基于精化后似大地水准面模型的ADS80空三加密精度分析

Accuracy analysis of ADS80 space triple encryption based on refined quasi geoid model

为解决徕卡ADS80推扫式航摄仪在大面积航空摄影测量空三加密中投影变形的问题,文中对在航空摄影测量时椭球高至正常高投影转换问题进行了研究。结合青海省历年来的CORS站点及基础控制点,利用移去—拟合—恢复的方法拟合出实验区似大地水准面模型,利用该模型将实验区像控点椭球高归算至正常高,将该结果用于空三加密时,无须进行传统实验研究后的坐标投影及转换。经验证基于此方法的加密结果符合规范要求,即解决了高程投影问题,又提高了测绘工作效率。

In order to solve the problem of projection distortion of Leica ADS80 push broom aerial camera in large area aerial photogrammetry,the transformation from ellipsoid height to normal height is studied.Based on the CORS stations and basic control points in Qinghai province over the years,the quasi geoid model of the experimental research area is fitted by the method of removing fitting recovering.The ellipsoid height of the image control points in the experimental area is calculated to the normal height by using the model,and the result is used for space three encryption without the need of coordinate projection and transformation after the traditional experimental research.It is verified that the encryption results meet the standard requirements,namely.It solves the problem of elevation projection and improves the efficiency of surveying and mapping.