Device and method for testing flowing performance of adhesive on surface of steel plate

Abstract

The invention relates to the technical field of adhesive performance testing, in particular to a device and method for testing the flowing performance of an adhesive on the surface of a steel plate. The device comprises a base platform with a gradienter and leveling feet, a steel plate connected with a hinge (including an angle sensor), a temperature control platform (including an electric heating element and a temperature sensor), a dispensing mold, a laser transmitter, a high-speed camera and a data analysis terminal, wherein an electric push rod drives the steel plate to adjust the angle. The method comprises the following steps: calibrating the level of a base, adjusting the angle between a steel plate and a camera, positioning a mold by laser, taking the mold after glue injection, and heating the steel plate to a target temperature by a temperature control platform; the high-speed camera collects flowing images and transmits the images to the terminal; and the terminal corrects image distortion and frame ROI (Region of Interest), segments and extracts a glue contour through a local adaptive threshold algorithm and a Suzuki algorithm, calculates the flow length, width and area, and generates a report containing a dynamic curve and temperature and angle data. And the problems of poor quantitative property and insufficient parameter controllability of the traditional test are solved.

Description

Technical Field

[0001] This invention relates to the field of adhesive performance testing technology, and in particular to a testing device and method for testing the flow performance of adhesives on steel plate surfaces. Background Technology

[0002] In modern industrial production, the flowability of adhesives on steel plate surfaces has a crucial impact on workability, final bonding quality, and appearance.

[0003] However, current research and testing methods for the flowability of adhesives on steel plate surfaces often focus only on measuring the final flow length of the adhesive. This single-dimensional measurement method cannot comprehensively and deeply capture the dynamic process of adhesive flow. This makes it difficult for construction personnel to accurately grasp the behavioral characteristics of the adhesive during construction, and consequently, to adjust construction process parameters in a timely and effective manner to ensure that the adhesive achieves the best bonding effect.

[0004] Existing devices for testing adhesive flowability struggle to achieve precise and flexible adjustment of the testing angle. Different construction scenarios often require simulating application at specific angles to accurately reflect the adhesive's flow performance in practical applications. However, existing devices cannot meet this diverse need, leading to significant discrepancies between test results and actual construction conditions. Regarding temperature control, existing testing devices lack precision and fail to simulate the complex and variable temperatures of real-world construction environments, resulting in inaccurate test results reflecting the true flowability of adhesives under different temperature conditions. The initial dimensions of the adhesive strip, including its width and thickness, also significantly impact adhesive flowability. Existing devices lack precision and flexibility in controlling these aspects, failing to adjust the initial strip dimensions flexibly according to different testing requirements, thus limiting comprehensive research on adhesive flowability under various initial conditions. Summary of the Invention

[0005] To address the technical problems of insufficient quantification and poor controllability in existing tests of the flowability of adhesives on steel plates, this invention provides a testing device and method for the flowability of adhesives on steel plates.

[0006] Therefore, the present invention provides the following technical solution: A testing device for the flow performance of adhesives on a steel plate surface includes a base platform, a hinge, an electric actuator, and a steel plate. The fixed end of the hinge is fixedly mounted on the base platform, and the movable end of the hinge is connected to one edge of the steel plate. A scale is provided on one side of the hinge, and an angle sensor is mounted on the hinge's pivot. A temperature control platform is fixedly mounted on the bottom of the steel plate, and a dispensing mold is placed on the top of the steel plate. The cylinder end of the electric actuator is rotatably connected to the base platform via a pin, and the output end of the electric actuator is rotatably connected to the side of the steel plate away from the hinge via a pin. A high-speed camera is positioned in front of the side of the steel plate facing the operating side, and the high-speed camera is connected to a data analysis terminal via a data cable.

[0007] Furthermore, the dispensing mold has a bottomless frame structure, with its horizontal part at the top and its vertical part at the bottom. The ends of the two parts are respectively joined together and set at right angles, and the horizontal part and the vertical part enclose each other to form a channel for receiving adhesive.

[0008] Furthermore, it also includes a frame and a laser emitter, the laser emitter being mounted on the frame and located directly above the dispensing mold; a level is mounted on the base platform, and leveling feet are threaded onto the bottom of the base platform.

[0009] Furthermore, the temperature control platform integrates an electric heating element and a temperature sensor, wherein both the electric heating element and the temperature sensor are electrically connected to the control unit of the temperature control platform; the electric heating element is thermally conductively connected to the steel plate; and the electric heating element is a heating film or a PTC.

[0010] Furthermore, a stop is installed on the base platform at the end of the steel plate near the hinge.

[0011] A method for testing the flow properties of an adhesive on a steel plate surface, comprising the following steps: Observe the level indicator and adjust the leveling feet to ensure that the base platform is level; The tilt angle of the steel plate is adjusted using an electric push rod, and the angle of the high-speed camera is adjusted according to the tilt angle of the steel plate. A laser emitter is used to project a cross-shaped laser spot onto a steel plate, and a dispensing mold is placed at the corresponding laser spot position. Inject adhesive into the dispensing mold; After the adhesive is injected, remove the dispensing mold; A temperature control platform is used to heat the steel plate and adhesive to bring the adhesive to the required temperature. A high-speed camera is used to photograph the flow area of ​​the adhesive, and the resulting image data is transmitted to a data analysis terminal. The data analysis terminal uses pre-calibrated camera parameters to correct perspective distortion in the input image; based on the corrected image, it uses the geometric features of the cross laser spot emitted by the laser emitter to determine the position and tilt angle of the steel plate and define the ROI region required for flow analysis; it performs brightness and contrast normalization on the image sequence within the ROI region, and then performs grayscale processing on the normalized image. The adhesive and background pixels in the grayscale image are segmented using a local adaptive thresholding algorithm and binarization rules to obtain the adhesive contour. Establish a steel plate coordinate system, and calculate the flow length, flow width, and flow area for each frame or a set time interval of the image; The test report is obtained based on the flow length, flow width, and flow area.

[0012] Furthermore, the pre-calibrated camera parameters include the intrinsic parameter matrix K, the rotation matrix R, and the translation vector T. The calculation formula for perspective distortion correction of the input image is as follows:

[0013] In the formula: u is the horizontal coordinate of the pixel in the image plane; v is the vertical coordinate of the pixel in the image plane; the intrinsic parameter matrix K includes the focal length parameter and the principal point coordinate parameter; the rotation matrix R represents the rotation relationship of the camera coordinate system relative to the X, Y, and Z axes of the world coordinate system.

[0014] Furthermore, the normalized image is converted to grayscale using the following formula:

[0015] In the formula: Gray is the grayscale value; R is the red channel value; G is the green channel value; B is the blue channel value; The calculation formula for the local adaptive threshold algorithm is as follows:

[0016] In the formula: T() is the local adaptive threshold function; For pixels around The mean gray level of the region; C is a constant, C ; The binarization rule is as follows: If Gray(u,v)>T(u,v), then it is determined to be the background; otherwise, it is determined to be the adhesive strip. Output a binary image. Based on the 8-neighborhood connectivity criterion, the Suzuki algorithm is used to traverse the binary image and extract the contours of all connected regions to obtain the contour set of the adhesive. C n It is a sequence of pixel coordinates; Calculate the contour area A, circularity, and matching degree based on the obtained contour set. The formula for calculating the contour area A is as follows:

[0017] In the formula: u n u n+1 Let v be the coordinates of the nth and (n+1)th pixels in the contour set in the horizontal direction of the image plane; n+1 v n Let be the coordinates of the (n+1)th and nth pixels in the contour set in the vertical direction of the image plane; The formula for calculating circularity is as follows:

[0018] In the formula: Perimeter is the perimeter of the profile; The contour of the connected region with the smallest difference in area from the dispensing mold contour is selected, and the contour of the connected region with the largest roundness is selected as the initial contour of the adhesive.

[0019] Furthermore, the steel plate coordinate system is established with the downward slope direction of the steel plate's inclination angle as the flow direction of the adhesive, and the direction perpendicular to this flow direction and parallel to the steel plate surface as the transverse direction. In the steel plate coordinate system, calculate the farthest distance between the farthest point of the connected region contour in the flow direction and its initial contour to obtain the flow length of the adhesive; Draw a straight line parallel to the lateral direction on the contour of the connected region. The length of the line segment where the line intersects the contour of the connected region is the maximum flow width. Calculate the average value of all such line segment lengths to obtain the average flow width. The total number of white pixels in the binary image is counted, and the actual area is converted according to the camera's calibration parameters to obtain the flow area of ​​the adhesive.

[0020] Furthermore, before performing the observation of the level and adjusting the leveling feet, the following steps are also included: Clean the steel plate with alcohol or propanol; Use a pipette to apply the rust-preventive oil to the cleaned steel plate; Apply the rust-preventive oil evenly to the steel plate using a hard rubber roller, with an oil application amount of 3... 0.2 ; Place the steel plate horizontally in a desiccator and let it stand for 24 hours. The steel plate, after being left to stand, is installed on the base platform of the testing device.

[0021] Advantages and positive effects of the present invention: The device uses an electric push rod in conjunction with a hinge, along with an angle sensor on the hinge shaft, to precisely adjust and monitor the tilt angle of the steel plate in real time, solving the problem of inflexible angle control in traditional devices. The temperature control platform fixed at the bottom of the steel plate can precisely regulate the temperature of the steel plate, and with the operating space that can simulate the actual construction environment, it can achieve dual precise control of key parameters such as temperature and angle. At the same time, the glue dispensing mold on the top of the steel plate can standardize the initial width and thickness of the glue strip, ensuring that the initial size of the glue strip is consistent for each test, completely improving the shortcomings of traditional devices in terms of inaccurate and inflexible control of key parameters.

[0022] The high-speed camera on the front of the operating side of the steel plate is linked with the data analysis terminal to record the entire process of the adhesive from initial flow to stabilization in real time. With the help of the scale on the hinge side for positioning, dynamic data such as initial flow time, flow rate at different time points, and changes in flow length can be accurately obtained. This makes up for the limitation of traditional methods that can only measure the final flow length, and realizes full-cycle quantitative analysis of flow performance. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention 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 the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the structure of a testing device for the flow performance of adhesives on steel plate surfaces provided by the present invention.

[0025] Figure 2 A schematic diagram of the dispensing mold structure of a testing device for the flow performance of adhesives on steel plate surfaces provided by the present invention.

[0026] Figure 3 A flowchart of a method for testing the flow performance of an adhesive on a steel plate surface, provided by the present invention.

[0027] Figure 4 The image shows a physical example of an adhesive flow performance test method provided by this invention for testing the flow performance of adhesives on steel plate surfaces.

[0028] Figure 5 The image shows a physical example of an adhesive flow performance test method provided by this invention for testing the flow performance of adhesives on steel plate surfaces.

[0029] Figure 6 The image shows a physical example of an adhesive flow performance test method provided by this invention for testing the flow performance of an adhesive on a steel plate surface.

[0030] In the diagram: 101, base platform; 102, level; 103, leveling feet; 104, electric push rod; 105, steel plate; 106, dispensing mold; 107, laser emitter; 108, high-speed camera; 109, temperature control platform; 110, data analysis terminal; 111, stop block; 112, horizontal section; 113, vertical section; 114, channel. Detailed Implementation

[0031] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0032] This invention provides a testing device for the flow performance of adhesives on steel plate surfaces, such as... Figure 1 As shown, the system includes a base platform 101, a hinge, an electric actuator 104, and a steel plate 105. A level 102 is mounted on the base platform 101, and a leveling foot 103 is threaded onto the bottom of the base platform 101. By observing the level 102 on the base platform 101 and rotating the leveling foot 103 connected to the bottom thread, the base platform 101 can be adjusted to a horizontal state. This avoids measurement errors in the angle of the steel plate 105 due to base tilt and ensures that the flow direction is consistent with the direction of gravity. The fixed end of the hinge is fixedly installed on the base platform 101, and the movable end of the hinge is connected to one edge of the steel plate 105. The hinge has a scale on one side, and an angle sensor is installed on the hinge's pivot. A temperature control platform 109 is fixedly installed at the bottom of the steel plate 105, and a glue mold 106 is placed on the top of the steel plate 105. The cylinder end of the electric push rod 104 is rotatably connected to the base platform 101 via a pin, and the output end of the electric push rod 104 is rotatably connected to the side of the steel plate 105 away from the hinge via a pin. A high-speed camera 108 is located in front of the side of the steel plate 105 facing the operation side, and the high-speed camera 108 is connected to the data analysis terminal 110 via a data cable. According to the testing requirements, the steel plate 105 is driven to rotate around the hinge axis by the electric push rod 104. The angle sensor on the hinge axis provides real-time feedback on the tilt angle, which is verified by the scale on one side of the hinge until the steel plate 105 reaches the target tilt angle. At the same time, the angle of the high-speed camera 108 is adjusted so that its lens is facing the flow area of ​​the steel plate 105 to ensure that the shooting range completely covers the possible flow path of the adhesive.

[0033] The temperature control platform 109 integrates a heating element and a temperature sensor, both of which are electrically connected to the control unit of the temperature control platform 109; the heating element is thermally conductively connected to the steel plate 105; the heating element is a heating film or a PTC heater. Figure 2 As shown, the dispensing mold 106 has a bottomless frame structure, with its horizontal portion 112 at the top and its vertical portion 113 at the bottom. The ends of the two portions are joined together at right angles, and the horizontal portion 112 and the vertical portion 113 enclose a channel 114 for receiving adhesive. It also includes a frame and a laser emitter 107, which is mounted on the frame and located directly above the dispensing mold 106. The control unit of the temperature control platform 109 is activated, and the heating element (heating film / PTC) heats the steel plate 105 through heat conduction. The temperature sensor collects the steel plate temperature in real time and feeds it back to the control unit, forming a closed-loop control until the steel plate 105 reaches the set temperature. Simultaneously, the laser emitter 107 is activated, causing its emitted cross-shaped laser spot to fall on the pre-applied adhesive area of ​​the steel plate 105. The dispensing mold 106 is placed corresponding to the laser spot position, and the channel 114 of the mold is used to determine the initial width and thickness of the adhesive strip, ensuring consistent adhesive application.

[0034] A stop 111 is installed on the base platform 101 at the end of the steel plate 105 near the hinge. The stop 111 blocks the steel plate 105 to prevent it from moving.

[0035] A test method for the flow properties of adhesives on steel plate surfaces, such as... Figure 3 As shown, it includes the following steps: Clean the steel plate with alcohol or propanol.

[0036] Use a pipette to apply rust-preventive oil to the cleaned steel plate.

[0037] Apply the rust-preventive oil evenly to the steel plate using a hard rubber roller, with an oil application amount of 3... 0.2 .

[0038] Place the steel plate horizontally in a desiccator and let it stand for 24 hours.

[0039] The steel plate, after being left to stand, is installed on the base platform of the testing device.

[0040] Observe the level indicator and adjust the leveling feet to ensure that the base platform is level.

[0041] The tilt angle of the steel plate is adjusted using an electric push rod, and the angle of the high-speed camera is adjusted according to the tilt angle of the steel plate.

[0042] A laser emitter is used to project a cross-shaped laser spot onto a steel plate, and a dispensing mold is placed at the corresponding laser spot position.

[0043] Inject adhesive into the dispensing mold.

[0044] After the adhesive is injected, remove the dispensing mold.

[0045] A temperature control platform is used to heat the steel plate and adhesive to bring the adhesive to the required temperature.

[0046] A high-speed camera is used to photograph the flow area of ​​the adhesive, and the resulting image data is transmitted to a data analysis terminal. The high-speed camera can be set to take pictures automatically at fixed time intervals (such as every 5 seconds, 30 seconds, or 1 minute).

[0047] The data analysis terminal uses pre-calibrated camera parameters to correct perspective distortion in the input image. Based on the corrected image, it uses the geometric features of the cross laser spot emitted by the laser emitter to determine the position and tilt angle of the steel plate and define the ROI region required for flow analysis. The ROI, or Region of Interest, specifically refers to the core analysis area in the image that contains only the adhesive flow process. Irrelevant parts such as the steel plate edge and background are excluded to reduce the "invalid data" in subsequent algorithm processing and reduce the computational cost of data processing. The image sequence within the ROI region is normalized for brightness and contrast, and the normalized image is then converted to grayscale.

[0048] The pre-calibrated camera parameters include the intrinsic parameter matrix K, the rotation matrix R, and the translation vector T. The calculation formula for perspective distortion correction of the input image is as follows:

[0049] In the formula: u is the horizontal coordinate of the pixel in the image plane; v is the vertical coordinate of the pixel in the image plane; the intrinsic parameter matrix K includes the focal length parameter and the principal point coordinate parameter; the rotation matrix R represents the rotation relationship of the camera coordinate system relative to the X, Y, and Z axes of the world coordinate system.

[0050] The image after normalization is converted to grayscale using the following formula:

[0051] In the formula: Gray is the grayscale value; R is the red channel value; G is the green channel value; B is the blue channel value.

[0052] The adhesive and background pixels in the grayscale image are segmented using a local adaptive thresholding algorithm and binarization rules to obtain the adhesive contour.

[0053] The calculation formula for the local adaptive threshold algorithm is as follows:

[0054] In the formula: T() is the local adaptive threshold function; For pixels around The mean gray level of the region; C is a constant, C .

[0055] The binarization rules are as follows: If Gray(u,v)>T(u,v), then it is determined to be the background; otherwise, it is determined to be the adhesive strip. Output a binary image.

[0056] Based on the 8-neighborhood connectivity criterion, the Suzuki algorithm is used to traverse the binary image and extract the contours of all connected regions to obtain the contour set of the adhesive. C n It is a sequence of pixel coordinates.

[0057] Calculate the contour area A, circularity, and matching degree based on the obtained contour set. The formula for calculating the contour area A is as follows:

[0058] In the formula: u n u n+1 Let v be the coordinates of the nth and (n+1)th pixels in the contour set in the horizontal direction of the image plane; n+1 v n Let be the coordinates of the (n+1)th and nth pixels in the contour set in the vertical direction of the image plane; The formula for calculating circularity is as follows:

[0059] In the formula: Perimeter is the perimeter of the profile; The contour of the connected region with the smallest area difference from the dispensing mold outline is selected, along with the contour of the connected region with the highest roundness. The connected region contour that simultaneously satisfies the conditions of smallest area difference and highest roundness is used as the initial contour of the adhesive. This initial contour is the contour when the adhesive has not flowed. The area and size data of the dispensing mold can be entered in advance according to the testing requirements.

[0060] The flow direction of the adhesive is defined by the downward slope of the steel plate's inclination angle, and the direction perpendicular to the flow direction and parallel to the steel plate surface is defined as the transverse direction. A steel plate coordinate system is established, and the flow length, flow width, and flow area are calculated for each frame or a set time interval of the image.

[0061] In the steel plate coordinate system, calculate the farthest distance between the farthest point of the connected region contour in the flow direction and its initial contour to obtain the flow length of the adhesive; Draw a straight line parallel to the lateral direction on the contour of the connected region. The length of the line segment where the line intersects the contour of the connected region is the maximum flow width. Calculate the average value of all such line segment lengths to obtain the average flow width. The total number of white pixels in the binary image is counted, and the actual area is converted according to the camera's calibration parameters to obtain the flow area of ​​the adhesive.

[0062] The test report is generated based on the flow length, flow width, and flow area. The test report includes flow length-time curves, flow rate-time curves, flow area-time curves, flow width-time curves, temperature data from the temperature control platform, and inclination angle data of the steel plate.

[0063] Compare the test results with the evaluation criteria in the table below to determine whether the flow performance of the adhesive on the surface of the current steel plate sample meets the standard.

[0064] Table of Smoothness Evaluation Criteria for Different Types of Adhesives at Different Temperatures

[0065] Example 1: The test steel plate model is DC54D+Z; the steel plate thickness is 1.5mm; the adhesive is spot welding sealant SS; the steel plate tilt angle is 70°; the heating temperature is 170℃; the heating time is 20min; the data collection time is 10min and 20min.

[0066] The test results are shown in the table below. Figure 4 As shown: Test results table for Example 1

[0067] in This refers to the deformation length of the adhesive in the transverse direction; This represents the deformation length of the adhesive in the vertical direction.

[0068] The test results of Example 1 show that, and All are less than 3mm, which meets the flowability requirements for construction.

[0069] Case 2: The test steel plate model was HC340LAD+Z; the steel plate thickness was 1.5mm; the adhesive was shock-absorbing expansion adhesive MS-1b; the steel plate tilt angle was 30°; the temperature was 25℃; the heating time was 20min; and the data collection time was 10min and 20min.

[0070] The test results are shown in the table below. Figure 5 As shown: Test results table for Example 2

[0071] The test results of Example 2 show that, and All are less than 5mm, which meets the flowability requirements for construction.

[0072] Case 3: The test steel plate model is DC54D+Z; the steel plate thickness is 1.5mm; the adhesive is structural adhesive 1850C; the steel plate tilt angle is 50°; the heating temperature is 160℃; the heating time is 20min; the data collection time is 10min and 20min.

[0073] The test results are shown in the table below. Figure 6 As shown: Test results table for Example 3

[0074] The test results of Example 3 show that, and All are less than 3mm, which meets the flowability requirements for construction.

[0075] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention 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 or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A testing device for the flow performance of adhesives on steel plate surfaces, characterized in that, The system includes a base platform (101), a hinge, an electric push rod (104), and a steel plate (105). The fixed end of the hinge is fixedly installed on the base platform (101), and the movable end of the hinge is connected to one edge of the steel plate (105). The hinge has a scale on one side, and an angle sensor is installed on the hinge's shaft. A temperature control platform (109) is fixedly installed at the bottom of the steel plate (105), and a glue mold (106) is placed on the top of the steel plate (105). The cylinder end of the electric push rod (104) is rotatably connected to the base platform (101) via a pin, and the output end of the electric push rod (104) is rotatably connected to the side of the steel plate (105) away from the hinge via a pin. A high-speed camera (108) is located in front of the side of the steel plate (105) facing the operation side, and the high-speed camera (108) is connected to a data analysis terminal (110) via a data cable.

2. The testing device for the flow performance of adhesives on steel plate surfaces according to claim 1, characterized in that, The dispensing mold (106) has a bottomless frame structure, with its horizontal part (112) located above and its vertical part (113) located below. The ends of the two parts are respectively connected and set at right angles. The horizontal part (112) and the vertical part (113) enclose each other to form a channel (114) for receiving adhesive.

3. The testing device for the flow performance of adhesives on steel plate surfaces according to claim 1, characterized in that, It also includes a frame and a laser emitter (107), which is mounted on the frame and located directly above the dispensing mold (106); a level (102) is mounted on the base platform (101), and a leveling foot (103) is threaded onto the bottom of the base platform (101).

4. The testing device for the flow performance of adhesives on steel plate surfaces according to claim 1, characterized in that, The temperature control platform (109) integrates an electric heating element and a temperature sensor, wherein the electric heating element and the temperature sensor are electrically connected to the control unit of the temperature control platform (109); the electric heating element is thermally conductively connected to the steel plate (105); the electric heating element is a heating film or PTC.

5. The testing device for the flow performance of adhesives on steel plate surfaces according to claim 1, characterized in that, A stop (111) is installed on the base platform (101) and at the end of the steel plate (105) near the hinge.

6. A method for testing the flow performance of an adhesive on a steel plate surface, implemented using a testing device for the flow performance of an adhesive on a steel plate surface according to any one of claims 1-5, characterized in that, Includes the following steps: Observe the level indicator and adjust the leveling feet to ensure that the base platform is level; The tilt angle of the steel plate is adjusted using an electric push rod, and the angle of the high-speed camera is adjusted according to the tilt angle of the steel plate. A laser emitter is used to project a cross-shaped laser spot onto a steel plate, and a dispensing mold is placed at the corresponding laser spot position. Inject adhesive into the dispensing mold; After the adhesive is injected, remove the dispensing mold; A temperature control platform is used to heat the steel plate and adhesive to bring the adhesive to the required temperature. A high-speed camera is used to photograph the flow area of ​​the adhesive, and the resulting image data is transmitted to a data analysis terminal. The data analysis terminal uses pre-calibrated camera parameters to correct perspective distortion in the input image; based on the corrected image, it uses the geometric features of the cross laser spot emitted by the laser emitter to determine the position and tilt angle of the steel plate and define the ROI region required for flow analysis; it performs brightness and contrast normalization on the image sequence within the ROI region, and then performs grayscale processing on the normalized image. The adhesive and background pixels in the grayscale image are segmented using a local adaptive thresholding algorithm and binarization rules to obtain the adhesive contour. Establish a steel plate coordinate system, and calculate the flow length, flow width, and flow area for each frame or a set time interval of the image; The test report is obtained based on the flow length, flow width, and flow area.

7. The method for testing the flow performance of an adhesive on a steel plate surface according to claim 6, characterized in that, The pre-calibrated camera parameters include the intrinsic parameter matrix K, the rotation matrix R, and the translation vector T. The calculation formula for perspective distortion correction of the input image is as follows: In the formula: u is the horizontal coordinate of the pixel in the image plane; v is the vertical coordinate of the pixel in the image plane; the intrinsic parameter matrix K includes the focal length parameter and the principal point coordinate parameter; the rotation matrix R represents the rotation relationship of the camera coordinate system relative to the X, Y, and Z axes of the world coordinate system.

8. The method for testing the flow performance of an adhesive on a steel plate surface according to claim 6, characterized in that, The normalized image is then converted to grayscale using the following formula: In the formula: Gray is the grayscale value; R is the red channel value; G is the green channel value; B is the blue channel value; The calculation formula for the local adaptive threshold algorithm is as follows: In the formula: T() is the local adaptive threshold function; For pixels around The mean gray level of the region; C is a constant, C ; The binarization rule is as follows: If Gray(u,v)>T(u,v), then it is determined to be the background; otherwise, it is determined to be the adhesive strip. Output a binary image. Based on the 8-neighborhood connectivity criterion, the Suzuki algorithm is used to traverse the binary image and extract the contours of all connected regions to obtain the contour set of the adhesive. C n It is a sequence of pixel coordinates; Calculate the contour area A, circularity, and matching degree based on the obtained contour set. The formula for calculating the contour area A is as follows: In the formula: u n u n+1 Let v be the coordinates of the nth and (n+1)th pixels in the contour set in the horizontal direction of the image plane; n+1 v n Let be the coordinates of the (n+1)th and nth pixels in the contour set in the vertical direction of the image plane; The formula for calculating circularity is as follows: In the formula: Perimeter is the perimeter of the profile; The contour of the connected region with the smallest difference in area from the dispensing mold contour is selected, and the contour of the connected region with the largest roundness is selected as the initial contour of the adhesive.

9. A method for testing the flow performance of an adhesive on a steel plate surface according to claim 6, characterized in that, The steel plate coordinate system is established with the downward slope direction of the steel plate's inclination angle as the flow direction of the adhesive, and the direction perpendicular to the flow direction and parallel to the steel plate surface as the transverse direction. In the steel plate coordinate system, calculate the farthest distance between the farthest point of the connected region contour in the flow direction and its initial contour to obtain the flow length of the adhesive; Draw a straight line parallel to the lateral direction on the contour of the connected region. The length of the line segment where the line intersects the contour of the connected region is the maximum flow width. Calculate the average value of all such line segment lengths to obtain the average flow width. The total number of white pixels in the binary image is counted, and the actual area is converted according to the camera's calibration parameters to obtain the flow area of ​​the adhesive.

10. A method for testing the flow performance of an adhesive on a steel plate surface according to claim 6, characterized in that, Before observing the level and adjusting the leveling feet, the following steps are also included: Clean the steel plate with alcohol or propanol; Use a pipette to apply the rust-preventive oil to the cleaned steel plate; Apply the rust-preventive oil evenly to the steel plate using a hard rubber roller, with an oil application amount of 3... 0.2 ; Place the steel plate horizontally in a desiccator and let it stand for 24 hours. The steel plate, after being left to stand, is installed on the base platform of the testing device.

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