Pantograph detection device

Abstract

The utility model relates to the field of rail transit, in particular to a pantograph detection device. The device comprises a calibration device and a camera unit, the calibration device is formed by splicing three identical calibration plates, the calibration plates on the two sides of the calibration device are perpendicular to the middle calibration plate, and the calibration plates on the two sides are not in contact and are opposite in the same direction; the camera unit comprises 2D camera groups and 3D cameras, the 3D cameras are arranged right above a middle calibration plate of the calibration device, and the 2D camera groups are respectively arranged on two sides of the calibration device and are consistent with the calibration plates on two sides of the calibration device in direction. More comprehensive detection data are obtained by calibrating the 3D camera and the 2D camera at the same time, the difficulty of unifying the coordinate system of the 2D camera and the 3D camera is simplified, the three-dimensional data trend and the two-dimensional data trend can be aligned after unifying the coordinate system, the stability of the three-dimensional data and the high-precision characteristic of the two-dimensional data are fully utilized, and the accuracy of the three-dimensional data and the two-dimensional data is improved. Therefore, high-precision and high-stability detection data can be obtained.

Description

Technical Field

[0001] The utility model relates to the field of rail transportation, in particular to a pantograph detection device. Background Art

[0002] In the field of rail transit, online detection of pantographs has gradually become a way to replace manual maintenance. The pantograph online detection system is mainly based on machine vision technology to dynamically detect the posture of the pantograph and the degree of wear of the carbon slide plate.

[0003] Existing pantograph detection technologies include three-dimensional detection technology, two-dimensional detection technology, and three-dimensional + two-dimensional detection technology. Among them, the three-dimensional detection technology has a more comprehensive detection range and strong anti-interference ability. However, due to the manufacturing error of the pantograph slide, although it can detect the thickness change trend of the carbon slide, it cannot accurately detect the absolute remaining thickness of the carbon slide. The two-dimensional detection technology can achieve high-precision detection of the remaining thickness of the carbon slide, but it is easily affected by light, rain, etc., and its stability is not as good as the three-dimensional detection technology. The combination of three-dimensional and two-dimensional detection methods often uses three-dimensional detection posture and two-dimensional detection of the remaining thickness of the slide. Since the camera coordinate system of the two-dimensional data and the three-dimensional data is inconsistent, the final data cannot be fused, and thus the high-precision characteristics of two-dimensional detection and the stability advantages of three-dimensional detection cannot be fully utilized. Utility Model Content

[0004] In view of this, the utility model provides a pantograph detection device and a detection method thereof, aiming to solve all or part of the above-mentioned technical problems.

[0005] In order to solve the above technical problems, the technical solution of the utility model is to provide a pantograph detection device, including: a calibration device and a camera unit, the calibration device is composed of three completely identical calibration plates, the calibration plates on both sides of the calibration device are arranged perpendicular to the middle calibration plate, and the calibration plates on both sides are non-contact and opposite to each other in the same direction; the camera unit includes a 2D camera group and a 3D camera, the 3D camera is arranged directly above the middle calibration plate of the calibration device, and is used for three-dimensional image acquisition, and the 2D camera group is respectively arranged on both sides of the calibration device, and is consistent with the direction of the calibration plates on both sides of the calibration device, and is used for two-dimensional image acquisition.

[0006] As an implementation manner, the 2D camera group includes at least four 2D cameras, and the number of 2D cameras on both sides is the same.

[0007] As an implementation manner, it further includes a flashlight group, which includes at least four flashlights. The four flashlights are respectively arranged on the inner side of the relative position of the 2D camera, and the horizontal height is consistent with the horizontal height of the 2D camera.

[0008] As an implementation manner, the 2D camera group is arranged at a level higher than the level of the upper surface of the calibration device, and is used for capturing two-dimensional images of the upper surface and side surfaces of the calibration device.

[0009] As an implementation manner, the 3D camera is set at a higher level than the 2D camera group, and is used for collecting three-dimensional images of the upper surface of the calibration device.

[0010] As an implementation manner, the 2D camera group and the flash light group are in a symmetrical relationship with respect to the calibration device.

[0011] As an implementation manner, the 2D camera group and the flash light group have the same vertical distance relative to the normal of the calibration device.

[0012] The primary improvement of the present invention is that the detection device provided by the present invention can calibrate a 3D camera and a 2D camera at the same time, thereby obtaining more comprehensive detection data, simplifying the difficulty of unifying the coordinate systems of the 2D camera and the 3D camera, so that after the coordinate system is unified, the three-dimensional data trend and the two-dimensional data trend can be aligned, making full use of the stability of the three-dimensional data and the high-precision characteristics of the two-dimensional data, thereby obtaining high-precision and high-stability detection data. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0014] Figure 1 This is a front view of a pantograph detection device provided by one embodiment of the utility model;

[0015] Figure 2 It is a top view of a pantograph detection device provided by one embodiment of the utility model;

[0016] Figure 3 It is a structural schematic diagram of a calibration device provided in one embodiment of the utility model.

[0017] Description of reference numerals:

[0018] 1- calibration board, 2- 2D camera set, 3- 3D camera, 4- flash light set, 5- pantograph. DETAILED DESCRIPTION

[0019] In order to enable those skilled in the art to better understand the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0020] An embodiment of the utility model provides a pantograph detection device, which can perform joint calibration of three-dimensional / two-dimensional pantograph detection, and its front view is as follows Figure 1 As shown, its top view is as Figure 2 shown.

[0021] Specifically, the pantograph detection device includes: a calibration device and a camera unit, the calibration device is composed of three completely identical calibration plates, the calibration plates on both sides of the calibration device are arranged perpendicular to the middle calibration plate, and the calibration plates on both sides are non-contact and opposite to each other in the same direction; the camera unit includes a 2D camera group 2 and a 3D camera 3, the 3D camera is arranged directly above the middle calibration plate of the calibration device, and is used for three-dimensional image acquisition, and the 2D camera groups are respectively arranged on both sides of the calibration device, and are in the same direction as the calibration plates on both sides of the calibration device, and are used for two-dimensional image acquisition.

[0022] Furthermore, the calibration plate in this embodiment includes but is not limited to a square checkerboard. It can be understood that any shape of calibration plate that can be used for calibration is included in the protection scope of this application.

[0023] Furthermore, the 2D camera group includes at least four 2D cameras, and the number of 2D cameras on both sides is the same. The 2D camera is designed to perform two-dimensional image acquisition, and the calibration device of the present application is composed of three identical calibration plates. In order to acquire more comprehensive two-dimensional image information, the 2D camera needs to be able to acquire images in all directions without blind spots. At the same time, in order to achieve this technical effect at the lowest cost, that is, with the least number of cameras, the present application adopts a symmetrical arrangement method, by setting at least 4 2D cameras on the same horizontal line to generate intervals, thereby increasing the shooting angle, so as to achieve more comprehensive image data on the same horizontal line with the least possible number of cameras.

[0024] Furthermore, the detection device also includes a flashlight group, the flashlight group includes at least four flashlights, the four flashlights are respectively arranged on the inner side of the relative position of the 2D camera, and the horizontal height is consistent with the horizontal height of the 2D camera. The flashlight is set to improve the shooting quality of the camera group. Therefore, when setting the flashlight group, the present application considers the number of 2D camera groups for setting, and the number is the same as the number of cameras in the 2D camera group, and the positions are adjacent, so that each 2D camera is affected by the flashlight to the same degree, so as to reduce the data processing process and links when using the captured image data for image analysis and processing, and improve the overall efficiency.

[0025] Furthermore, the 2D camera group is set at a level higher than the level of the upper surface of the calibration device, and is used for capturing two-dimensional images of the upper surface and side surfaces of the calibration device.

[0026] Furthermore, the 3D camera is set at a higher level than the 2D camera group, and is used for collecting three-dimensional images of the upper surface of the calibration device.

[0027] Furthermore, the 2D camera group and the flash light group are in a symmetrical relationship with respect to the calibration device.

[0028] Furthermore, the 2D camera group and the flash light group have the same vertical distance relative to the normal of the calibration device.

[0029] A pantograph detection device provided by an embodiment of the utility model, through the above-mentioned structural design, enables the detection device to simultaneously obtain three-dimensional data of a 3D camera and two-dimensional data of a 2D camera, and based on the calibration of the 3D camera and the calibration of the 2D camera, it can convert the three-dimensional coordinates and the two-dimensional coordinates into a unified coordinate system, laying a technical foundation for the subsequent three-dimensional / two-dimensional joint calibration.

[0030] Furthermore, when the device is used for pantograph detection, first, a 2D camera group and a 3D camera are used simultaneously to shoot the calibration device to obtain a two-dimensional image and a three-dimensional image; the upper surface and the measuring surface of the calibration device are photographed by a 2D camera to obtain a two-dimensional image, and the upper surface of the calibration device is photographed by a 3D camera to obtain a three-dimensional image; the corner point data of the calibration plate in the calibration device are extracted, and all 2D cameras and 3D cameras are calibrated, and the calibration parameters of each camera are calculated; the reference coordinate system is obtained, and the coordinate systems of the 2D camera and the 3D camera are converted to the reference coordinate system; based on the two-dimensional image and the three-dimensional image, pixel trend data are extracted respectively, and data conversion is performed to obtain physical trend data corresponding to the pixel trend data; the three-dimensional physical trend and the two-dimensional physical trend are compared position by position, and the position where the difference between the two-dimensional physical trend and the three-dimensional physical trend is greater than the threshold is represented by the three-dimensional physical trend, and the other parts are represented by the two-dimensional physical trend to obtain the overall trend of pantograph detection.

[0031] It can be understood that the 2D camera group and the 3D camera are fixedly arranged, and the pantograph is placed under the calibration device. When shooting, the 2D camera can capture the upper surface and side surfaces of the calibration device, and the 3D camera can capture the upper surface of the calibration device.

[0032] Furthermore, any 2D camera can be selected as a reference camera, and its coordinate system can be extracted as the reference coordinate system; the coordinate systems of the remaining 2D cameras and 3D cameras can be uniformly converted to the reference coordinate system using the binocular space calibration technology.

[0033] Furthermore, based on the two-dimensional image and the three-dimensional image, two-dimensional pixel trend data and three-dimensional pixel trend data are extracted respectively; data conversion is performed using the calibration parameters and the alignment matrix to convert the pixel data into physical data to obtain physical trend data.

[0034] In this embodiment, the threshold of the difference between the two-dimensional physical trend and the three-dimensional physical trend is set to 0.5 mm, that is, when comparing the three-dimensional physical trend and the two-dimensional physical trend position by position, if the difference between the two-dimensional physical trend and the three-dimensional physical trend at a certain position is greater than 0.5 mm, the three-dimensional trend is used to replace the two-dimensional trend, and the other parts continue to use the two-dimensional trend. The final overall trend is obtained by combining the two-dimensional trend and the three-dimensional trend. The three-dimensional data is used to correct the unstable two-dimensional data, so as to achieve the trend correction of the two-dimensional data, realize the complementary advantages of the two-dimensional data and the three-dimensional data, and finally obtain high-precision and high-stability data.

[0035] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or system. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or system including the element.

[0036] The above are only preferred embodiments of the present invention. It should be noted that the above preferred embodiments should not be regarded as limiting the present invention. The protection scope of the present invention should be based on the scope defined by the claims. For ordinary technicians in this technical field, several improvements and modifications can be made without departing from the spirit and scope of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A pantograph detection device, characterized in that: include: A calibration device and a camera unit, wherein the calibration device is composed of three identical calibration plates, the calibration plates on both sides of the calibration device are arranged perpendicularly to the middle calibration plate, and the calibration plates on both sides are non-contacting and opposite to each other in the same direction; the camera unit includes a 2D camera group and a 3D camera, the 3D camera is arranged directly above the middle calibration plate of the calibration device for three-dimensional image acquisition, and the 2D camera groups are respectively arranged on both sides of the calibration device, and are in the same direction as the calibration plates on both sides of the calibration device for two-dimensional image acquisition.

2. A pantograph detection device according to claim 1, characterized in that: The 2D camera group includes at least four 2D cameras, and the number of 2D cameras on both sides is the same.

3. A pantograph detection device according to claim 2, characterized in that: It also includes a flashlight group, which includes at least four flashlights. The four flashlights are respectively arranged on the inner side of the relative position of the 2D camera, and the horizontal height is consistent with the horizontal height of the 2D camera.

4. A pantograph detection device according to claim 1, characterized in that: The 2D camera group is arranged at a level higher than the level of the upper surface of the calibration device, and is used for collecting two-dimensional images of the upper surface and side surfaces of the calibration device.

5. A pantograph detection device according to claim 4, characterized in that: The 3D camera is set at a higher level than the 2D camera group, and is used for collecting three-dimensional images of the upper surface of the calibration device.

6. A pantograph detection device according to claim 3, characterized in that: The 2D camera group and the flash light group are in a symmetrical relationship with respect to the calibration device.

7. A pantograph detection device according to claim 6, characterized in that: The 2D camera group and the flash light group have the same vertical distance relative to the normal of the calibration device.

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