钢轨断面全轮廓磨耗的激光视觉动态测量

钢轨磨耗直接影响铁路运行安全，为了替代目前手工测量方式，提高测量精度和效率，研究并设计了线激光钢轨断面全轮廓视觉测量系统来实现钢轨磨耗动态测量. 首先通过计算激光视觉测量模型完成激光测量单元的结构设计，然后采用平面标定法对测量头进行精确标定，获取激光平面与传感器成像平面之间的映射关系，将拍摄的钢轨轮廓光条图像还原为实际钢轨断面轮廓；利用钢轨同一截面两侧轮廓中轨头踏面轮廓相同的特征获取钢轨断面全轮廓数据，采用ICP精确配准将钢轨两侧测量轮廓合并，其中轨头踏面轮廓采用欧式聚类和距离分割方法提取；最后以双侧未磨损轨腰轮廓及其特征点为基准，将测量钢轨全轮廓与标准钢轨轮廓进行配准对比，获取钢轨磨耗值；将线激光钢轨磨耗测量单元装载于自行研制的轨道测量小车上进行现场测量试验. 研究结果表明:该测量系统标定精度可达4.922 × 10?3 mm，测量速度可达21.6 km/h，与钢轨磨耗尺测量值对比垂直磨耗、侧边磨耗平均偏差约为0.023 mm和0.093 mm，对同一对象多次重复测量最大偏差小于0.05 mm，该测量精度满足公务要求，提高了测量效率，便于铁路测量数字化管理. 

Laser Visual Dynamic Measurement of Rail Wear on Complete Profile

Rail wear directly affects the safety of the railway transportation. To replace the current manual measurement methods and improve the measurement accuracy and efficiency, a laser rail full-profile visual measurement system was researched and designed to realize the dynamic measurement of rail wear. Firstly, the hardware structure of the laser measurement unit was designed by calculating laser vision measurement model. Then, the checkerboard plane calibration method was used to precisely calibrate the laser measurement unit to obtain the projection relationship between the laser plane and the camera plane, so the laser image of rail profile could be converted to the actual profile of rail. Based on the same characteristics of rail head profile on both sides at the same section which could be extracted by Euclidean clustering and distance segmentation, the full profile of rail section could be synthesized by ICP registration method. Finally, the waist contour and characteristic points of the unworn rail on both sides were taken as the datum, the full profile of the measured rail was compared with the standard rail profile, so rail wear was calculated from the difference between them. The laser measurement units were mounted on a self-developed rail measurement trolley for field measurement tests. The results show that the calibration accuracy of the measurement system can reach 4.922 × 10?3 mm and the measurement speed can reach 21.6 km/h. Compared with the rail wear gauge, the average deviation of vertical wear and horizontal wear of this system is 0.023 mm and 0.093 mm. The maximum deviation of the system for repeated measurement of the same object is less than 0.05 mm. The new system meets the demand of rail wear measurement, improves the measurement efficiency, and is convenient for the digital management of railway survey.