Research On Three-dimensional Measurementtechnology Of Bogie Wheelbase Dimension Andparallelism

In this paper,aiming at the key technology of 3D measurement of wheelbase size and parallelism of bogie,a measurement system of wheelbase size and parallelism of train bogie is designed and constructed.the calibration technology of line structure light,the 3D reconstruction technology of train bogie wheelset and the measurement of wheelbase and parallelism of train bogie are studied.According to the functional design requirements and technical index requirements of bogie,the measurement system of wheelbase size and parallelism of train bogie is established.The non-contact laser sensor is used as the measuring sensor,and four groups of double-eye line structured light measuring units are set up in four wheel positions of two wheelsets of bogie,which can be used to obtain the three-dimensional data information of train bogie wheelset.When obtaining the surface information of the object,the CCD camera and the laser projector are used to build the line structured light sensor as the main measuring unit.In order to realize the accuracy of obtaining the information,the line structured light sensor needs to be calibrated,and the special-shaped block calibration method based on GA-RBF is used.The matrix is used to extract the light strip,and the purpose of measurement and calibration is realized.According to the characteristic of special lathe machining and forming of bogie wheelset,it is regarded as the iteration of spatial circle along the axis,which simplifies the calculation of reconstruction.At the same time,due to the limited measurement range of single line structured light sensor,the three-dimensional point cloud data obtained by frequency domain splicing is used to register the obtained 3D point cloud data,and on this basis,the three-dimensional reconstruction of bogie wheelset is completed.According to the measurement characteristics of bogie parallelism,it is necessary to construct a reference line for line-to-line parallelism measurement,and the straight line fitting method based on wolf swarm algorithm is used to fit the front wheel axis of bogie,and the axis point cloud data of bogie rear wheel are regarded as the measured object,and the parallelism measurement of train bogie is realized.