Research On Track Irregular Low Speed Detection Technology

Track detection is an important means to master the geometry of the track in time,guide the maintenance of the work,and ensure the safe operation of the railway.In this paper,the theoretical reasons,algorithm flow and measured data analysis are carried out for the distortion of the track irregularity detection at low speed.The corresponding solution is proposed and the short-wave filter suitable for low-speed detection can be designed quickly.(1)In this paper,the physical model of the inertial reference method is established,and the transfer function of the inertial reference method is analyzed.The results show that the acceleration sensor on the mass mainly reflects the long-wave irregularity with lower frequency,while the relative displacement sensor between the mass and the base mainly reflects the high frequency shortwaves.The vibration equation is established for the inertial reference method,and the relationship between the input and output of the system under different external excitations of different parameters is analyzed.(2)The anti-aliasing filter with a fixed-time cutoff frequency is fixed in the time domain.The orbit detection system is equally spaced,so the spatial amplitude-frequency characteristics of the anti-aliasing filter are related to the velocity parameters.In this paper,the equations are established,and Taylor expansion is performed on the coefficients.The mathematical equations are used to solve the linear equations,and the corresponding compensation filters are designed.(3)Combined with the theory of inertial reference method,the high and low accelerometers,high and low displacement gauges,orbital accelerometers and orbital displacement gauges in the actual data of a pilot section of the Beijing-Shanghai Joint Commissioning Test are analyzed.The above inertial reference is verified by the spectrum calculation results of actual data.The analysis of the physical model of the law,and the reason for the distortion of the track irregularity and low speed detection results from the perspective of actual data.(4)Based on theoretical analysis and a large number of experiments,this paper proposes a new high-low and low-speed detection method,which is based on the gyroscope's orbital height and low-level detection.The test shows that the number of sensors required by this method is small,the system is simple,and the equipment Simple installation,which can effectively improve the distortion of low-speed detection results,is an efficient measurement method.(5)Combined with the above analysis and verification,this paper proposes a method based on the principle of inertial detection and using complementary filtering to fuse accelerometer and gyro measurement,and reduce the integral error under low speed detection by changing the integral method.Experiments verify that the above method can effectively reduce the distortion of the track irregularity and low speed detection results.(6)In this paper,the properties of common window functions and the spectrum of first-order and second-order components of cosine-like window functions are analyzed.The optimal window length grading design of second-order,third-order and fourth-order rectangular window cascades is completed,and the minimum two are used.The multiplication method completes the optimal matching of the rectangular window cascade base window length and cutoff frequency,and is designed to be suitable for the shortwave filter of track irregularity detection.