Research On Data Processing Method Of Track Dynamic Detection Based On Strapdown Inertial Navigation System

In recent years,China’s railway and urban rail transit construction has developed more rapidly.For railways and urban rail transit,the track is the basis for the safe operation of the traffic line,the track of good or bad state to a certain extent,directly determines the subway and railway safety,track service life,maintenance costs and the general public of the ride experience and other factors,so the orbital state of the test is increasingly becoming a hot issue.The dynamic data processing method of 20-40km/h velocity data is studied in this paper,which is based on strapdown inertial navigation(INS)principle for track irregularity.Based on the research and development of the current domestic and overseas orbit detection equipment,the feasibility of strapdown inertial measurement technology in orbit detection is studied in depth.The method uses the principle of strapdown inertial measurement,uses the acceleration sensor to measure the triaxial acceleration in the inertial space of the portable small-scale track inspection vehicle,and then uses the angular acceleration data collected by the gyro sensor to update the attitude matrix constantly.The three-axis component is transformed into the navigation coordinate system through the updated attitude matrix,and finally the converted acceleration is integrated to obtain the movement state of the portable small-scale track inspection vehicle in the three-dimensional space so as to reflect the deformation of the measured rail orbit;Based on the principle of laser triangulation,the track gauge detection system realizes non-contact real-time detection of the change of track gauge,so as to detect the geometrical irregularity of the track state comprehensively.Finally,according to the data of the measuring system of shaft angle encoder,gauge measuring instrument,to correct andcompensate the inertial measurements derived data,improve the detection accuracy,in order to achieve practical needs.(1)This paper discusses the classification and detection methods of track irregularity,investigates the current development history and present situation of track inspection equipment at home and abroad,and puts forward the object and target of this subject according to the project demand.(2)The strapdown inertial measurement technology is introduced,the error model of SINS is designed,including velocity and position algorithm,velocity error and position error calculation model.To establish the calculation model of track geometry detection and3 D coordinates of track geometry,including gauge theory calculation,height and the track and ultra high(horizontal)geometry and track geometry of 3D coordinate position detection point,establishes the corresponding calculation model of track irregularity.(3)Aiming at the task requirement and parameter index of track irregularity detection system,the overall scheme of track inspection system is designed,which includes the mechanical design of car body of portable small track inspection vehicle,the selection of data acquisition sensor and the measurement data processing system.(4)A series of orbital detection tests were designed to evaluate the feasibility of the proposed method and the accuracy of the measurement by using the on-board sensor system.And by comparing the data of this test system with the measured data of the standard orbital scale,to analyze the reasonableness and error of the track irregularity measurement.The results show that the proposed detection method and technical scheme can play a good role in orbit detection.The orbital state detection system can be used to measure the track irregularity and can be used for further research and application.