列车车轴空间直线度检测

Measurement of spatial straightness of train axle

为了准确、快速地测量列车车轴的空间直线度,构建了列车车轴空间直线度测量系统,对所述测量系统采用的空间圆拟合、空间直线拟合、直线度测量等算法进行研究。首先,根据被测对象的特征介绍了基于空间平面与空间球相切空间圆拟合算法;然后,利用随机采样一致性(RANSAC)算法迭代出符合模型的最佳点集,在列车车轴截面空间圆拟合获取的数据基础上对列车车轴截面空间圆圆心所处数据进行分析,并利用狼群算法拟合空间直线,即通过空间截面所处位置的列车车轴截面空间圆的圆心坐标拟合列车车轴空间直线;最后,利用狼群算法对列车车轴空间直线度进行测量,并把测量数据与激光跟踪仪数据进行对比。实验结果表明:基于狼群算法的列车车轴空间直线度测量精度为0.01mm,能够满足列车车轴空间直线度测量的高精度、高稳定性及测量重复性等要求。

In order to accurately and quickly measure the spatial straightness of train axle, a measurement system of train axle spatial straightness was constructed and the algorithms of spatial circle fitting, spatial straight line fitting and straightness measurement were studied. Firstly, the spatial circle fitting algorithm based on spatial plane and spatial sphere tangent was introduced according to the characteristics of the object under test. Then, the RANdom SAmple Consensus (RANSAC) algorithm was used to iterate out the best point set of the model. On the basis of the data obtained from the spatial circle fitting of the train axle section, the data of the train axle section spatial circle center was analyzed. And the wolf colony algorithm was used to fit the spatial straight line, that is, according to the circle center coordinates of the spatial circle of the train axle section at the position of the space section, the spatial straight line of the train axle was fitted. Finally, the wolf colony algorithm was used to measure the spatial straightness of train axle, and the measured data were compared with the data of laser tracker. Experimental results show that the accuracy of measuring the spatial straightness of train axle based on wolf colony algorithm is 0.01 mm, which can meet the requirements of high accuracy, high stability and repeatability in measurement of the spatial straightness of train axle.