A Universal Coordinate Computation Model Based on Least Squares Adjustment Method

This paper presents a universal model for calculating point coordinates based on least squares adjustment method.The measured angles and distances are first converted into the direction and distance observations, then the error equations are constructed and the unknown coordinate parameters and accuracy are derived from a universal iterative adjustment computation.The proposed model has the characteristics of high accuracy and generic algorithm.Using Levenberg-Marquardt least squares iterative adjustment,initial values of unknown points are given graphically according to the geometric relationship among the measured objects,and the results are obtained robustly.The often-used total eleven coordinate calculation methods are derived on the basis of the proposed model in detail,and the implementation of the model is illustrated through a case study.