Research On Portable Track High And Low Irregular Detection System

In recent years,with the rapid development of railway trains and the rapid development of high-speed and heavy-duty railways,the dynamic role between railway vehicles and track structures has been increasing.The unevenness of the track has an increasingly strong influence on the comfort and safety of the train.The irregularity of the track may appear in the high,low,horizontal,orbital direction.The high and low irregularities are a form of rail damage and are widely found in the national railway.At present,the railway engineering section of China mainly uses static measurement methods such as track smoothness measuring instrument and track wave grinding rule for the detection of track irregularity.This method requires manual operation,low degree of automation and low efficiency,and there are still missed inspections.Therefore,it is important to study a set of orbital height and irregularity automatic measurement system that can be used with the track inspection vehicle.The main research work of this paper is as follows:1.Introduced the commonly used orbital high and low irregularity detection method.The principle of inertial reference method and string measurement method.The amplitude-frequency characteristics of the two-point string measurement method,the three-point string measurement method and the four-point string measurement method are analyzed in detail,and the range of the high and low unevenness recovery bands applicable to each method is pointed out.A wide-area high-level irregularity detection scheme combining four-point skew method and 10m string detection method is proposed.2.The measurement principle and error source of the bridge method are analyzed in detail.The chord length division ratio of the measurement scheme is determined based on the principle that the minimum error of the bridge method and the four-point skew method have a good transfer function.3.The improved Radha criterion is proposed to identify and repair the coarse error in the measured data.The empirical mode decomposition method(EMD)is used to remove the low-frequency trend term in the data,and the least square method is used to design the FIR inverse filter to track the height.The uneven waveform is restored,and the steps of designing the FIR inverse filter using the least squares method in the matlab environment are introduced4.The evaluation criteria of the track height and irregularity are put forward,and the measurement results are evaluated.In this paper,the measurement method and data processing method of orbital irregularity are studied,and a feasible orbital height and lowness measurement scheme is proposed.The detection system is designed from both hardware and software.Through the simulation experiment and the actual test,the detection accuracy of the 10m string and the accuracy of the short-band irregularity recovery of the detection system are verified.The maximum error of recovery in the 30-100mm,100-300mm,and 300-1000mm bands is 21μm,30p,m,33μm,and 66μm,respectively;the maximum error of the peak value of the 10m string detection is 1.27mm.The target indicators are basically satisfied.