在卫星摄影测量中,相机参数经过在轨标定后,仍有随时间变化的低频误差,在无地面控制点情况下,这类低频误差影响卫星影像的定位精度.基于光学自准直原理的光轴位置测量设备可以在轨实时监测相机参数的变化情况,对于全球实时或准实时影像处理,可以使用该测量数据削弱低频误差对立体影像定位精度的影响.本文基于光轴位置测量设备的工作原理,建立了光轴位置测量数据辅助立体影像定位的模型和算法,并利用高分十四号卫星数据进行了试验验证.试验结果表明,利用光轴位置测量数据辅助立体影像定位,无须频繁地进行相机参数在轨标定,也无须地面控制点支持,即可实现卫星影像高精度定位,且全球范围内影像无地面控制点定位精度基本一致,平面精度约为1.87 m,高程精度约为0.73 m.
Stereo image positioning technology without ground control points assisted by optical axis position measurement data
In satellite photogrammetry,after the on-orbit calibration of the camera parameters,there are still low-frequency errors that vary with time and affect the location accuracy of satellite images in the absence of ground control points.Optical axis position measurement devices based on the optical self-collimation principle can be used to monitor the on-orbit camera pa-rameter changes in real time.For global real-time or quasi-real-time image processing,this measurement data can be used to reduce the impact of low-frequency errors on the location accuracy of stereo images.Based on the working principle of the opti-cal axis position measurement device,this paper establishes a model and algorithm for assisting stereo image positioning with optical axis position measurement data,and conducts experimental validation using GF-14 satellite data.The experimental re-sults show that the use of optical axis position measurement data to assist stereo image positioning can achieve high location accuracy of satellite images without frequent on-orbit calibration of camera parameters and ground control points,and the location accuracy of ima-ges without ground control points is basically the same worldwide,reaching about 1.87 m in plane and about 0.73 m in elevation.
satellite photogrammetryon-orbit calibrationoptical axis position measurementlocation without ground control pointsGF-14 satellite data
万方数据
维普
