Application Of DIP Technology In Rail Dynamic Displacement Monitoring

As a common heavy-haul railway subgrade disease,mud pumping is caused by complicated reasons,with periodicity and fixed-point characteristics.The amplitude of vertical displacement of the diseased rail under train load increases,which threatens driving safety.Long-term monitoring of the vertical displacement of the rails is of great significance for guiding line maintenance,ensuring the safe running of trains,grasping the formation process of mud pumping diseases,and analyzing the cause of formation.In view of the limitation of traditional monitoring methods,this paper proposes a displacement monitoring method based on Digital Image Processing(DIP)technology.The infrared sensor camera is used to capture the movement of the structure under test under load,a dynamic video processing program was written to process the monitoring video to obtain the displacement change information of the structure under test..This monitoring method belongs to non-contact measurement,avoids the monitoring error caused by contact with the measured structure,and has the characteristics of real-time and remote unmanned monitoring,and is suitable for long-term monitoring of the dynamic displacement of heavy-haul railway rails.The main contents of this paper can be summarized as follows:(1)Determine the composition of the monitoring system based on actual monitoring needs.The main hardware includes an infrared sensor camera,a lens,a solar power supply system,and a monitoring board.The target of the monitoring board is a circular target with obvious contrast between grayscale and background.Matlab software is selected as the digital image processing software.(2)Write a dynamic video processing program based on DIP technology.The technical processes are monitoring video reading and framing processing,selection of regions of interest,digital image graying,noise reduction,binarization,and edges.Detection,digital morphology processing,sub-pixel edge positioning,target circle recognition,calculation of pixel displacement and conversion coefficient of the measured structure,and obtaining the displacement time history curve of the measured structure in physical space.(3)Through the laboratory static and dynamic monitoring tests,verify that the displacement monitoring method based on DIP technology is feasible and the monitoring accuracy meets the requirements of civil engineering surveys;determine the optimal circle fitting algorithm to identify the positioning target circle and extract digital image features information.Through comparative experiments,the relationship between the monitoring accuracy and the shooting distance,the target circle radius,the angle between the optical axis of the lens and the plane where the monitoring board is located,and other factors are analyzed.(4)In order to verify the practicability of the monitoring method,the displacement monitoring method based on DIP technology is used to obtain the time-history curve of the vertical displacement of the rail under the load of the train at the Ciyaowan station of the Baoshen Railway...