Track damage inspection device and method based on flexible film pressure sensor

Abstract

The invention discloses a track damage inspection device and method based on a flexible film pressure sensor, and relates to the field of track damage detection.The inspection device comprises a mounting base and a detection device; the detection device comprises a pressure sensing module and a supporting module; the supporting module and the mounting seat ensure that the device stably runs on a railway track; a pressure detection device in the pressure sensing module is responsible for track damage detection, nylon bristles on a flexible film pressure sensor wrap and press a track in all directions from three directions and transmit pressure information and changes back in a function form, and when no obvious damage or foreign matter exists on the surface of the track, a function value is within an error range, and the pressure sensing module is used for detecting the damage of the track. When the track is damaged or foreign matters exist, the function fluctuates, and the area and the volume of a concave or convex region on the surface of the track can be obtained by performing double integration and triple integration on the function value, so that the purpose of detecting the damage state of the track is achieved.

Description

Technical Field

[0001] The present invention relates to the field of track damage detection, and in particular to a track damage inspection device and method based on a flexible film pressure sensor. Background Art

[0002] The rail inspection device is a device used to monitor and evaluate the status of railway tracks, aiming to ensure the safe operation of the railway. There are three main inspection methods in the rail maintenance process, including heavy inspection vehicle inspection, small double-track inspection equipment inspection and manual single-track inspection. The diversified development of rail inspection devices has not only improved the efficiency and accuracy of rail inspection, but also provided a solid guarantee for railway safety.

[0003] Within the existing technical scope, the traditional method of manual inspection is often used, which includes two modes: foot inspection and on-board inspection. In the foot inspection mode, inspectors use inspection tools such as inspection hammers to determine the damage to the railway in a step-by-step manner. This method has obvious shortcomings, which are manifested in poor inspection efficiency, limited railway line sections that can be covered by a single inspection, and high work intensity of inspectors. In the on-board inspection mode, inspectors take a train in operation to observe the damage to the railway. This mode relies heavily on the observation ability of inspectors, and in actual applications, its detection precision and accuracy are both at a low level.

[0004] Chinese patent CN104535652A discloses a rail damage detection method, which uses image detection equipment to process real-time images of rails, and uses ultrasonic detection equipment to perform ultrasonic detection on rails. The damage degree of the rails is determined based on the processing results of the two, and discrete defects and corrugation defects of the rails can be identified; and the use of automatic equipment reduces labor costs.

[0005] Chinese patent CN205301239U discloses a non-destructive detection device for rail defects. By measuring the static magnetic force generated by a permanent magnet, it can confirm whether there are defects or damages and determine the locations of the defects and damages, but it cannot determine the detailed information of the damage or defects.

[0006] Nowadays, there is a need for a rail non-destructive inspection and detection device that can reduce labor costs and accurately determine the location and detailed information of track defects or damages. Summary of the invention

[0007] The problem to be solved by the present invention is how to propose a more convenient, more efficient and more accurate rail damage detection method.

[0008] To solve the above problems, the present invention proposes the following solutions:

[0009] A track damage inspection device based on a flexible film pressure sensor, the key technology of which is that the device comprises a mounting seat and a detection device; wherein the mounting seat is a door-shaped structure, used to connect the inspection vehicle and the load-bearing detection device, and the detection device is installed inside the mounting seat; the detection device comprises a pressure sensing module and a support module;

[0010] The support module includes a crossbeam, a track clamp installed on the crossbeam, and a control rod for controlling the distance between the clamps; the track clamp includes a sleeve, a straight plate, a curved plate, and a clamp body; the sleeve is sleeved on the crossbeam, the sleeve is connected to the straight plate below, and the curved plate is connected to the other end of the sleeve and the straight plate to enhance the structural stability; the connection between the curved plate and the straight plate is connected to the clamp body; the control rod includes a straight rod and a connecting piece, and the straight rod is connected to two sleeves respectively through the connecting piece;

[0011] The pressure sensing module includes a fixed block, a wiring box, a pressure detection device and a guiding device; wherein the pressure detection device includes a three-sided frame, nylon bristles and a flexible film pressure sensor; wherein the fixed block is mounted in the middle of the crossbeam, and is connected to the wiring box below, and the wiring box is connected to the three-sided frame below, and a flexible film pressure sensor is arranged on the inner surface of the three-sided frame, and the nylon bristles are arranged in a matrix and fixed on the surface of the flexible film pressure sensor; the guiding device includes a pair of pulleys arranged on the fixed block and connected by thin rods, two pairs of small pulleys arranged on the outer surfaces of both sides of the three-sided frame and connected by thin rods, and a track transmission assembly; the track transmission assembly includes two sets of tracks, which are connected between the clamping plate and the rail through thin rods.

[0012] The pressure detection device is used to detect rail damage, wherein the nylon bristles are used to transfer the pressure generated by the contact between the rail and the device to the flexible film pressure sensor.

[0013] The flexible film pressure sensor is used to collect the pressure transmitted by the nylon bristles and transmit the pressure signal to the computer. The computer calculates the area and volume of the track damage through the change amplitude of the pressure signal.

[0014] The data port of the flexible film pressure sensor is connected to the signal receiving device in the inspection vehicle through a wiring box; the power port of the flexible film pressure sensor is connected to the power supply in the inspection vehicle through a wiring box.

[0015] The diameters of the pulley and the small pulley are selected according to the length of the nylon bristles. The diameters of the pulley and the small pulley are slightly smaller than the length of the nylon bristles to ensure the detection sensitivity of the nylon bristles to track damage. The pulley and the small pulley slide on the corresponding surfaces of the track.

[0016] A track damage inspection method based on a flexible film pressure sensor, the method is accomplished by means of a track damage inspection device according to any one of claims 1 to 5, characterized in that it comprises the following steps:

[0017] 1) Check whether the device is running;

[0018] 2) After the device is turned on, the flexible film pressure sensor receives the pressure signal through the nylon bristles and transmits it to the computer;

[0019] 3) When the received pressure signal fluctuates, the computer calculates the area of ​​the fluctuation and controls the inspection vehicle to re-pass at a slower speed;

[0020] 4) After re-driving, more accurate data is obtained. The computer uses the more accurate data to calculate the volume of the fluctuation and output the location, area, volume and morphological information of the track defect;

[0021] 5) The device continues to run and the inspection vehicle continues to move forward.

[0022] The computer displays the pressure coefficient in the form of a function, which is specifically expressed as the product of the stress of the nylon bristles and the cross-sectional area of ​​the nylon bristles; the computer processes data at the fluctuation point of the function and calculates the area and volume at the fluctuation point.

[0023] The benefits of adopting a technical solution are:

[0024] The present invention uses nylon bristles to contact the track and transmit the pressure between the nylon bristles and the track to the flexible film pressure sensor. The precise pressure perception and transmission perception mechanism provide a data basis for accurately judging damage. In addition, due to the adjustable length of the nylon bristles, it can adapt to different track environments and improve universality.

[0025] The present invention uses an automated device to replace manual inspection. The nylon brush always follows the inspection vehicle to sense the pressure of the track. It can continue to run without stopping before pressure fluctuations occur, thus avoiding frequent stops and human intervention, thereby improving inspection efficiency.

[0026] The present invention uses pressure sensing to determine track damage, and can quickly and accurately determine whether the damage type is a protrusion or a depression through changes in pressure, thereby providing a data basis for subsequent maintenance and reducing the time for the overall inspection and maintenance process.

[0027] The present invention uses a computer to calculate the area and volume of the damaged part, providing accurate data for subsequent repair and maintenance, which is helpful for the formulation of maintenance plans. In addition, through the long-term accumulation of these data and analysis of data trends, data support can be provided for the adjustment of track maintenance and train operation plans. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0029] Figure 1 A schematic diagram of the inspection method for detecting rail damage based on a flexible film pressure sensor proposed in the present invention;

[0030] Figure 2 This is an overall schematic diagram of the inspection device for detecting rail damage based on a flexible film pressure sensor proposed in the present invention;

[0031] Figure 3 This is a schematic diagram of the inspection device for detecting rail damage based on the flexible film pressure sensor proposed by the present invention after the mounting seat is removed;

[0032] Figure 4 for Figure 3 A partial enlarged view of part A;

[0033] Figure 5 This is a schematic diagram of a pressure detection module in an inspection device for detecting rail damage based on a flexible film pressure sensor proposed by the present invention;

[0034] Figure 6 for Figure 5 A partial enlarged view of part B;

[0035] Figure 7 It is a two-dimensional image formed by the pressure change of the flexible film pressure sensor in the inspection device proposed by the present invention when encountering a protrusion;

[0036] Figure 8 It is a two-dimensional image formed by the pressure change of the flexible film pressure sensor in the inspection device proposed by the present invention when it encounters a concave;

[0037] Fig. 9 A three-dimensional image formed by the pressure change when the flexible film pressure sensor in the inspection device proposed by the present invention encounters a protrusion;

[0038] Description of Reference Numerals

[0039] 1. Mounting seat; 2. Support module; 21. Crossbeam; 22. Track clamp; 221. Sleeve; 222. Straight plate; 223. Curved plate; 224. Clamp body; 23. Control rod; 231. Straight rod; 232. Connector; 3. Pressure sensing module; 31. Fixed block; 32. Wiring box; 33. Pressure detection device; 331. Three-sided frame; 332. Nylon bristles; 333. Flexible film pressure sensor; 34. Guide device; 341. Pulley; 342. Small pulley; 343. Track transmission device. DETAILED DESCRIPTION

[0040] In order to make the features and advantages of the present invention more obvious and easy to understand, the technical solution will be clearly and completely described below in combination with the drawings and specific implementation methods. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0041] The embodiment of the present invention discloses a track damage inspection device and method based on a flexible film pressure sensor, comprising the following steps:

[0042] like Figure 2-6 The device shown includes a mounting base 1 and a detection device; wherein the detection device includes a pressure sensing module 3 and a support module 2; the pressure sensing module 3 includes a fixed block 31, a wiring box 32, a pressure detection device 33 and a guide device 34; wherein the fixed block 31 is sleeved in the middle of the crossbeam 21, and is connected to the wiring box 32 below, and the wiring box 32 is connected to a three-sided frame 331 below, and a flexible film pressure sensor 333 is arranged on the inner surface of the three-sided frame 331, and nylon bristles 332 are arranged in a matrix and fixed on the surface of the flexible film pressure sensor 333; the guide device 34 includes a pair of pulleys 341 arranged on the fixed block 31 and connected by thin rods, two pairs of small pulleys 342 arranged on the outer surfaces of both sides of the three-sided frame 331 and connected by thin rods, and a track transmission assembly 343; the track transmission assembly 343 includes two sets of tracks, which are connected between the clamping plate and the rail through thin rods.

[0043] The nylon bristles 332 play the role of connecting the flexible film pressure sensor 333 and the track surface, establishing a close and effective contact relationship between the sensor and the track; in this embodiment, they are arranged in a matrix and fixed on the surface of the flexible film pressure sensor 333, and are respectively fixed in the pores of the hard porous plate. When the nylon bristles 332 are squeezed, the corresponding area of ​​the flexible film pressure sensor 333 will produce a change in the pressure signal, which is converted into a change in the electrical signal and then transmitted to the computer to convey the pressure information.

[0044] The flexible film pressure sensor 333 is a device that detects when the material is subjected to external pressure and its electrical and other properties change. When external pressure acts on the flexible film pressure sensor 333, the electrical and other properties of its sensitive material change accordingly, generating a corresponding electrical signal. This signal is amplified and converted by the circuit and finally converted into recognizable data, thereby realizing the perception, monitoring and feedback of specific physical quantities.

[0045] As the core sensing part of the entire detection system, the flexible film pressure sensor 333 has a highly sensitive characteristic and can accurately sense the change in pressure; the flexible film pressure sensor 333 collects the pressure transmitted by the nylon bristles 332 and transmits the pressure signal to the computer. The computer calculates the area and volume of the track damage by the change amplitude of the pressure signal; in this embodiment, the flexible film pressure sensor 333 has two ports: a power port and a signal port, which are respectively connected to the signal receiving device and the power supply in the inspection vehicle; the power port of the flexible film pressure sensor 333 is divided into a power input terminal and a ground terminal. The power input terminal is connected to the positive pole of the power supply to provide the power supply voltage required by the sensor; the ground terminal is connected to the negative pole of the power supply to provide a circuit loop. The signal terminal of the flexible film pressure sensor 333 sends an output signal, which carries the information of the pressure or force received, that is, an analog voltage signal, which is connected to the analog input channel or data acquisition card in the signal receiving device in the inspection vehicle.

[0046] When the track has concave damage, the sensor pressure decreases; when the track has protruding damage or there are foreign objects on the track, the sensor pressure increases.

[0047] The guide device 34 is responsible for the smoother operation of the inspection device on the railway track, and the coordinated use of the pulley 341, the small pulley 342 and the crawler drive assembly 343 ensures that the device runs in close contact with the track.

[0048] The diameters of the pulley 341 and the small pulley 342 correspond to the lengths of the corresponding nylon bristles 332 , and the diameters of the pulley 341 and the small pulley 342 are slightly smaller than the lengths of the nylon bristles 332 . The pulley 341 and the small pulley 342 slide on the corresponding surfaces of the track.

[0049] The crawler drive assembly 343 provides a stable operating condition for the inspection vehicle in the operation mechanism of the inspection vehicle, ensuring that it can move smoothly along the rails, and the crawler drive assembly 343 is used for guiding between the track clamping plate 22 and the I-shaped rail, and the two crawlers are symmetrically distributed in the gap between the track clamping plate 22 and the side of the rail.

[0050] The support module 2 includes a crossbeam 21, a track clamp 22 installed on the crossbeam 21, a control rod 23 for controlling the distance between the clamps, and a track transmission assembly 343; the track clamp 22 includes a sleeve 221, a straight plate 222, an arc plate 223 and a clamp body 224; the sleeve 221 is sleeved on the crossbeam 21, the straight plate 222 is connected below the sleeve 221, and the arc plate 223 is connected to the other end of the sleeve 221 and the straight plate 222 to enhance the structural stability; the control rod 23 is connected to the two sleeves 221 through the connecting piece 232.

[0051] The support module 2 provides support for the entire detection process and ensures its normal operation. The inspection vehicle equipped with the inspection device has stable operating performance and reasonable structural design, and can run smoothly along the rails, thereby driving the entire inspection device to complete a comprehensive inspection of the track.

[0052] The straight rod 231 in the control rod 23 is connected to the sleeve 221 on the track clamp 22 through the connecting piece 232. The sleeve 221 is driven to move by rotating the straight rod 231, and the auxiliary track clamp 232 is close to the track, so that the crawler drive assembly 343 in the guide device 34 is closely fitted with the track.

[0053] like Figure 1 As shown, when the inspection vehicle is running normally along a predetermined route above the rail, the nylon bristles 332 are arranged in a matrix and fixed on the surface of the flexible film pressure sensor 333. Each nylon bristle 332 has a corresponding position on the sensor (indicated by coordinates (Xn, Yn)). When the bristles contact the rail and are squeezed and bent by the operation of the inspection vehicle, pressure is generated on the flexible film pressure sensor 333.

[0054] In the running state, some data changes, such as the cross-sectional area A, elastic modulus E, original length L and variable length ΔL of the bristles, where the variable length and the original length can characterize the strain of the nylon bristles 332, and the elastic modulus and strain of the bristles can further characterize the stress of the bristles. Finally, the elastic force of the bristles, i.e., the pressure on the sensor, is calculated by the stress and the cross-sectional area of ​​the bristles. When the track is normal, the nylon bristles 332 are in a normal state; Figure 7-8 As shown, when the track has concave damage, the bristles will stretch and the change length ΔL will decrease. Correspondingly, the pressure (elastic force F) on the sensor will also decrease. When the track has protruding damage or foreign matter exists, the bristles will be further compressed, ΔL will increase, and the pressure (elastic force F) on the sensor will increase.

[0055] The changes in the nylon bristles 332 can sensitively detect the pressure on the rails, and can also transmit pressure-related information and dynamic changes in pressure back to the data processing system in real time in the form of precise functions.

[0056] like Fig. 9As shown, when the pressure signal fluctuates, the flexible film pressure sensor 333 will transmit the signal to the computer. The computer relies on the pre-set algorithm and model, and combines the geometric parameters such as the shape and size of the track and the location where the sensor is installed, to carefully and deeply analyze the received pressure signal, with the purpose of accurately calculating the size (area and volume) of the protruding or concave part of the track surface, thereby providing a strong basis for evaluating the degree of track damage. The specific operation is: first set the maximum pressure Fmax and the minimum pressure Fmin for each bristle, which is the range of normal pressure changes when the rail is running normally. When the pressure F felt by the flexible film pressure sensor 333 exceeds this normal range (greater than Fmax or less than Fmin), the position of the bristle at this time (Xn, Yn) is recorded. After the inspection vehicle passes the track damage area, through these recorded (Xn, Yn) data groups, (X0, Y0) represents the position where the damage starts, (X1, Y1) represents the position where the damage ends, and the integral from the starting position to the end position is used to characterize the area of ​​the damaged part.

[0057] For specific areas where the pressure signal fluctuates, the inspection vehicle will re-pass through this area at a relatively slow and stable speed. By measuring again, more accurate data information of this area can be further collected in a more detailed manner, especially a more accurate change length ΔL can be obtained. Similarly, (X0, Y0) is the initial position of the damage, (X1, Y1) is the final position of the damage, and the starting position, end position and change length are triple-integrated to characterize the damage volume. Based on these more detailed data, the volume V of the fluctuating area is calculated, so that the calculated volume V value will be more accurate and reliable; in specific use: the computer uses the formula:

[0058] strain

[0059] Stress σ=E×ε

[0060] That is, under normal circumstances

[0061] Elastic force F = σ × A

[0062] The pressure data received by the flexible film pressure sensor 333 is processed and calculated, and the position of the protrusion or depression defect on the track surface is obtained by combining the specific parameters of the track and the installation position of the sensor. The area of ​​the defect is calculated by the formula:

[0063]

[0064] Combined with the collected pressure information, the final area of ​​track damage is:

[0065]

[0066] Similarly, according to the formula:

[0067]

[0068] Calculate the volume of the defect and combine it with the pressure signal to get the final volume of the track damage:

[0069]

[0070] After completing the above operations, if the pressure signal does not fluctuate, the detection device will continue to perform subsequent inspections according to the predetermined inspection plan and established operating trajectory.

Claims

1. A track damage inspection device based on a flexible film pressure sensor, characterized in that: The device comprises a mounting seat (1) and a detection device; wherein the mounting seat (1) is a door-shaped structure, used to connect the inspection vehicle and the load-bearing detection device, and the detection device is installed inside the mounting seat (1); the detection device comprises a pressure sensing module (3) and a support module (2); The support module (2) comprises a crossbeam (21), a track clamp (22) mounted on the crossbeam (21), and a control rod (23) for controlling the distance between the clamps; the track clamp (22) comprises a sleeve (221), a straight plate (222), a curved plate (223), and a clamp body (224); the sleeve (221) is sleeved on the crossbeam (21), the straight plate (222) is connected below the sleeve (221), and the curved plate (223) is connected to the other end of the sleeve (221) and the straight plate (222) to enhance structural stability; the connection between the curved plate (223) and the straight plate (222) is connected to the clamp body (224); the control rod (23) comprises a straight rod (231) and a connecting piece (232), and the straight rod (231) is respectively connected to the two sleeves (221) through the connecting piece (232); The pressure sensing module (3) comprises a fixed block (31), a wiring box (32), a pressure detection device (33) and a guide device (34); wherein the pressure detection device (33) comprises a three-sided frame (331), nylon bristles (332) and a flexible film pressure sensor (333); wherein the fixed block (31) is sleeved in the middle of the crossbeam (21), and is connected to the wiring box (32) below; the wiring box (32) is connected to the three-sided frame (331) below; and the inner surface of the three-sided frame (331) is provided with A flexible film pressure sensor (333), wherein the nylon bristles (332) are arranged in a matrix and fixed on the surface of the flexible film pressure sensor (333); the guiding device (34) comprises a pair of pulleys (341) arranged on a fixed block (31) and connected by thin rods, two pairs of small pulleys (342) arranged on the outer surfaces of both sides of the three-sided frame (331) and connected by thin rods, and a crawler transmission assembly (343); the crawler transmission assembly (343) comprises two sets of crawlers connected between a clamping plate and a rail through thin rods.

2. A track damage inspection device based on a flexible film pressure sensor according to claim 1, characterized in that: The pressure detection device (33) is used to detect rail damage, wherein the nylon bristles (332) are used to transmit the pressure generated by the contact between the rail and the device to the flexible film pressure sensor (333).

3. A track damage inspection device based on a flexible film pressure sensor according to claim 1, characterized in that: The flexible film pressure sensor (333) is used to collect the pressure transmitted by the nylon bristles (332) and transmit the pressure signal to the computer. The computer calculates the area and volume of the track damage through the amplitude of the pressure signal change.

4. A track damage inspection device based on a flexible film pressure sensor according to claim 1, characterized in that: The data port of the flexible film pressure sensor (333) is connected to a signal receiving device in the inspection vehicle through a wiring box (32); and the power port of the flexible film pressure sensor (333) is connected to a power supply in the inspection vehicle through a wiring box (32).

5. A track damage inspection device based on a flexible film pressure sensor according to claim 1, characterized in that: The diameters of the pulley (341) and the small pulley (342) are selected according to the length of the nylon bristles (332). The diameters of the pulley (341) and the small pulley (342) are slightly smaller than the length of the nylon bristles (332) to ensure the detection sensitivity of the nylon bristles (332) to track damage. The pulley (341) and the small pulley (342) slide on the corresponding surfaces of the track.

6. A rail damage inspection method based on a flexible film pressure sensor, the method being accomplished by means of a rail damage inspection device as claimed in any one of claims 1 to 5, characterized in that: The following steps are involved: 1) Check whether the device is running; 2) After the device is turned on, the flexible film pressure sensor (333) receives the pressure signal through the nylon bristles (332) and transmits it to the computer; 3) When the received pressure signal fluctuates, the computer calculates the area of ​​the fluctuation and controls the inspection vehicle to re-pass at a slower speed; 4) After re-driving, more accurate data is obtained. The computer uses the more accurate data to calculate the volume of the fluctuation and output the location, area, volume and shape information of the track defect; 5) The device continues to run and the inspection vehicle continues to move forward.

7. A rail damage inspection method based on a flexible film pressure sensor according to claim 6, characterized in that: The computer displays the pressure coefficient in the form of a function, which is specifically expressed as the product of the stress of the nylon bristles (332) and the cross-sectional area of ​​the nylon bristles (332); the computer processes data at the fluctuation point of the function and calculates the area and volume at the fluctuation point.

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