顾及基准点误差的自由设站平差及精度分析

Free Stationing Adjustment and Accuracy Analysis Considering the Datum Point Error

观测误差和基准点误差是影响全站仪自由设站精度的2个重要因素。目前通常采用经典约束平差法进行自由设站数据处理,测站平差后,基准点误差会以原始数据误差的形式影响设站点坐标和碎部点坐标。在分析全站仪自由设站基本原理基础上,基于坐标转换思想建立同时考虑基准点误差和全站仪观测误差的自由设站平差模型,并给出具体的求解方法。实验结果表明:较大的基准点误差会对自由设站平差结果的精确度带来不利影响,基准点精度较高时,新平差模型结果与约束平差结果相当;基准点精度较低时,新平差模型结果较约束平差结果更优。

Observation errors and datum point errors are two important factors that affect the accuracy of total station free stationing.At present,the classical constrained adjustment method is usually used for data processing of free stationing.For this method,after the station adjustment,the datum point errors will affect the coordinates of stationing point and detail points in the form of initial data error.Based on the basic principle analysis of total station free stationing,we established the adjustment model of free stationing considering the datum point errors and the observation errors according to the thought of coordinate transformation,and gave the specific solution method.The experimental results show that the large datum point errors will have a negative effect on the accuracy of free stationing adjustment results.If the datum points have a high accuracy,the result of the new adjustment model is equivalent to that of the classical constrained adjustment.Otherwise,if the datum points have a low accuracy,the result of the new model is better than that of the classical constrained adjustment.