Calibration system and method for ultrasonic channel of rail flaw detection system

Abstract

The present invention discloses a calibration system and method for the ultrasonic channel of a rail flaw detection system. The system includes: an ultrasonic channel calibration test block for generating reflected waves of different preset sound ranges in response to an excitation signal of the rail flaw detection system; a reflected wave processing unit for obtaining a first amplified signal corresponding to the reflected wave of the specified sound range from each ultrasonic channel; determining a signal amplification gain value for the first amplified signal of each ultrasonic channel; calculating, for each ultrasonic channel, a gain difference between the signal amplification gain value of the first amplified signal of the ultrasonic channel and the signal amplification gain values of the first amplified signals of other ultrasonic channels; and an ultrasonic channel calibration unit for calibrating the signal amplification gain values of the different ultrasonic channels based on the corresponding gain value differences when performing rail flaw detection in different ultrasonic channels. The present invention can achieve standardized calibration of the ultrasonic channels of the rail flaw detection system, thereby improving the calibration accuracy and efficiency of the ultrasonic channels of the rail flaw detection system.

Description

Technical Field

[0001] The present invention relates to the field of railway technology, and in particular to a calibration system and method for an ultrasonic channel of a rail flaw detection system. Background Art

[0002] This section is intended to provide a background or context to the embodiments of the invention that are recited in the claims. No statement herein is admitted to be prior art by virtue of its inclusion in this section.

[0003] Currently, rail flaw detection vehicles are equipped with rail flaw detection systems. These systems, based on the ultrasonic testing principle and using wheeled probe sensors, can rapidly inspect in-service rails. The effective detection range and flaw detection process of ultrasonic systems have also been gradually improved, playing a vital role in ensuring rail safety.

[0004] During rail flaw detection vehicle inspections, parameters such as the ultrasonic channel signal amplification gain of the rail flaw detection system need to be adjusted based on data quality. Due to the lack of calibration and standardization of ultrasonic channels, parameter values vary significantly between different channels. Furthermore, operators can only adjust parameters for one channel at a time, and the adjustment range depends on their experience, which is subject to human subjectivity. This results in low usability of the equipment and significant variability in the performance of the same equipment when used by different operators. This ultimately impacts the effectiveness of the rail flaw detection vehicle's damage detection and the credibility of the test results.

[0005] However, there is currently no standardized calibration solution for the ultrasonic channel of the rail flaw detection system. Summary of the Invention

[0006] An embodiment of the present invention provides a calibration system for an ultrasonic channel of a rail flaw detection system, which is applied to a rail flaw detection vehicle to achieve standardized calibration of the ultrasonic channel of the rail flaw detection system, thereby improving the calibration accuracy and efficiency of the ultrasonic channel of the rail flaw detection system. The system includes:

[0007] The ultrasonic channel calibration test block is configured to generate ultrasonic waves in response to an excitation signal of a rail flaw detection system; perform multiple attenuation reflections on the ultrasonic waves to generate reflected waves of different preset sound ranges; and reflect the reflected waves of different preset sound ranges toward each ultrasonic channel of the rail flaw detection system; and each ultrasonic channel of the rail flaw detection system is configured to amplify the received reflected waves of different preset sound ranges to obtain processed amplified signals.

[0008] a reflected wave processing unit configured to obtain, from each ultrasonic channel, a first amplified signal corresponding to a reflected wave in a specified sound path; determine a signal amplification gain value for the first amplified signal of each ultrasonic channel; and calculate, for each ultrasonic channel, a difference between the signal amplification gain value of the first amplified signal of the ultrasonic channel and the signal amplification gain values of the first amplified signals of other ultrasonic channels;

[0009] The ultrasonic channel calibration unit is used to calibrate the signal amplification gain values of different ultrasonic channels according to the corresponding gain value differences when performing rail flaw detection in different ultrasonic channels.

[0010] An embodiment of the present invention further provides a method for calibrating an ultrasonic channel of a rail flaw detection system, which is applied to the calibration system for the ultrasonic channel of a rail flaw detection system as described above. The calibration system for the ultrasonic channel of a rail flaw detection system is applied to a rail flaw detection vehicle to achieve standardized calibration of the ultrasonic channel of the rail flaw detection system, thereby improving the calibration accuracy and efficiency of the ultrasonic channel of the rail flaw detection system. The method includes:

[0011] The ultrasonic channel calibration test block generates ultrasonic waves in response to an excitation signal of the rail flaw detection system; performs multiple attenuation reflections on the ultrasonic waves to generate reflected waves of different preset sound ranges; reflects the reflected waves of different preset sound ranges toward each ultrasonic channel of the rail flaw detection system; and each ultrasonic channel of the rail flaw detection system is configured to amplify the received reflected waves of different preset sound ranges to obtain processed amplified signals.

[0012] The reflected wave processing unit obtains a first amplified signal corresponding to a reflected wave in a specified sound path from each ultrasonic channel; determines a signal amplification gain value of the first amplified signal of each ultrasonic channel; and calculates, for each ultrasonic channel, a gain difference between the signal amplification gain value of the first amplified signal of the ultrasonic channel and the signal amplification gain values of the first amplified signals of other ultrasonic channels;

[0013] When the ultrasonic channel calibration unit performs rail flaw detection in different ultrasonic channels, the signal amplification gain values of the different ultrasonic channels are calibrated according to the corresponding gain value differences.

[0014] In an embodiment of the present invention, an ultrasonic channel calibration test block is used to generate ultrasonic waves in response to an excitation signal of a rail flaw detection system; perform multiple attenuation reflections on the ultrasonic waves to generate reflected waves of different preset sound ranges; reflect the reflected waves of different preset sound ranges to each ultrasonic channel of the rail flaw detection system; each ultrasonic channel in the rail flaw detection system is used to perform signal amplification processing on the received reflected waves of different preset sound ranges to obtain a processed amplified signal; a reflected wave processing unit is used to obtain a first amplified signal corresponding to the reflected wave of a specified sound range from each ultrasonic channel; determine a signal amplification gain value of the first amplified signal of each ultrasonic channel; and calculate, for each ultrasonic channel, the signal amplification gain value of the first amplified signal of the ultrasonic channel and the gain of the signal amplification gain value of the first amplified signal of other ultrasonic channels. value difference; an ultrasonic channel calibration unit, which is used to calibrate the signal amplification gain values of different ultrasonic channels according to the corresponding gain value differences when performing rail flaw detection in different ultrasonic channels. Compared with the technical solutions in the prior art that require manual calibration of the ultrasonic channels, by setting the ultrasonic channel calibration test blocks to reflect reflected waves of different preset sound ranges, and determining the gain value differences of the signal amplification gain values of the first amplified signals of the reflected waves of the specified sound ranges in different ultrasonic channels, the calibration process of the signal amplification gain values between different ultrasonic channels can be quantified, and the standardized calibration of the transmission characteristics of different ultrasonic channels can be achieved. This not only improves the calibration accuracy of the ultrasonic channels of the rail flaw detection system, but also avoids the inevitable calibration errors due to manual adjustment, and at the same time improves the calibration efficiency of the ultrasonic channels of the rail flaw detection system. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0016] Figure 1 This is a structural diagram of a wheel probe sensor in an embodiment of the present invention;

[0017] Figure 2 This is a specific example diagram of the connection between an ultrasound channel and a wheel probe in an embodiment of the present invention;

[0018] Figure 3 This is a structural example diagram of a calibration system for an ultrasonic channel of a rail flaw detection system according to an embodiment of the present invention;

[0019] Figure 4 This is a specific example diagram of an ultrasonic channel calibration test block in an embodiment of the present invention;

[0020] Figure 5 Schematic diagram of echo generation in an ultrasound channel according to an embodiment of the present invention;

[0021] Figure 6 This is a specific example diagram of a cable interface of an ultrasonic channel calibration test block in an embodiment of the present invention;

[0022] Figure 7 This is a specific example diagram of an ultrasonic channel calibration test block in an embodiment of the present invention;

[0023] Figure 8 This is a specific example diagram of reference echoes calibrated in different ultrasound channels according to an embodiment of the present invention;

[0024] Figure 9 The figure is a flowchart illustrating a calibration method for an ultrasonic channel of a rail flaw detection system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0025] To make the purpose, technical solutions and advantages of the embodiments of the present invention more clear, the embodiments of the present invention are further described in detail below with reference to the accompanying drawings. Here, the exemplary embodiments of the present invention and their descriptions are used to explain the present invention, but are not intended to limit the present invention.

[0026] Currently, rail flaw detection vehicles are equipped with rail flaw detection systems. These systems, based on the ultrasonic testing principle and using wheeled probe sensors, can rapidly inspect in-service rails. The effective detection range and flaw detection process of ultrasonic systems have also been gradually improved, playing a vital role in ensuring rail safety.

[0027] During rail flaw detection vehicle inspections, parameters such as the ultrasonic channel signal amplification gain of the rail flaw detection system need to be adjusted based on data quality. Due to the lack of calibration and standardization of ultrasonic channels, parameter values vary significantly between different channels. Furthermore, operators can only adjust parameters for one channel at a time, and the adjustment range depends on their experience, which is subject to human subjectivity. This results in low usability of the equipment and significant variability in the performance of the same equipment when used by different operators. This ultimately impacts the effectiveness of the rail flaw detection vehicle's damage detection and the credibility of the test results.

[0028] However, there is currently no solution for automated calibration of the ultrasonic channel of the rail flaw detection system.

[0029] Further analysis by the inventors revealed that there are two main reasons for the large parameter differences between ultrasound channels:

[0030] (1) The signal transmission characteristics of the ultrasonic channel of the rail flaw detection system are different. The ultrasonic trigger signal excited by the electronic cabinet installed in the rail flaw detection vehicle is converted into an acoustic wave signal after passing through the connecting cables inside and under the vehicle and then reaching the wheel probe. The acoustic wave signal is reflected by the damage inside the rail and is then detected by the wheel probe (such as Figure 1 The ultrasonic signal is received (as shown) and then returned to the electronics cabinet via the connecting cable for processing and analysis. The ultrasonic channel's signal transmission path is long, subject to high interference, and has a poor signal-to-noise ratio. This results in inconsistent signal transmission characteristics between different ultrasonic channels, making it impossible to normalize detection parameters. Currently, there are no ultrasonic channel calibration tools or methods specifically designed for rail flaw detection systems.

[0031] The rail flaw detection system has eight ultrasonic signal transmission and reception analog circuit boards, which are connected one-to-one with the eight wheel probes under the vehicle, providing the functions of transmitting ultrasonic excitation signals, receiving, and conditioning echo signals. Each analog circuit board has six ultrasonic channels, corresponding to the six ultrasonic transducers in the wheel probes. The connection diagram of the rail flaw detection system electronic cabinet and wheel probes is shown in the figure. Figure 2 shown.

[0032] (2) Wheel probe sensor technical parameters vary. Wheel probes are equipped with ultrasonic sensors at multiple angles and wrapped with a flexible outer membrane. They are pressed against the rail surface with a certain pressure, performing flaw detection in a continuous rolling manner. However, differences in sensitivity and signal-to-noise ratio between sensors result in differences in detection parameters between different wheel probes.

[0033] Therefore, in order to solve the problem of large differences in the signal transmission characteristics of the ultrasonic channels of the above-mentioned rail flaw detection vehicles, the embodiment of the present invention proposes a calibration system for the ultrasonic channels of the rail flaw detection system, which can conveniently complete the calibration of the signal transmission characteristics between the ultrasonic channels on the rail flaw detection vehicle without disassembling the electronic cabinet and cables on the vehicle, providing an effective technical means for the standardization of the detection parameters of the rail flaw detection vehicle, so as to realize the standardized calibration of the ultrasonic channels of the rail flaw detection system and improve the calibration accuracy and efficiency of the ultrasonic channels of the rail flaw detection system. Figure 3 As shown, the system includes:

[0034] The ultrasonic channel calibration test block 301 is configured to generate ultrasonic waves in response to an excitation signal from a rail flaw detection system; perform multiple attenuation reflections on the ultrasonic waves to generate reflected waves of different preset sound paths; and reflect the reflected waves of different preset sound paths toward each ultrasonic channel of the rail flaw detection system. Each ultrasonic channel of the rail flaw detection system is configured to amplify the received reflected waves of different preset sound paths to obtain processed amplified signals.

[0035] The reflected wave processing unit 302 is configured to obtain, from each ultrasonic channel, a first amplified signal corresponding to a reflected wave in a specified sound path; determine a signal amplification gain value of the first amplified signal of each ultrasonic channel; and calculate, for each ultrasonic channel, a gain difference between the signal amplification gain value of the first amplified signal of the ultrasonic channel and the signal amplification gain values of the first amplified signals of other ultrasonic channels;

[0036] The ultrasonic channel calibration unit 303 is used to calibrate the signal amplification gain values of different ultrasonic channels according to the corresponding gain value differences when rail flaw detection is performed in different ultrasonic channels.

[0037] In an embodiment of the present invention, an ultrasonic channel calibration test block is used to generate ultrasonic waves in response to an excitation signal of a rail flaw detection system; perform multiple attenuation reflections on the ultrasonic waves to generate reflected waves of different preset sound ranges; reflect the reflected waves of different preset sound ranges to each ultrasonic channel of the rail flaw detection system; each ultrasonic channel in the rail flaw detection system is used to perform signal amplification processing on the received reflected waves of different preset sound ranges to obtain a processed amplified signal; a reflected wave processing unit is used to obtain a first amplified signal corresponding to the reflected wave of a specified sound range from each ultrasonic channel; determine a signal amplification gain value of the first amplified signal of each ultrasonic channel; and calculate, for each ultrasonic channel, the signal amplification gain value of the first amplified signal of the ultrasonic channel and the gain of the signal amplification gain value of the first amplified signal of other ultrasonic channels. value difference; an ultrasonic channel calibration unit, which is used to calibrate the signal amplification gain values of different ultrasonic channels according to the corresponding gain value differences when performing rail flaw detection in different ultrasonic channels. Compared with the technical solutions in the prior art that require manual calibration of the ultrasonic channels, by setting the ultrasonic channel calibration test blocks to reflect reflected waves of different preset sound ranges, and determining the gain value differences of the signal amplification gain values of the first amplified signals of the reflected waves of the specified sound ranges in different ultrasonic channels, the calibration process of the signal amplification gain values between different ultrasonic channels can be quantified, and the standardized calibration of the transmission characteristics of different ultrasonic channels can be achieved. This not only improves the calibration accuracy of the ultrasonic channels of the rail flaw detection system, but also avoids the inevitable calibration errors due to manual adjustment, and at the same time improves the calibration efficiency of the ultrasonic channels of the rail flaw detection system.

[0038] During specific implementation, an ultrasonic channel calibration test block is first used to respond to an excitation signal of a rail flaw detection system to generate an ultrasonic wave; the ultrasonic wave is subjected to multiple attenuation reflections to generate reflected waves of different preset sound ranges; the reflected waves of different preset sound ranges are reflected toward each ultrasonic channel of the rail flaw detection system; and each ultrasonic channel in the rail flaw detection system is used to amplify the received reflected waves of different preset sound ranges to obtain a processed amplified signal.

[0039] In one embodiment, an ultrasonic channel calibration block comprises:

[0040] An ultrasonic emitting device, an ultrasonic attenuation device bonded to the ultrasonic emitting end of the ultrasonic emitting device, and an ultrasonic reflecting device connected to the ultrasonic attenuation device and one end of the ultrasonic attenuation device;

[0041] An ultrasonic transmitter, used to generate ultrasonic waves in response to an excitation signal from a rail flaw detection system;

[0042] The ultrasonic attenuation device and the ultrasonic reflection device are used to perform multiple attenuation and reflection on the ultrasonic wave to generate reflected waves with different preset sound ranges.

[0043] In the above embodiment, if Figure 7 As shown, the ultrasonic emitting device may be: an ultrasonic transducer with a fixed frequency.

[0044] like Figure 4 As shown in Table 1, each ultrasonic channel calibration block can contain 6 fixed-frequency ultrasonic transducers. The number of transducers is the same as the number of transducers in the wheel probe, and the transducer frequency is the same as the transmission frequency of the ultrasonic channel, as shown in Table 1:

[0045] Table 1

[0046] Channel number Fixed echo probe frequency 1 3.50MHz 2 2.25MHz 3 2.25MHz 4 2.25MHz 5 2.25MHz 6 2.25MHz

[0047] In the above embodiment, if Figure 7 As shown, the ultrasonic attenuation device can be an ultrasonic attenuation material, which fits tightly with the transducer to ensure a stable coupling relationship.

[0048] In this example, the commonly used sound path range of the rail flaw detection system is 50-250 microseconds. Based on this sound path range, an ultrasonic attenuating material with a sound velocity of v can be selected and processed into a cylinder with a length of L. The relationship between L and V is: 2L / V = 50us. This ensures that after the ultrasonic wave propagates and reflects in the transmitting material, ultrasonic echoes with sound paths of 50us, 100us (secondary echo), 150us (tertiary echo), etc. are obtained in the rail flaw detection system. Figure 5 As shown, Figure 5 The reflected echoes generated by the ultrasonic channel with sound paths of 50, 100, and 150 μs are shown.

[0049] In the above embodiment, if Figure 7 As shown, the ultrasonic reflection device can be an ultrasonic reflection device, which is used to stick a circular steel sheet at the bottom end of the ultrasonic attenuation material as an ultrasonic reflection surface. The steel sheet is tightly fitted to the attenuation material, and air space is reserved on the back of the steel sheet to ensure that the ultrasonic wave is fully reflected at the steel sheet.

[0050] In one embodiment, the ultrasonic channel calibration test block further includes:

[0051] Sound-absorbing material device, used to prevent the ultrasonic sound beam from reflecting on the cylinder wall to form delayed waves;

[0052] Cable and plug assembly for connecting to rail flaw detection system;

[0053] The shell is used to protect the ultrasonic emitting device, the ultrasonic attenuation device, the ultrasonic reflecting device and the sound absorbing material device.

[0054] In the above embodiment, if Figure 7 As shown, the sound absorbing material device can be simply referred to as sound absorbing material. By wrapping a layer of ultrasonic sound absorbing material around the ultrasonic attenuation material, the ultrasonic sound beam is prevented from being reflected on the cylinder wall to form a late wave and thus interfere with the bottom echo signal.

[0055] In the above embodiment, the cable and plug device can be referred to as a cable and a plug. Each ultrasonic transducer can be connected by a multi-core cable and finally integrated into an electrical plug. The plug has the same definition as the wheel probe, which is convenient for replacement and connection. The structural example of the cable and plug can be shown as follows: Figure 6 The definition of cable plugs can be shown in Table 2:

[0056] Table 2

[0057]

[0058] In the above embodiment, the housing may be an aluminum square housing with a handle, and the cable plug is fixed outside the housing for easy carrying and cable connection.

[0059] As mentioned above, ultrasonic channel calibration requires the use of a unified ultrasonic transducer and a stable reflector. This application uses an ultrasonic channel calibration test block, which can be used as both an ultrasonic transducer and a reflector with a stable coupling relationship and a fixed sound path.

[0060] Compared with other current alternatives, such as using the same wheel probe to install in each installation location, there are two problems:

[0061] First, after the probe wheel moves to different installation positions, the coupling relationship between the probe wheel and the rail is not exactly the same due to the different water film thickness, water film distribution, and rail surface conditions between the probe wheel and the rail, resulting in the inability to form a stable contrast relationship between the ultrasonic echo signals.

[0062] Secondly, the reflection state of the rail bottom surface at different positions is inconsistent, which will also cause deviations in the ultrasonic echo signal and affect the accuracy of the calibration data.

[0063] The present application uses an ultrasonic channel calibration test block as both an ultrasonic transducer and a reflector with a stable coupling relationship and a fixed sound range, which can be conveniently connected to a rail flaw detection system. Switching between different ultrasonic channels will not affect the transmission and coupling relationship of ultrasonic waves in the reflection path. By setting the ultrasonic channel calibration test block to reflect reflected waves of different preset sound ranges, and determining the gain value difference of the signal amplification gain value of the first amplified signal of the specified sound range reflected wave of different ultrasonic channels, the calibration process of the signal amplification gain value between different ultrasonic channels can be quantified, and standardized calibration of the transmission characteristics of different ultrasonic channels can be achieved. This not only improves the calibration accuracy of the ultrasonic channel of the rail flaw detection system, but also avoids the inevitable occurrence of calibration errors due to manual adjustment, and at the same time improves the calibration efficiency of the ultrasonic channel of the rail flaw detection system.

[0064] At present, for ultrasonic transmitting and receiving circuit boards, the signal transmission characteristics of the ultrasonic transmitting and signal amplifying circuits need to be calibrated when the circuit boards leave the factory. However, after the boards are installed in the rail flaw detection vehicle, due to the high integration of the electronic cabinet and the limited space inside the vehicle, it is not easy to disassemble the boards for ultrasonic channel calibration. Moreover, the transmission characteristics of the ultrasonic channel are not only the calibration of the circuit board. The impedance difference after the circuit board and the cable are combined, the signal transmission length, and the cable arrangement will also have an impact on the signal transmission characteristics. The present application can solve the above problems. By setting the ultrasonic channel calibration test block to reflect the reflected waves of different preset sound ranges, and determining the gain value difference of the signal amplification gain value of the first amplified signal of the specified sound range reflected wave of different ultrasonic channels, the calibration process of the signal amplification gain value between different ultrasonic channels can be quantified. There is no need to disassemble the electronic cabinet of the rail flaw detection system. The ultrasonic channel calibration can be quickly realized when the rail flaw detection vehicle is parked, which is flexible and convenient to use.

[0065] In one embodiment, the ultrasonic channel calibration test block is connected to a wheel probe line connector of a wheel probe of a rail flaw detection vehicle.

[0066] In the above embodiment, the rail flaw detection vehicle can be kept parked first, and the wheel probe line connector of the wheel probe can be unplugged at the wheel probe support mechanism under the vehicle, and the wheel probe line can be installed on the cable of the ultrasonic channel calibration test block to achieve the connection between the ultrasonic channel calibration test block and the rail flaw detection vehicle.

[0067] In one embodiment, each ultrasonic channel of the rail flaw detection system performs the same gate parameter configuration and hardware parameter configuration.

[0068] In the above embodiment, since the ultrasonic channel calibration block can generate multiple reflection waves with a fixed sound path, the ultrasonic channels require consistent hardware configuration parameters (such as the system hardware parameter settings for ultrasonic channel calibration shown in Table 3) and gate position parameters (such as the gate parameter settings for ultrasonic channel calibration shown in Table 4):

[0069] Table 3

[0070] Serial number Ultrasound channel Transmission delay time In-wheel sound path difference 1 0° 0 0 2 37° 0 0 3 Straight 70° 0 0 4 70° tilt 0 0

[0071] Table 4

[0072] Serial number gate Gate Delay Gate width 1 0° interface 5 1 2 0° monitoring 1 200 3 0° bottom wave 1 200 4 70° external monitoring 1 200 5 Middle 70° monitoring 1 200 6 70° monitoring within 1 200 7 37° surveillance 1 200 8 37° rail bottom 1 200 9 C-type probe wheel 0° interface 5 1 10 C-type probe wheel 0° bottom wave 1 200 11 70° oblique monitoring 1 200

[0073] In one embodiment, each ultrasonic channel in the rail flaw detection system is specifically used to:

[0074] By adjusting the gate gain value, the received reflected waves of different preset sound ranges are amplified so that the wave height of the amplified reflected waves reaches the preset value, and the processed amplified signal is obtained.

[0075] In the above embodiment, each ultrasonic channel can use the same transducer and fixed reflector (i.e., the ultrasonic channel calibration test block). By comparing the gain difference at the same echo height, the comprehensive performance result conversion relationship between the channels can be calibrated.

[0076] Making the wave height of the reflected wave after signal amplification processing reach a preset value may include: making the wave height of the reflected wave after signal amplification processing reach the ultrasonic channel calibration point, and the ultrasonic channel calibration point may be: taking the second echo when the sound range is 100us as the reference echo, and making the echo height a gain value when it is 80% of the full amplitude.

[0077] During specific implementation, the reflected wave processing unit is used to obtain a first amplified signal of a reflected wave corresponding to a specified sound path from each ultrasonic channel; determine a signal amplification gain value of the first amplified signal of each ultrasonic channel; and calculate, for each ultrasonic channel, a difference between the signal amplification gain value of the first amplified signal of the ultrasonic channel and the signal amplification gain value of the first amplified signals of other ultrasonic channels.

[0078] In the above embodiment, by using the ultrasonic channel calibration block, the gain values of the ultrasonic channels of the flaw detection system at the same echo height can be calibrated, and the gain value differences between the channels can be calculated.

[0079] For example, if the gate gain value is S, then the gain difference ΔS between the channels is S 通道1 -S 通道2 , the maximum gain difference between channels ΔS max is max(S 通道n -S 通道m ).

[0080] In one embodiment, each ultrasonic channel in the rail flaw detection system is specifically used to:

[0081] By adjusting the gate gain value, the received reflected waves of different preset sound ranges are amplified so that the wave height of the amplified reflected waves reaches the preset value, and the processed amplified signal is obtained.

[0082] In the above embodiment, by adjusting the gate gain value, the reflected wave (i.e., the reflected echo) with a sound path of 100us can reach a wave height of 80%. For example, Figure 8 As shown, Figure 8 Displays the reference echoes of different ultrasonic channel calibrations (i.e., the height of the reflected wave after signal amplification reaches the preset value).

[0083] In one embodiment, it further includes:

[0084] An alarm unit is configured to determine a maximum value of a gain value difference from the signal amplification gain values of the first amplified signals of different ultrasound channels and the gain value differences between the signal amplification gain values of the first amplified signals of other ultrasound channels;

[0085] When the maximum value is greater than a preset value, an alarm message is issued indicating that an error exists in the ultrasonic channel of the rail flaw detection system.

[0086] In the above embodiment, the smaller the gain difference between the ultrasonic channels of the flaw detection system is, the better the consistency between the ultrasonic channels is. This difference has a minimum value requirement, such as requiring the maximum gain difference ΔS between ultrasonic channels of the same frequency in the rail flaw detection system. max ≤6dB.

[0087] In a specific implementation, the ultrasonic channel calibration unit is used to calibrate the signal amplification gain values of different ultrasonic channels according to the corresponding gain value differences when rail flaw detection is performed in different ultrasonic channels.

[0088] In the above embodiment, the purpose of ultrasonic channel calibration (i.e., ultrasonic channel comparison) is to calibrate the signal transmission characteristics of the ultrasonic channel, so that the technical parameters of the wheel probe (such as sensitivity margin, wave travel distance gain value, etc.) can be converted and transferred between ultrasonic channels, thereby achieving the purpose of normalizing the detection parameters of the rail flaw detection system.

[0089] In the embodiment, the ultrasound channel calibration unit is specifically used to:

[0090] For a first ultrasonic channel and a second ultrasonic channel used for rail flaw detection using the same wheel probe, recording a first signal amplification gain value of the first ultrasonic channel;

[0091] Obtain a first gain value difference corresponding to the first ultrasonic channel and the second ultrasonic channel;

[0092] The sum of the first signal amplification gain value of the first ultrasonic channel and the difference between the first gain values is used as the first signal amplification gain value of the second ultrasonic channel.

[0093] In one embodiment, when the same wheel probe is used on different ultrasonic transmitting and receiving analog circuit boards, the gain parameter can be detected and derived and converted according to the ultrasonic channel gain difference ΔS.

[0094] For example, if the gain value of wheel probe 1 when used on analog card 1 is S1, and the gain difference between the ultrasound channels of board 1 and board 2 is ΔS, then the gain value of wheel probe 1 when used on analog card 2 needs to be set to S1+ΔS.

[0095] In the above-mentioned embodiment, the key of the embodiment of the present invention is that the ultrasonic channel calibration test block includes a unified ultrasonic transducer and a reflector with a stable coupling relationship and a fixed sound path. By directly replacing the wheel probe under the rail flaw detection vehicle, the overall performance calibration of the ultrasonic transmission circuit characteristics, cable transmission characteristics, and signal receiving and conditioning circuit combination between each ultrasonic channel of the flaw detection system can be quickly completed, and the difference in signal amplification characteristics between the ultrasonic channels can be obtained, which facilitates the determination of the technical status of the system's ultrasonic channels and quickly realizes the normalization of detection parameters.

[0096] A specific embodiment is given below to illustrate the specific application of the system of the present invention, which is described in detail as follows:

[0097] 1. The system example of the present invention provides an ultrasonic channel calibration test block, which is composed of a fixed frequency ultrasonic transducer, an ultrasonic attenuation material, an ultrasonic reflective surface, a sound absorbing material, a cable plug, and a shell. Figure 7 As shown; Figure 4 As shown, Figure 4 An ultrasonic channel calibration test block group consisting of multiple ultrasonic channel calibration test blocks is presented. The ultrasonic channel calibration test block group can consist of 6 ultrasonic channel calibration test blocks.

[0098] 2. The system example of the present invention can be operated according to the following steps:

[0099] 1) Prepare the rail flaw detection system to be calibrated and the ultrasonic channel calibration test block mentioned above;

[0100] 2) Set the hardware parameters of the rail flaw detection system. Since the ultrasonic channel calibration block can generate multiple reflection waves with a fixed sound path, the ultrasonic channels need to have consistent hardware configuration parameters (see Table 3) and gate position parameters (see Table 4):

[0101] 3) Set the parameters of the flaw detection system according to Table 3 and Table 4. After the rail flaw detection system is initialized successfully, you can start the test;

[0102] 4) Keep the rail flaw detection vehicle parked, unplug the wheel probe cable connector of the wheel probe at the wheel probe support mechanism under the vehicle, and install the wheel probe cable on the cable of the ultrasonic channel calibration test block;

[0103] 5) Adjust the gate gain value of the rail flaw detection system so that the reflected echo within the 100us sound path can reach 80% wave height, see Figure 8 .

[0104] 6) If the gate gain value is set to S, then the gain difference ΔS between the channels is S 通道1 -S 通道2 , the maximum gain difference between channels ΔS max is max(S 通道n -S 通道m ).

[0105] 3. The system example of the present invention can technically achieve the following two requirements:

[0106] 1) Calibration qualification technical requirements: Maximum gain difference ΔS between ultrasonic channels of the same frequency in the rail flaw detection system max ≤6dB;

[0107] 2) Technical Requirements for Normalizing Test Parameters: When the same wheel probe is used on different ultrasonic transmitter and receiver analog boards, the test gain parameter is derived and converted based on the ultrasonic channel gain difference, ΔS. For example, if the gain of wheel probe 1 when used on analog board 1 is S1, and the ultrasonic channel gain difference between boards 1 and 2 is ΔS, the gain of wheel probe 1 when used on analog board 2 must be set to S1 + ΔS.

[0108] The key technical point of the system example of the present invention is that the ultrasonic channel calibration test block contains both a unified ultrasonic transducer and a reflector with a stable coupling relationship and a fixed sound range. By directly replacing the wheel probe under the rail flaw detection vehicle, the overall performance calibration of the ultrasonic transmission circuit characteristics, cable transmission characteristics, and signal reception and conditioning circuit combination between each ultrasonic channel of the flaw detection system can be quickly completed. The difference in signal amplification characteristics between the ultrasonic channels is obtained, which facilitates the determination of the technical status of the system's ultrasonic channels and quickly realizes the normalization of detection parameters.

[0109] The system example of the present invention can quickly implement ultrasonic channel calibration when the rail flaw detection vehicle is parked, without disassembling the electronic cabinet of the rail flaw detection system, and is flexible and convenient to use.

[0110] The embodiments of the present invention creatively propose: (1) a design method for an ultrasonic channel calibration test block, which includes selecting an attenuation material with a suitable sound velocity and customizing the length according to the sound path requirements of the flaw detection system; a design method for the sound absorbing material on both walls of the attenuation material; a method for matching the test block channel frequency and number with the flaw detection system; (2) an ultrasonic channel calibration method, which uses a channel calibration test block to calibrate the gain values of each ultrasonic channel of the flaw detection system at the same echo height and calculate the gain difference between the channels; (3) an ultrasonic channel signal transmission characteristic discrimination method, which calibrates the signal transmission characteristics of the ultrasonic channel so that the technical parameters of the wheel probe (such as sensitivity margin, travel distance gain value, etc.) can be converted and transmitted between the ultrasonic channels to achieve the purpose of normalizing the detection parameters of the rail flaw detection system; (4) a detection parameter normalization method, which derives and converts the detection gain parameters according to the ultrasonic channel gain difference ΔS when the same wheel probe is used on different ultrasonic transmitting and receiving analog circuit boards. For example, if the gain value of wheel probe 1 when used on analog card 1 is S1, and the difference in ultrasound channel gain between board 1 and board 2 is ΔS, then the gain value of wheel probe 1 when used on analog card 2 needs to be set to S1+ΔS.

[0111] Of course, it is understandable that the above detailed process may have other variations, and all relevant variations should fall within the scope of protection of the present invention.

[0112] In an embodiment of the present invention, an ultrasonic channel calibration test block is used to generate ultrasonic waves in response to an excitation signal of a rail flaw detection system; perform multiple attenuation reflections on the ultrasonic waves to generate reflected waves of different preset sound ranges; reflect the reflected waves of different preset sound ranges to each ultrasonic channel of the rail flaw detection system; each ultrasonic channel in the rail flaw detection system is used to perform signal amplification processing on the received reflected waves of different preset sound ranges to obtain a processed amplified signal; a reflected wave processing unit is used to obtain a first amplified signal corresponding to the reflected wave of a specified sound range from each ultrasonic channel; determine a signal amplification gain value of the first amplified signal of each ultrasonic channel; and calculate, for each ultrasonic channel, the signal amplification gain value of the first amplified signal of the ultrasonic channel and the gain of the signal amplification gain value of the first amplified signal of other ultrasonic channels. value difference; an ultrasonic channel calibration unit, which is used to calibrate the signal amplification gain values of different ultrasonic channels according to the corresponding gain value differences when performing rail flaw detection in different ultrasonic channels. Compared with the technical solutions in the prior art that require manual calibration of the ultrasonic channels, by setting the ultrasonic channel calibration test blocks to reflect reflected waves of different preset sound ranges, and determining the gain value differences of the signal amplification gain values of the first amplified signals of the reflected waves of the specified sound ranges in different ultrasonic channels, the calibration process of the signal amplification gain values between different ultrasonic channels can be quantified, and the standardized calibration of the transmission characteristics of different ultrasonic channels can be achieved. This not only improves the calibration accuracy of the ultrasonic channels of the rail flaw detection system, but also avoids the inevitable calibration errors due to manual adjustment, and at the same time improves the calibration efficiency of the ultrasonic channels of the rail flaw detection system.

[0113] The embodiment of the present invention further provides a calibration method for an ultrasonic channel of a rail flaw detection system, which is applied to the calibration system for the ultrasonic channel of a rail flaw detection system as described above. The calibration system for the ultrasonic channel of a rail flaw detection system is applied to a rail flaw detection vehicle to achieve standardized calibration of the ultrasonic channel of the rail flaw detection system, thereby improving the calibration accuracy and calibration efficiency of the ultrasonic channel of the rail flaw detection system. Figure 9 As shown, the method includes:

[0114] Step 901: The ultrasonic channel calibration test block generates ultrasonic waves in response to an excitation signal of a rail flaw detection system; performs multiple attenuation reflections on the ultrasonic waves to generate reflected waves of different preset sound ranges; reflects the reflected waves of different preset sound ranges toward each ultrasonic channel of the rail flaw detection system; and each ultrasonic channel of the rail flaw detection system amplifies the received reflected waves of different preset sound ranges to obtain processed amplified signals.

[0115] Step 902: The reflected wave processing unit obtains a first amplified signal corresponding to a reflected wave in a specified sound path from each ultrasonic channel; determines a signal amplification gain value of the first amplified signal of each ultrasonic channel; and calculates, for each ultrasonic channel, a gain difference between the signal amplification gain value of the first amplified signal of the ultrasonic channel and the signal amplification gain values of the first amplified signals of other ultrasonic channels.

[0116] Step 903: When performing rail flaw detection in different ultrasonic channels, the ultrasonic channel calibration unit calibrates the signal amplification gain values of different ultrasonic channels according to the corresponding gain value differences.

[0117] In one embodiment, it further includes:

[0118] The alarm unit determines a maximum value of the gain value difference from the signal amplification gain values of the first amplified signals of different ultrasound channels and the gain value differences between the signal amplification gain values of the first amplified signals of other ultrasound channels;

[0119] When the maximum value is greater than a preset value, an alarm message is issued indicating that an error exists in the ultrasonic channel of the rail flaw detection system.

[0120] In an embodiment of the present invention, an ultrasonic channel calibration test block is used to generate ultrasonic waves in response to an excitation signal of a rail flaw detection system; perform multiple attenuation reflections on the ultrasonic waves to generate reflected waves of different preset sound ranges; reflect the reflected waves of different preset sound ranges to each ultrasonic channel of the rail flaw detection system; each ultrasonic channel in the rail flaw detection system is used to perform signal amplification processing on the received reflected waves of different preset sound ranges to obtain a processed amplified signal; a reflected wave processing unit is used to obtain a first amplified signal corresponding to the reflected wave of a specified sound range from each ultrasonic channel; determine a signal amplification gain value of the first amplified signal of each ultrasonic channel; and calculate, for each ultrasonic channel, the signal amplification gain value of the first amplified signal of the ultrasonic channel and the gain of the signal amplification gain value of the first amplified signal of other ultrasonic channels. value difference; an ultrasonic channel calibration unit, which is used to calibrate the signal amplification gain values of different ultrasonic channels according to the corresponding gain value differences when performing rail flaw detection in different ultrasonic channels. Compared with the technical solutions in the prior art that require manual calibration of the ultrasonic channels, by setting the ultrasonic channel calibration test blocks to reflect reflected waves of different preset sound ranges, and determining the gain value differences of the signal amplification gain values of the first amplified signals of the reflected waves of the specified sound ranges in different ultrasonic channels, the calibration process of the signal amplification gain values between different ultrasonic channels can be quantified, and the standardized calibration of the transmission characteristics of different ultrasonic channels can be achieved. This not only improves the calibration accuracy of the ultrasonic channels of the rail flaw detection system, but also avoids the inevitable calibration errors due to manual adjustment, and at the same time improves the calibration efficiency of the ultrasonic channels of the rail flaw detection system.

[0121] It will be understood by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0122] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts and / or block diagrams. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0123] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0124] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0125] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A calibration system for an ultrasonic channel of a rail flaw detection system, characterized in that: Applied to rail flaw detection vehicles, the system includes: The ultrasonic channel calibration test block is configured to generate ultrasonic waves in response to an excitation signal of a rail flaw detection system; perform multiple attenuation reflections on the ultrasonic waves to generate reflected waves of different preset sound ranges; and reflect the reflected waves of different preset sound ranges toward each ultrasonic channel of the rail flaw detection system; and each ultrasonic channel of the rail flaw detection system is configured to amplify the received reflected waves of different preset sound ranges to obtain processed amplified signals. a reflected wave processing unit configured to obtain, from each ultrasonic channel, a first amplified signal corresponding to a reflected wave in a specified sound path; determine a signal amplification gain value for the first amplified signal of each ultrasonic channel; and calculate, for each ultrasonic channel, a difference between the signal amplification gain value of the first amplified signal of the ultrasonic channel and the signal amplification gain values of the first amplified signals of other ultrasonic channels; The ultrasonic channel calibration unit is used to calibrate the signal amplification gain values of different ultrasonic channels according to the corresponding gain value differences when performing rail flaw detection on different ultrasonic channels; The ultrasonic channel calibration unit is specifically used to: record the first signal amplification gain value of the first ultrasonic channel and the second ultrasonic channel for rail flaw detection using the same wheel probe; obtain the difference between the first gain values of the first ultrasonic channel and the second ultrasonic channel; and use the sum of the first signal amplification gain value of the first ultrasonic channel and the difference between the first gain values as the first signal amplification gain value of the second ultrasonic channel.

2. The system according to claim 1, wherein Ultrasonic channel calibration test block, including: An ultrasonic emitting device, an ultrasonic attenuation device attached to the ultrasonic emitting end of the ultrasonic emitting device, and an ultrasonic reflecting device connected to one end of the ultrasonic attenuation device; An ultrasonic transmitter, used to generate ultrasonic waves in response to an excitation signal from a rail flaw detection system; The ultrasonic attenuation device and the ultrasonic reflection device are used to perform multiple attenuation and reflection on the ultrasonic wave to generate reflected waves with different preset sound ranges.

3. The system according to claim 2, wherein: Ultrasonic channel calibration test block, also includes: Sound-absorbing material device, used to prevent the ultrasonic sound beam from reflecting on the cylinder wall to form delayed waves; Cable and plug assembly for connecting to rail flaw detection system; The shell is used to protect the ultrasonic emitting device, the ultrasonic attenuation device, the ultrasonic reflecting device and the sound absorbing material device.

4. The system according to claim 1, wherein The ultrasonic channel calibration test block is connected to the wheel detection line connector of the wheel probe of the rail flaw detection vehicle.

5. The system according to claim 1, wherein: Each ultrasonic channel of the rail flaw detection system performs the same gate parameter configuration and hardware parameter configuration.

6. The system according to claim 1, wherein: Each ultrasonic channel in the rail flaw detection system is specifically used for: By adjusting the gate gain value, the received reflected waves of different preset sound ranges are amplified so that the wave height of the amplified reflected waves reaches the preset value, and the processed amplified signal is obtained.

7. The system according to claim 1, wherein: Also includes: An alarm unit is configured to determine a maximum value of a gain value difference from the signal amplification gain values of the first amplified signals of different ultrasound channels and the gain value differences between the signal amplification gain values of the first amplified signals of other ultrasound channels; When the maximum value is greater than a preset value, an alarm message is issued indicating that an error exists in the ultrasonic channel of the rail flaw detection system.

8. A method for calibrating an ultrasonic channel of a rail flaw detection system, characterized in that: A calibration system for an ultrasonic channel of a rail flaw detection system according to any one of claims 1 to 7, wherein the calibration system for an ultrasonic channel of a rail flaw detection system is applied to a rail flaw detection vehicle, the method comprising: The ultrasonic channel calibration test block generates ultrasonic waves in response to an excitation signal of the rail flaw detection system; performs multiple attenuation reflections on the ultrasonic waves to generate reflected waves of different preset sound ranges; reflects the reflected waves of different preset sound ranges toward each ultrasonic channel of the rail flaw detection system; and each ultrasonic channel of the rail flaw detection system is configured to amplify the received reflected waves of different preset sound ranges to obtain processed amplified signals. The reflected wave processing unit obtains a first amplified signal corresponding to a reflected wave in a specified sound path from each ultrasonic channel; determines a signal amplification gain value of the first amplified signal of each ultrasonic channel; and calculates, for each ultrasonic channel, a gain difference between the signal amplification gain value of the first amplified signal of the ultrasonic channel and the signal amplification gain values of the first amplified signals of other ultrasonic channels; When the ultrasonic channel calibration unit performs rail flaw detection in different ultrasonic channels, the signal amplification gain values of the different ultrasonic channels are calibrated according to the corresponding gain value differences.

9. The method according to claim 8, wherein Also includes: The alarm unit determines a maximum value of the gain value difference from the signal amplification gain values of the first amplified signals of different ultrasound channels and the gain value differences between the signal amplification gain values of the first amplified signals of other ultrasound channels; When the maximum value is greater than a preset value, an alarm message is issued indicating that an error exists in the ultrasonic channel of the rail flaw detection system.

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