一种基于间接平差的免置平设站方法

A free-stationing method of ETS without leveling based on indirect adjustment

置平是全站仪设站必不可少的先期工作,但手动置平操作繁琐,自动化水平低,影响设站的工作效率。同时,这种以精确置平为先决条件的设站方法也不利于移动站车载全站仪的快速设站和测量。提出一种基于间接平差的免置平设站方法,以高程、平面及姿态的联立求解为基础,通过变量代换、泰勒展开、矩阵求逆等方法求全站仪站点位置和姿态,采用验后精度求权和平差迭代的方法提高设站精度。该方法原理清晰,物理意义明确,打破了置平才能设站的传统。计算机仿真和线路试验表明,该免置平设站方法具有较高设站精度,能够达到高速铁路测量的精度要求。

Leveling ETS is an essential preparation work of free-stationing in engineering survey practices.However,the leveling operation is cumbersome and insufficiently automated,which affects the efficiency of free-stationing.Meanwhile,this free-station method based on precise leveling is not applicable to the rapid free-stationing and measurement of mobile ETS.A free-stationing method of ETS without leveling based on indirect adjustment was proposed.Based on the simultaneous solution model of elevation and plane,the methods of variable substitution,Taylor expansion and matrix inversion were used to calculate the position and attitude of ETS.The method of weighted calculation by post inspection accuracy and adjustment iteration were used to improve the accuracy of free-stationing.The principle is clear,physical meaning is sound,and it eliminates the conventional prerequisite procedure of leveling for free-stationing operations.Computer simulations and field measurement trials show that this method has high accuracy and meets the precision requirement of high speed railways.