Research On Electronic Control Detection System Of Rail Outline Parameters Based On Laser Profilers

Bofore welding,the rail' outline parameters need to be measured,such as the rail height?the rail head width?the rail buttom width?fullness of the crown?twist of the rail?the straightness and the flatness?the verticality and the bottom edge thickness.Judging from the parameters,people consider whether the rail is qualified.If the rail is qualified,weldging the rails parameters similar together.The inspection work before rail welding is very important and it matters the safty of the train running.At present,the rails inspection is carried out by manual.It is difficult to adapt to rhythm of the automated production and low efficiency.In order to solve the above problems,this article take the laser profiler as measureing device to figure out the outline data of the rails that must to be inspected.The main contents and innovation of this article are below.(1)According to the production process and working conditions,an ingenuinty and stable solution is designed.The system is consit of mechanical equipment,electrical equipment,hydraulic equipment and computer softwares.The mechanical structure is mainly divided into three sections: the front rail part,the main control measurement part and the rear rail part.To control rail transmission and the laser profilers,the Mitsubishi Q series PLC is applied in the measurement system.(2)The mathematical model of structured light measurement of laser profilometer is studied in depth,also as the relationship between the projection transformation of the camera coordinate system and the solution of internal and external parameters are studied.The distortion and correction of the camera,the calibration of the structured light plane are analyzed.And some factors affecting the accuracy of the structured light measurement are also explored.(3)For improving the dynamic response of the motion control system,combinng the neural network and traditional PID can get the parameters suitable for the current control system by modeling and training.And the influence of encoder accuracy and photoelectric switch parameter setting on motion control accuracy is analyzed.(4)The data collected by the laser profilers are pre-processed and multi-sensor data are fused.The effects of various filtering algorithms are compared.An adaptive mean filtering method is proposed to reduce the noise.Finally,the manual measurement methods are referenced.Several algorithms to obtain various parameters of rails using laser profilometer measurement data is proposed.In order to verify the repeatability accuracy of the algorithm,a rail was measured 10 times in the same situation,and the data were compared with the manual measurement data.The final results show that the relative errors and absolute errors are no more than 0.05 mm,which basically meet the requirements of production practice.