CN112762809B - Method for detecting gap fault of seamed steel rail - Google Patents
Method for detecting gap fault of seamed steel rail Download PDFInfo
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- CN112762809B CN112762809B CN202011636422.XA CN202011636422A CN112762809B CN 112762809 B CN112762809 B CN 112762809B CN 202011636422 A CN202011636422 A CN 202011636422A CN 112762809 B CN112762809 B CN 112762809B
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- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 53
- 239000010959 steel Substances 0.000 title claims abstract description 53
- 238000000034 method Methods 0.000 title claims abstract description 26
- 238000006073 displacement reaction Methods 0.000 claims abstract description 35
- 230000003595 spectral effect Effects 0.000 claims abstract description 4
- 230000001133 acceleration Effects 0.000 claims description 18
- 239000000523 sample Substances 0.000 claims description 11
- 238000000354 decomposition reaction Methods 0.000 claims description 7
- 230000004927 fusion Effects 0.000 claims description 6
- 238000007781 pre-processing Methods 0.000 claims description 5
- 238000005070 sampling Methods 0.000 claims description 5
- 238000006243 chemical reaction Methods 0.000 claims description 4
- 238000004891 communication Methods 0.000 claims description 4
- 238000007621 cluster analysis Methods 0.000 claims description 3
- 238000012937 correction Methods 0.000 claims description 3
- 238000012423 maintenance Methods 0.000 abstract description 4
- 238000001514 detection method Methods 0.000 description 7
- 238000005259 measurement Methods 0.000 description 6
- 238000000605 extraction Methods 0.000 description 3
- 230000035945 sensitivity Effects 0.000 description 3
- 238000011161 development Methods 0.000 description 2
- 230000007274 generation of a signal involved in cell-cell signaling Effects 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 238000011896 sensitive detection Methods 0.000 description 2
- 230000003044 adaptive effect Effects 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000003745 diagnosis Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B7/00—Measuring arrangements characterised by the use of electric or magnetic techniques
- G01B7/02—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring length, width or thickness
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B7/00—Measuring arrangements characterised by the use of electric or magnetic techniques
- G01B7/14—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring distance or clearance between spaced objects or spaced apertures
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
- G01H17/00—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves, not provided for in the preceding groups
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
- G01S19/38—Determining a navigation solution using signals transmitted by a satellite radio beacon positioning system
- G01S19/39—Determining a navigation solution using signals transmitted by a satellite radio beacon positioning system the satellite radio beacon positioning system transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
- G01S19/42—Determining position
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Computer Networks & Wireless Communication (AREA)
- Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)
- Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)
Abstract
The invention provides a method for detecting a crack fault of a seamed steel rail, which relates to the technical field of seamed steel rail maintenance and comprises the steps that an on-board computer obtains vibration signals of wheels in real time through a vibration detector, an eddy current displacement detector obtains the horizontal width and the vertical width of a steel rail crack, and an infrared receiver fixed on one side of the steel rail crack receives infrared rays emitted from a train and then feeds back the position information of the steel rail crack to the on-board computer through a positioning module; and identifying the fault type of the vibration signal by utilizing an LTSA algorithm and a spectral clustering method, judging whether the fault vibration is caused by the width of a gap by virtue of the detected width value of the gap of the steel rail if the generation reason of the vibration signal is identified to be the misalignment of the wheel, and if so, calculating the amount of the horizontal width value or the vertical width value exceeding a threshold value, and recording and outputting the amount in combination with the position coordinate. The problem of among the prior art artifical trouble accuracy and the timeliness of examining seam railway gap department poor is solved.
Description
Technical Field
The invention relates to the technical field of maintenance of seamed steel rails, in particular to a method for detecting seam fault of a seamed steel rail.
Background
Along with the continuous development of urban economy and society, the connection between cities is more and more intimate, and railway transportation is one of four transportation modes and has indispensable importance. The continuous progress of the seamless steel rail technology in recent years supports the vigorous development of high-speed railways in China. But the national railway business mileage reaches over 13.9 kilometers according to the data of the Chinese statistical office at the end of 2019; wherein, the business mileage of the high-speed railway is only 3.5 kilometers. A large number of seamed steel rails exist in the mileage of non-high speed railways, and particularly, the seamed steel rails cannot adapt to all road sections due to large four-season temperature change in northern areas of China, so the seamed steel rails are also strong pillars of railway career of China.
Due to the gaps between the steel rails, when a train passes through the gaps at a high speed, strong impact and vibration can be generated, so that not only can the smooth running of the train be influenced, but also the service life of the steel rails can be influenced, and particularly, the damage to the steel rails is serious for heavy-duty trains. The gap between the steel rails is enlarged or cracked, distorted or even broken due to impact and other reasons, most of the seamed railways in the prior art are railways built early, the maintenance of the railways also adopts a manual patrol inspection mode, the manual patrol cannot ensure the accuracy and timeliness, and when the damages are not found by railway maintainers in time for maintenance, serious accidents such as train derailment and the like are possibly caused.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides a method for detecting the fault of the gap of the seamed steel rail, which solves the problem that the accuracy and timeliness of the fault of the gap of the seamed railway are poor when the gap of the seamed railway is manually checked in the prior art.
In order to achieve the purpose of the invention, the technical scheme adopted by the invention is as follows:
the method for detecting the gap fault of the seamed steel rail comprises the following steps:
s1, in the running process of the train along the railway, the vehicle-mounted computer obtains vibration signals of wheels in real time through the vibration detector, obtains the horizontal width and the vertical width of a steel rail gap through the eddy current displacement detector, and feeds back the position information of the steel rail gap to the vehicle-mounted computer through the positioning module after the infrared receiver fixed on one side of the steel rail gap receives infrared rays emitted by the infrared emitter fixed on the train;
s2, preprocessing the vibration signal, performing feature fusion on the preprocessed vibration signal result by utilizing an LTSA algorithm, performing cluster analysis on the vibration signal subjected to feature fusion by utilizing a spectral clustering method, and identifying the fault type causing the vibration signal;
s3, if the vibration signal is identified to be caused by the misalignment of the wheels, acquiring the horizontal width value and the vertical width value of the steel rail gap at the same position, judging whether any one of the horizontal width value and the vertical width value exceeds a threshold value,
if so, calculating the amount of the horizontal width value or the vertical width value exceeding the threshold value, and recording and outputting the amount by combining the position coordinates;
if not, recording position coordinates and feeding back the position coordinates to a control center of the whole railway network, receiving feedback of all trains by the control center, and if the trains at the same position have the same feedback within a period of time, obtaining that a vibration signal generated by the misalignment of the wheel is generated by a steel rail crack at the position, otherwise, not generating the vibration signal.
The invention has the beneficial effects that: the crack steel rail gap fault detection method in the scheme is characterized in that an infrared receiver is arranged at each steel rail crack, and the infrared rays emitted by an infrared emitter on a running train are received by the infrared receiver and then fed back to the position information, so that the position information corresponds to the vibration condition of the wheels at the position and the steel rail crack width at the position, the vibration condition of the steel rail crack width and/or the wheels is excellent, fault points can be found quickly, and timeliness and accuracy are improved.
The accuracy of signal acquisition is improved by designing a system circuit and processing data of the system circuit by using an algorithm after the vibration signal and the displacement signal are acquired, so that the accuracy of fault detection is improved.
Detailed Description
The following description of the embodiments of the present invention is provided to facilitate the understanding of the present invention by those skilled in the art, but it should be understood that the present invention is not limited to the scope of the embodiments, and it will be apparent to those skilled in the art that various changes may be made without departing from the spirit and scope of the invention as defined and defined in the appended claims, and all matters produced by the invention using the inventive concept are protected.
The provided method for detecting the gap fault of the seamed steel rail comprises the following steps:
and S1, in the running process of the train along the railway, the vehicle-mounted computer obtains vibration signals of wheels in real time through the vibration detector, obtains the horizontal width and the vertical width of the steel rail gap through the eddy current displacement detector, and feeds back the position information of the steel rail gap to the vehicle-mounted computer through the positioning module after the infrared receiver fixed on one side of the steel rail gap receives infrared rays emitted by the infrared emitter fixed on the train.
The vibration detector collects vibration acceleration signals of the wheels, the conversion relation of the vibration acceleration is obtained through circuit conversion,
where, the reference is an acceleration signal, I is an AD sample value, and dx is a correction coefficient (here, dx is 1 by default).
Assuming that the number of sampling points is N, the acquired acceleration signal is { ak } (k is 1,2,3, …, N),
the acceleration signal obtained by equation (1) has white noise in addition to the dc component, and the dc component and the white noise must be removed before the acceleration signal is integrated, and the average value of the sampling points is calculated:
subtracting the average value from the acceleration value of each sampling point to obtain an acceleration signal a' k expression after the DC component is removed preliminarily:
a′k＝ak-a(k＝1，2，...，N)
according to the principle that the wavelet coefficient amplitude of the vibration signal is larger than the noise signal coefficient amplitude, the acceleration signal with the direct-current component removed is processed by using a wavelet threshold method so as to remove white noise. The unbiased likelihood estimation threshold, the fixed threshold, the heuristic threshold and the minimum maximum variance threshold are the most common methods for determining the threshold by the wavelet threshold denoising method. Different threshold law analyses are used on the acceleration signal to determine the optimal threshold law. In the scheme, a wavelet threshold denoising function is used, the selection of the threshold is determined by adopting a minimum maximum variance threshold and adjusting according to the noise level estimation of each layer of wavelet decomposition, and a better denoising effect can be obtained.
Carrying out n-layer decomposition on the denoised vibration signal, and respectively extracting 10 dimensionless characteristic parameters from each decomposition coefficient to form a fault characteristic set;
using DI[1]And measuring the sensitivities of 10 dimensionless characteristic parameters (NSPs) obtained by each decomposition coefficient in the fault characteristic set, and respectively selecting 2 characteristic parameters with stronger sensitivities to complete the preprocessing of the vibration signal.
And S2, performing feature fusion on the preprocessed vibration signal result by using an LTSA algorithm, performing cluster analysis on the vibration signal subjected to feature fusion by using a spectral clustering method, and identifying the fault type causing the vibration signal.
S3, if the vibration signal is identified to be caused by the misalignment of the wheels, acquiring the horizontal width value and the vertical width value of the steel rail gap at the same position, judging whether any one of the horizontal width value and the vertical width value exceeds a threshold value, judging whether the fault vibration is caused by the width of the gap by the detected steel rail gap width value,
if so, calculating the amount of the horizontal width value or the vertical width value exceeding the threshold value, and recording and outputting the amount by combining the position coordinates;
if not, recording position coordinates and feeding back the position coordinates to a control center of the whole railway network, receiving feedback of all trains by the control center, and if the trains at the same position have the same feedback within a period of time, obtaining that a vibration signal generated by the misalignment of the wheel is generated by a steel rail crack at the position, otherwise, not generating the vibration signal.
The detection system used in the method comprises an infrared transmitter, infrared receivers, a positioning module, a vibration detector and an eddy current displacement detection system, wherein the infrared receivers are arranged outside a steel rail gap along a railway and are connected with the positioning module and a wireless communication module; the infrared emitter is installed in train towards infrared receiver one side, and the vibration detector is installed on the train wheel, and current vortex displacement detecting system includes current vortex displacement detector and displacement measurement system, and current vortex displacement detector includes horizontal displacement probe and the vertical displacement probe of installing on the train through the support, and infrared emitter, vibration detector and current vortex displacement detecting system connect on the on-vehicle computer, on-vehicle computer and infrared receiver communication connection.
The system is arranged adjacent to a certain wheel of a train, only one infrared transmitter is arranged on each train in the process of train advancing, the infrared transmitter can continuously transmit infrared rays, only the place with a steel rail crack is provided with an infrared receiver, when the infrared receiver receives the infrared rays, the train is explained to move to the infrared receiver, and after the infrared receiver receives infrared signals, a microprocessor connected with the infrared receiver transmits the positioning information of a connected positioning module to an on-board computer of the train through wireless communication, so that the position information of the railway crack through which the train is provided with the infrared transmitter at the moment is obtained. Therefore, position coordinates are marked for continuous vibration signals and displacement signals, and fault points can be found quickly after faults are detected conveniently.
The horizontal displacement probe is located on the inner side of the horizontal direction of the steel rail gap, so that the width of the steel rail gap in the vertical direction can be detected as a vertical width value, and the vertical displacement probe is located above the steel rail gap and used for detecting the width of the steel rail gap in the length direction of the steel rail as a horizontal width value.
The eddy current displacement detection system comprises an eddy current displacement detector and a displacement measurement system, wherein the eddy current displacement detector is connected in the displacement measurement system, and the displacement measurement system comprises a signal generation module, a signal extraction module, a phase-sensitive detection module, a post-stage output module and a signal compensation module. The signal extraction module is used for converting the change of the displacement measured by the eddy current displacement detector into the change of voltage quantity and amplifying the change, the signal generation module is used for generating an excitation signal, the phase-sensitive detection module is used for demodulating the displacement signal and filtering an alternating current signal and then outputting a direct current signal, the post-stage output module is used for amplifying the output signal and improving the output sensitivity of the sensor, and the signal compensation module is used for carrying out nonlinear correction and temperature compensation on the displacement signal.
The displacement measurement system connected with the eddy current displacement detector utilizes an alternating current bridge method with higher resolution and system stability, a high-performance instrument amplifier and a high-precision low-temperature drift device to design a hardware circuit of the sensor displacement measurement system, carries out nonlinear compensation and temperature compensation on output signals, has the advantages of high precision, high stability, high reliability and strong anti-interference capability, and ensures that the measured steel rail gap change precision is higher and the fault detection is more accurate.
Reference to the literature
[1]Na Lu,Zhihuai Xiao,O.P.Malik,Feature extraction using adaptive multiwavelets and synthetic detection index for rotor fault diagnosis of rotating machinery[J],Mechanical Systems and Signal Processing.2015,52-53(201)393-415.
Claims (5)
1. A method for detecting a gap fault of a seamed steel rail is characterized by comprising the following steps:
s1, in the running process of the train along the railway, the vehicle-mounted computer obtains vibration signals of wheels in real time through the vibration detector, obtains the horizontal width and the vertical width of a steel rail gap through the eddy current displacement detector, and feeds back the position information of the steel rail gap to the vehicle-mounted computer through the positioning module after the infrared receiver fixed on one side of the steel rail gap receives infrared rays emitted by the infrared emitter fixed on the train;
s2, preprocessing the vibration signal, performing feature fusion on the preprocessed vibration signal result by utilizing an LTSA algorithm, performing cluster analysis on the vibration signal subjected to feature fusion by utilizing a spectral clustering method, and identifying the fault type causing the vibration signal;
s3, if the vibration signal is identified to be caused by the misalignment of the wheels, acquiring the horizontal width value and the vertical width value of the steel rail gap at the same position, judging whether any one of the horizontal width value and the vertical width value exceeds a threshold value,
if so, calculating the amount of the horizontal width value or the vertical width value exceeding the threshold value, and recording and outputting the amount by combining the position coordinates;
if not, recording position coordinates and feeding back the position coordinates to a control center of the whole railway network, receiving feedback of all trains by the control center, and if the trains at the same position have the same feedback within a period of time, obtaining that a vibration signal generated by the misalignment of the wheel is generated by a steel rail crack at the position, otherwise, not generating the vibration signal.
2. The method for detecting a gap fault of a seamed steel rail of claim 1, wherein the method for preprocessing the vibration signal comprises the following steps:
carrying out n-layer decomposition on the acquired vibration signals by using GHM multi-wavelets, and respectively extracting 10 NSPs from each decomposition coefficient to form a fault feature set;
the DI is used for measuring the sensibility of 10 NSPs obtained by each multi-wavelet decomposition coefficient in the fault characteristic set, and 2 characteristic parameters with stronger sensibility are respectively selected to complete the preprocessing of the vibration signal.
3. The method for detecting the gap fault of the seamed steel rail of claim 1, wherein the vibration detector collects vibration acceleration signals of the wheel, obtains a conversion relation of the vibration acceleration through circuit conversion,
in the formula accerFor acceleration signals, I is the AD sample value, dxIs a correction factor;
assuming that the number of sampling points is N, the acquired acceleration signal is { ak } (k is 1,2,3, …, N),
the acceleration signal obtained by equation (1) has white noise in addition to the dc component, and the dc component and the white noise must be removed before the acceleration signal is integrated, and the average value of the sampling points is calculated:
subtracting by acceleration value of each sample pointThe average value is removed, and the acceleration signal a 'with the DC component removed preliminarily can be obtained'kExpression:
a′k＝ak-a(k＝1，2，...，N)。
4. the method of claim 1, wherein the eddy current displacement sensor obtains the vertical width of the rail gap through a horizontal displacement probe, and the eddy current displacement sensor obtains the horizontal width through a vertical displacement probe, the horizontal displacement probe being located at the inner side of the rail gap in the horizontal direction, and the vertical displacement probe being located above the rail gap.
5. The method for detecting the gap fault of the seamed steel rail of claim 1, wherein the positioning module is a GPS module, and the infrared receiver, the wireless communication module and the positioning module are electrically connected with a single chip microcomputer.
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| JP5466385B2 (en) * | 2008-09-01 | 2014-04-09 | 公益財団法人鉄道総合技術研究所 | Rail clearance measurement device |
| CN101830237B (en) * | 2010-01-20 | 2011-11-30 | 黑龙江大学 | Safe and real-time detection system and method of heavy haulage lines based on optical fiber sensor network |
| CN102175768A (en) * | 2011-02-22 | 2011-09-07 | 哈尔滨工业大学 | Method and device for detecting defects and failures of high-speed rail based on vibration signals |
| CN103847761B (en) * | 2012-11-30 | 2016-06-29 | 建维科技（深圳）有限公司 | A kind of system and method for monitoring rail crack and damage in real time |
| CN106197332B (en) * | 2016-07-07 | 2019-01-18 | 四川金码科技有限公司 | The longitudinally displaced detection device of track seam and method |
| CN106394606B (en) * | 2016-11-10 | 2018-08-24 | 北京康拓红外技术股份有限公司 | A kind of railway car wheel loses circle detection method and detection device |
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