Research On Control System Of Electron Beam Rail Surface Repair Based On 3D Printing

At present,with the rapid development of high-speed rail technology in China,the growth rate of high-speed rail lines is accelerated and the train speed is greatly improved.In order to meet the stability and safety of train operation,it is necessary to ensure the quality of rail repair and reduce accidents.In this dissertation,3D printing technology and electron beam welding technology are used to study the surface repair control system of electron beam rail.In this dissertation,the overall design of electron beam rail surface repair control system based on 3D printing is first carried out,and then it is divided into five subsystems,including vacuum electron gun system,motion platform system,visual imaging system,wire feeding system and power supply system.The vacuum electron gun system,motion platform system and visual imaging system are mainly studied.The selection of welding technology and the design of vacuum control system are carried out in the vacuum electron gun system.The electron gun differential pumping technology and plasma extraction window technology in non-vacuum welding technology are selected.The vacuum control system adopts PLC control as the core of the vacuum control system.The vacuum electronic gun control system is designed.After determining all the hardware required for the system,the ladder diagram of PLC internal operation is compiled.The motion platform system adopts three-axis linkage motion mode,and each axis uses a linear screw slider.The platform can carry the screw system and the visual imaging system for XYZ three-direction motion.In this dissertation,the industrial computer and motion control board are selected as the control core of the motion platform system,the servo motor and servo drive are used as the driving device of the motion platform system,and the screw slider is used as the execution structure of the motion platform system.The required hardware is selected and the motion platform control program is written.The hardware connection of the motion platform system is debugged.The visual imaging system adopts non-contact measurement method and is designed based on the principle of structured light imaging.The camera is calibrated after determining the geometric information conversion mode between the object and the space object in the image by coordinate system conversion.The left and right cameras of the three-dimensional scanner were photographed and calibrated in the Stereo Camera Calibrator plug-in of MATLAB software to obtain the internal and external parameters of the camera and analyze the error.The three-dimensional scanner is used to scan the rail surface,and the point cloud data of the rail surface are obtained.The image processing is carried out by Geomagic Studio software.After extraction of rail surface defects,point processing,polygon processing and surface processing are carried out.After virtual modeling,entity modeling is carried out in Creo 3D modeling software and converted into STL file.The file is imported into Cura software for slicing.In this dissertation,the G code interpreter is written according to the G code characteristics of the slicing file.The preprocessing,statement analysis and code interpretation of the slicing information are carried out,and the G code file is converted into a motion control board card identifiable program.Finally,the sub-system software is designed and developed based on C# language.The system has many advantages such as complete function,friendly interface,strong portability and easy operation.