A device for reconstructing the B-mode diagram of rail flaw detection

Abstract

The present invention discloses a B-mode diagram reconstruction device for rail flaw detection, which includes a coordinate unit calibration module. The coordinate unit calibration module further includes: a rail joint judgment unit, a wheel diameter ratio coefficient adjustment unit, and a rail length coordinate calibration unit. The rail joint judgment unit judges the rail joints according to the detected B-mode diagram. The rail length coordinate calibration unit calibrates the detected rail length by adjusting the wheel diameter ratio coefficient, and the value before adjustment is taken as 1. The wheel diameter ratio coefficient adjustment unit selects a standard-length rail according to the rail joints, calculates and determines the adjusted wheel diameter ratio coefficient. The rail length coordinate calibration unit takes the length of the rail corresponding to the measured encoder pulses as the calibrated rail length coordinate according to the adjusted wheel diameter ratio coefficient. The present invention can solve the technical problems that the parameters of the existing rail flaw detection vehicle need to be manually calibrated, the data of the detected B-mode diagram are not standardized, detection errors are likely to occur, and the damage recognition rate is not high.

Description

Technical Field

[0001] The present invention relates to the technical field of railway engineering machinery, and in particular to a detection B-mode diagram reconstruction device for a rail flaw detection vehicle, which is used to automatically calibrate and standardize the detection B-mode diagram and improve the damage recognition rate. Background Art

[0002] In the field of railway engineering and maintenance vehicles, ultrasonic rail flaw detection vehicles 50 are widely used for rail flaw detection and maintenance. As shown in the Figure 1 drawing, an ultrasonic rail flaw detection system generally includes: a rail flaw detection system 10 provided on the rail flaw detection vehicle, a rail flaw detection and analysis system 20, and a probe wheel 30 provided under the rail flaw detection vehicle. When rail flaw detection operation is required, the rail flaw detection vehicle controls the probe wheel 30 to press on the upper surface of the rail 40. The rail flaw detection system 10 sends an ultrasonic excitation pulse signal to the probe wheel 30. Under the action of an alternating electric field, the ultrasonic wafer of the probe wheel 30 generates a mechanical vibration synchronous with the electric field, thereby emitting an ultrasonic signal. This process is called the inverse piezoelectric effect. The ultrasonic wafer can also generate an alternating electric field when subjected to an alternating pressure, realizing the reception of ultrasonic echoes, which is called the direct piezoelectric effect. The principle of ultrasonic flaw detection applied in rail flaw detection is: according to the characteristics of ultrasonic waves, once encountering the surface of two different media, ultrasonic waves will be reflected, thus forming a certain ultrasonic echo signal. When ultrasonic waves enter the air from steel, 100% reflection will occur, so it has a good detection effect on rail defects.

[0003] As shown in the Figure 5 drawing, the probe wheel 30 usually adopts a wheel-type structure, and a plurality of groups of ultrasonic wafers 5 with different detection angles are installed on the axle center frame. The inner membrane of the tire of the probe wheel 30 is filled with a coupling liquid. When the rail flaw detection vehicle runs, the probe wheel 30 rolls along the rail 40, and the moving direction of the ultrasonic wafer 5 is parallel to the rail 40. When performing rail flaw detection operations, the ultrasonic signals emitted by the ultrasonic wafers of the probe wheel 30 are usually reflected at the contact surface between the probe wheel module 30 and the rail 40, the flaw surface in the rail 40, and the lower surface of the rail 40. The ultrasonic wafer of the probe wheel 30 receives the ultrasonic echo signal, and can further convert the acoustic signal into an electrical signal through the piezoelectric effect and transmit it to the rail flaw detection system 10. The rail flaw detection system 10 transmits the detection data to the rail flaw detection and analysis system 20 through Ethernet, and the rail flaw detection and analysis system 20 generates a rail damage detection B-mode diagram and conducts diagnostic analysis.

[0004] Ultrasonic waves are used for rail flaw detection, which mainly include the following characteristics: 1) Penetration: Ultrasonic waves can penetrate steel materials up to several meters thick; 2) Directivity: It has the property of linear propagation similar to light. The higher the frequency, the better the directivity, and it is easier to determine the location of defects; 3) Reflection characteristics: When ultrasonic waves encounter the surface of two different media during propagation, ultrasonic waves will be reflected, generating ultrasonic echo signals. When ultrasonic waves enter the air from steel, there will be 100% reflection, so it has a good detection effect on rail defects. When the defect size is larger than the ultrasonic wavelength, the ultrasonic waves will be reflected back from the defect surface. Rail flaw detection mainly forms A-scan display patterns and B-scan display patterns based on detection. During the detection process, water spraying coupling is required between the probe wheel and the rail surface to ensure that ultrasonic waves reach the rail. Due to the high speed of the locomotive, the coupling effect is not ideal. In addition, at the curved sections of the line, the probe wheel deviates from the center of the rail, resulting in many false alarms and missed detections. Damage identification still largely depends on manual identification, and there are many defects in automatic damage identification.

[0005] As shown in the Figure 1 attachment, the rail flaw detection system 10 is composed of ultrasonic wafers with up to more than 30 independent ultrasonic channels, so as to perform flaw detection on the rail 40 from multiple angles and directions. The detection system 10 is equipped with a probe wheel frame, which is symmetric left and right. Three probe wheels 30 are installed on each rail respectively. The probe wheel 30 adopts a wheel structure. The probe wheel frame is equipped with multiple groups of piezoelectric wafers with different detection angles, and the outer membrane of the probe wheel is filled with coupling liquid. When the rail flaw detection vehicle 50 is running, the probe wheel 30 rolls along the rail, and the moving direction of the wafer is parallel to the rail. The front and rear probe wheels are of the same type and are installed in opposite directions. There are 6 wafers in the probe wheel, namely a 0-degree, 37-degree, and 70-degree triple transducer array and a side-scan wafer; the middle probe wheel has two wafers with a 70-degree deviation angle pointing to the inner side of the rail and a 0-degree wafer.

[0006] The detection system 10 sends an excitation electrical signal to the piezoelectric wafer to generate ultrasonic waves. The ultrasonic wave signals are reflected at the contact surface between the probe wheel 30 and the rail 40, the flaw surface inside the rail 40, and the bottom surface of the rail 40. Then, through the piezoelectric effect of the wafer, the ultrasonic echo signal is converted into an electrical signal and transmitted to the rail flaw detection system 10. The detection system 10 transmits the wafer type and path transmission time parameters to the analysis system 20 through Ethernet. The analysis system 20 calculates the spatial position of the damage point based on the type, position, and path transmission time of the wafer, forms a rail ultrasonic B-scan display pattern, and the analysis system 20 automatically identifies the pattern and frames the damage with a yellow square, providing a modern detection means for rail maintenance.

[0007] An angle encoder is installed at the axle end of the wheel of the rail flaw detection vehicle. When the wheel travels one week, N pulses are generated. The B-scan pattern of the flaw detection uses the number of pulses as the X coordinate. When it becomes a length, it needs to be calculated according to the wheel diameter. Due to wheel wear, it is necessary to regularly measure and determine the wheel diameter ratio coefficient.

[0008] In the B-mode diagram, the fault feature points are defined according to the reflection surface of ultrasonic waves as shown in the appendix Figure 2 as shown. The normal direction of each fault feature point is the ultrasonic wave transmission direction. Each fault feature point can be detected by an ultrasonic piezoelectric wafer at a corresponding angle, corresponding to the detection channel number of the ultrasonic echo parameter data. As shown in the appendix Figure 4 as shown, it is a schematic diagram of the 37-degree rear piezoelectric wafer 1 detecting the rail bolt hole 2. According to the directivity of ultrasonic waves, ultrasonic waves propagate in a straight line within the detection range close to the wafer. Taking the rail surface as a reference, the conditions for ultrasonic echo signals are:

[0009]

[0010] where X and Y are the coordinates of the fault feature point A in the rail, a is the incident angle of ultrasonic waves in the rail 40, W is the width of the ultrasonic wafer, the rail flaw detection system 20 and the probe wheel 30 are both installed on the rail flaw detection vehicle 50, X1 is the running position of the rail flaw detection vehicle 50, and X2 is the relative coordinate of the ultrasonic wafer relative to the rail flaw detection vehicle 50.

[0011] The flaw detection B-mode diagram is obtained by detecting with multiple piezoelectric wafers at different positions. The results of the corresponding detection values need to be calculated according to the position of the piezoelectric wafer, that is, the space conversion parameters. To avoid measurement errors, manual calibration tests are required for debugging and setting. Summary of the Invention

[0012] In view of this, the purpose of the present invention is to provide a device for reconstructing the B-mode diagram of rail flaw detection, which automatically normalizes the data of the detected B-mode diagram to solve the technical problems that it is difficult to set the space conversion parameters in the manual calibration test, easy to make mistakes, and resulting in a low damage recognition rate of the B-mode diagram.

[0013] To achieve the above invention purpose, the present invention specifically provides a technical implementation scheme of a device for reconstructing the B-mode diagram of rail flaw detection. The device for reconstructing the B-mode diagram of rail flaw detection includes a coordinate unit calibration module, and the coordinate unit calibration module further includes: a rail joint judgment unit, a wheel diameter ratio coefficient adjustment unit, and a rail length coordinate calibration unit. The rail joint judgment unit judges the rail joint according to the detected B-mode diagram. The rail length coordinate calibration unit calibrates the length of the detected rail by adjusting the wheel diameter ratio coefficient k, and the k value is taken as 1 before adjustment. The wheel diameter ratio coefficient adjustment unit selects a standard length rail according to the rail joint, calculates and determines the adjusted wheel diameter ratio coefficient k. The rail length coordinate calibration unit takes the encoder pulse number n measured corresponding to the rail length according to the adjusted wheel diameter ratio coefficient k as the calibrated rail length coordinate.

[0014] Further, the rail joint judgment unit determines normal bolt holes based on the A-shaped feature map in the detected B-type diagram, and determines the rail joint based on the Y-shaped feature pattern. The bolt holes on both sides of the rail joint are symmetrically distributed and conform to the standard rail model dimensions.

[0015] Further, the detected B-type diagram uses the number of encoder pulses n installed at the axle end of the wheel set as the coordinate unit, and the rail length coordinate calibration unit calibrates the length S of the detected rail by adjusting the wheel diameter ratio coefficient k n Calibration: where π is the pi, and the wheel diameter ratio coefficient D0 is the standard wheel set diameter, D1 is the actual wheel set diameter, and N is the number of pulses output by the encoder when it rotates one week.

[0016] Further, the wheel diameter ratio coefficient adjustment unit selects a standard length rail without truncation according to the detected B-type diagram: according to the spacing of the rail joints, calculate the length of the rail as where D0 is the standard wheel set diameter, N is the number of pulses output by the corresponding encoder when it rotates one week, and n1 is the number of pulses corresponding to the measured rail. Let the length of the standard length rail be S, and δ1 be the rail wheel diameter error. When the length S1 of the detected rail satisfies (1 - δ1)S1 ≤ S ≤ (1 + δ1)S1, it is determined that the detected rail with length S1 is a standard length rail without truncation. Then select and calculate the length of another detected rail as where D0 is the standard wheel set diameter, N is the number of pulses output by the corresponding encoder when it rotates one week, and n2 is the number of pulses corresponding to the measured rail. When (1 - δ1)S2 ≤ S ≤ (1 + δ1)S2 is satisfied, it is determined that the detected rail with length S2 is a standard length rail without truncation. The relative error between the lengths of the two selected rails is within δ2, that is Then the wheel diameter ratio coefficient adjustment unit determines the wheel diameter ratio coefficient according to the average value of the encoder pulse numbers corresponding to the two measured rails

[0017] Further, the rail length coordinate calibration unit calculates the calibrated rail length coordinate S according to the wheel diameter ratio coefficient k determined by the wheel diameter ratio coefficient adjustment unit n :

[0018]

[0019] where n is the measured number of encoder pulses and k is the adjusted wheel diameter ratio coefficient.

[0020] Furthermore, the B-scan image reconstruction device for rail flaw detection further includes a spatial transformation parameter correction module. The spatial transformation parameters are determined by the positions of the wafers. The farthest point detected by the ultrasonic inspection of the rear wheel is defined as the reference point. The rear wheel is based on the center of the wheel axle. The distance between the rear wheel and the reference point is L, the distance between the center wheel and the rear wheel is L1, and the distance between the front wheel and the rear wheel is L2. The front and rear wheels are symmetrically installed. The distance between the 0-degree wafer and the wheel axle is l1, the distance between the 37-degree wafer and the wheel axle is l2, and the distance between the 70-degree wafer and the wheel axle is l3. The distance between the 0-degree wafer of the center wheel and the wheel axle is l4, the distance between the 70-degree wafer with a rear offset of the center wheel and the wheel axle is l5, and the distance between the 70-degree wafer with a front offset of the center wheel and the wheel axle is l6. The wheels are of a fixed structure and have been calibrated. The structural parameters l1 to l6 of the wheels are constant values. The spatial transformation parameter correction module calculates the wafer spatial transformation parameters according to the following formula:

[0021] 0-degree wafer of the rear wheel: L + l1;

[0022] 37-degree wafer of the rear wheel: L - l2;

[0023] 70-degree wafer of the rear wheel: L + l3;

[0024] 0-degree wafer of the center wheel: L + L1 + l4;

[0025] 70-degree wafer with a rear offset of the center wheel: L + L1 - l5;

[0026] 70-degree wafer with a front offset of the center wheel: L + L1 + l6;

[0027] 0-degree wafer of the front wheel: L + L2 - l1;

[0028] 37-degree wafer of the front wheel: L + L2 + l2;

[0029] 70-degree wafer of the front wheel: L + L2 - l3.

[0030] The rear wheel is selected as the reference, and the spatial transformation parameters of the rear wheel are not corrected. The spatial transformation parameter correction module selects the rail joint position of the detected B-scan image when the rail flaw detection vehicle runs at a low speed, calculates the difference ΔL2 between the 0-degree wafer detection patterns of the detected B-scan images of the front and rear wheels, and the spatial transformation parameter correction module calculates the corrected spatial transformation parameters of the front wheel according to the following formula:

[0031] 0-degree wafer of the front wheel: L + L2 + ΔL2 - l1;

[0032] 37-degree wafer of the front wheel: L + L2 + ΔL2 + l2;

[0033] 70-degree wafer of the front wheel: L + L2 + ΔL2 - l3.

[0034] S204) The space conversion parameter correction module calculates the distance difference ΔL1 between the center of the wafer detection pattern when the center detection wheel is deflected by 70 degrees and the center of the Y-shaped feature pattern according to the detected B-mode diagram. The space conversion parameter correction module calculates the corrected space conversion parameters of the center detection wheel according to the following formula:

[0035] Center detection wheel at 0-degree wafer: L + L1 + ΔL1 + l4;

[0036] Center detection wheel deflected 70 degrees backward: L + L1 + ΔL1 - l5;

[0037] Center detection wheel deflected 70 degrees forward: L + L1 + ΔL1 + L6.

[0038] Furthermore, the B-mode diagram reconstruction device for rail flaw detection further includes an amplitude filtering module. The detected B-mode diagram shows the positions of the detected damage points. The amplitude filtering module uses the A-mode display amplitude of the ultrasonic echo corresponding to the damage point as the display brightness of the corresponding detection point in the B-mode display.

[0039] Furthermore, the amplitude filtering module calculates the mean value A of the A-mode display amplitudes of the detection points in the same channel of the wafer at the bolt hole and the rail joint m , m is the wafer channel number. Manually adjust the amplitude filtering coefficient K, where 0 < K < 1, and KA m is used as the filtered amplitude. In the normal area where the detection wheel is centered, that is, when the centering deviation ΔS is within the allowable deviation δ3, ΔS ≤ δ3, the detection points below the filtered amplitude are not displayed, and a new detected B-mode diagram is generated. Manual-assisted flaw identification is performed based on the displayed pattern, and an appropriate amplitude filtering coefficient K is selected.

[0040] Furthermore, the B-mode diagram reconstruction device for rail flaw detection further includes a damage mirror image restoration module. The mirror image position of the detected B-mode diagram is determined by the coordinates of the rail joint. The ultrasonic wave emitted by the 37-degree wafer behind is reflected by the rail joint to detect the point P(x, y), forming a mirror image detection point P'(x', y'). The actual damage restores the point P according to the position of the point P'. Let the coordinates of the rail joint be x0, and θ be the angle of the 37-degree wafer behind. Then when the point P'(x', y') satisfies the condition 0 ≤ x' - x0 ≤ y'tagθ, the coordinates of the point P(x, y) restored by the mirror image restoration module are:

[0041]

[0042] Further, the ultrasonic waves emitted by the front 37-degree wafer are reflected by the rail joint to detect the point P'(x', y'), forming an image detection point P(x, y). The actual damage is restored to the point P' according to the position of the point P. Let the coordinate of the rail joint be x0, and θ be the angle of the front 37-degree wafer. Then when P(x, y) satisfies 0≥x - x0≥-y*tanθ, the coordinates of the point P'(x', y') restored by the image restoration module are:

[0043]

[0044] Further, the B-scan image reconstruction device for rail flaw detection further includes an out-of-alignment filtering module. When the probe wheel deviates from the rail at a curve on the line, an automatic alignment system is used to detect, control, and record the deviation value ΔS at the corresponding position of the detected B-scan image. When the probe wheel is out of alignment and the deviation value is greater than the set value δ4, and when the ultrasonic wave bottom echo of the rail from the 0-degree wafer is not lost, the out-of-alignment filtering module filters out the detection reflection points of the rail jaw part in the detected B-scan image to achieve out-of-alignment filtering. Let the height of the rail jaw from the rail surface be h, and the measurement error limit value be δ5. When y is the ordinate of the B-scan image, the out-of-alignment filtering module needs to satisfy the following three conditions simultaneously for out-of-alignment filtering:

[0045] ⅰ) The bottom echo is not lost;

[0046] ⅱ) ΔS>δ4;

[0047] ⅲ) h - δ5≤y≤h + δ5.

[0048] Further, the B-scan image reconstruction device for rail flaw detection further includes a detection channel missing warning module. When passing through the areas with rail joints and bolt holes, except for the side-scan channel, corresponding feature points are displayed in the detected B-scan image, and the missing part is displayed by the detection channel missing warning module to indicate the corresponding channel missing.

[0049] By implementing the technical solution of the B-scan image reconstruction device for rail flaw detection provided by the present invention, the following beneficial effects are achieved:

[0050] (1) The B-scan image reconstruction device for rail flaw detection of the present invention reconstructs the detected B-scan image data according to the rail model, standardizes the detection pattern, lays a foundation for computer damage recognition, improves the damage recognition efficiency, and reduces false alarms;

[0051] (2) The B-scan image reconstruction device for rail flaw detection of the present invention identifies the rail joint according to the detected B-scan image and automatically calibrates the wheel diameter according to the standard rail length, which can improve the detection accuracy and provide a means for accurate damage positioning and trend comparison analysis;

[0052] (3) The B-scan image reconstruction device for rail flaw detection of the present invention automatically calibrates the spatial parameters of the probe wafer of the rail flaw detection vehicle according to the actual detected B-scan image, which can effectively avoid errors and deviations caused by manual settings, improve the automation level of rail flaw detection, and reduce the dependence of the detection system on the operator's level;

[0053] (4) The B-scan image reconstruction device for rail flaw detection of the present invention uses the amplitude of the A-scan display as the brightness representation of the B-scan display, which is convenient for manual observation and analysis. By setting appropriate filtering amplitudes, detection interference points with small amplitudes can be removed;

[0054] (5) The B-scan image reconstruction device for rail flaw detection of the present invention uses the centering deviation for auxiliary judgment, which can effectively remove false alarms of damage in the rail jaw part, and at the same time can warn of the detection channel missing fault, reminding the operator to repair in time to ensure the integrity of the detection graph. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention, and those of ordinary skill in the art can also obtain other embodiments based on these drawings without creative efforts.

[0056] Figure 1 is the system structure block diagram of the flaw detection system of the rail flaw detection vehicle in the prior art;

[0057] Figure 2 is the definition schematic diagram of the fault feature points in the B-scan image of rail flaw detection;

[0058] Figure 3 is the schematic diagram of the "A"-shaped detection graph of the bolt hole in the B-scan image of rail flaw detection;

[0059] Figure 4 is the schematic diagram of the principle of using ultrasonic piezoelectric wafers to detect rail damage in the prior art;

[0060] Figure 5 is the schematic diagram of the ultrasonic piezoelectric wafer detection process in the prior art;

[0061] Figure 6 is the schematic diagram of the "Y"-shaped detection graph at the rail joint in the B-scan image of rail flaw detection;

[0062] Figure 7 is a typical B-scan image of rail joint detection in the prior art;

[0063] Figure 8 is the schematic diagram of the spatial conversion parameters of the B-scan image of rail flaw detection;

[0064] Figure 9 It is a schematic diagram of the dimensional structure of the cross-section of a steel rail in the prior art;

[0065] Figure 10 It is a schematic diagram of the dimensional structure of the side of the rail end in the prior art;

[0066] Figure 11 It is a schematic diagram of the principle of flaw mirror image restoration processing in a specific embodiment of the B-scan image reconstruction device for steel rail flaw detection of the present invention;

[0067] Figure 12 It is a schematic diagram of the principle of misalignment filtering processing in a specific embodiment of the B-scan image reconstruction device for steel rail flaw detection of the present invention;

[0068] Figure 13 It is a block diagram of the structural composition of the coordinate unit calibration module in a specific embodiment of the B-scan image reconstruction device for steel rail flaw detection of the present invention;

[0069] Figure 14 It is a block diagram of the spatial conversion parameter correction module in a specific embodiment of the B-scan image reconstruction device for steel rail flaw detection of the present invention;

[0070] Figure 15 It is a block diagram of the amplitude filtering module in a specific embodiment of the B-scan image reconstruction device for steel rail flaw detection of the present invention;

[0071] Figure 16 It is a block diagram of the flaw mirror image restoration module in a specific embodiment of the B-scan image reconstruction device for steel rail flaw detection of the present invention;

[0072] Figure 17 It is a block diagram of the misalignment filtering module in a specific embodiment of the B-scan image reconstruction device for steel rail flaw detection of the present invention;

[0073] Figure 18 It is a block diagram of the detection channel missing warning module in a specific embodiment of the B-scan image reconstruction device for steel rail flaw detection of the present invention;

[0074] Figure 19 It is a program flow chart of a specific embodiment of the B-scan image reconstruction method for steel rail flaw detection based on the device of the present invention;

[0075] In the figure: 1 - Coordinate unit calibration module, 2 - Spatial transformation parameter correction module, 3 - Amplitude filtering module, 4 - Damage mirror restoration module, 5 - Misalignment filtering module, 6 - Detection channel missing warning module, 10 - Rail flaw detection system, 11 - Rail joint judgment unit, 12 - Wheel diameter ratio coefficient adjustment unit, 13 - Rail length coordinate calibration unit, 20 - Rail flaw detection vehicle analysis system, 30 - Probe wheel, 40 - Rail, 50 - Rail flaw detection vehicle, 60 - Chip, 70 - Damage feature point, 80 - Bolt hole, 90 - Rail joint, 100 - Rail jaw detection reflection point. Detailed implementation manner

[0076] Number of mileage pulses: A rotary encoder is installed at the axle end of the locomotive wheel set. When a wheel with a wheel diameter of D rotates one week, the traveling distance is πD, corresponding to the number of pulses N output by the encoder when it rotates one week. Since the encoder has high precision and is used for the distance measurement of the flaw detection vehicle, the pulse interval (πD / N) is used as the basic unit for positioning.

[0077] A-scan display: The ultrasonic echo is displayed in the form of a waveform, with the vertical coordinate representing the amplitude of the reflected wave and the horizontal coordinate representing the transmission time of the wave.

[0078] B-scan display: The position of the damage is displayed in the form of an image.

[0079] Damage identification: In the B-scan diagram, the damage area is framed with a warning color (such as yellow).

[0080] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0081] As shown in the attached Figure 1 to the attached Figure 19 figures, specific embodiments of the B-scan diagram reconstruction device for rail flaw detection of the present invention are given. The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0082] Embodiment 1

[0083] As shown in the attached Figure 13As shown in the figure, an embodiment of a B-type diagram reconstruction device for rail flaw detection according to the present invention includes a coordinate unit calibration module 1, and the coordinate unit calibration module 1 further includes: a rail joint judgment unit 11, a wheel diameter ratio coefficient adjustment unit 12, and a rail length coordinate calibration unit 13. The rail joint judgment unit 11 judges the rail joint 90 according to the detected B-type diagram. The rail length coordinate calibration unit 13 calibrates the length of the detected rail 40 by adjusting the wheel diameter ratio coefficient k, and the value of k is taken as 1 before adjustment. The wheel diameter ratio coefficient adjustment unit 12 selects a standard length rail according to the rail joint 90, calculates and determines the adjusted wheel diameter ratio coefficient k. The rail length coordinate calibration unit 13 takes the encoder pulse number n measured corresponding to the rail 40 as the calibrated rail length coordinate according to the adjusted wheel diameter ratio coefficient k.

[0084] The rail joint judgment unit 11 judges normal bolt holes 80 according to the A-shaped feature diagram in the detected B-type diagram, and judges the rail joint 90 according to the Y-shaped feature diagram. The bolt holes 80 on both sides of the rail joint 90 are symmetrically distributed and conform to the standard rail model size.

[0085] The detected B-type diagram uses the encoder pulse number n installed at the axle end of the wheel pair as the coordinate unit. The rail length coordinate calibration unit 13 calibrates the length S of the detected rail 40 by adjusting the wheel diameter ratio coefficient k n Calibration: where π is the pi, and the wheel diameter ratio coefficient D0 is the standard wheel pair diameter, D1 is the actual wheel pair diameter, and N is the number of pulses output by the encoder when it rotates one week.

[0086] The wheel diameter ratio coefficient adjustment unit 12 selects a standard length rail without truncation according to the detected B-type diagram: according to the spacing of the rail joint 90, calculate the length of the rail 40 as where D0 is the standard wheel pair diameter, N is the number of pulses output by the corresponding encoder when it rotates one week, and n1 is the number of pulses corresponding to the measured rail. Let the length of the standard length rail be S, and δ1 be the rail wheel diameter error. When the length S1 of the detected rail 40 satisfies (1 - δ1)S1 ≤ S ≤ (1 + δ1)S1, it is determined that the detected rail 40 with length S1 is a standard length rail without truncation. Then select and calculate the length of another detected rail 40 as where D0 is the standard wheel pair diameter, N is the number of pulses output by the corresponding encoder when it rotates one week, and n2 is the number of pulses corresponding to the measured rail. When (1 - δ1)S2 ≤ S ≤ (1 + δ1)S2 is satisfied, it is determined that the detected rail 40 with length S2 is a standard length rail without truncation. The relative error between the lengths of the two selected rails is within δ2, that is Then the wheel diameter ratio coefficient adjustment unit 12 determines the wheel diameter ratio coefficient according to the average value of the encoder pulse numbers corresponding to the two measured rails

[0087] The rail length coordinate calibration unit 13 further calculates the calibrated rail length coordinate S according to the wheel diameter ratio coefficient k determined by the wheel diameter ratio coefficient adjustment unit 12 n :

[0088]

[0089] where n is the measured encoder pulse number and k is the adjusted wheel diameter ratio coefficient.

[0090] The probe wheels 30 of the rail flaw detector 50 include forward probe wheels, backward probe wheels and central probe wheels. As shown in the appendix Figure 14 The rail flaw detection B-mode diagram reconstruction device further includes a space conversion parameter correction module 2. The space conversion parameter is determined by the wafer position. The farthest point of ultrasonic detection of the rear probe wheel is defined as the reference point. The probe wheel 30 is based on the wheel axle center. The distance between the rear probe wheel and the reference point is L, the distance between the central probe wheel and the rear probe wheel is L1, and the distance between the forward probe wheel and the rear probe wheel is L2. The forward and backward probe wheels are symmetrically installed. The distance between the 0-degree wafer and the wheel axle is l1, the distance between the 37-degree wafer and the wheel axle is l2, and the distance between the 70-degree wafer and the wheel axle is l3. The distance between the 0-degree wafer of the central probe wheel and the wheel axle is l4, the distance between the 70-degree wafer with a rear offset of the central probe wheel and the wheel axle is l5, and the distance between the 70-degree wafer with a front offset of the central probe wheel and the wheel axle is l6. The probe wheel 30 is a fixed structure and has been calibrated. The structural parameters l1 to l6 of the probe wheel 30 are constant values. The space conversion parameter correction module 2 calculates the wafer space conversion parameters as follows:

[0091] 0-degree wafer of the rear probe wheel: L + l1;

[0092] 37-degree wafer of the rear probe wheel: L - l2;

[0093] 70-degree wafer of the rear probe wheel: L + l3;

[0094] 0-degree wafer of the central probe wheel: L + L1 + l4;

[0095] 70-degree wafer with a rear offset of the central probe wheel: L + L1 - l5;

[0096] 70-degree wafer with a front offset of the central probe wheel: L + L1 + l6;

[0097] 0-degree wafer of the forward probe wheel: L + L2 - l1;

[0098] 37-degree wafer of the forward probe wheel: L + L2 + l2;

[0099] 70-degree wafer of the forward probe wheel: L + L2 - l3.

[0100] Taking the rear detection wheel as the reference, the spatial conversion parameters of the rear detection wheel are not corrected. The spatial conversion parameter correction module 2 selects the detection B-scan image at the 90th rail joint when the rail flaw detection vehicle is running at a low speed, and the difference in the number of detection points of the 0-degree wafers of the front and rear detection wheels is ≤ 1. Since the detection wheel 30 has a fixed structure and has been calibrated, the structural parameters l1 to l6 of the detection wheel 30 are constant values.

[0101] Based on the detection B-scan image, the spatial conversion parameter correction module 2 calculates the difference ΔL2 in the detection patterns of the 0-degree wafers of the detection B-scan images of the front and rear detection wheels. The spatial conversion parameter correction module 2 calculates and outputs the corrected spatial conversion parameters of the front detection wheel according to the following formula:

[0102] For the 0-degree wafer of the front detection wheel: L + L2 + ΔL2 - l1;

[0103] For the 37-degree wafer of the front detection wheel: L + L2 + ΔL2 + l2;

[0104] For the 70-degree wafer of the front detection wheel: L + L2 + ΔL2 - l3.

[0105] Based on the detection B-scan image, the spatial conversion parameter correction module 2 calculates the difference ΔL1 between the center distance of the detection pattern of the 70-degree wafer when the center detection wheel is deflected and the center of the Y-shaped feature point pattern. The spatial conversion parameter correction module 2 calculates and outputs the corrected spatial conversion parameters of the center detection wheel according to the following formula:

[0106] For the 0-degree wafer of the center detection wheel: L + L1 + ΔL1 + l4;

[0107] For the rear-deflected 70-degree wafer of the center detection wheel: L + L1 + ΔL1 - l5;

[0108] For the front-deflected 70-degree wafer of the center detection wheel: L + L1 + ΔL1 + L6.

[0109] As shown Figure 15 in the appendix, the rail flaw detection B-scan image reconstruction device further includes an amplitude filtering module 5. The detection B-scan image shows the positions of the detected damage points. The amplitude filtering module 5 uses the A-scan amplitude corresponding to the ultrasonic echo size of the damage point as the display brightness signal of the corresponding detection point in the B-scan display.

[0110] The amplitude filtering module 3 calculates the average value A of the A-scan amplitudes of the same-channel detection points of the wafer 60 at the bolt hole 80 and the rail joint 90 m , where m is the wafer channel number. Manually adjust the amplitude filtering coefficient K, where 0 < K < 1, and KA m is used as the filtering amplitude. In the normal area of the alignment of the detection wheels 30, that is, when the alignment deviation ΔS is within the allowable deviation δ3, ΔS ≤ δ3, the detection points below the filtering amplitude are not displayed, and a new detection B-scan image is generated. Manual-assisted damage identification is performed based on the displayed image, and an appropriate amplitude filtering coefficient K is selected.

[0111] As shown in the attached Figure 16 figure, the B-scan image reconstruction device for rail flaw detection further includes a damage mirror image restoration module 4. The mirror image position of the detected B-scan image is determined by the coordinates of the rail joint 90. The ultrasonic wave emitted by the rear 37-degree chip is reflected by the rail joint 90 to detect a point P(x, y). The point P is located in the detection blind area of the front 37-degree chip, that is, the ΔABC area, and a mirror image detection point P'(x', y') is formed. The actual damage restores the point P according to the position of the point P'. Let the coordinates of the rail joint 90 be x0, and θ be the angle of the rear 37-degree chip. Then when the point P'(x', y') satisfies the condition 0 ≤ x' - x0 ≤ y'tanθ, the coordinates of the point P(x, y) restored by the mirror image restoration module 4 are:

[0112]

[0113] The ultrasonic wave emitted by the front 37-degree chip is reflected by the rail joint 90 to detect a point P'(x', y'). The point P' is located in the detection blind area of the rear 37-degree chip, that is, the ΔABD area, and a mirror image detection point P(x, y) is formed. The actual damage restores the point P' according to the position of the point P. Let the coordinates of the rail joint 90 be x0, and θ be the angle of the front 37-degree chip. Then when P(x, y) satisfies 0 ≥ x - x0 ≥ -ytanθ, the coordinates of the point P'(x', y') restored by the mirror image restoration module 4 are:

[0114]

[0115] As shown in the attached Figure 17 figure, the B-scan image reconstruction device for rail flaw detection further includes an off-center filtering module 5. When the probe wheel 30 deviates from the rail 40 at a line curve, an automatic centering system is used to detect, control, and record the deviation value ΔS at the corresponding position of the detected B-scan image. When the probe wheel 30 is off-center and the deviation value is greater than the set value δ4, and when the ultrasonic wave bottom echo of the rail from the 0-degree chip does not disappear, the off-center filtering module 5 filters out the detection reflection points 100 of the rail jaw part of the rail 40 in the detected B-scan image to achieve off-center filtering. Let the height of the rail jaw from the rail surface be h, and the measurement error limit value be δ5. When y is the vertical coordinate of the B-scan image, the off-center filtering module 5 needs to simultaneously meet the following three conditions for off-center filtering:

[0116] ⅰ) The bottom echo has not disappeared;

[0117] ⅱ) ΔS > δ4;

[0118] ⅲ) h - δ5 ≤ y ≤ h + δ5.

[0119] As shown in the attached Figure 18As shown, the B-scan image reconstruction device for rail flaw detection further includes a detection channel missing warning module 6. When passing through areas with rail joints 90 and bolt holes 80, except for the side-scan channel, corresponding feature points are displayed in the detection B-scan image, and the missing part is indicated by the detection channel missing warning module 6 to show the corresponding channel missing.

[0120] Embodiment 2

[0121] As shown in the attached Figure 19 figure, an embodiment of a B-scan image reconstruction device for rail flaw detection based on the method described in Embodiment 1 includes at least one (i.e., one or more than two) processing processes for the B-scan image of rail flaw detection as follows:

[0122] S1) Calibrate the coordinate unit of the detection B-scan image according to the rail model;

[0123] S2) Correct the spatial conversion parameters of the probe wheel chip according to the detection B-scan image data of the rail joint 90;

[0124] S3) Use the amplitude of the A-scan display as the brightness display of the detection B-scan image for manual selection of an appropriate display amplitude and perform amplitude filtering processing to filter out interference detection points with inappropriate detection amplitude settings;

[0125] S4) Restore the position of the damage mirror image generated at the rail joint 90 to avoid false alarms of the damage position;

[0126] S5) Filter out the rail jaw detection points according to the record of the probe wheel centering deviation to eliminate false alarms of damage;

[0127] S6) Warn of the missing detection channel according to the detection B-scan image data at the rail joint 90.

[0128] Process S1) further includes the following steps:

[0129] S101) Judge the rail joint 90 according to the detection B-scan image;

[0130] S102) Calibrate the length of the detected rail 40 by adjusting the wheel diameter ratio coefficient k, and the k value is taken as 1 before adjustment;

[0131] S103) Select a standard-length rail according to the rail joint 90, calculate and determine the adjusted wheel diameter ratio coefficient k;

[0132] S104) Take the length of the rail corresponding to the measured encoder pulse number n as the calibrated rail length coordinate according to the adjusted wheel diameter ratio coefficient k.

[0133] Step S101) further includes:

[0134] Based on the A-shaped feature map in the detection B-type diagram data, the normal bolt holes 80 are judged, and the rail joint 90 is judged according to the Y-shaped feature map. The bolt holes 80 on both sides of the rail joint 90 are symmetrically distributed and conform to the standard rail model size, as shown in the appendix Figure 9 As shown. Automatically calibrating the wheel diameter according to the standard length rail model can improve the measurement accuracy of the detection B-type diagram and provide an effective means for accurate positioning of damages and trend comparison analysis.

[0135] A rotary encoder is installed at the axle end of the wheels of the rail flaw detector 50. Let the standard wheel diameter be D0, then the distance traveled by the wheel set in one revolution is πD0, and the number of pulses output by the encoder in one revolution is N. Since the rotary encoder has high precision and is used for the distance detection of the rail flaw detector 50, this number of pulses is used as the coordinate measurement unit of the detection B-type diagram, and the corresponding spacing is πD0 / N. Let the number of pulses for measuring the standard rail when setting the standard wheel diameter be n0, and the standard rail length be S. After the rail flaw detector 50 runs for a period of time, the tread of the wheel hub will wear. D1 is the wheel diameter of the worn wheel, and the number of pulses corresponding to the measured standard length rail is n1. Then:

[0136]

[0137] Let k be the wheel diameter ratio coefficient, representing the change in the wheel diameter, and should meet the requirements of operation management error, and the error is δ1.

[0138] Step S102) further includes:

[0139] The detection B-type diagram uses the number of pulses n of the encoder installed at the axle end of the wheel set as the coordinate unit, and calibrates the length S of the detected rail 40 by adjusting the wheel diameter ratio coefficient k: n Calibration: where, π is the pi, the wheel diameter ratio coefficient D0 is the standard wheel set diameter, D1 is the actual wheel set diameter, and N is the number of pulses output by the encoder in one revolution.

[0140] Step S103) further includes:

[0141] Select the standard length rail without truncation according to the detection B-type diagram: According to the spacing of the rail joint 90, calculate the length of the rail 40 as where, D0 is the standard wheel set diameter, N is the number of pulses output by the corresponding encoder in one revolution, and n1 is the number of pulses corresponding to the measured rail. Let the length of the standard length rail be S, and δ1 is the rail wheel diameter error. When the length S1 of the detected rail 40 satisfies (1 - δ1)S1 ≤ S ≤ (1 + δ1)S1, it is determined that the detected rail 40 with length S1 is a standard length rail without truncation. Then select and calculate the length of another detected rail 40 as Among them, D0 is the standard wheel diameter, N is the number of pulses output by the corresponding encoder for one revolution, and n2 is the number of pulses corresponding to the measured rail. When (1 - δ1)S2 ≤ S ≤ (1 + δ1)S2 is satisfied, it is determined that the detected rail 40 with a length of S2 is a standard-length rail without truncation. The relative error between the lengths of the two rails is within δ2, that is Then the wheel diameter proportionality coefficient k is determined by the average value of the encoder pulse numbers corresponding to the two measured rails:

[0142] In step S104), substitute the k value obtained in step S103) into the following formula in step S102) to determine the calibrated rail length coordinate S n :

[0143]

[0144] Among them, n is the measured encoder pulse number, and k is the adjusted wheel diameter proportionality coefficient.

[0145] The flaw detection system uses multiple detections. A fault feature point 70 can be detected multiple times. The fault feature points A, B, and C of the bolt hole 80 can be detected by different (piezoelectric) wafers 60, thus forming a detection pattern in the shape of an "A" as shown in the appendix Figure 3 As shown. Among them, there is no bottom reflection of the rail at the bolt hole for the 0-degree ultrasonic wave, forming a missing bottom wave.

[0146] As shown in the appendix Figure 6 As shown, there is a fixed detection pattern at the rail joint 90. At the perpendicular intersection of the rail joint 90 and the rail jaw surface, ultrasonic wave L1 can be reflected to form a joint pattern. In addition, ultrasonic wave L2 is reflected by the rail joint 90, and the wave type is converted from longitudinal wave to transverse wave to detect the bolt hole 80. Since the transverse wave sound velocity (3230 m / s) is much smaller than the longitudinal wave sound velocity (5860 m / s), the displayed distance of the detection point is shorter than the actual distance, forming a corner of the "Y" character feature map.

[0147] A typical B-mode diagram for rail joint detection is shown in the appendix Figure 7 As shown. Currently, the rail 40 mainly has five types listed in Table 1. The rail height can be measured using 0-degree ultrasonic waves to determine the type of the rail 40 and obtain the corresponding model parameters, as shown in the appendix Figure 9 and the appendix Figure 10 As shown. The centering record file uses the same coordinates as the B-mode diagram, and records are made every 1 mm change in deviation.

[0148]

[0149] Table 1 Rail type names and main dimensions

[0150] The rail flaw detection vehicle 50 performs inspections through multiple (piezoelectric) wafers 60 at different positions. When their positions deviate, the detected B-scan images also show corresponding deviations and variations, thus affecting the automatic identification of rail damages. The detection wheels 30 of the rail flaw detection vehicle 50 include forward detection wheels, backward detection wheels, and central detection wheels. Since the detection wheels 30 use constant pressure control for the downward pressure and monitor the ultrasonic A-scan of the 0-degree wafers of the detection wheels 30, it can be considered that there is no deviation in the Y-axis direction, and the spatial conversion parameters only need to be adjusted for the X-axis direction parameters.

[0151] As shown in the Figure 8 appendix, step S2) further includes the following steps:

[0152] S201) The spatial conversion parameters are determined by the wafer positions. Define the farthest point detected by the ultrasonic waves of the backward detection wheel as the reference point. With the center of the wheel axle as the reference for the detection wheel 30, the distance from the backward detection wheel to the reference point is L, the distance from the central detection wheel to the backward detection wheel is L1, and the distance from the forward detection wheel to the backward detection wheel is L2. The forward and backward detection wheels are symmetrically installed. The distance from the 0-degree wafer to the wheel axle is l1, the distance from the 37-degree wafer to the wheel axle is l2, and the distance from the 70-degree wafer to the wheel axle is l3. The distance from the 0-degree wafer of the central detection wheel to the wheel axle is l4, the distance from the 70-degree backward-biased wafer of the central detection wheel to the wheel axle is l5, and the distance from the 70-degree forward-biased wafer of the central detection wheel to the wheel axle is l6. The spatial conversion parameters of the wafers are:

[0153] 0-degree wafer of the backward detection wheel: L + l1;

[0154] 37-degree wafer of the backward detection wheel: L - l2;

[0155] 70-degree wafer of the backward detection wheel: L + l3;

[0156] 0-degree wafer of the central detection wheel: L + L1 + l4;

[0157] 70-degree backward-biased wafer of the central detection wheel: L + L1 - l5;

[0158] 70-degree forward-biased wafer of the central detection wheel: L + L1 + l6;

[0159] 0-degree wafer of the forward detection wheel: L + L2 - l1;

[0160] 37-degree wafer of the forward detection wheel: L + L2 + l2;

[0161] 70-degree wafer of the forward detection wheel: L + L2 - l3;

[0162] The detection wheel 30 has a fixed structure and has been calibrated. The structural parameters l1 to l6 of the detection wheel 30 are constant values.

[0163] S202) Select the backward detection wheel as the reference, and do not correct the spatial conversion parameters of the backward detection wheel;

[0164] S203) Select the position of the rail joint 90 in the detected B-scan image when the rail flaw detector runs at a low speed, and calculate the difference ΔL2 between the detected B-scan images of the 0-degree wafers of the front and rear detection wheels. Then, the corrected spatial conversion parameter of the front detection wheel is as follows:

[0165] For the 0-degree wafer of the front detection wheel: L + L2 + ΔL2 - l1;

[0166] For the 37-degree wafer of the front detection wheel: L + L2 + ΔL2 + l2;

[0167] For the 70-degree wafer of the front detection wheel: L + L2 + ΔL2 - l3.

[0168] S204) According to the detected B-scan image, calculate the difference ΔL1 between the center distance of the detected pattern of the 70-degree wafer of the center detection wheel deflected and the center of the Y-shaped characteristic pattern. Then, the corrected spatial conversion parameter of the center detection wheel is as follows:

[0169] For the 0-degree wafer of the center detection wheel: L + L1 + ΔL1 + l4;

[0170] For the 70-degree wafer deflected backward of the center detection wheel: L + L1 + ΔL1 - l5;

[0171] For the 70-degree wafer deflected forward of the center detection wheel: L + L1 + ΔL1 + L6.

[0172] In Example 1, according to the actual detected B-scan image, the spatial parameters of the detection wheels of the rail flaw detector 50 are automatically adjusted, avoiding errors and deviations caused by manual setting, improving the automation level of rail flaw detection, and reducing the dependence of the detection system on the operator's level.

[0173] Process S3) further includes the following steps:

[0174] S301) The detected B-scan image shows the position of the detected damage point, and the A-scan amplitude corresponding to the ultrasonic echo size of the damage point is used as the display brightness of the corresponding detection point in the B-scan display.

[0175] Step S301) further includes:

[0176] Calculate the mean value A of the A-scan amplitudes of the detection points of the same channel of the wafer 60 at the bolt hole 80 and the rail joint 90, m , where m is the wafer channel number, manually adjust the amplitude filtering coefficient K, and take 0 < K < 1, KA m as the filtered amplitude. In the normal area of the 30 pairs of detection wheels, that is, when the alignment deviation ΔS is within the allowable deviation δ3, ΔS ≤ δ3, the detection points lower than the filtered amplitude are not displayed, and a new detected B-scan image is generated. Artificial-assisted damage identification is performed according to the displayed image, and a suitable amplitude filtering coefficient K is selected.

[0177] The rail joint 90 will produce a specular reflection on the ultrasonic wave, causing an image of damage to occur in the nearby bolt hole 80, thereby causing misalignment in damage identification. As shown in the appendix Figure 11 The process S4) further includes the following steps:

[0178] S401) The mirror image position of the B-scan is detected and determined by the coordinates of the rail joint 90. The ultrasonic wave emitted by the 37-degree rear wafer is reflected by the rail joint 90 to detect the point P(x, y), thereby forming the mirror image detection point P'(x', y'). The actual damage restores the point P according to the position of the point P'. Let the coordinates of the rail joint 90 be x0, and θ be the angle of the 37-degree rear wafer. Then when the point P'(x', y') satisfies the condition 0 ≤ x' - x0 ≤ y'tanθ, the coordinates of the mirror image restoration point P(x, y) are:

[0179]

[0180] The process S4) further includes the following steps:

[0181] S402) The ultrasonic wave emitted by the 37-degree front wafer is reflected by the rail joint 90 to detect the point P'(x', y'), thereby forming the mirror image detection point P(x, y). The actual damage restores the point P' according to the position of the point P. Let the coordinates of the rail joint 90 be x0, and θ be the angle of the 37-degree front wafer. Then when P(x, y) satisfies 0 ≥ x - x0 ≥ -ytanθ, the coordinates of the mirror image restoration point P'(x', y') are:

[0182]

[0183] In Embodiment 1, by reconstructing the detected B-scan of the damage image caused by the rail joint 90, the damage detection pattern can be standardized, avoiding mispositioning of damage, helping to improve the automatic damage recognition rate, and helping to achieve trend quantitative analysis through multiple detections of damage, which is more intuitive than manual recognition.

[0184] The process S5) further includes the following steps:

[0185] When the probe wheel 30 deviates from the rail 40 at a curve on the line, the automatic centering system is used to detect, control, and record the deviation value ΔS at the corresponding position of the detected B-scan. When the probe wheel 30 is not centered and the deviation value is greater than the set value δ4, and when the ultrasonic wave bottom echo of the rail at the 0-degree wafer does not disappear, the detection reflection points 100 of the rail jaw part of the rail 40 are filtered out in the detected B-scan to achieve non-centering filtering. Let the height of the rail jaw from the rail surface be h, and the measurement error limit value be δ5. When y is the vertical coordinate of the B-scan, the non-centering filtering needs to simultaneously meet the following three conditions:

[0186] ⅰ) The bottom echo has not disappeared;

[0187] ii) ΔS > δ4;

[0188] iii) h - δ5 ≤ y ≤ h + δ5.

[0189] By using the centering deviation for auxiliary judgment, false alarms of damages in the web part of the 40 - rail can be effectively removed.

[0190] Process S6) further includes the following steps:

[0191] When passing through the areas of the rail joint 90 and the bolt hole 80, except for the side - hitting channels, corresponding feature points are shown in all inspection B - type diagrams, and the missing parts show the corresponding channel losses. Warning of the inspection channel loss fault can remind the operator to repair in time, thus ensuring the integrity of the inspection pattern and the reliability of the system operation.

[0192] In the description of the present application, it should be noted that when an element is referred to as "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly disposed on the other element; when an element is referred to as "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0193] It should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present application.

[0194] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, "a plurality of" and "several" mean two or more, unless otherwise specifically defined.

[0195] It should be noted that the structures, ratios, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those skilled in this technology to understand and read, and are not used to limit the implementable conditions of the present application. Therefore, they do not have a technical essence. Any modification of the structure, change of the ratio relationship or adjustment of the size, without affecting the effects that the present application can produce and the purposes that can be achieved, should still fall within the scope that the technical content disclosed in the present application can cover.

[0196] By implementing the technical solution of the B-scan image reconstruction device for rail flaw detection described in the specific embodiments of the present invention, the following technical effects can be achieved:

[0197] (1) The B-scan image reconstruction device for rail flaw detection described in the specific embodiments of the present invention standardizes the detection images through the reconstruction of the B-scan image data, laying a foundation for computer damage recognition and improving the damage recognition efficiency.

[0198] (2) The B-scan image reconstruction device for rail flaw detection described in the specific embodiments of the present invention identifies the rail joints based on the B-scan images and automatically calibrates the wheel diameter according to the standard rail length, which can improve the detection accuracy and provide a means for accurate damage positioning and trend comparison analysis.

[0199] (3) The B-scan image reconstruction device for rail flaw detection described in the specific embodiments of the present invention automatically adjusts the spatial parameters of the detection wheels of the rail flaw detection vehicle according to the actual B-scan images, which can effectively avoid errors and deviations caused by manual settings, improve the automation level of rail flaw detection, and reduce the dependence of the detection system on the operator's level.

[0200] (4) The B-scan image reconstruction device for rail flaw detection described in the specific embodiments of the present invention uses the amplitude of the A-scan as the brightness representation of the B-scan, which is convenient for manual observation and analysis. By setting appropriate filtering amplitudes, detection interference points with small amplitudes can be removed.

[0201] (5) The B-scan image reconstruction device for rail flaw detection described in the specific embodiments of the present invention uses the centering deviation for auxiliary judgment, which can effectively remove false alarms of damage in the rail web part, and at the same time can warn of the detection channel missing fault, reminding the operator to repair in time to ensure the integrity of the detection images.

[0202] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The same or similar parts among the various embodiments can be referred to each other.

[0203] The above is only a preferred embodiment of the present invention, and it is not intended to limit the present invention in any form. Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make many possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above, or modify it into equivalent embodiments with equivalent changes. Therefore, any simple modification, equivalent replacement, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the technical solution of the present invention still fall within the scope of the protection of the technical solution of the present invention.

Claims

1. A device for reconstructing the B-mode diagram of rail flaw detection, characterized in that, It includes a coordinate unit calibration module (1), and the coordinate unit calibration module (1) further includes: a rail joint judgment unit (11), a wheel diameter proportionality coefficient adjustment unit (12), and a rail length coordinate calibration unit (13); the rail joint judgment unit (11) judges the rail joint (90) according to the detected B-type diagram; the rail length coordinate calibration unit (13) calibrates the length of the detected rail (40) by adjusting the wheel diameter proportionality coefficient and the value before adjustment is taken as 1; the wheel diameter proportionality coefficient adjustment unit (12) selects a standard length rail according to the rail joint (90), calculates and determines the adjusted wheel diameter proportionality coefficient ; the rail length coordinate calibration unit (13) takes the number of encoder pulses measured corresponding to the length of the rail (40) as the calibrated rail length coordinate according to the adjusted wheel diameter proportionality coefficient ; the detected B-type diagram uses the number of encoder pulses installed at the axle end of the wheel set as the coordinate unit, and the rail length coordinate calibration unit (13) calibrates the length of the detected rail (40) by adjusting the wheel diameter proportionality coefficient : ; where ; is the pi, the wheel diameter proportionality coefficient , is the standard wheel set diameter, is the actual wheel set diameter, is the number of pulses output when the encoder rotates one week; the wheel diameter proportionality coefficient adjustment unit (12) selects a standard length rail without truncation according to the detected B-type diagram: calculates the length of the rail (40) according to the spacing of the rail joint (90) as ; where is the standard wheel set diameter, is the number of pulses corresponding to one rotation of the encoder, is the number of pulses corresponding to the measured rail; let the length of the standard length rail be , is the rail wheel diameter error, when the length of the detected rail (40) satisfies , it is determined that the detected rail (40) with length is a standard length rail without truncation; then select and calculate the length of another detected rail (40) as , where is the standard wheel set diameter, is the number of pulses corresponding to one rotation of the encoder, is the number of pulses corresponding to the measured rail; when is satisfied, it is determined that the length The detected rail (40) is a standard-length rail without truncation; the relative error between the lengths of the two selected rails is within i.e., Then, the wheel diameter ratio coefficient adjustment unit (12) determines the wheel diameter ratio coefficient according to the average value of the encoder pulses corresponding to the two measured rails ; The rail length coordinate calibration unit (13) calculates the calibrated rail length coordinate according to the wheel diameter ratio coefficient determined by the wheel diameter ratio coefficient adjustment unit (12) : ​ ； Among them, is the measured encoder pulse count, is the adjusted wheel diameter ratio coefficient.

2. The rail flaw detection B-type diagram reconstruction device according to claim 1, wherein: The rail joint judgment unit (11) judges normal bolt holes (80) according to the A-shaped feature pattern in the detected B-scan image, and judges the rail joint (90) according to the Y-shaped feature pattern; the bolt holes (80) on the left and right sides of the rail joint (90) are symmetrically distributed and conform to the standard rail model size.

3. The rail flaw detection B-type diagram reconstruction device according to claim 2, wherein: The device further includes a spatial conversion parameter correction module (2). The spatial conversion parameters are determined by the wafer position. The furthest point detected by the rear probe wheel ultrasonic is defined as the reference point. With the center of the wheel axis as the reference for the probe wheel (30), the distance from the rear probe wheel to the reference point is , the distance from the center probe wheel to the rear probe wheel is , and the distance from the front probe wheel to the rear probe wheel is ; The front and rear probe wheels are symmetrically installed. The distance from the 0-degree wafer to the wheel axis is , the distance from the 37-degree wafer to the wheel axis is , and the distance from the 70-degree wafer to the wheel axis is ; The distance from the 0-degree wafer of the center probe wheel to the wheel axis is , the distance from the 70-degree wafer with a 70-degree rear offset of the center probe wheel to the wheel axis is , and the distance from the 70-degree wafer with a 70-degree front offset of the center probe wheel to the wheel axis is ; The probe wheel (30) has a fixed structure and has been calibrated. The structural parameters of the probe wheel (30) are constant values; The spatial conversion parameter correction module (2) calculates the wafer spatial conversion parameters according to the following formula: Rear exploration wheel 0-degree wafer: ; Rear detection wheel 37-degree wafer: ; Rear exploration wheel 70-degree wafer: ; Center detecting wheel 0-degree wafer: ; Center detecting wheel rear-biased by 70 degrees wafer: ; Center detecting wheel is deflected 70 degrees forward with respect to the wafer: ; Front exploration wheel 0-degree wafer: ; 37-degree wafer of the front exploration wheel: ; 70-degree wafer of the front exploration wheel: ; Taking the rear detector wheel as the reference, the spatial conversion parameters of the rear detector wheel are not corrected; the spatial conversion parameter correction module (2) selects the position of the rail joint (90) in the detected B-scan image when the rail flaw detector runs at a low speed, and calculates the difference in the detection B-scan images of the 0-degree wafers of the front and rear detector wheels as , and the spatial conversion parameter correction module (2) calculates the corrected spatial conversion parameters of the front detector wheel according to the following formula: Front exploration wheel 0-degree wafer: ; Front exploration wheel 37-degree wafer: ; 70-degree wafer of the front exploration wheel: ; S204) The space conversion parameter correction module (2) calculates, according to the detected B-type pattern, that the distance difference between the center of the wafer detection pattern when the center probe wheel deflects by 70 degrees and the center of the Y-shaped feature pattern is , and the space conversion parameter correction module (2) calculates the corrected space conversion parameter of the center probe wheel according to the following formula: Center probe wheel 0-degree wafer: ; Center detecting wheel rearwardly deflected by 70 degrees wafer: ; Center probe wheel front offset 70 degrees wafer: .

4. The rail flaw detection B-type diagram reconstruction device according to claim 1, 2 or 3, characterized in that: The device further includes an amplitude filtering module (3). The B-scan image shows the positions of the detected damage points. The amplitude filtering module (3) uses the A-scan amplitude of the ultrasonic echo corresponding to the damage point as the display brightness of the corresponding detection point in the B-scan display.

5. The rail flaw detection B-type diagram reconstruction device according to claim 4, characterized in that: The amplitude filtering module (3) calculates the mean value of the A-scan amplitudes of the detection points of the same channel of the wafer (60) at the bolt hole (80) and the rail joint (90). , is the wafer channel number, and the amplitude filtering coefficient is manually adjusted , take , as the filtered amplitude; in the normal area where the probe wheel (30) is centered, that is, the centering deviation is within the allowable deviation , , the detection points lower than the filtered amplitude are not displayed, and the detection B-scan image is regenerated. Manual-assisted damage identification is performed according to the displayed image, and a suitable amplitude filtering coefficient is selected.

6. The rail flaw detection B-type diagram reconstruction device according to claim 1, 2, 3 or 5, characterized in that: The device further includes a damage mirror image restoration module (4). The mirror image position of the detected B-scan image is determined by the coordinates of the rail joint (90). The ultrasonic wave emitted by the 37-degree rear wafer is reflected by the rail joint (90) to detect a point to form a mirror image detection point . The actual damage restores the point according to the position of the point . Let the coordinates of the rail joint (90) be , be the angle of the 37-degree rear wafer. Then when the point satisfies the condition , the coordinates of the point restored by the mirror image restoration module (4) are: 。 7. The rail flaw detection B-type diagram reconstruction device according to claim 6, characterized in that: The ultrasonic wave emitted by the 37-degree front wafer is detected at a point through reflection by the rail joint (90). And a mirror detection point is formed . The actual damage is restored according to the point . Let the coordinates of the rail joint (90) be . , be the angle of the 37-degree front wafer; then when satisfies , the coordinates of the point mirror-restored by the mirror restoration module (4) are: 。 8. The rail flaw detection B-type diagram reconstruction device according to claim 1, 2, 3, 5 or 7, characterized in that: The device further includes a misalignment filtering module (5). When the probe wheel (30) deviates from the rail (40) at a line curve, the automatic alignment system is used to detect, control, and record the deviation value at the corresponding position of the detected B-mode diagram. When the probe wheel (30) is misaligned and the deviation value is greater than the set value and when the ultrasonic wave bottom echo of the rail from the 0-degree wafer is not lost, the misalignment filtering module (5) filters out the detection reflection points (100) of the rail jaw part of the rail (40) in the detected B-mode diagram to achieve misalignment filtering; let the height of the rail jaw from the rail surface be , the measurement error limit value be When is the ordinate of the B-mode diagram, the misalignment filtering module (5) needs to meet the following three conditions simultaneously for misalignment filtering: ⅰ) The bottom wave is not lost; ⅱ） ； ⅲ） 。 9. The rail flaw detection B-type diagram reconstruction device according to claim 8, wherein: The device further includes a detection channel missing warning module (6). When passing through the area with rail joints (90) and bolt holes (80), except for the side-scan channel, corresponding feature points are displayed in the detected B-scan image, and the missing part is displayed as the corresponding channel missing by the detection channel missing warning module (6).

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