长度投影变形对CPⅢ平面网精度影响的计算实验

Computational experiments about the influence of projective defermation on horizontal CPⅢ central network

为探讨长度投影变形对CPⅢ平面网精度的影响,选择3段不同长度的实测CPⅢ平面网,作为对照,仿真一段没有投影变形的CPⅢ平面网,然后对这4段CPⅢ平面网分别添加不同大小的边长投影变形改正,统计不同的边长投影变形改正下对应的CPⅢ平面网的精度,发现CPⅢ平面网精度最佳时的边长改正与由原始观测值自由网平差后坐标转换中的尺度比参数K一致,得出了采用K值作为边长改正可以最大程度的提高CPⅢ平面网精度的结论。这一结论能为正确进行CPⅢ平面网数据处理提供有益的参考。

In order to investigate projective deformation’s impact in CPIII plane measurements, This paper has chosen three segments of different lengths measured CPIII plane, as a contrast, another CPIII plane without projective deformation has been simulated. Then , different proportions changes have been added on measured distances in this four planes, this paper analysis the precisions of all the control points in different proportions, and find out the most precisions will be achieved by using the value of K, which calculated from free-network adjustment. This conclusion is properly provide a useful reference in CPIII plane data processing.