Study On Plane Curve Reconstruction Method Of High- Speed Passenger Dedicated Line

With the gradual acceleration of the speed of high-speed railways in China,the role of trains and tracks has become increasingly significant,and the smoothness of the lines has been gradually destroyed.In order to ensure the safe and smooth operation of the train,it is necessary to reconstruct the unfair road.The traditional track-based surveying of the rails can no longer meet the accuracy requirements.Therefore,a model suitable for the reconstruction of the plane curve of the high-speed passenger dedicated line must be established.This paper mainly focuses on the plane measurement method,linear segment method,fitting method and optimization method of high-speed passenger dedicated line.The main research contents and conclusions include the following aspects:(1)Analyze the traditional railway reconstruction measurement method.The analysis results suggest that a high-speed passenger dedicated line plane control network must be established for the high-speed passenger dedicated line,and that the accuracy of the joint measurement should be measured by the total station and the rail inspection vehicle based on the coordinate method.To meet the needs of high-speed passenger dedicated line measurement accuracy.The stability of the control points was analyzed,and the total stations were set up freely to accurately measure the trajectory points of the line,providing an accurate data source for line segmentation,line fitting,and line shape optimization of line points.(2)After the coordinates of the orbital point are collected,linear segmentation is performed.The elliptical curvature method is used to calculate the curvature of the discrete point,and the curvature-mileage diagram is drawn.The outline of the plane line shape is roughly segmented based on the curvature change,and the planar linear shape segmentation is performed through the iterative calculation method.(3)Linear fitting is performed on the basis of linear segmentation.Orthogonal least-squares method is used to fit the circuit plane lines,so that the sum of the squared deviations is minimized.The concept of robust estimation is introduced for the possible presence of gross errors in the measurement.By assigning different weights to gross and abnormal values,the effect on fitting results is reduced.(4)In order to meet the requirements of plane linear maintenance of high-speed passenger dedicated lines,based on the fitting results,it is necessary to optimize the radius of the curve and the length of the transition curve.For the objective function that is difficult to find the derivative or cannot find the derivative,we choose to use the gradient projection method to optimize it.By measuring the plane measured coordinates of a high-speed passenger dedicated line,the method described in the article is used to segment,fit and optimize the feasibility of the method and the good results are achieved.