Cable joint engagement state detection method and device, electronic equipment and storage medium

Abstract

The application provides a cable joint meshing state detection method and device, electronic equipment and storage medium. The method comprises: calibrating a shooting unit to obtain shooting unit parameters of the shooting unit; performing position calibration according to the shooting unit parameters to obtain a first pose transformation relationship between the shooting unit and a moving contact of the cable joint; performing elliptical correction processing on an elliptical contour formed by perspective transformation of a circular contour at the bottom of a stationary contact of the cable joint according to the shooting unit parameters to obtain a second pose transformation relationship between the shooting unit and the stationary contact of the cable joint; and obtaining the meshing state of the cable joint according to the first pose transformation relationship and the second pose transformation relationship. The cable joint meshing state detection method provided in the application can further ensure the accuracy of position measurement and direction measurement of the meshing position of the cable joint.

Description

Technical Field

[0001] This application relates to the field of equipment testing technology, specifically to a method, device, electronic device, and storage medium for detecting the engagement state of cable connectors. Background Technology

[0002] The normal operation of smart city communication equipment is essential for social life, and the stability of the moving and stationary contacts in communication cable connections is a prerequisite for the reliable operation of the communication system. Their engagement depth and alignment directly affect the contact resistance. Excessive contact depth or excessive alignment tilt can lead to unstable contact connections, affecting communication quality. Therefore, detecting the engagement status of communication connectors is of great significance. Early methods estimated the engagement depth by measuring scratches on the stationary contact. This method requires removing the stationary contact after full engagement for measurement. Since the stationary contact is energized and individual disassembly and inspection are cumbersome, real-time measurement is impossible, and it is difficult to apply in practical environments.

[0003] Currently, for the detection of contact engagement status in communication equipment, existing solutions mainly include measurement schemes based on wireless data transmission from sensors; displacement sensors offer high measurement accuracy, can adapt to harsh measurement environments, and achieve relatively reliable data transmission; this method offers high depth measurement accuracy and can adapt well to strong magnetic sealed environments, but it cannot measure alignment and requires high installation accuracy. Summary of the Invention

[0004] This application provides a method, apparatus, electronic device, and storage medium for detecting the engagement state of a cable connector, in order to solve the technical problem of inaccurate detection of the engagement state of existing cable connectors.

[0005] In a first aspect, embodiments of this application provide a method for detecting the engagement state of a cable connector, including:

[0006] The shooting unit is calibrated to obtain the shooting unit parameters;

[0007] The position is calibrated based on the shooting unit parameters to obtain the first pose transformation relationship between the shooting unit and the moving contact of the cable connector;

[0008] Based on the shooting unit parameters, the elliptical contour formed by perspective transformation of the circular outline at the bottom of the cable connector stationary contact is elliptical corrected to obtain the second pose transformation relationship between the shooting unit and the cable connector stationary contact.

[0009] The engagement state of the cable connector is obtained based on the first pose transformation relationship and the second pose transformation relationship.

[0010] In one embodiment, the step of calibrating the imaging unit to obtain the imaging unit parameters includes:

[0011] Based on a pre-set chessboard grid, acquire the image of the shooting unit corresponding to the chessboard grid;

[0012] Obtain the actual coordinates of the chessboard grid and the corner coordinates of the image captured by the camera unit;

[0013] Based on the real-world coordinates of the chessboard and the coordinates of the corner points, the third pose transformation relationship is obtained;

[0014] Based on the third pose transformation relationship, the shooting unit parameters of the shooting unit are obtained.

[0015] In one embodiment, obtaining the shooting unit parameters of the shooting unit based on the third pose transformation relationship includes:

[0016] Multiple sets of initial shooting unit parameters are obtained based on the third pose transformation relationship;

[0017] The shooting unit parameters are obtained from multiple sets of initial shooting unit parameters using the maximum likelihood estimation method.

[0018] In one embodiment, the step of performing position calibration based on the imaging unit parameters to obtain the first pose transformation relationship between the imaging unit and the moving contact includes:

[0019] The position is calibrated according to the shooting unit parameters to obtain the fourth pose transformation relationship between the shooting unit and the calibration plate set on the stationary contact.

[0020] Based on the fourth pose transformation relationship and the geometric parameters of the cable connector calibration component, the first pose transformation relationship is obtained.

[0021] In one embodiment, the step of performing elliptical correction processing on the elliptical contour formed by perspective transformation of the circular contour at the bottom of the stationary contact of the cable connector according to the shooting unit parameters, to obtain the second pose transformation relationship between the shooting unit and the stationary contact of the cable connector, includes:

[0022] Obtain the initial elliptical contour formed by perspective transformation of the circular contour at the bottom of the stationary contact of the cable connector;

[0023] The inverse perspective transformation matrix is ​​obtained based on the shooting unit parameters;

[0024] Based on the inverse perspective transformation matrix, the initial elliptical contour is subjected to inverse perspective transformation to obtain the corrected elliptical contour;

[0025] The second pose transformation relationship is obtained based on the circular contour and the modified elliptical contour.

[0026] In one embodiment, it also includes:

[0027] The first pose transformation relationship data is digitized to obtain the first pose transformation relationship data, and the first pose transformation relationship data is displayed on the preset position calibration interface;

[0028] Based on the first pose transformation relationship and the second pose transformation relationship, the engagement state of the cable connector is displayed on a pre-set visual measurement interface.

[0029] Secondly, embodiments of this application provide a cable connector engagement state detection system, including: an imaging unit, an imaging unit parameter acquisition unit, a first relationship acquisition unit, a second relationship acquisition unit, and an engagement state detection unit;

[0030] The camera unit is located at the cable connector engagement position;

[0031] A shooting unit parameter acquisition unit, connected to the shooting unit, is used to calibrate the shooting unit and obtain the shooting unit parameters of the shooting unit;

[0032] The first relationship acquisition unit is connected to the shooting unit parameter acquisition unit and is used to perform position calibration according to the shooting unit parameters to obtain the first pose transformation relationship between the shooting unit and the moving contact of the cable connector.

[0033] The second relationship acquisition unit is connected to the shooting unit parameter acquisition unit and is used to perform ellipse correction processing on the ellipse contour formed by perspective transformation of the circular contour at the bottom of the cable connector stationary contact according to the shooting unit parameters, so as to obtain the second pose transformation relationship between the shooting unit and the cable connector stationary contact.

[0034] The engagement state detection unit is connected to the first relationship acquisition unit and the second relationship acquisition unit, and is used to obtain the engagement state of the cable connector based on the first pose transformation relationship and the second pose transformation relationship.

[0035] Thirdly, embodiments of this application also provide a cable connector engagement state detection device, comprising:

[0036] The shooting unit parameter acquisition module is used to calibrate the shooting unit and obtain the shooting unit parameters of the shooting unit.

[0037] The first relationship acquisition module is used to perform position calibration based on the shooting unit parameters to obtain the first pose transformation relationship between the shooting unit and the moving contact of the cable connector;

[0038] The second relationship acquisition module is used to perform elliptical correction processing on the elliptical contour formed by perspective transformation of the circular contour at the bottom of the static contact of the cable connector according to the shooting unit parameters, so as to obtain the second pose transformation relationship between the shooting unit and the static contact of the cable connector.

[0039] The engagement state detection module is used to obtain the engagement state of the cable connector based on the first pose transformation relationship and the second pose transformation relationship.

[0040] Fourthly, embodiments of this application provide an electronic device, including a processor and a memory storing a computer program, wherein the processor executes the program to implement the cable connector engagement state detection method described in the first aspect.

[0041] Fifthly, embodiments of this application provide a computer program product, including a computer program that, when executed by a processor, implements the cable connector engagement state detection method described in the first aspect.

[0042] The cable connector engagement state detection method, apparatus, electronic device, and storage medium provided in this application can detect the engagement state between the moving and stationary contacts of the cable connector by using the first pose transformation relationship between the imaging unit and the moving contact of the cable connector, and the second pose relationship between the imaging unit and the stationary contact of the cable connector, when detecting the engagement position of the cable connector. By combining the first pose transformation relationship determined by the imaging unit calibration and position calibration with the second pose relationship obtained by the ellipse correction algorithm, measurement errors between the moving and stationary contacts of the cable connector can be prevented, further ensuring the accuracy of the position and direction measurement of the cable connector engagement position. Attached Figure Description

[0043] To more clearly illustrate the technical solutions in this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0044] Figure 1 This is a flowchart illustrating the cable connector engagement state detection method provided in the embodiments of this application;

[0045] Figure 2 This is a schematic diagram of the position calibration of the cable connector engagement state detection method provided in the embodiments of this application;

[0046] Figure 3 This is a schematic diagram of the camera unit calibration process for the cable connector engagement state detection method provided in this application embodiment;

[0047] Figure 4 This is a schematic diagram of the engagement of the moving and stationary contacts in the cable connector engagement state detection method provided in this application embodiment;

[0048] Figure 5 This is a schematic diagram comparing perspective transformation before and after, provided in an embodiment of this application;

[0049] Figure 6 This is a schematic diagram of the engagement status display interface provided in the embodiments of this application;

[0050] Figure 7 This is a schematic diagram of data interaction of the engagement status display interface provided in the embodiments of this application;

[0051] Figure 8 This is a schematic diagram of the position calibration interface provided in an embodiment of this application;

[0052] Figure 9 This is a schematic diagram of the parameter setting interface provided in an embodiment of this application;

[0053] Figure 10 This is a schematic diagram of the cable connector engagement status detection system provided in the embodiments of this application;

[0054] Figure 11 This is a schematic diagram of the cable connector engagement state detection device provided in the embodiments of this application;

[0055] Figure 12 This is a schematic diagram of the structure of the electronic device provided in the embodiments of this application. Detailed Implementation

[0056] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0057] The terms "first," "second," etc., used in this application's specification are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein. Furthermore, the term "and / or" in the specification indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0058] Figure 1This is a schematic flowchart of the cable connector engagement state detection method provided in an embodiment of this application. (Refer to...) Figure 1 This application provides a method for detecting the engagement state of a cable connector, which may include:

[0059] Step 101: Perform shooting unit calibration on the shooting unit to obtain the shooting unit parameters of the shooting unit.

[0060] This can be understood as follows: in this application, the imaging unit is first calibrated to obtain the parameters of the imaging unit, such as external parameters, internal parameters, and distortion parameters.

[0061] For example, a chessboard image is obtained by taking a picture of the chessboard using the camera unit, thus achieving camera unit calibration; the camera unit parameters are obtained through camera unit calibration, including camera unit intrinsic parameters, distortion parameters, and camera unit extrinsic parameters.

[0062] The shooting unit can be a digital camera or a video camera.

[0063] The purpose of camera unit calibration, or camera calibration, is to establish the pose transformation between the camera coordinate system and the image physical coordinate system. Through this pose transformation relationship, camera parameters such as extrinsic parameters, intrinsic parameters, and distortion parameters are obtained. The coordinate systems involved in calibration mainly include the camera coordinate system, image pixel coordinate system, image physical coordinate system, and world coordinate system. The relationship between the camera coordinate system and the world coordinate system is shown in the following equation:

[0064]

[0065] In the formula, X w ,Y w Z w Let be the world coordinates, u and v be the pixel coordinates, f be the focal length, u0 and v0 be the pixel coordinates of the camera's optical center, and dx and dy be the pixel sizes in the x and y directions, respectively. M1 and M2 are the intrinsic and extrinsic parameter matrices of the imaging unit.

[0066] For example, camera calibration can be performed using a 15.6-inch computer with a screen resolution of 1920x1080, a pixel density of 141.21 dots per inch (0.1799mm), and an 8x10 electronic chessboard (7mm x 7mm). The corresponding camera image is then obtained using the Hypertext Transfer Protocol (HTTP). Camera calibration is then performed based on the obtained image to obtain the camera parameters of the imaging unit. These camera parameters include intrinsic camera parameters, distortion parameters, and extrinsic camera parameters.

[0067] Step 102: Position calibration is performed based on the shooting unit parameters to obtain the first pose transformation relationship between the shooting unit and the moving contact of the cable connector.

[0068] This can be understood as, Figure 2 This is a schematic diagram of the position calibration of the cable connector engagement state detection method provided in the embodiments of this application. (Refer to...) Figure 2 During the observation of the engagement state of cable connectors, a coordinate system is constructed according to the target to be observed, such as the moving contact of the cable connector and the moving contact of the cable connector.

[0069] After obtaining the intrinsic parameters, distortion parameters, and extrinsic parameters of the imaging unit, the first pose transformation relationship between the imaging unit and the moving contact of the cable connector can be obtained based on these parameters.

[0070] Step 103: Based on the shooting unit parameters, perform elliptical correction processing on the elliptical contour formed by perspective transformation of the circular contour at the bottom of the cable connector stationary contact to obtain the second pose transformation relationship between the shooting unit and the cable connector stationary contact.

[0071] This can be understood as follows: during the installation of the imaging unit, the mounting plane of the imaging unit and the bottom plane of the stationary contact of the cable connector may not be parallel. Therefore, the target contour (circular contour) to be identified, which is pre-set on the stationary contact of the cable connector, will be deformed into an elliptical contour after perspective transformation. By performing elliptical correction processing on the elliptical contour using the extrinsic parameters of the imaging unit, the corrected elliptical contour can be obtained. Then, based on the corrected elliptical contour and the target contour to be identified, the second pose transformation relationship between the imaging unit and the stationary contact of the cable connector can be obtained.

[0072] Step 104: Based on the first pose transformation relationship and the second pose transformation relationship, obtain the engagement state of the cable connector.

[0073] This can be understood as follows: after obtaining the first pose transformation relationship between the shooting unit and the moving contact of the cable connector, and the second pose transformation relationship between the shooting unit and the stationary contact of the cable connector, the pose transformation relationship between the moving contact and the stationary contact of the cable connector can be calculated, and the engagement state of the cable connector can be obtained based on this pose transformation relationship.

[0074] This embodiment of the application, when detecting the engagement position of a cable connector, can detect the engagement state between the moving and stationary contacts of the cable connector based on the first pose transformation relationship between the imaging unit and the moving contact of the cable connector, and the second pose relationship between the imaging unit and the stationary contact of the cable connector. By combining the first pose transformation relationship determined by the imaging unit calibration and position calibration with the second pose relationship obtained by the ellipse correction algorithm, measurement errors between the moving and stationary contacts of the cable connector can be prevented, further ensuring the accuracy of the position and direction measurement of the cable connector engagement position.

[0075] Further, the step of calibrating the shooting unit to obtain the shooting unit parameters includes:

[0076] Based on a pre-set chessboard grid, acquire the image of the shooting unit corresponding to the chessboard grid;

[0077] Obtain the actual coordinates of the chessboard grid and the corner coordinates of the image captured by the camera unit;

[0078] Based on the real-world coordinates of the chessboard and the coordinates of the corner points, the third pose transformation relationship is obtained;

[0079] Based on the third pose transformation relationship, the shooting unit parameters of the shooting unit are obtained.

[0080] This can be understood as follows: in this application, an electronic chessboard grid can be created first, and then a certain number of images of the shooting unit corresponding to the chessboard grid can be obtained based on the pre-created chessboard grid.

[0081] Then, Harris corner detection is performed and sub-pixel precision is applied. That is, by using the corner coordinates of the captured unit image and the checkerboard corner coordinates in the actual world coordinate system, the pose transformation relationship between the world coordinate system and the image coordinate system corresponding to each captured unit image is obtained, which is the third pose transformation relationship.

[0082] After obtaining multiple sets of third pose transformation relationships, the shooting unit parameters of the shooting unit are obtained based on the multiple sets of third pose transformation relationships.

[0083] This application enables accurate calibration of shooting units by pre-creating an electronic chessboard grid and obtaining the pose transformation relationship between the world coordinate system and the image coordinate system corresponding to each shooting unit image based on the electronic chessboard grid.

[0084] Further, obtaining the shooting unit parameters of the shooting unit based on the third pose transformation relationship includes:

[0085] Multiple sets of initial shooting unit parameters are obtained based on the third pose transformation relationship;

[0086] The shooting unit parameters are obtained from multiple sets of initial shooting unit parameters using the maximum likelihood estimation method.

[0087] This can be understood as, Figure 3 This is a schematic diagram of the camera unit calibration process for the cable connector engagement state detection method provided in this application embodiment. (Refer to...) Figure 3After creating an electronic chessboard and acquiring a certain number of image units corresponding to the pre-created chessboard, Harris corner detection and sub-pixel precision are performed. This involves using the corner coordinates of the image units and the corner coordinates of the chessboard in the actual world coordinate system to obtain the pose transformation relationship between the world coordinate system and the image coordinate system for each image unit.

[0088] Then, based on the third pose transformation relationship, multiple sets of initial shooting unit parameters are obtained, and the shooting unit parameters are obtained from the multiple sets of initial shooting unit parameters using the maximum likelihood estimation method.

[0089] This application obtains multiple sets of initial shooting unit parameters through a third pose transformation relationship, and obtains the shooting unit parameters from the multiple sets of initial shooting unit parameters according to the maximum likelihood estimation method, so as to accurately perform shooting unit calibration.

[0090] Further, the step of performing position calibration based on the parameters of the imaging unit to obtain the first pose transformation relationship between the imaging unit and the moving contact includes:

[0091] The position is calibrated according to the shooting unit parameters to obtain the fourth pose transformation relationship between the shooting unit and the calibration plate set on the stationary contact.

[0092] Based on the fourth pose transformation relationship and the geometric parameters of the cable connector calibration component, the first pose transformation relationship is obtained.

[0093] It can be understood that, in this application, the cable connector includes a moving contact of the cable connector, a stationary contact of the cable connector, a shooting unit, a calibration plate, and a calibration cylinder.

[0094] First, the pose transformation relationship between the pixel coordinate system and the world coordinate system is obtained based on the shooting unit parameters. Then, the positions of the shooting unit and the calibration plate on the stationary contact of the cable connector are calibrated according to this pose transformation relationship, thus obtaining the fourth pose transformation relationship T between the shooting unit and the calibration plate set on the stationary contact. 相-标定板 .

[0095] After obtaining the fourth pose transformation relationship T between the imaging unit and the calibration plate 相-标定板 Then, combined with the dimension D of the calibration cylinder 标定筒 The fifth pose transformation relationship T between the imaging unit and the calibration tube is obtained. 相-标定筒 Then, based on the fifth pose transformation relationship T 相-标定筒 The first pose transformation relationship T between the imaging unit and the moving contact of the cable connector is obtained by combining the dimensions of the moving contact of the cable connector. 相-标定筒 .

[0096] Specifically, the fourth pose transformation relationship T between the shooting unit and the calibration plate can be set.相-标定板 For X 相-标板 Y 相-标板 Z 相-标板 The fifth pose transformation relationship between the imaging unit and the calibration tube (T) 相-标定筒 The calculation formula is X 相-标定筒 =X 相-标板 Y 相-标定筒 =Y 相-标板 Z 相-标定筒 =Z 相-标板 The first pose conversion relationship between the shooting unit and the moving contact of the cable connector (T) 相-标定筒 The calculation formula is X 相-动触头 =X 相-标筒 Y 相-动触头 =Y 相-标筒 Z 相-动触头 =Z 相-标定筒 -(D 标定筒 -D 静触头 ).

[0097] This application can accurately obtain the first pose transformation relationship by using the fourth pose transformation relationship between the shooting unit and the calibration plate set on the stationary contact and the geometric structural parameters of the cable connector calibration component.

[0098] Further, the step of performing elliptical correction processing on the elliptical contour formed by perspective transformation of the circular contour at the bottom of the stationary contact of the cable connector based on the shooting unit parameters, to obtain the second pose transformation relationship between the shooting unit and the stationary contact of the cable connector, includes:

[0099] Obtain the initial elliptical contour formed by perspective transformation of the circular contour at the bottom of the stationary contact of the cable connector;

[0100] The inverse perspective transformation matrix is ​​obtained based on the shooting unit parameters;

[0101] Based on the inverse perspective transformation matrix, the initial elliptical contour is subjected to inverse perspective transformation to obtain the corrected elliptical contour;

[0102] The second pose transformation relationship is obtained based on the circular contour and the modified elliptical contour.

[0103] This can be understood as, Figure 4 This is a schematic diagram of the engagement of the moving and stationary contacts in the cable connector engagement state detection method provided in this application embodiment. (Refer to...) Figure 4Because the mounting plane of the imaging unit may not be parallel to the plane of the stationary contact of the cable connector, the shape of the target outline (circular outline) to be identified at the bottom of the stationary contact of the cable connector after perspective transformation deviates from the original circular outline, forming an elliptical outline, i.e., the initial elliptical outline. The initial elliptical outline differs significantly from the original circular outline. Directly using the uncorrected elliptical outline for pose estimation will cause a large error. However, the corrected elliptical outline after inverse perspective transformation is much closer to the circular outline. The inverse perspective transformation matrix can be obtained by modifying the matrix R of the imaging unit's extrinsic parameters in the imaging unit parameters. 标 The inverse is obtained by performing the inverse operation.

[0104] Inverse perspective transformation is the reverse process of perspective transformation. The general perspective transformation formula is shown below:

[0105]

[0106] x = a 11 u+a 12 v+a 13 #

[0107] y = a 21 u+a 22 v+a 23 #

[0108] z = a 31 u+a 32 v+a 33 #

[0109]

[0110]

[0111] In the formula, u,v are the pixel coordinates of the original image, x,y,z are the three-dimensional coordinates after perspective transformation, and x′,y′ are the two-dimensional coordinates after perspective transformation. This is the perspective transformation matrix. Represents the linear transformation matrix of the image, [a 31 a 32 ] is the image translation matrix, [a 13 a 23 ] T Represents the perspective transformation relationship of an image.

[0112] Since the perspective transformation matrix has 8 unknowns, it can be determined using 4 sets of corresponding points on a 2D plane. To test the effect of the perspective transformation matrix on a contour, a perspective transformation experiment was designed. The initial contour was designed with a radius of 50 pixels and a center at [150, 150]. The coordinates of the four sets of points before and after the perspective transformation were [0, 0], [300, 0], [0, 300], [300, 300] and [56, 70], [290, 52], [28, 280], [289, 290], respectively. The perspective transformation matrix M was then calculated. 透视 As shown below:

[0113]

[0114] Figure 5 This is a schematic diagram comparing perspective transformation before and after, provided in an embodiment of this application. (Refer to...) Figure 5 After perspective transformation, we obtain the images before and after the perspective transformation.

[0115] The original image coordinates are then obtained using the following formula, which is shown below:

[0116]

[0117] In the formula, u,v are the pixel coordinates of the original image, and x′,y′ are the two-dimensional coordinates after perspective transformation.

[0118] The inverse of the perspective transformation matrix is ​​shown below:

[0119]

[0120] The elliptical features before and after the inverse perspective transformation are shown in Table 1.

[0121] Table 1. Elliptical features before and after inverse perspective transformation

[0122]

[0123] As can be seen from the table above, the initial elliptical contour and the original circular contour are quite different. If the uncorrected elliptical contour is used directly for pose estimation, it will cause a large error. However, the corrected elliptical contour after inverse perspective transformation is closer to the circular contour.

[0124] The inverse perspective transformation matrix can be obtained by combining the pose transformation matrix obtained from the calibration. For example, the translation matrix R obtained after position calibration in this application. 标 and T 标 As shown in the following formula:

[0125]

[0126]

[0127] First, four sets of points in the world coordinate system are selected, as shown in Table 2:

[0128] Table 2. Point Coordinates in World Coordinate System

[0129]

[0130]

[0131] Before and after ellipse correction, there are two sets of pose transformation matrices, as shown in the following equation M. 矫正后 and M 矫正前 As shown, the difference between the two is that the pose transformation matrix and rotation matrix in the corrected state are identity matrices, which means that no rotation occurs and the state is parallel.

[0132]

[0133] Corrected pose transformation matrix M 矫正前 As shown below:

[0134]

[0135] Then multiply the coordinates in Table 2 by M on the left. 矫正前 and M 矫正后 The pixel coordinates before and after correction were obtained, and the results are shown in Tables 3 and 4 below.

[0136] Table 3 Actual pixel coordinates

[0137] Point number 1 2 3 4 x-coordinate 1062.23459000 872.71392248 683.19325699 872.71392248 y coordinate 556.35067800 745.99401901 556.35067780 366.70733658

[0138] Table 4 Corrected pixel coordinates

[0139] Point number 1 2 3 4 x-coordinate 1062.31501000 872.69571867 683.25567097 872.73215402 y coordinate 556.33244400 745.88676864 556.36889835 366.52589178

[0140] The inverse perspective transformation matrix M is obtained by using the pixel coordinates before and after correction in four sets. 逆 As shown in the following formula:

[0141]

[0142] The single-pixel elliptical contour is corrected by inverse perspective transformation, and the ellipse's features are fitted to obtain the corrected elliptical contour. After obtaining the circular contour and the corrected elliptical contour, the second pose transformation relationship T between the imaging unit and the stationary contact of the cable connector can be determined based on the circular contour and the corrected elliptical contour. 相-静触头 .

[0143] The second pose transformation relationship T between the shooting unit and the stationary contact of the cable connector is obtained. 相-静触头 Then, based on the first pose transformation relationship T 相-标定筒和Second pose transformation relationship T 相-静触头 The engagement state between the stationary contact and the moving contact of the cable connector is obtained.

[0144] Specifically, the second pose transformation relationship T between the shooting unit and the stationary contact of the cable connector can be set. 相-静触头 For X 相-静触头 Y 相-静触头 Z 相-静触头 Then, based on the first pose transformation relationship T... 相-标定筒和 Second pose transformation relationship T 相-静触头 The pose transformation relationship T between the moving contact and the stationary contact of the cable connector is obtained. 动-静 Pose transformation relationship T 动-静 The calculation formula is X 动-静 =X 相-动触头 -X 相-静触头 Y 动-静 =Y 相-动触头 -Y 相-静触头 Z 动-静 =D 动静触头完全啮合深度 -(Z 相-静触头 -Z 相-动触头 )-D 初始啮合深度 Then, based on the positional change relationship T between the moving contact and the stationary contact of the cable connector... 动-静 The positional deviation of the stationary and moving contacts in three directions can determine the meshing state between the stationary and moving contacts of the cable connector.

[0145] Among them, because the moving and stationary contacts have an initial engagement depth, Z 动-静 D needs to be subtracted during the calculation. 初始啮合深度 .

[0146] This application uses an ellipse correction algorithm to transform the circular outline at the bottom of the stationary contact of the cable connector into an elliptical outline through perspective transformation, thereby obtaining a more accurate second pose transformation relationship between the shooting unit and the stationary contact of the cable connector.

[0147] Furthermore, it also includes:

[0148] The first pose transformation relationship data is digitized to obtain the first pose transformation relationship data, and the first pose transformation relationship data is displayed on the preset position calibration interface;

[0149] Based on the first pose transformation relationship and the second pose transformation relationship, the engagement state of the cable connector is displayed on a pre-set visual measurement interface.

[0150] This application can be understood to include a visual measurement interface, a position calibration interface, and a parameter setting interface. The visual measurement interface displays meshing state data and provides a tool menu for device control. The position calibration interface allows for the display of corner point recognition results and calibration results, and provides a tool menu for data saving and updating. The parameter setting interface is mainly used to set some basic visual measurement parameters to improve the system's adaptability.

[0151] Figure 6 This is a schematic diagram of the engagement status display interface provided in an embodiment of this application, referring to... Figure 6 The visual measurement interface is mainly used for displaying the engagement status, showing the image data transmitted by six sets of measuring devices, the engagement status parameters calculated by the host computer, and the WIFI status of the devices. At the same time, a lower-level control button menu is set up to realize the control of the lower-level device.

[0152] Figure 7 This is a schematic diagram of the data interaction of the engagement status display interface provided in the embodiments of this application, with reference to... Figure 7 The main body of the visual measurement display interface is implemented based on the model-view-delegate (MVD) design pattern, which decouples the underlying data and the user interface (UI), achieving data and display isolation, ensuring smooth UI display and data security, and providing good scalability. The lower-level control menu includes a contact type input box to transmit user input to the model and view. The engagement data display sends signals of changes in engagement state to the delegate to update the view.

[0153] Figure 8 This is a schematic diagram of the location calibration interface provided in the embodiments of this application, with reference to... Figure 8 The position calibration interface mainly displays the calibration image results and reprojection error. It can save and update the results, and indicate whether the calibration was successful and whether recalibration is required.

[0154] Figure 9 This is a schematic diagram of the parameter setting interface provided in the embodiments of this application, referred to as follows. Figure 9 It is mainly used to set some basic parameters, such as the basic dimensions of the contact, including the inner diameter, depth, and initial depth. By setting these parameters, it is possible to measure different types of contacts. The medium and depth alarm thresholds are used to adjust the alarm information triggering. The image processing thresholds include the maximum and minimum area of ​​the identified contour to avoid misidentification and achieve accurate measurement under different measurement environments. At the same time, the display interface can be adjusted by adjusting the shooting unit number toolbar when the equipment is installed incorrectly.

[0155] This application enables real-time monitoring and control of the testing process by setting up interfaces such as position calibration interface, which is beneficial for detecting the engagement state of cable joints.

[0156] Figure 10 This is a schematic diagram of the detection system provided in the embodiments of this application, with reference to... Figure 10 This application provides a detection system, including: an imaging unit 1001, an imaging unit parameter acquisition unit 1002, a first relationship acquisition unit 1003, a second relationship acquisition unit 1004, and a meshing state detection unit 1005, wherein:

[0157] The imaging unit 1001 is located at the cable connector engagement position;

[0158] The shooting unit parameter acquisition unit 1002 is connected to the shooting unit and is used to perform shooting unit calibration on the shooting unit to obtain the shooting unit parameters of the shooting unit.

[0159] The first relationship acquisition unit 1003 is connected to the shooting unit parameter acquisition unit and is used to perform position calibration according to the shooting unit parameters to obtain the first pose transformation relationship between the shooting unit and the moving contact of the cable connector.

[0160] The second relationship acquisition unit 1004 is connected to the shooting unit parameter acquisition unit and is used to perform ellipse correction processing on the ellipse contour formed by perspective transformation of the circular contour at the bottom of the cable connector stationary contact according to the shooting unit parameters, so as to obtain the second pose transformation relationship between the shooting unit and the cable connector stationary contact.

[0161] The engagement state detection unit 1005 is connected to the first relationship acquisition unit and the second relationship acquisition unit, and is used to obtain the engagement state of the cable connector based on the first pose transformation relationship and the second pose transformation relationship.

[0162] This application, when detecting the engagement position of a cable connector, can detect the engagement state between the moving and stationary contacts of the cable connector based on the first pose transformation relationship between the imaging unit and the moving contact of the cable connector, and the second pose relationship between the imaging unit and the stationary contact of the cable connector. By combining the first pose transformation relationship determined by the imaging unit calibration and position calibration with the second pose relationship obtained through the ellipse correction algorithm, measurement errors between the moving and stationary contacts of the cable connector can be prevented, further ensuring the accuracy of the position and direction measurement of the cable connector engagement position.

[0163] The cable connector engagement state detection device provided in the embodiments of this application is described below. The cable connector engagement state detection device described below and the cable connector engagement state detection method described above can be referred to in correspondence.

[0164] Figure 11 This is a schematic diagram of the cable connector engagement status detection device provided in the embodiments of this application, with reference to... Figure 11 This application provides a cable connector engagement state detection device, including a shooting unit parameter acquisition module 1101, a first relationship acquisition module 1102, a second relationship acquisition module 1103, and an engagement state detection module 1104, wherein: the shooting unit parameter acquisition module 1101 is used to calibrate the shooting unit to obtain the shooting unit parameters; the first relationship acquisition module 1102 is used to perform position calibration based on the shooting unit parameters to obtain the first pose transformation relationship between the shooting unit and the moving contact of the cable connector; the second relationship acquisition module 1103 is used to perform ellipse correction processing on the elliptical contour formed by perspective transformation of the circular contour at the bottom of the stationary contact of the cable connector based on the shooting unit parameters to obtain the second pose transformation relationship between the shooting unit and the stationary contact of the cable connector; the engagement state detection module 1104 is used to obtain the engagement state of the cable connector based on the first pose transformation relationship and the second pose transformation relationship.

[0165] The cable connector engagement state detection device provided in this application uses a checkerboard image acquired by the imaging unit to calibrate the imaging unit and obtain the imaging unit parameters. Based on the imaging unit parameters, it obtains the first pose transformation relationship between the imaging unit and the moving contact of the cable connector, and the second pose transformation relationship between the imaging unit and the stationary contact of the cable connector. Based on the obtained first pose transformation relationship and second pose transformation relationship, it accurately detects the engagement state of the cable connector.

[0166] Furthermore, the shooting unit parameter acquisition module is also used for:

[0167] Based on a pre-set chessboard grid, acquire the image of the shooting unit corresponding to the chessboard grid;

[0168] Obtain the actual coordinates of the chessboard grid and the corner coordinates of the image captured by the camera unit;

[0169] Based on the real-world coordinates of the chessboard and the coordinates of the corner points, the third pose transformation relationship is obtained;

[0170] Based on the third pose transformation relationship, the shooting unit parameters of the shooting unit are obtained.

[0171] Furthermore, the shooting unit parameter acquisition module is also used for:

[0172] Multiple sets of initial shooting unit parameters are obtained based on the third pose transformation relationship;

[0173] The shooting unit parameters are obtained from multiple sets of initial shooting unit parameters using the maximum likelihood estimation method.

[0174] Furthermore, the first relationship acquisition module is also used for:

[0175] The position is calibrated according to the shooting unit parameters to obtain the fourth pose transformation relationship between the shooting unit and the calibration plate set on the stationary contact.

[0176] Based on the fourth pose transformation relationship and the geometric parameters of the cable connector calibration component, the first pose transformation relationship is obtained.

[0177] Furthermore, the second relationship acquisition module is also used for:

[0178] Obtain the initial elliptical contour formed by perspective transformation of the circular contour at the bottom of the stationary contact of the cable connector;

[0179] The inverse perspective transformation matrix is ​​obtained based on the shooting unit parameters;

[0180] Based on the inverse perspective transformation matrix, the initial elliptical contour is subjected to inverse perspective transformation to obtain the corrected elliptical contour;

[0181] The second pose transformation relationship is obtained based on the circular contour and the modified elliptical contour.

[0182] Furthermore, it also includes a display module for:

[0183] The first pose transformation relationship data is digitized to obtain the first pose transformation relationship data, and the first pose transformation relationship data is displayed on the preset position calibration interface;

[0184] Based on the first pose transformation relationship and the second pose transformation relationship, the engagement state of the cable connector is displayed on a pre-set visual measurement interface.

[0185] Figure 12 This is a schematic diagram of the structure of the electronic device provided in the embodiments of this application, with reference to... Figure 12The electronic device may include a processor 1201, a communication interface 1202, a memory 1203, and a communication bus 1204, wherein the processor 1201, the communication interface 1202, and the memory 1203 communicate with each other via the communication bus 1204. The processor 1201 can call the computer program in the memory 1203 to execute the cable connector engagement state detection method provided in the above-described method embodiments, for example including: calibrating the imaging unit to obtain the imaging unit parameters; performing position calibration based on the imaging unit parameters to obtain the first pose transformation relationship between the imaging unit and the moving contact of the cable connector; performing ellipse correction processing on the elliptical contour formed by perspective transformation of the circular contour at the bottom of the stationary contact of the cable connector based on the imaging unit parameters to obtain the second pose transformation relationship between the imaging unit and the stationary contact of the cable connector; and obtaining the engagement state of the cable connector based on the first pose transformation relationship and the second pose transformation relationship.

[0186] Furthermore, the logical instructions in the aforementioned memory 1203 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0187] On the other hand, this application also provides a computer program product, which includes a computer program that can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the cable connector engagement state detection method provided in the above-described method embodiments, for example including: calibrating the imaging unit to obtain the imaging unit parameters; performing position calibration based on the imaging unit parameters to obtain a first pose transformation relationship between the imaging unit and the moving contact of the cable connector; performing ellipse correction processing on the elliptical contour formed by perspective transformation of the circular contour at the bottom of the stationary contact of the cable connector based on the imaging unit parameters to obtain a second pose transformation relationship between the imaging unit and the stationary contact of the cable connector; and obtaining the engagement state of the cable connector based on the first pose transformation relationship and the second pose transformation relationship.

[0188] On the other hand, embodiments of this application also provide a processor-readable storage medium storing a computer program. The computer program is used to cause a processor to execute the cable connector engagement state detection method provided in the above-described method embodiments. For example, it includes: calibrating a shooting unit to obtain shooting unit parameters; performing position calibration based on the shooting unit parameters to obtain a first pose transformation relationship between the shooting unit and the moving contact of the cable connector; performing ellipse correction processing on the elliptical contour formed by perspective transformation of the circular contour at the bottom of the stationary contact of the cable connector based on the shooting unit parameters to obtain a second pose transformation relationship between the shooting unit and the stationary contact of the cable connector; and obtaining the engagement state of the cable connector based on the first pose transformation relationship and the second pose transformation relationship.

[0189] The processor-readable storage medium can be any available medium or data storage device that the processor can access, including but not limited to magnetic memory (e.g., floppy disk, hard disk, magnetic tape, magneto-optical disk (MO)), optical memory (e.g., CD, DVD, BD, HVD), and semiconductor memory (e.g., ROM, EPROM, EEPROM, non-volatile memory (NAND FLASH), solid-state drive (SSD)).

[0190] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0191] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0192] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A method for detecting the engagement state of a cable connector, characterized in that, include: The shooting unit is calibrated to obtain the shooting unit parameters; The position is calibrated based on the shooting unit parameters to obtain the first pose transformation relationship between the shooting unit and the moving contact of the cable connector; Based on the shooting unit parameters, the elliptical contour formed by perspective transformation of the circular outline at the bottom of the cable connector stationary contact is elliptical corrected to obtain the second pose transformation relationship between the shooting unit and the cable connector stationary contact. The engagement state of the cable connector is obtained based on the first pose transformation relationship and the second pose transformation relationship; The step of performing position calibration based on the parameters of the imaging unit to obtain the first pose transformation relationship between the imaging unit and the moving contact includes: The position is calibrated according to the shooting unit parameters to obtain the fourth pose transformation relationship between the shooting unit and the calibration plate set on the stationary contact. Based on the fourth pose transformation relationship and the geometric parameters of the cable connector calibration component, the first pose transformation relationship is obtained.

2. The method for detecting the engagement state of a cable connector according to claim 1, characterized in that, The step of calibrating the shooting unit to obtain its shooting unit parameters includes: Based on a pre-set chessboard grid, acquire the image of the shooting unit corresponding to the chessboard grid; Obtain the actual coordinates of the chessboard grid and the corner coordinates of the image captured by the camera unit; Based on the real-world coordinates of the chessboard and the coordinates of the corner points, the third pose transformation relationship is obtained; Based on the third pose transformation relationship, the shooting unit parameters of the shooting unit are obtained.

3. The method for detecting the engagement state of a cable connector according to claim 2, characterized in that, The process of obtaining the shooting unit parameters of the shooting unit based on the third pose transformation relationship includes: Multiple sets of initial shooting unit parameters are obtained based on the third pose transformation relationship; The shooting unit parameters are obtained from multiple sets of initial shooting unit parameters using the maximum likelihood estimation method.

4. The method for detecting the engagement state of a cable connector according to claim 1, characterized in that, The step of performing elliptical correction processing on the elliptical contour formed by perspective transformation of the circular contour at the bottom of the stationary contact of the cable connector according to the shooting unit parameters, to obtain the second pose transformation relationship between the shooting unit and the stationary contact of the cable connector, includes: Obtain the initial elliptical contour formed by perspective transformation of the circular contour at the bottom of the stationary contact of the cable connector; The inverse perspective transformation matrix is ​​obtained based on the shooting unit parameters; Based on the inverse perspective transformation matrix, the initial elliptical contour is subjected to inverse perspective transformation to obtain the corrected elliptical contour; The second pose transformation relationship is obtained based on the circular contour and the modified elliptical contour.

5. The method for detecting the engagement state of a cable connector according to claim 1, characterized in that, Also includes: The first pose transformation relationship data is digitized to obtain the first pose transformation relationship data, and the first pose transformation relationship data is displayed on the preset position calibration interface; Based on the first pose transformation relationship and the second pose transformation relationship, the engagement state of the cable connector is displayed on a pre-set visual measurement interface.

6. A cable connector engagement status detection system, characterized in that, include: The camera unit is located at the cable connector engagement position; A shooting unit parameter acquisition unit, connected to the shooting unit, is used to calibrate the shooting unit and obtain the shooting unit parameters of the shooting unit; The first relationship acquisition unit is connected to the shooting unit parameter acquisition unit and is used to perform position calibration according to the shooting unit parameters to obtain the first pose transformation relationship between the shooting unit and the moving contact of the cable connector. The second relationship acquisition unit is connected to the shooting unit parameter acquisition unit and is used to perform ellipse correction processing on the ellipse contour formed by perspective transformation of the circular contour at the bottom of the cable connector stationary contact according to the shooting unit parameters, so as to obtain the second pose transformation relationship between the shooting unit and the cable connector stationary contact. The engagement state detection unit is connected to the first relationship acquisition unit and the second relationship acquisition unit, and is used to obtain the engagement state of the cable connector based on the first pose transformation relationship and the second pose transformation relationship. The step of performing position calibration based on the parameters of the imaging unit to obtain the first pose transformation relationship between the imaging unit and the moving contact includes: The position is calibrated according to the shooting unit parameters to obtain the fourth pose transformation relationship between the shooting unit and the calibration plate set on the stationary contact. Based on the fourth pose transformation relationship and the geometric parameters of the cable connector calibration component, the first pose transformation relationship is obtained.

7. A cable connector engagement status detection device, characterized in that, include: The shooting unit parameter acquisition module is used to calibrate the shooting unit and obtain the shooting unit parameters of the shooting unit. The first relationship acquisition module is used to perform position calibration based on the shooting unit parameters to obtain the first pose transformation relationship between the shooting unit and the moving contact of the cable connector; The second relationship acquisition module is used to perform elliptical correction processing on the elliptical contour formed by perspective transformation of the circular contour at the bottom of the static contact of the cable connector according to the shooting unit parameters, so as to obtain the second pose transformation relationship between the shooting unit and the static contact of the cable connector. The engagement state detection module is used to obtain the engagement state of the cable connector based on the first pose transformation relationship and the second pose transformation relationship. The first relationship acquisition module is further configured to: The position is calibrated according to the shooting unit parameters to obtain the fourth pose transformation relationship between the shooting unit and the calibration plate set on the stationary contact. Based on the fourth pose transformation relationship and the geometric parameters of the cable connector calibration component, the first pose transformation relationship is obtained.

8. An electronic device comprising a processor and a memory storing a computer program, characterized in that, When the processor executes the computer program, it implements the cable connector engagement state detection method according to any one of claims 1 to 5.

9. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements the cable connector engagement state detection method according to any one of claims 1 to 5.

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