三维坐标转换中高程误差对转换精度的影响

摘要

Based on Bursa-Wolf coordinate transformation model and parameter solving methods, a mathematical model for the 3-D accuracy of coordinate conversion for arbitrary measured point in the surveying area is derive with the theory of error propagation. According to the an alysis of the mathematical model, it can be concluded that the variation of conversion accuracy of measured point presents a parabola distribution with the change of altitude. Meanwhile, when the variation of altitude is in the scope of -100～1 000 m, the conversion accuracy is about 1O-2 m, which has a trivial effect on the coordinate transformation. The theoretical validity of the conclusions was proved by experiment.%以Bursa-Wolf坐标转换模型和参数求解方法为基础,根据误差传播理论,推导出测区内任意待转换点三维坐标转换精度数学公式.通过对该数学模型的分析可得:公共点所在测区内待测点的转换精度随高程变化呈抛物线分布.当高程在(-100m,1000 m)区间变化时,转换精度在10-2量级浮动,对坐标转换的影响很小.最后通过算例验证了结论的正确性.