An unevenness detection system for tracks, a detection method, and a metrological calibration method

Abstract

The present invention discloses a track vertical irregularity detection system, a detection method, and a metrological calibration method. The detection system is installed on a detection train and includes a control system, a power supply module, a triaxial accelerometer I, a triaxial accelerometer II, a pressure sensor I, a pressure sensor II, and a non-contact displacement detection device: The detection train includes a car body, a bogie, and wheels. The wheels include front and rear wheels; The car body is connected to the bogie through a secondary suspension system, and the bogie is connected to the wheels through a primary suspension system; The triaxial accelerometer I and the pressure sensor I are respectively arranged at the top and bottom of the spring of the primary suspension system of the front wheels; The triaxial accelerometer II and the pressure sensor II are respectively arranged at the top and bottom of the spring of the primary suspension system of the rear wheels; The non-contact displacement detection device is arranged at the central axis position of the bogie. The present invention can achieve more accurate detection of track vertical irregularities and can achieve on-line metrological calibration of the original track inspection system.

Description

Technical Field

[0001] The present invention relates to the technical field of rail transit equipment measurement and detection, and particularly relates to a track vertical irregularity detection system, a detection method, and a metrological calibration method. Background Art

[0002] Track vertical irregularity refers to the unevenness of a railway track in the longitudinal direction, that is, the height of the track has irregular undulations. Such irregularities may be caused by problems in track laying quality, foundation settlement, aging of track materials, or other environmental factors. The vertical irregularity of the track will cause vibrations and shakes during the train's operation, and even increase the risk of derailment. The vertical irregularity of the track has an important impact on the safety of railway transportation and the comfort of passengers. Therefore, high-precision detection of track vertical irregularity is extremely important.

[0003] For the detection of track vertical irregularity, in China, generally an inertial navigation system or a two-dimensional laser sensor is used as the mainstay. The inertial navigation system mainly uses an inertial basic unit, i.e., a three-axis accelerometer, to measure the acceleration of the bogie in real time, and then performs a second integration on the acceleration to obtain the displacement value in the vertical direction of the track. Then, by adding the displacement value measured by a one-dimensional laser sensor as a reference, the final vertical irregularity value is obtained. This method can usually reflect the deformation trend of the track more accurately. However, the traditional track inspection system using the inertial reference method often does not consider the influence of the different compression amounts of the primary suspension system during the actual operation of the track inspection system on the measurement data of the three-axis accelerometer, and thus does not perform corresponding compensation processing, resulting in the measurement accuracy and accuracy often not meeting the requirements.

[0004] In addition, not only is the detection of track vertical irregularity extremely important, but also the on-line metrological calibration of traffic equipment for track detection is crucial. Because it is indirectly related to the safety, comfort, and efficiency of railway transportation. By regularly maintaining the detection systems at key positions, the accuracy problems of the detection systems can be discovered and repaired in a timely manner. The detection systems detect each key point of the track and use this as the standard for whether to perform maintenance, which can reduce the risks of vibrations, impacts, and derailment during train operation, reduce equipment wear, and optimize the operation efficiency. Thereby ensuring the safety and comfort of passengers, extending the service life of related equipment, and reducing the maintenance cost. Therefore, the operating state of the track detection system directly determines the safe operation of the train. So, in order to ensure national property and people's lives and safety, the rail detection system needs to be calibrated regularly to verify the accuracy of the detection system itself, measure various geometric parameters of the rail more accurately, and ensure the safety and stability of train operation.

[0005] For the metrological calibration of detection equipment, currently, the detection systems for tracks and catenaries in the domestic and international rail transit industries are generally non-detachable. The traditional calibration method is to disassemble key sensors of the detection system, such as displacement sensors and accelerometers, and send them to a metrological calibration institution for inspection. This method has a series of problems, such as a long calibration cycle, inaccurate calibration data caused by the deviation between the calibration environment and the actual use environment, and inapplicability. Summary of the Invention

[0006] In view of the above problems, the present invention aims to provide a track unevenness detection system, a detection method, and a metrological calibration method.

[0007] The technical solution of the present invention is as follows:

[0008] On the one hand, a track unevenness detection system is provided, which is installed on a detection train and includes a control system, a power supply module, a first three-axis accelerometer, a second three-axis accelerometer, a first pressure sensor, a second pressure sensor, and a non-contact displacement detection device that are respectively connected to the control system:

[0009] The detection train includes a car body, a bogie, and wheels. The wheels include front wheels and rear wheels; the car body is connected to the bogie through a secondary suspension system, and the bogie is connected to the wheels through a primary suspension system;

[0010] The first three-axis accelerometer and the first pressure sensor are respectively arranged at the top and bottom of the spring of the primary suspension system of the front wheels;

[0011] The second three-axis accelerometer and the second pressure sensor are respectively arranged at the top and bottom of the spring of the primary suspension system of the rear wheels;

[0012] The non-contact displacement detection device is arranged at the central axis position of the bogie.

[0013] Preferably, both the first pressure sensor and the second pressure sensor adopt high-pressure pressure sensors.

[0014] Preferably, the non-contact displacement detection device adopts a one-dimensional laser sensor.

[0015] Preferably, the control system includes a host computer and a microcontroller that are connected.

[0016] On the other hand, a track unevenness detection method is also provided, which uses the track unevenness detection system described in any one of the above to perform detection. The track unevenness detection method includes the following steps:

[0017] S1: When the detection train is stationary, detect the static pressure value F1 of the primary suspension system at this time through the first pressure sensor, and detect the static pressure value F2 of the primary suspension system at this time through the second pressure sensor;

[0018] Start the detection train, detect the dynamic pressure value F1(t) of the primary suspension system through the first pressure sensor, and detect the dynamic pressure value F2(t) of the primary suspension system through the second pressure sensor;

[0019] Detect the acceleration value a1 of the detection train through the first triaxial accelerometer, and detect the acceleration value a2 of the detection train through the second triaxial accelerometer;

[0020] Detect the displacement reference value w3 through the non-contact displacement detection device;

[0021] S2: Calculate the dynamic transformation value ΔF1(t) with time as the independent variable according to the static pressure value F1 and the dynamic pressure value F1(t), and calculate the dynamic transformation value ΔF2(t) with time as the independent variable according to the static pressure value F2 and the dynamic pressure value F2(t);

[0022] S3: Calculate the dynamic compression amount Δl1 of the primary suspension system during the detection process according to the dynamic transformation value ΔF1(t) combined with the elastic coefficient k of the primary suspension system, and calculate the dynamic compression amount Δl2 of the primary suspension system during the detection process according to the dynamic transformation value ΔF2(t) combined with the elastic coefficient k of the primary suspension system;

[0023] S4: Perform second-order integration processing on the acceleration value a1 and the acceleration value a2 respectively to obtain the uncompensated displacement value w1 and the displacement value w2;

[0024] S5: Calculate the vertical irregularity result w according to the displacement value w1 combined with the displacement reference value w3 13 , calculate the vertical irregularity result w according to the displacement value w2 combined with the displacement reference value w3 23 ;

[0025] S6: Compensate the vertical irregularity result w 13 with the dynamic compression amount Δl1 to obtain the compensation result h1, and compensate the vertical irregularity result w 23 with the dynamic compression amount Δl2 to obtain the compensation result h2;

[0026] S7: Average the compensation result h1 and the compensation result h2 to calculate and obtain the final track vertical irregularity detection value.

[0027] Preferably, in step S2, each dynamic transformation value is calculated through the following formula:

[0028] ΔF1(t) = F1(t) - F1(1)

[0029] ΔF2(t) = F2(t) - F2(2)

[0030] In step S3, each dynamic compression amount is calculated respectively by the following formula:

[0031]

[0032] In step S4, each displacement value is calculated respectively by the following formula:

[0033] w1 = ∫∫a1dt (5)

[0034] w2 = ∫∫a2dt (6)

[0035] In step S5, each roughness result is calculated respectively by the following formula:

[0036] w 13 = w1 + w3 + Δh (7)

[0037] w 23 = w2 + w3 + Δh (8)

[0038] Where: Δh is the displacement difference between the non-contact displacement detection device and the triaxial accelerometer in the vertical direction;

[0039] In step S6, each compensation result is calculated respectively by the following formula:

[0040] h1 = Δl1 + w 13 (9)

[0041] h2 = Δl2 + w 23 (10).

[0042] On the other hand, a method for metrological calibration of a track roughness detection system is also provided, including the following steps:

[0043] Using the track roughness detection system described in any one of the above or the track roughness detection method described in any one of the above to detect the track to obtain the track roughness detection value after data compensation;

[0044] Using the original track roughness detection system to detect the track to obtain the original track roughness detection value;

[0045] Using the track roughness detection value after data compensation to perform metrological calibration on the original track roughness detection value.

[0046] The beneficial effects of the present invention are:

[0047] (1) The present invention combines the arrangement position of the triaxial accelerometer with the primary suspension system, installs the non-contact displacement detection device at the central axis position of the bogie, and uses the measured value directly above the track as the displacement reference value, which can effectively solve the uncertainty problem brought by the primary suspension system to the track inspection system's method of measuring vertical irregularities based on the deformation of the suspension system.

[0048] (2) After solving the uncertainty brought by the primary suspension system through the triaxial accelerometer arrangement method, the present invention adopts a technical solution that combines the pressure sensor with the primary suspension system, completes the standard measurement of the uncertainty of the primary suspension system, and greatly improves the theoretical measurement accuracy of the method for measuring vertical irregularities by the track inspection system based on the deformation of the suspension system.

[0049] (3) The present invention has the advantages of being easy to disassemble and high precision. According to the present invention, on-line dynamic metrological calibration can also be realized without disassembling the original system, solving the problem that the original detection system cannot be disassembled and thus cannot be metrologically calibrated.

[0050] (4) In the algorithm of each parameter in the method for detecting track vertical irregularities of the present invention, compared with the traditional algorithm, the anti-interference ability is stronger, which can effectively reduce the random error in the dynamic detection process and improve the detection accuracy of the whole system. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] 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 following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0052] Figure 1 is the front view structural schematic diagram of the track vertical irregularity detection system of the present invention;

[0053] Figure 2 is the left view structural schematic diagram of the track vertical irregularity detection system of the present invention;

[0054] Figure 3 is the flow schematic diagram of the method for detecting track vertical irregularities of the present invention.

[0055] Reference numerals in the drawings: 1 - power supply module, 2 - triaxial accelerometer one, 3 - triaxial accelerometer two, 4 - pressure sensor one, 5 - pressure sensor two, 6 - non-contact displacement detection device, 7 - car body, 8 - bogie, 9 - wheel, 10 - secondary suspension system, 11 - primary suspension system, 12 - upper computer, 13 - microcontroller. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0056] The present invention will be further described below in conjunction with the accompanying drawings and embodiments. It should be noted that, without conflict, the embodiments in the present application and the technical features in the embodiments may be combined with each other. It should be pointed out that, unless otherwise specified, all technical and scientific terms used in the present application have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present application belongs. The terms "including" or "comprising" and the like used in the disclosure of the present invention mean that the elements or objects appearing before the term cover the elements or objects listed after the term and their equivalents, without excluding other elements or objects.

[0057] On the one hand, as Figure 1-2 shown, the present invention provides a track irregularity detection system installed on a detection train, which includes a control system and a power supply module 1, a triaxial accelerometer 1 2, a triaxial accelerometer 2 3, a pressure sensor 1 4, a pressure sensor 2 5, and a non-contact displacement detection device 6 respectively connected to the control system:

[0058] The detection train includes a car body 7, a bogie 8, and wheels 9, and the wheels 9 include front wheels and rear wheels; the car body 7 is connected to the bogie 8 through a secondary suspension system 10, and the bogie 8 is connected to the wheels 9 through a primary suspension system 11;

[0059] The triaxial accelerometer 1 2 and the pressure sensor 1 4 are respectively arranged at the top and bottom of the spring of the primary suspension system 11 of the front wheels;

[0060] The triaxial accelerometer 2 3 and the pressure sensor 2 5 are respectively arranged at the top and bottom of the spring of the primary suspension system 11 of the rear wheels;

[0061] The non-contact displacement detection device 6 is arranged at the central axis position of the bogie 8.

[0062] It should be noted that when using the present invention, the track vertical irregularity detection system is installed on the same side of the inspection train. The non-contact displacement detection device installed at the central axis position of the bogie and the triaxial accelerometers above the front and rear primary suspension systems are used as the initial measurement data sources for two groups of methods for measuring vertical irregularity based on the deformation of the suspension system. The pressure sensors below the two primary suspension systems are used to measure the force on the primary suspension system under dynamic conditions; the difference between the dynamic value measured by the pressure sensor and the static value measured under static conditions is combined with the elastic coefficient of the primary suspension system to obtain the change in the compression amount of the primary suspension system under dynamic conditions; the obtained change in the compression amount is used as compensation data to compensate the measurement results of the method for measuring vertical irregularity based on the deformation of the suspension system at their respective positions to complete data compensation and correction; the average value of the two groups of data is used as the track vertical irregularity value of this track finally.

[0063] In the present invention, by combining the arrangement of the triaxial accelerometers of the inertial navigation system in the inertial reference method with the primary suspension system, the triaxial accelerometers and the primary suspension system are made to maintain vibration consistency in the vertical direction of the track, and the primary suspension system is combined with the pressure sensor. The displacement value measured by the one-dimensional laser sensor is compensated by the dynamic change amount of the primary suspension system measured by the pressure sensor, which can solve the uncertainty brought by the primary suspension system in the method for measuring vertical irregularity based on the deformation of the suspension system of the track inspection system. The final result adopts the average value of the two groups of data, which can reduce the random error in the measurement process, improve the data accuracy of the entire detection system, and realize high-precision measurement of vertical irregularity by the method for measuring vertical irregularity based on the deformation of the suspension system of the track inspection system. In addition, according to the measurement value of the present invention, the measurement value of the original system can also be fed back upward, thereby performing on-line metrological calibration of the original detection system.

[0064] In a specific embodiment, both the pressure sensor 4 and the pressure sensor 5 adopt high-pressure pressure sensors, and the non-contact displacement detection device 6 adopts a one-dimensional laser sensor.

[0065] It should be noted that the non-contact displacement detection device is a prior art. In the above embodiment, the one-dimensional laser sensor is only a preferred non-contact displacement detection device of the present invention, and its measurement accuracy is higher than that of the two-dimensional laser sensor.

[0066] In a specific embodiment, the control system includes a host computer 12 and a microcontroller 13 connected to each other.

[0067] On the other hand, as Figure 3As shown in the figure, the present invention also provides a method for detecting track unevenness, which uses the track unevenness detection system described in any one of the above to perform detection. The method for detecting track unevenness includes the following steps:

[0068] S1: When the detection train is stationary, the static pressure value F1 of the primary suspension system 11 is detected by the first pressure sensor 4 at this time, and the static pressure value F2 of the primary suspension system 11 is detected by the second pressure sensor 5 at this time;

[0069] Start the detection train, and detect the dynamic pressure value F1(t) of the primary suspension system 11 through the first pressure sensor 4, and detect the dynamic pressure value F2(t) of the primary suspension system 11 through the second pressure sensor 5;

[0070] Detect the acceleration value a1 of the detection train through the first triaxial accelerometer 2, and detect the acceleration value a2 of the detection train through the second triaxial accelerometer 3;

[0071] Detect the displacement reference value w3 through the non-contact displacement detection device 6;

[0072] S2: Calculate the dynamic transformation value ΔF1(t) with time as the independent variable according to the static pressure value F1 and the dynamic pressure value F1(t), and calculate the dynamic transformation value ΔF2(t) with time as the independent variable according to the static pressure value F2 and the dynamic pressure value F2(t); each dynamic transformation value is calculated through the following formula:

[0073] ΔF1(t) = F1(t) - F1 (1)

[0074] ΔF2(t) = F2(t) - F2 (2)

[0075] S3: Calculate the dynamic compression amount Δl1 of the primary suspension system during the detection process according to the dynamic transformation value ΔF1(t) combined with the elastic coefficient k of the primary suspension system, and calculate the dynamic compression amount Δl2 of the primary suspension system during the detection process according to the dynamic transformation value ΔF2(t) combined with the elastic coefficient k of the primary suspension system; each dynamic compression amount is calculated through the following formula:

[0076]

[0077] S4: Perform double integration processing on the acceleration value a1 and the acceleration value a2 respectively to obtain the uncompensated displacement value w1 and the displacement value w2; each displacement value is calculated through the following formula:

[0078] w1 = ∫∫a1dt (5)

[0079] w2 = ∫∫a2dt (6)

[0080] S5: Calculate the vertical irregularity result w based on the displacement value w1 in combination with the displacement reference value w3 13 , and calculate the vertical irregularity result w based on the displacement value w2 in combination with the displacement reference value w3 23 ; Each vertical irregularity result is calculated respectively by the following formula:

[0081] w 13 = w1 + w3 + Δh (7)

[0082] w 23 = w2 + w3 + Δh (8)

[0083] Where: Δh is the displacement difference between the non-contact displacement detection device and the triaxial accelerometer in the vertical direction;

[0084] S6: Compensate the vertical irregularity result w 13 using the dynamic compression amount Δl1 to obtain a compensation result h1, and compensate the vertical irregularity result w 23 using the dynamic compression amount Δl2 to obtain a compensation result h2; Each compensation result is calculated respectively by the following formula:

[0085] h1 = Δl1 + w 13 (9)

[0086] h2 = Δl2 + w 23 (10)

[0087] S7: Calculate the average of the compensation result h1 and the compensation result h2 to obtain the final track vertical irregularity detection value.

[0088] On the other hand, the present invention also provides a method for metrological calibration of a track vertical irregularity detection system, including the following steps:

[0089] Use the track vertical irregularity detection system described in any one of the above or the track vertical irregularity detection method described in any one of the above to detect the track to obtain the track vertical irregularity detection value after data compensation;

[0090] Use the original track vertical irregularity detection system to detect the track to obtain the original track vertical irregularity detection value;

[0091] Use the track vertical irregularity detection value after data compensation to perform metrological calibration on the original track vertical irregularity detection value.

[0092] In a specific embodiment, the detection results of the track roughness detection method of the present invention are respectively compared with the roughness values measured by the inertial reference method in the original inertial navigation system and the roughness values obtained from the scanning profile of the two-dimensional laser sensor by the comparison method. The high-precision measurement data after data compensation is compared with the low-precision measurement data without data reduction, and then the online dynamic accuracy of the original system is fed back, so as to complete the online metrological calibration of the original system without disassembly.

[0093] In summary, the present invention combines the method for detecting roughness based on the inertial reference method with a primary suspension system, and can obtain more accurate data results in cooperation with the pressure sensor. It not only realizes a more accurate measurement of track roughness by the track inspection system, but also can realize the online metrological calibration of the original system without disassembly. Compared with the prior art, the present invention has made remarkable progress.

[0094] The above are only the preferred embodiments of the present invention, and do not impose any form of limitation on the present invention. Although the present invention has been disclosed above with the preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to the equivalent embodiments by using the technical content disclosed above within the scope of the technical solution of the present invention. However, as long as it does not depart from the content of the technical solution of the present invention, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. An unevenness detection system for tracks, which is installed on a detection train, is characterized in that It includes a control system, a power supply module, a first triaxial accelerometer, a second triaxial accelerometer, a first pressure sensor, a second pressure sensor, and a non-contact displacement detection device, which are respectively connected to the control system: The detection train includes a car body, a bogie, and wheels. The wheels include front wheels and rear wheels. The car body is connected to the bogie through a secondary suspension system, and the bogie is connected to the wheels through a primary suspension system; The first triaxial accelerometer and the first pressure sensor are respectively arranged at the top and bottom of the spring of the primary suspension system of the front wheels; The second triaxial accelerometer and the second pressure sensor are respectively arranged at the top and bottom of the spring of the primary suspension system of the rear wheels; The non-contact displacement detection device is arranged at the central axis position of the bogie; Use the pressure sensors under the two primary suspension systems to measure the force on the primary suspension system under dynamic conditions. Subtract the dynamic value measured by the pressure sensor from the static value measured under static conditions, and then cooperate with the elastic coefficient of the primary suspension system to obtain the change in the compression amount of the primary suspension system under dynamic conditions. Use the obtained change in the compression amount as compensation data to compensate at their respective positions to complete data compensation and correction.

2. The track roughness detection system according to claim 1, characterized in that Both the first pressure sensor and the second pressure sensor adopt high-pressure pressure sensors.

3. The track roughness detection system according to claim 1, characterized in that The non-contact displacement detection device adopts a one-dimensional laser sensor.

4. The track unevenness detection system according to claim 1, characterized in that, The control system includes a host computer and a microcontroller connected to each other.

5. A method for detecting track vertical irregularity, characterized in that, Use the track vertical irregularity detection system described in any one of claims 1-4 for detection. The track vertical irregularity detection method includes the following steps: S1: When the detection train is stationary, detect the static pressure value F1 of the primary suspension system at this time through the first pressure sensor, and detect the static pressure value F2 of the primary suspension system at this time through the second pressure sensor; Start the detection train, detect the dynamic pressure value F1(t) of the primary suspension system through the first pressure sensor, and detect the dynamic pressure value F2(t) of the primary suspension system through the second pressure sensor; Detect the acceleration value a1 of the detection train through the first triaxial accelerometer, and detect the acceleration value a2 of the detection train through the second triaxial accelerometer; Detect the displacement reference value w3 through the non-contact displacement detection device; S2: Calculate the dynamic change value ΔF1(t) with time as the independent variable according to the static pressure value F1 and the dynamic pressure value F1(t), and calculate the dynamic change value ΔF2(t) with time as the independent variable according to the static pressure value F2 and the dynamic pressure value F2(t); S3: Calculate the dynamic compression amount Δl1 of the primary suspension system during the detection process according to the dynamic change value ΔF1(t) combined with the elastic coefficient k of the primary suspension system, and calculate the dynamic compression amount Δl2 of the primary suspension system during the detection process according to the dynamic change value ΔF2(t) combined with the elastic coefficient k of the primary suspension system; S4: Perform second-order integral processing on the acceleration value a1 and the acceleration value a2 respectively to obtain the uncompensated displacement value w1 and the displacement value w2; S5: Calculate the vertical irregularity result w based on the displacement value w1 in combination with the displacement reference value w3 13 , calculate the vertical irregularity result w based on the displacement value w2 in combination with the displacement reference value w3 23 ; S6: Compensate the unevenness result w according to the dynamic compression amount Δl1 13 to obtain a compensation result h1, and compensate the unevenness result w according to the dynamic compression amount Δl2 23 to obtain a compensation result h2; S7: Calculate the average of the compensation results h1 and h2 to obtain the final track vertical irregularity detection value.

6. The track roughness detection method according to claim 5, characterized in that, In step S2, each dynamic transformation value is calculated respectively by the following formula: （1） （2） In step S3, each dynamic compression amount is calculated respectively by the following formula: （3） （4） In step S4, each displacement value is calculated respectively by the following formula: （5） （6） In step S5, each vertical irregularity result is calculated respectively by the following formula: （7） （8） In the formula: Δh is the displacement difference in the vertical direction between the non-contact displacement detection device and the triaxial accelerometer; In step S6, each compensation result is calculated respectively by the following formula: （9） （10）。 7. A metrological calibration method for an orbital irregularity detection system, characterized in that, Including the following steps: Using the track vertical irregularity detection system described in any one of claims 1-4 or the track vertical irregularity detection method described in any one of claims 5-6 to detect the track to obtain the track vertical irregularity detection value after data compensation; Using the original track vertical irregularity detection system to detect the track to obtain the original track vertical irregularity detection value; Using the track vertical irregularity detection value after data compensation to perform metrological calibration on the original track vertical irregularity detection value.

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