 m, which meets the requirement of the project.
杜言鲁, 丁亚林, 许永森, 刘志明, 修吉宏. TDI-CCD全景式航空相机对地目标定位的算法[J]. 光学学报, 2017, 37(3): 0328003. Du Yanlu, Ding Yalin, Xu Yongsen, Liu Zhiming, Xiu Jihong. Geo-Location Algorithm for TDI-CCD Aerial Panoramic Camera[J]. Acta Optica Sinica, 2017, 37(3): 0328003.