Research On Position Detection Of Railway Overhead Contact System Pillar Based On 3D Point Cloud

With the rapid economic development,China’s railway construction process has entered a new stage of development.The overhead contact system is an important part of the railway,and the construction quality control of the overhead contact system project is an important means to ensure the stable operation of the railway,and improving the detection efficiency is one of the effective methods.The pillar is one of the important components of the overhead contact system.Its positioning accuracy greatly affects the installation work of other catenary components.At present,the commonly used positioning detection methods are mainly manual measurement and judgment.There is a problem of low detection efficiency,so it is necessary to explore a relatively efficient new method for pillar positioning detection.This paper summarized the current domestic and international researches and actual application status,and proposed a new method for pillar positioning detection based on 3D point cloud.First,according to the relevant standard specifications,the positioning detection index was determined as the pillar limit,and the method for determining the safety range of the positioning detection was clarified;then a method using Unmanned Aerial Vehicle technology to obtain railway images and processing the images through software to obtain three-dimensional railway scene Point cloud data was proposed;In order to obtain the single point cloud collection of rails and pillars,a combination of secondary denoising for preprocessing,point cloud segmentation based on normal and point cloud description and recognition based on extended fast point feature histogram were proposed;and distance calculation and result judgment algorithms were proposed,it can perform the final positioning detection process on the identified pillars and rails,and visualize the results.Finally,through the empirical analysis and error analysis of a section of simulated railway,the feasibility of the new method was verified.The non-contact visual pillar positioning detection method proposed by the study can help the on-site inspectors to quickly and intuitively confirm the accuracy of the pillar installation position,promptly remind the staff to check the potential substandard pillars,and enrich the railway construction site pillar positioning detection methods.It also provides new ideas for the application of 3D point cloud and point cloud processing algorithms in railway inspection.