车载移动测量系统前方交会中的误差分析

Error analysis of vehicle mobile mapping system in forward intersection

车载移动测量系统是由多个传感器集成的系统,定位精度受到很多因素的影响。首先简要介绍了车载摄影测量中内外方位元素的计算方法;其次,针对线性法前方交会求解中符号矩阵的直接求逆内存占用大的问题,提出利用杜利特尔分解(LU分解)的方法,推导出了前方交会的解算公式;最后,针对短基线小交会角的情况利用误差传播定律分析了各误差源对最终定位结果的影响,对于进一步研究车载移动测量系统具有一定的参考意义。

Vehicle mobile mapping system is a kind of multi-sensor integrated system, the positioning accuracy of which is affected by many factors. In this paper, the calculating method of inside and outside azimuth elements in vehicle photogrammetry is introduced at first. And then, a solution formula of forward intersection is deduced with the method of Doolittle decomposition （LU decomposition） so as to solve the problem that the direct inverse operation of symbol matrix in linear forward intersection requires large memory. Finally, the error propagation law is used to analyze the effect of each error source on the final positioning results for short baseline and small intersection angle, the reserach result can provide a few reference value for further study of vehicle mobile mapping system.