Visual calibration and computation method

Abstract

The application relates to a visual calibration and calculation method, which comprises the following steps: visual calibration: calibrating the mutual positions of a plurality of 3D visual modules arranged uniformly in the circumferential direction and establishing a coordinate system; scanning and imaging: each 3D visual module respectively scans and images a product to be measured; forming a contour: fitting each image to form a complete contour required to be measured; taking pairs of cross-section points: taking a plurality of pairs of cross-section points on the circumferential contours of the upper and lower molds on the product to be measured; obtaining a first group of center points; obtaining a second group of center points; adjusting an angle: according to the first group of center points and the second group of center points, guiding a machine table to adjust the angle of the product to be measured; adjusting XY: guiding a platform to adjust the product to be measured in the XY direction. The application can detect and adjust in real time until the product to be measured is adjusted to the required numerical range, and repeated adjustment and detection are not required.

Description

Technical Field

[0001] This invention relates to the field of visual calibration calculation technology, and in particular to a visual calibration and calculation method. Background Technology

[0002] During the headphone manufacturing process, after the outer shell is assembled, it needs to be glued and cured under pressure. Before glue application and curing, it is necessary to ensure that the upper and lower shells of the headphone are precisely aligned. In existing technologies, the upper and lower shells of the headphone are adjusted in multiple directions using an adjustment mechanism, and the adjusted positions are then scanned and inspected by a detection mechanism. However, existing technologies cannot achieve automated adjustment, often requiring repeated adjustments and inspections, and they cannot guarantee the accuracy of the adjustment and inspection. Summary of the Invention

[0003] The purpose of this invention is to provide a visual calibration and calculation method to alleviate the problems of existing technologies that cannot achieve automated adjustment, often require repeated adjustment and detection, and cannot guarantee the accuracy of adjustment and detection.

[0004] To achieve this objective, the present invention adopts the following technical solution: A visual calibration and calculation method includes the following steps: Visual calibration: Calibrate the relative positions of multiple 3D visual modules evenly arranged along the circumference and establish a coordinate system; Scanning and image acquisition: Each 3D vision module scans and acquires images of the product under test; Contour Formation: Fitting individual images together to form the complete contour that needs to be measured; Take a pair of cross-sectional points: Take a number of pairs of cross-sectional points on the circumferential contours of the upper and lower modules of the product to be tested; Obtain the first set of center points: Generate two ellipses, the upper module and the lower module, through several pairs of cross-section points, and obtain the center points of the two ellipses, C1 and H1; The second set of center points is obtained by offsetting the base surface by 1mm above and below, and calculating the two ellipse center points C2 and H2. Adjusting the angle: Based on the first set of center points and the second set of center points, guide the machine to adjust the angle of the product to be tested; Adjust XY: Guide the adjustment platform to perform fine-tuning of the XY direction of the product under test.

[0005] Preferably, in the visual calibration step, a spherical calibration block is placed at the center of multiple 3D vision modules, the machine scans the outline of the spherical calibration block, and the relative positions of multiple 3D vision modules are calibrated and a coordinate system is established based on the scanning results.

[0006] Preferably, in the contour forming step, point cloud data is stitched together according to the established coordinate system to form a graphic with 360-degree XYZ information.

[0007] As a preferred method, in the step of obtaining the first set of center points, the joint between the upper module and the lower module is located to form an annular baseline. At 0.2mm above and below the baseline, the contour point cloud of the product to be tested is extracted to form two ellipses.

[0008] As a preferred method, in the angle adjustment step, C1C2 is connected to obtain the straight line CL, H1H2 is connected to obtain the straight line HL, the angle between CL and HL is calculated, and the machine is guided to adjust the angle of the product to be tested based on the obtained angle data.

[0009] As a preferred option, in the XY adjustment step, the adjustment platform is guided to perform fine-tuning of the XY direction of the product under test based on the step values ​​of multiple points on the circumferential contour at the docking point between the upper and lower modules.

[0010] Preferably, the step value includes the step height difference and the horizontal drop.

[0011] As a preferred option, in the XY adjustment step, different adjustment distances are selected based on the different values ​​of the fine-tuning of the XY direction steps.

[0012] Preferably, when the step fine-tuning value in the XY direction is greater than or equal to 0.05, double the moving distance is used; when the step fine-tuning value in the XY direction is greater than or equal to 0.02 and less than 0.05, 1.3 times the moving distance is used.

[0013] Preferably, material feeding is performed when the step fine-tuning value in the XY direction is less than 0.02.

[0014] The beneficial effects of this invention are: The visual calibration and calculation method includes the following steps: Visual calibration: calibrating the relative positions of multiple 3D vision modules evenly arranged circumferentially and establishing a coordinate system; Scanning and image acquisition: each 3D vision module scans and acquires images of the product under test; Contour formation: fitting the images together to form the complete contour to be measured; Taking pairs of cross-sectional points: taking several pairs of cross-sectional points on the circumferential contours of the upper and lower modules of the product under test; Obtaining the first set of center points: generating two ellipses for the upper and lower modules using the several pairs of cross-sectional points, and obtaining the center points of the two ellipses C1 and H1; Obtaining the second set of center points: offsetting 1mm above and below the base surface, calculating the center points of the two ellipses C2 and H2; Adjusting the angle: guiding the machine to adjust the angle of the product under test based on the first and second set of center points; Adjusting XY: guiding the adjustment platform to perform step fine adjustment of the product under test in the XY direction.

[0015] Visual calibration establishes a coordinate system for multiple 3D vision modules, then uses scanning to capture images and form a complete 360° product outline, improving inspection accuracy. By identifying cross-sectional points, obtaining the first set of center points, and obtaining the second set of center points, the machine can automatically adjust the angle of the product under test and guide the adjustment platform to perform step-by-step fine-tuning of the product under test in the XY directions, improving adjustment accuracy. Furthermore, it can detect and adjust in real time until the product under test is adjusted to the required value range, eliminating the need for repeated adjustments and inspections, thus improving production efficiency. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the content of the embodiments of the present invention and these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the overall process of the visual calibration and calculation method provided by the present invention. Detailed Implementation

[0018] Before explaining any implementation of this application in detail, it should be understood that this application is not limited to its application to the structural details and component arrangements set forth in the following description or shown in the above drawings.

[0019] In this application, the terms "comprising," "including," "having," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0020] In this application, the term "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent three cases: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this application generally indicates that the preceding and following related objects have an "and / or" relationship.

[0021] In this application, the terms "connection," "combination," "coupling," and "installation" can refer to direct connection, combination, coupling, or installation, or indirect connection, combination, coupling, or installation. For example, a direct connection refers to two parts or components being connected together without the need for an intermediary, while an indirect connection refers to two parts or components each being connected to at least one intermediary, with the connection achieved through the intermediary. Furthermore, "connection" and "coupling" are not limited to physical or mechanical connections or couplings, but can also include electrical connections or couplings.

[0022] In this application, those skilled in the art will understand that relative terms (e.g., “about,” “approximately,” “basically,” etc.) used in conjunction with quantities or conditions are to include the values ​​and have the meaning indicated by the context. For example, such relative terms include at least the degree of error associated with the measurement of a particular value, tolerances associated with the particular value due to manufacturing, assembly, use, etc. Such terms should also be considered as disclosing a range defined by the absolute values ​​of the two endpoints. Relative terms may refer to a certain percentage (e.g., 1%, 5%, 10% or more) of the indicated value. Numerical values ​​that do not use relative terms should also be disclosed as specific values ​​with tolerances. Furthermore, “basically” when expressing relative angular relationships (e.g., substantially parallel, substantially perpendicular) may refer to a certain degree (e.g., 1 degree, 5 degrees, 10 degrees or more) added to or subtracted from the indicated angle.

[0023] In this application, those skilled in the art will understand that the function performed by a component can be performed by one component, multiple components, one part, or multiple parts. Similarly, the function performed by a part can also be performed by one part, one component, or a combination of multiple parts.

[0024] In this application, the directional terms "upper," "lower," "left," "right," "front," and "rear" are used to describe the orientation and positional relationships shown in the accompanying drawings and should not be construed as limiting the embodiments of this application. Furthermore, in the context, it should be understood that when an element is mentioned as being connected "upper" or "lower" to another element, it can be directly connected to the other element "upper" or "lower," or indirectly connected through an intermediate element. It should also be understood that directional terms such as upper side, lower side, left side, right side, front side, and rear side not only represent positive orientation but can also be understood as lateral orientation. For example, "below" can include directly below, lower left, lower right, lower front, and lower rear.

[0025] Example 1 This invention provides a visual calibration and calculation method, see [link to relevant documentation]. Figure 1 The visual calibration and calculation method includes the following steps: The first step is visual calibration: calibrating the relative positions of multiple 3D visual modules evenly arranged along the circumference and establishing a coordinate system; The second step is scanning and image acquisition: each 3D vision module scans and acquires images of the product under test. The third step is to form the contour: fit the various images together to form the complete contour that needs to be measured. Step 4: Select a pair of cross-sectional points: Select a number of pairs of cross-sectional points on the circumferential contours of the upper and lower modules of the product to be tested; Fifth step, obtain the first set of center points: generate two ellipses, the upper module and the lower module, through several pairs of cross-section points, and obtain the center points of the two ellipses, C1 and H1; Step 6: Obtain the second set of center points: offset 1mm above and below the base surface, and calculate the two ellipse center points C2 and H2; Step 7, Adjust the angle: Based on the first set of center points and the second set of center points, guide the machine to adjust the angle of the product to be tested; Step 8, Adjust XY: Guide the adjustment platform to fine-tune the XY steps of the product under test.

[0026] Visual calibration establishes a coordinate system for multiple 3D vision modules, then uses scanning to capture images and form a complete 360° product outline, improving inspection accuracy. By identifying cross-sectional points, obtaining the first set of center points, and obtaining the second set of center points, the machine can automatically adjust the angle of the product under test and guide the adjustment platform to perform step-by-step fine-tuning of the product under test in the XY directions, improving adjustment accuracy. Furthermore, it can detect and adjust in real time until the product under test is adjusted to the required value range, eliminating the need for repeated adjustments and inspections, thus improving production efficiency.

[0027] In an optional embodiment, during the visual calibration step, a spherical calibration block is placed at the center of multiple 3D vision modules, the machine scans the outline of the spherical calibration block, and the relative positions of the multiple 3D vision modules are calibrated and a coordinate system is established based on the scanning results.

[0028] In this embodiment, the 3D vision module uses three 3D cameras, evenly distributed at 120° intervals, capable of detecting a 360° range around the product parting surface. Its main function is to detect the upper and lower modules of the product in real time, provide parameters through intelligent calculation, and guide automatic three-axis adjustment to align the upper and lower modules.

[0029] Specifically, first, the spherical calibration block is placed on the curing fixture, and then its position is adjusted to ensure that the spherical calibration block is centered on the three 3D cameras. Next, the calibration mode is selected on the controller, and the automatic mode is selected in the software. Finally, the machine runs automatically, scanning the 360° contour of the spherical calibration block, generating calibration results, and automatically calibrating the relative coordinate system of the three 3D cameras.

[0030] In an optional embodiment, during the contour forming step, point cloud data is stitched together according to the established coordinate system to form a graphic with 360-degree XYZ information.

[0031] Specifically, three 3D cameras each scan and capture images, and through calibration relationships, point cloud data is stitched together to form a graphic with 360-degree XYZ information. Then, 1000+ pairs of cross-sectional points are taken on the 360° contour of the upper and lower modules of the product under test (in this embodiment, the upper and lower shells of the earphone).

[0032] In an optional embodiment, in the step of obtaining the first set of center points, the seam between the upper and lower modules is located to form a ring-shaped baseline. At points 0.2 mm above and below this baseline, the contour point cloud of the product to be measured is captured, forming two ellipses. These two ellipses represent the positional information of the upper and lower modules. Using these two ellipses, two center points, C1 and H1, are obtained; these center points are the intersections of the major and minor sides of the ellipses. Then, by offsetting the base surface by 1 mm above and below, and using the same algorithm, two more ellipse center points, C2 and H2, are obtained.

[0033] In the optional method of this embodiment, in the angle adjustment step, C1C2 is connected to obtain the straight line CL, H1H2 is connected to obtain the straight line HL, the angle between CL and HL is calculated, and the machine is guided to adjust the angle of the product to be tested based on the obtained angle data.

[0034] In an optional embodiment, during the XY adjustment step, the adjustment platform is guided to perform fine-tuning of the XY direction of the product under test based on the step values ​​of multiple points on the circumferential contour at the docking point between the upper and lower modules.

[0035] Specifically, the step value includes the step height difference and the plane drop. After adjusting the angle, the step value is calculated based on the eight points around the perimeter, guiding the adjustment platform to fine-tune the steps of the product under test.

[0036] In this embodiment, the center of the upper module and the center of the lower module, as well as the major and minor semi-axes, are calculated using the least squares method. The XY guiding coordinates of the axis are obtained by the optimal solution of the center difference between the upper and lower modules and the eight step values ​​of the upper and lower modules. The Z guiding coordinates of the axis are obtained by the angle difference of the major axis between the upper and lower modules.

[0037] In the optional method of this embodiment, in the XY adjustment step, different adjustment distances are selected according to different values ​​of the fine adjustment of the XY direction steps.

[0038] Specifically, when the fine-tuning value of the XY direction step is greater than or equal to 0.05, double the movement distance is used; when the fine-tuning value of the XY direction step is greater than or equal to 0.02 and less than 0.05, 1.3 times the movement distance is used. When the fine-tuning value of the XY direction step is less than 0.02, material feeding is executed.

[0039] The overall alignment logic in this embodiment is to first adjust the angle and then adjust XY. When XY is greater than or equal to 0.05, double the moving distance is used; when XY is greater than or equal to 0.02 and less than 0.05, 1.3 times the moving distance is used; when XY is less than 0.02, material feeding is performed.

[0040] The visual calibration and calculation method of the present invention includes a series of steps such as visual calibration, scanning and image acquisition, contour formation, taking the correct cross-sectional points, obtaining the first set of center points, obtaining the second set of center points, adjusting the angle, and adjusting the XY.

[0041] The visual calibration and calculation method forms a complete 360° product outline through scanning detection, resulting in higher detection accuracy; the intelligent calculation guides the equipment to automatically adjust the product's position and angle; real-time detection and adjustment are performed until the product under test is adjusted to the required value range; after adjustment, the curing fixture is held until the relative positions of the upper and lower modules of the product are completely fixed; the adjustment accuracy is higher, and it can adjust in eight directions.

[0042] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A visual calibration and calculation method, characterized in that, Includes the following steps: Visual calibration: Calibrate the relative positions of multiple 3D visual modules evenly arranged along the circumference and establish a coordinate system; Scanning and image acquisition: Each 3D vision module scans and acquires images of the product under test; Contour Formation: Fitting individual images together to form the complete contour that needs to be measured; Take a pair of cross-sectional points: Take a number of pairs of cross-sectional points on the circumferential contours of the upper and lower modules of the product to be tested; Obtain the first set of center points: Generate two ellipses, the upper module and the lower module, through several pairs of cross-section points, and obtain the center points of the two ellipses, C1 and H1; The second set of center points is obtained by offsetting the base surface by 1mm above and below, and calculating the two ellipse center points C2 and H2. Adjusting the angle: Based on the first set of center points and the second set of center points, guide the machine to adjust the angle of the product to be tested; Adjust XY: Guide the adjustment platform to perform fine-tuning of the XY direction of the product under test.

2. The visual calibration and calculation method according to claim 1, characterized in that, In the visual calibration step, a spherical calibration block is placed at the center of multiple 3D vision modules. The machine scans the outline of the spherical calibration block, and the relative positions of the multiple 3D vision modules are calibrated and a coordinate system is established based on the scanning results.

3. The visual calibration and calculation method according to claim 1, characterized in that, In the contour formation step, point cloud data is stitched together according to the established coordinate system to form a graphic with 360-degree XYZ information.

4. The visual calibration and calculation method according to claim 1, characterized in that, In the first step of obtaining the center point, the joint between the upper and lower modules is located to form a ring-shaped baseline. At 0.2mm above and below the baseline, the outline point cloud of the product to be tested is extracted to form two ellipses.

5. The visual calibration and calculation method according to claim 1, characterized in that, In the angle adjustment step, connect C1C2 to obtain the straight line CL, connect H1H2 to obtain the straight line HL, calculate the angle between CL and HL, and guide the machine to adjust the angle of the product to be tested based on the obtained angle data.

6. The visual calibration and calculation method according to claim 1, characterized in that, In the XY adjustment step, the adjustment platform is guided to perform fine-tuning of the XY direction of the product under test based on the step values ​​of multiple points on the circumferential contour at the docking point between the upper and lower modules.

7. The visual calibration and calculation method according to claim 6, characterized in that, The step value includes the step height difference and the horizontal drop.

8. The visual calibration and calculation method according to claim 1, characterized in that, During the XY adjustment process, different adjustment distances are selected based on the different values ​​of the XY step fine-tuning.

9. The visual calibration and calculation method according to claim 8, characterized in that, When the step adjustment value in the XY direction is greater than or equal to 0.05, use double the movement distance; when the step adjustment value in the XY direction is greater than or equal to 0.02 and less than 0.05, use 1.3 times the movement distance.

10. The visual calibration and calculation method according to claim 9, characterized in that, When the step fine-tuning value in the XY direction is less than 0.02, the material feeding is executed.

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