Research On The Compensation Method Of Vehicle Movement Posture Attitude To Track Position Detection

Vehicle mounted track position detection is a common method for rail inspection, the measuring equipment used in the body as the reference frame. Influence of line environment and traction force, random vibration of the vehicle body relative to the track,but the track inspection data is based on the track as the reference frame. Need to shift the body vibration caused by the vehicle body as the reference system for the detection value conversion to the track reference system, to compensate for the relative displacement of the vehicle and the track reference system.In this thesis, the mapping relationship between the body coordinate system and the track coordinates is established by machine vision method, an experimental system consisting of a vision sensor and a inclinometer is constructed. Studied on the detection method of vehicle motion attitude, the vibration offset compensation of the track type position detecting vehicle is realized. The main research contents include:1) extraction of contour based on EPTA parallel thinning algorithm, to obtain the skeleton map of the section of rail, extraction of rail contour line segment point set based on Hough transform, Multiple contour points are obtained;2) based on the hand eye calibration method of binocular vision, accurate calibration of the vision sensor and the body coordinate system is carried out, optimization of calibration results with the least square method, mapping the orbital coordinate system to the vehicle body coordinate system;3) the experimental platform of vehicle motion attitude measurement is set up, software design of upper computer using MFC platform, enable the experimental platform to quickly capture images, simple realization of vibration displacement calculation.Design verification experiments and simulation experiments, preliminary design of vehicle motion attitude measurement and compensation calculation system based on MFC platform, including the realization of the function of high-speed image acquisition. Verification experiment design Y, Z two direction known offset route, using this system to collect data, calculate the offset. The results compared with the original design route bit phase shift, the static average error is 0.5606 mm, the average error of dynamic motion is 1.3539 mm, error within the allowable range. The overall measurement accuracy of the simulation experiment is improved by 0.166 mm. Experimental results show that the compensation method can achieve higher precision compensation based on the vehicle track type position detection system.