Laser vision calibration method and device for photovoltaic cell equipment

Abstract

The invention discloses a photovoltaic cell equipment laser vision calibration method and device, and the method comprises the steps that a laser system carves a preset calibration graph on a calibration piece according to a loaded target file, and the target file comprises path information of laser carved on the calibration piece under the control of a laser board card; the calibration graph comprises calibration lines arranged in parallel; collecting a grayscale image of the calibration line in the detection area through an industrial camera, and positioning the position of the calibration line after processing the grayscale image; fitting calibration is carried out on the positioned calibration line position in each detection area on the calibration piece and the calibration line actual position, and a calibration result is obtained; and verifying the calibration result, and determining the angle value of the laser motion axis and the target position of the laser motion axis when the photovoltaic cell is produced based on the calibration result.

Description

Technical Field

[0001] The present application relates to the field of visual calibration, and more specifically, to a method and apparatus for laser visual calibration of photovoltaic cell equipment. Background Art

[0002] In the production process of photovoltaic cells, laser processing is increasingly being used, such as laser grooving, laser heavy doping, laser etching, and laser transfer.

[0003] During laser processing, a scanning galvanometer can be used to control the laser scanning along a preset processing path, or a motion device can be used to drive the laser head along the preset processing path. Due to the high precision requirements for photovoltaic cell processing, the galvanometer or motion device needs to be calibrated. In the existing technology, calibration of the laser axial motion and angle control during laser scanning is lacking. Summary of the Invention

[0004] In response to at least one defect or improvement need in the prior art, the present invention provides a laser vision calibration method and device for photovoltaic cell equipment, which solves the problem of insufficient calibration accuracy when calibrating the position and angle of the laser axis during photovoltaic equipment production, and achieves the goals of high precision, high efficiency and high stability in the production of photovoltaic equipment.

[0005] To achieve the above-mentioned purpose, according to a first aspect of the present invention, a method for laser vision calibration of photovoltaic cell equipment is provided, the method comprising: a laser system engraving a predetermined calibration pattern on a calibration part according to a loaded target file, wherein the target file contains path information for a laser board to control the laser to engrave on the calibration part; the calibration pattern comprises parallel calibration lines; an industrial camera is used to capture a grayscale image of the calibration line in a detection area, and the position of the calibration line is located after image processing of the grayscale image; the calibration line position in each detection area on the located calibration part and the actual position of the calibration line are fitted and calibrated to obtain a calibration result; the calibration result is verified, and based on the calibration result, the angle value of the laser motion axis and the target position of the laser motion axis during photovoltaic cell production are determined.

[0006] In an exemplary embodiment, engraving predetermined calibration lines on the calibration part after loading the target file includes: the laser system loads the target file to obtain predetermined monomask parameters, and controls the laser to continuously engrave on the calibration part according to the monomask parameters to obtain N parallel calibration lines; and records the laser motion axis position and laser motion axis angle corresponding to each of the N calibration lines.

[0007] In an exemplary embodiment, the method of acquiring grayscale images of calibration lines in the detection area by an industrial camera and locating the position of the calibration lines after image processing of the grayscale images includes: acquiring grayscale images of the calibration lines in the detection area by multiple industrial cameras, wherein, among the multiple industrial cameras, every two cameras are correspondingly arranged at the two ends of the calibration lines in a detection area; performing distortion correction processing on the multiple cameras and calibrating the calibration plate, and converting the camera image coordinate systems corresponding to the multiple cameras into the same calibration plate coordinate system; locating the centerline position of each calibration line after image processing of the grayscale image, and determining the centerline position of the calibration line as the calibration line position.

[0008] In an exemplary embodiment, performing image processing on the grayscale image includes performing threshold processing on the grayscale image using a Sauvola local binarization algorithm. The Sauvola binarization formula is:

[0009]

[0010] Wherein, g(i,j) is the grayscale value at the pixel point (x,y) in the grayscale image, r is the neighborhood radius, m(x,y) is the pixel grayscale mean with r as the radius, s(x,y) is the grayscale variance of the neighborhood of the pixel point, k is the coefficient, R is the dynamic range of the standard deviation, and T(x,y) is the binarization threshold of the pixel point (x,y).

[0011] In an exemplary embodiment, the calibration line positions in each detection area on the calibration part that is positioned and the actual positions of the calibration lines are fitted and calibrated to obtain calibration results, including: determining the perpendicular bisector of each calibration line at each laser motion axis angle to obtain a series of perpendicular bisectors; extending the series of perpendicular bisectors, and determining the intersection point fitted after extension as the laser rotation center point; using the least squares method to fit and calculate the position coordinates of the laser rotation center point to obtain the anchor point position.

[0012] In an exemplary embodiment, after determining the perpendicular bisector of each calibration line at each laser motion axis angle to obtain a series of perpendicular bisectors, the method further includes calculating an average value of the series of perpendicular bisectors at the current laser motion axis angle using the following formula: in, is the average value of all bisector slopes at the current laser motion axis angle, is the mean of all perpendicular bisector intercepts at the current laser motion axis angle; by setting different calibration laser motion axis angle values, the mean of the perpendicular bisector corresponding to the calibration line at each laser motion axis angle is calculated. and The perpendicular bisectors under all laser motion axis angles are extended to fit a common intersection point, and the position coordinates of the laser rotation center are calculated using the least squares fitting method to obtain the anchor point position (x c ,y c ), the position coordinate formula of the laser rotation center point is determined as follows:

[0013]

[0014] Where n is the angle of the n-th laser motion axis.

[0015] In an exemplary embodiment, after calculating the position coordinates of the laser rotation center point using the least squares fitting method to obtain the anchor point position, the method further includes: calculating the vertical distance from the anchor point position to the position of each calibration line, performing linear fitting on the laser motion axis coordinate values ​​corresponding to the vertical distance and the calibration line position to obtain a first fitting relationship, and the calculation formula is: y m =k m x m +b m , where x m is the distance from the anchor point to the calibration line, y m is the laser motion axis position (coordinate value) corresponding to the calibration line, k m and b m is the fitting parameter; the least squares method is used to linearly fit each laser motion axis angle with the laser angle value in the calibration coordinate system after the grayscale image is calibrated to obtain the second fitting relationship, and the calculation formula is T=K×Ang+B, wherein K and B are fitting coefficients, and Ang is the corresponding laser angle value under the laser motion axis angle T.

[0016] In an exemplary embodiment, after linearly fitting the laser angle values ​​in the calibration coordinate system after calibrating each laser angle with the grayscale image using the least squares method to obtain a second fitting relationship, the method further includes: determining the target position of the laser motion axis in the production equipment during photovoltaic cell production based on the first fitting parameter in the first fitting relationship; and determining the laser angle value of the target processing line positioned in each detection area during photovoltaic cell production at the current laser motion axis angle based on the second fitting parameter in the second fitting relationship.

[0017] In an exemplary embodiment, the determining of the target position of the laser motion axis in the production equipment during photovoltaic cell production based on the first fitting parameter in the first fitting relationship includes calculating the laser rotation center point (x c ,y c ) to the distance X from the line to be processed j , according to the fitting parameter km 、b m Calculate the actual target position Y of the laser motion axis j , the calculation formula is, Y j =k m X j +b m , where Y j is the laser axis motion position corresponding to the line to be processed; the second fitting parameter in the second fitting relationship is used to determine the laser angle value of the target processing line at the current laser motion axis angle during photovoltaic cell production, including positioning the angle value Ang of the line to be processed in each area during photovoltaic cell equipment production. j , calculate the laser angle value T of the processing line at the current laser motion axis angle based on the fitting parameters K and B j , the calculation formula is, T j =K×Ang j +B, where T j The current laser motion axis angle value.

[0018] According to the second aspect of the present invention, a laser vision calibration device for photovoltaic cell equipment is also provided, which includes: an engraving unit, which is used for the laser system to engrave a predetermined calibration pattern on the calibration part according to a loaded target file, wherein the target file contains path information for the laser board to control the laser to engrave on the calibration part; the calibration pattern includes parallel calibration lines; a positioning unit, which is used to capture the grayscale image of the calibration line in the detection area through an industrial camera, and locate the position of the calibration line after image processing of the grayscale image; a calibration unit, which is used to fit and calibrate the calibration line position in each detection area on the positioned calibration part and the actual position of the calibration line to obtain a calibration result; a first determination unit, which is used to verify the calibration result, and determine the angle value of the laser motion axis and the target position of the laser motion axis during photovoltaic cell production based on the calibration result.

[0019] According to a third aspect of the present invention, a computer-readable storage medium is further provided, in which a computer program is stored, wherein the computer program is configured to execute the above-mentioned photovoltaic cell device laser vision calibration method when running.

[0020] According to a fourth aspect of the present invention, an electronic device is also provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the above-mentioned photovoltaic cell device laser vision calibration method through the computer program.

[0021] In general, the above technical solutions conceived by the present invention can achieve the following beneficial effects compared with the prior art:

[0022] This invention provides a laser vision calibration method for photovoltaic cell equipment. This method uses a laser board to load a monomask file, engraves specific calibration lines on a calibration component, then uses an industrial camera to capture a grayscale image of the calibration lines. After image processing, the calibration lines are located. The calibration line positions in each region are then fitted and calibrated with the actual laser positions. Finally, the calibration results are verified and used during production. By calibrating the laser axis position and angle during photovoltaic equipment production, the method achieves high precision, high efficiency, and high stability in photovoltaic equipment production. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0024] Figure 1 A schematic flow chart of an optional laser vision calibration method for photovoltaic cell equipment provided in an embodiment of the present application;

[0025] Figure 2 A schematic flow chart of another optional photovoltaic cell device laser vision calibration method provided in an embodiment of the present application;

[0026] Figure 3 A schematic diagram of an optional laser vision calibration method for photovoltaic cell equipment provided in an embodiment of the present application;

[0027] Figure 4 A schematic diagram of a laser motion axis and laser motion axis angle for an optional laser vision calibration method for a photovoltaic cell device provided in an embodiment of the present application;

[0028] Figure 5 A schematic structural diagram of an optional photovoltaic cell device laser vision calibration device provided in an embodiment of the present application;

[0029] Figure 6 A schematic structural diagram of an optional electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0030] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0031] The terms "first," "second," "third," and the like in the specification and claims of this application and the accompanying drawings are used to distinguish between different objects, not to describe a particular order. Furthermore, the terms "including," "having," and any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus comprising a series of steps or elements is not limited to the listed steps or elements but may optionally include steps or elements not listed, or may optionally include other steps or elements inherent to the process, method, product, or apparatus.

[0032] According to one aspect of the embodiment of the present application, a method for laser vision calibration of photovoltaic cell equipment is provided. Figure 1 The present invention describes a method for laser vision calibration of photovoltaic cell equipment provided in an embodiment of the present application.

[0033] Figure 1 This is a flow chart of an optional laser vision calibration method for photovoltaic cell equipment provided in an embodiment of the present application, such as Figure 1 As shown, the process of the method may include the following steps:

[0034] S102, the laser system engraves a predetermined calibration pattern on the calibration part according to the loaded target file, wherein the target file includes path information for the laser board to control the laser to engrave on the calibration part; the calibration pattern includes parallel calibration lines;

[0035] S104, capturing a grayscale image of the calibration line in the detection area using an industrial camera, performing image processing on the grayscale image, and locating the position of the calibration line;

[0036] S106, performing fitting calibration on the calibration line position in each detection area on the located calibration piece and the actual position of the laser engraving path to obtain a calibration result;

[0037] S108 , verifying the calibration result, and determining the angle value of the laser motion axis and the target position of the laser motion axis during photovoltaic cell production based on the calibration result.

[0038] An optional photovoltaic cell device laser vision calibration method provided in this application can be used to calibrate the position and angle of the laser motion axis during photovoltaic device production.

[0039] In this embodiment, Figure 2 A schematic diagram of a flow chart of another optional photovoltaic cell device laser vision calibration method provided in an embodiment of the present application, combined with Figure 1 and Figure 2As shown in the figure, during the process of calibrating the position and angle of the laser motion axis during photovoltaic equipment production, a laser board can optionally be used to load a monomask file to engrave a specific calibration pattern on the calibration component. In other words, a specific file (monomask file) can be used to control the laser board to engrave parallel calibration lines on the calibration component for calibration. This method ensures the accuracy and consistency of the calibration lines, providing a foundation for subsequent image acquisition and processing.

[0040] It should be noted that a laser board generally refers to an electronic board with integrated laser control functions, responsible for controlling the laser's on / off light, modulation, positioning, and synchronization. A monomask file, on the other hand, is a laser parameter file that contains information about the position and duration of laser engraving to create specific patterns or lines.

[0041] After engraving a specific calibration pattern on the calibration part, the grayscale image of the calibration pattern in the detection area can be collected by an industrial camera, and the position of the calibration line can be located in the image processing. Specifically, the image with the calibration line can be collected by an industrial camera, and then the position of the calibration line can be located using image processing technology. Optionally, image processing technology can include edge detection, feature extraction, etc. to ensure that the position of the calibration line can be accurately identified and located. The calibration line position of each area and the actual position of the laser can then be fitted and calibrated. That is to say, after determining the position of the calibration line, these positions need to be fitted with the actual position of the laser to achieve calibration. After the calibration is completed, the results need to be verified to ensure that they meet production requirements. The verification process can include accuracy detection, that is, comparing the difference between the measured value and the actual value to evaluate the accuracy of the calibration.

[0042] Through the above steps S102 to S108, a predetermined calibration pattern is engraved on the calibration part by the laser system according to the loaded target file, wherein the target file contains the path information of the laser board controlling the laser to engrave on the calibration part, and the calibration pattern includes parallel calibration lines; the grayscale image of the calibration line in the detection area is collected by the industrial camera, and the position of the calibration line is located after image processing of the grayscale image; the calibration line position in each detection area on the located calibration part and the actual position of the laser are fitted and calibrated to obtain a calibration result; the calibration result is verified, and based on the calibration result, the angle value of the laser motion axis and the target position of the laser motion axis during photovoltaic cell production are determined, thereby solving the problem of calibrating the position and angle of the laser motion axis during photovoltaic equipment production and achieving the purpose of high-precision photovoltaic equipment production.

[0043] In an exemplary embodiment, engraving a predetermined calibration pattern on the calibration part after loading the target file includes:

[0044] S11, the laser system loads the target file to obtain the predetermined monomask parameters, and controls the laser to continuously engrave on the calibration part according to the monomask parameters to obtain N parallel calibration lines;

[0045] S12, recording the laser motion axis position and the laser motion axis angle corresponding to each of the N calibration lines.

[0046] In the embodiment of this application, Figure 3 A schematic diagram of an optional laser vision calibration method for photovoltaic cell equipment provided in an embodiment of the present application is shown as follows: Figure 3 As shown, optionally, the laser device can engrave the calibration piece. By loading specific monomask parameters, the laser system can control the laser to continuously engrave on the calibration piece according to the monomask parameters. Optionally, the calibration piece can be aluminum foil.

[0047] After the laser engraves the calibration part, N calibration lines are obtained, which can provide more reference points for visual calibration, thereby improving the accuracy of the calibration. For subsequent calibration verification, the laser motion axis position and laser motion axis angle corresponding to each of the N calibration lines can also be recorded. By recording the laser motion axis position and the laser motion axis, a comparative analysis can be performed in the subsequent calibration verification to verify the accuracy of the calibration results. Through this embodiment, the production quality of photovoltaic cells can be improved through precise laser engraving and calibration, and the laser processing process of the cell can be made more accurate, reducing waste and improving cell efficiency, while improving the stability and consistency of production.

[0048] In an exemplary embodiment, capturing a grayscale image of a calibration pattern in a detection area by an industrial camera, and locating the calibration line after performing image processing on the grayscale image includes:

[0049] S21, collecting a grayscale image of a calibration pattern in a detection area using multiple industrial cameras, wherein two of the multiple industrial cameras are correspondingly set at two ends of a calibration line in one detection area;

[0050] S22, performing distortion correction processing on the multiple cameras and calibrating the calibration plate, and converting the camera image coordinate systems corresponding to the multiple cameras into the same calibration plate coordinate system;

[0051] S23 , after performing image processing on the grayscale image, the centerline position of each calibration line is located, and the centerline position of the calibration line is determined as the calibration line position.

[0052] In the embodiment of this application, Figure 3 As shown, when locating the calibration line position, in order to increase the acquisition accuracy of the industrial camera, multiple groups of industrial cameras can be set to acquire grayscale images of the calibration graphics. Figure 3It includes 4 groups of industrial cameras, corresponding to 4 detection areas. Among them, at both ends (L end and R end) of each detection area, two industrial cameras are correspondingly arranged at both ends of the corresponding calibration line. That is, the grayscale images of both ends of the calibration line in one detection area collected under the field of view of the industrial cameras can be obtained through every two industrial cameras. After performing distortion correction processing on the 8 cameras, calibration of the calibration board is carried out simultaneously, and the connection between the camera image coordinate systems can be established by converting to the same calibration board coordinate system.

[0053] When performing image processing, specifically, the image can be filtered and subjected to morphological processing. Here, a 5×5 rectangular mean filter template can be used for filtering, and a 30×1 kernel can be used for the closing operation method in morphological processing. Furthermore, the sauvola local binary thresholding algorithm can be used to perform thresholding on the image, setting the pixel points higher than the threshold to 0 and the pixel points lower than the threshold to 255. The sauvola binary formula is as follows:

[0054]

[0055] Among them, g(x,y) is the grayscale value at the image pixel point (x,y), r is the neighborhood radius, m(x,y) is the mean grayscale value of the pixels with r as the radius at the pixel point (x,y), s(x,y) is the grayscale variance of the neighborhood of this pixel point, k is a coefficient 0<k<1, here k is taken as 0.2, R is the dynamic range of the standard deviation, the image is an 8-bit grayscale image, here R = 128, and T(x,y) is the binary threshold of the point (x,y).

[0056] Optionally, the Binary Large Object Analysis (BLOB) can be used to binary the image, locate the area of each calibration line, find and locate the left and right edges of each calibration line in the original grayscale image, take the midline of the left and right edge lines, further locate the position of the midline of the calibration line, and determine this position as the calibration line position.

[0057] In an exemplary embodiment, the positions of the calibration lines in each detection area on the located calibration piece and the actual positions of the lasers are fitted and calibrated, and the obtained calibration results include:

[0058] S31, determining the perpendicular bisectors of each calibration line at each laser movement axis angle, obtaining a series of perpendicular bisectors;

[0059] S32, extending a series of perpendicular bisectors, and determining the intersection point obtained by the extension after fitting as the laser rotation center point;

[0060] S33, using the least squares method to fit and calculate the position coordinates of the laser rotation center point to obtain the anchor point position.

[0061] In the embodiment of the present application, in the process of fitting and calibrating the calibration line position of each area and the actual laser position, optionally, at each laser motion axis angle curT (i.e., at each current laser angle), the calibration line position of each camera positioning can be converted to the same calibration plate coordinate system. By taking the calibration line position coordinates of the cameras at both ends of each area, the coordinates of each calibration line are connected as the calibration line position, and the center point of the calibration line is calculated. A perpendicular bisector y = kx + b is drawn for each calibration line, and the average value of the bisector at the current laser motion axis angle is calculated. The calculation formula is as follows:

[0062]

[0063] in, is the average value of the slopes of all bisectors at the curT angle (i.e. the current laser motion axis angle), is the mean of all bisector intercepts at angle curT.

[0064] By setting different calibration laser motion axis angle values ​​Ti, the average value of the laser corresponding bisector at each laser motion axis angle is calculated. and The bisectors at all laser motion axis angles are extended and fitted to find a common intersection point, which is determined as the laser rotation center point. The formula is as follows:

[0065]

[0066] Among them, n is the angle of the nth laser motion axis. Further, the least squares method can be used to fit and calculate the rotation center position (x c ,y c ). Set the rotation center position (x c ,y c ) as the anchor point position.

[0067] In an exemplary embodiment, after calculating the position coordinates of the laser rotation center point using the least squares fitting method to obtain the anchor point position, the method further includes:

[0068] S41, calculating the vertical distance from the anchor point position to the position of each calibration line, and performing linear fitting on the laser motion axis coordinate values ​​corresponding to the vertical distance and the calibration line position to obtain a first fitting relationship;

[0069] S42, using the least square method to perform linear fitting on each laser motion axis angle and the laser angle value in the calibration coordinate system after the grayscale image is calibrated, to obtain a second fitting relationship.

[0070] In this embodiment of the present application, after determining the coordinates of the anchor point position, the vertical distance from the anchor point to the final position of each calibration line can be calculated. This vertical distance is linearly related to the position of the laser motion axis. A linear fit is then performed on the vertical distance from each calibration line in each region to the anchor point and the position of the laser motion axis to obtain a first fitting relationship, which is calculated as follows:

[0071] y m =k m x m +b m

[0072] Among them, x m is the distance from the anchor point to the calibration line, y m is the laser motion axis position (coordinate value) corresponding to the calibration line, k m and b m is the fitting parameter.

[0073] Similarly, the calibration line images engraved at different laser motion axis angles T can be calibrated using a calibration plate, and the laser angle Ang in the corresponding calibration coordinate system can be calculated. The two are linearly related (that is, the second fitting relationship can be calculated). The corresponding coefficients are fitted using the least squares method, and the formula is as follows:

[0074] T=K×Ang+B

[0075] Among them, K and B are fitting coefficients. The corresponding laser angle Ang values ​​under all laser motion axis angles T are counted and K and B can be calculated using the least squares method.

[0076] See also Figure 4 , which is a schematic diagram of the laser motion axis and the laser motion axis angle.

[0077] In an exemplary embodiment, after linear fitting is performed on each laser motion axis angle and the laser angle value in the calibration coordinate system after the grayscale image is calibrated using the least squares method to obtain a second fitting relationship, the method further includes:

[0078] S51, determining a target position of a laser motion axis in a production device during photovoltaic cell production based on a first fitting parameter in the first fitting relationship;

[0079] S52 , determining a laser angle value of a target processing line at a current laser motion axis angle during photovoltaic cell production based on a second fitting parameter in the second fitting relationship.

[0080] In this embodiment, the calibration result can be verified and used in production, that is, the first fitting relationship and the second fitting relationship determined in the above embodiment can be used for verification calculation.

[0081] Optionally, the calibration results can be verified. After each laser angle calibration, the fitting parameters of the four regions converge to a certain range, and the b-value fluctuation range index is within 800, which meets the set accuracy requirements. The calibration results are verified to ensure that the angle difference index of the calibration line positioned by the cameras at both ends of each region is within 0.08°, and the angle difference index of the final center line of the laser positioned by the cameras in the four regions is within 0.1°, which meets the set accuracy requirements.

[0082] Furthermore, the target processing line (i.e., the line to be processed) angle value Ang of each area can be located during the production of photovoltaic cell equipment. j , calculate the actual laser motion axis angle value T by fitting parameters K and B j (i.e., the angle value of the laser motion axis), which is calculated as follows:

[0083] T j =K×Ang j +B

[0084] Among them, T j The current laser motion axis angle value.

[0085] Similarly, the rotation center (x c ,y c ) to the distance X from the line to be processed j , by the fitting parameter k m 、b m Calculate the actual target position Y of the laser motion axis j (i.e., the target position of the laser motion axis), which is calculated as follows:

[0086] Y j =k m X j +b m

[0087] Among them, Y j is the laser axis motion position corresponding to the line to be processed.

[0088] The angle and position of the line to be processed can be determined by identifying the mark point of the workpiece to be processed. This is a prior art and will not be expanded here.

[0089] The line to be processed can be determined according to the processing requirements of photovoltaic cells. For example, for laser re-doping of solar cells, the line to be processed is the medium-doped area on the cell. For laser grooving and laser etching, the line to be processed is the area to be grooved and etched. For laser transfer, the line to be processed is the groove on the source substrate.

[0090] Through this embodiment, by verifying the calibration results, it can be ensured that the measuring equipment provides accurate measurement results within the specified error range, and it can be ensured that the measurement and control in the production process are more precise, thereby improving the quality of the final photovoltaic cell production products.

[0091] According to another aspect of the embodiments of the present application, a laser vision calibration device for implementing the above-mentioned photovoltaic cell device laser vision calibration method is also provided. Figure 5 FIG. 1 is a schematic structural diagram of an optional photovoltaic cell device laser vision calibration device according to an embodiment of the present application, such as Figure 5 As shown, the device may include:

[0092] The engraving unit 502 is configured to cause the laser system to engrave a predetermined calibration pattern on the calibration object according to a loaded target file, wherein the target file includes path information for the laser board to control the laser to engrave on the calibration object; the calibration pattern includes parallel calibration lines;

[0093] A positioning unit 504 is configured to capture a grayscale image of the calibration line in the detection area using an industrial camera, and locate the position of the calibration line after performing image processing on the grayscale image;

[0094] The calibration unit 506 is configured to perform fitting calibration on the calibration line positions in each detection area on the calibration member and the actual positions of the calibration lines to obtain a calibration result;

[0095] The first determining unit 508 is configured to verify the calibration result and determine the angle value of the laser motion axis and the target position of the laser motion axis during photovoltaic cell production based on the calibration result.

[0096] It should be noted that the engraving unit 502 in this embodiment can be used to execute the above step S102, the positioning unit 504 in this embodiment can be used to execute the above step S104, the calibration unit 506 in this embodiment can be used to execute the above step S106, and the first determination unit 508 in this embodiment can be used to execute the above step S108.

[0097] Through the above module, the laser system engraves a predetermined calibration pattern on the calibration part according to the loaded target file, wherein the target file contains the path information of the laser board controlling the laser to engrave on the calibration part; the calibration pattern includes parallel calibration lines; the grayscale image of the calibration line in the detection area is collected by an industrial camera, and the position of the calibration line is located after image processing of the grayscale image; the position of the calibration line in each detection area on the located calibration part and the actual position of the calibration line are fitted and calibrated to obtain the calibration result; the calibration result is verified, and based on the calibration result, the angle value of the laser motion axis and the target position of the laser motion axis during photovoltaic cell production are determined, thereby solving the problem of insufficient calibration accuracy when calibrating the position and angle of the laser axis during photovoltaic equipment production, and achieving the purpose of high precision, high efficiency and high stability in photovoltaic equipment production.

[0098] In an exemplary embodiment, the engraving unit comprises:

[0099] An engraving module is used for the laser system to load the target file to obtain predetermined monomask parameters, and to control the laser to continuously engrave on the calibration piece according to the monomask parameters to obtain N parallel calibration lines;

[0100] The recording module is used to record the laser motion axis position and the laser engraving angle corresponding to each of the N calibration lines.

[0101] In an exemplary embodiment, the positioning unit comprises:

[0102] an acquisition module, configured to acquire a grayscale image of the calibration line in the detection area through a plurality of industrial cameras, wherein every two of the plurality of industrial cameras are correspondingly arranged at two ends of a calibration line in one detection area;

[0103] a conversion module, configured to perform distortion correction processing on the multiple cameras and perform calibration on a calibration plate, and convert the camera image coordinate systems corresponding to the multiple cameras into the same calibration plate coordinate system;

[0104] The first determination module is configured to locate the centerline position of each calibration line after performing image processing on the grayscale image, and determine the centerline position of the calibration line as the calibration line position.

[0105] In an exemplary embodiment, the first determining module includes,

[0106] The processing submodule is used to perform threshold processing on the grayscale image using the Sauvola local binarization algorithm. The Sauvola binarization formula is:

[0107]

[0108] Wherein, g(i,j) is the grayscale value at the pixel point (x,y) in the grayscale image, r is the neighborhood radius, m(x,y) is the pixel grayscale mean with r as the radius, s(x,y) is the grayscale variance of the neighborhood of the pixel point, k is the coefficient, R is the dynamic range of the standard deviation, and T(x,y) is the binarization threshold of the pixel point (x,y).

[0109] In an exemplary embodiment, the calibration unit includes:

[0110] The second determination module is used to determine the perpendicular bisector of each calibration line at each laser motion axis angle to obtain a series of perpendicular bisectors;

[0111] A third determining module is configured to extend the series of perpendicular bisectors and determine an intersection point obtained by fitting the extended lines as the laser rotation center point;

[0112] The calculation module is used to calculate the position coordinates of the laser rotation center point using the least squares fitting method to obtain the anchor point position.

[0113] In an exemplary embodiment, the apparatus further comprises:

[0114] The first calculation unit is used to calculate the average value of a series of perpendicular bisectors under the current laser motion axis angle. The calculation formula is: in, is the average value of all bisector slopes at the current laser motion axis angle, is the mean of all perpendicular bisector intercepts at the current laser motion axis angle;

[0115] The second calculation unit is used to calculate the average value of the perpendicular bisector corresponding to the calibration line at each laser motion axis angle by setting different calibration laser motion axis angle values. and

[0116] The third calculation unit is used to extend the perpendicular bisectors under all laser motion axis angles to fit a common intersection point, and use the least squares method to fit and calculate the position coordinates of the laser rotation center point to obtain the anchor point position (x c ,y c ), the position coordinate formula of the laser rotation center point is determined as follows:

[0117]

[0118] Where n is the angle of the n-th laser motion axis.

[0119] In an exemplary embodiment, the apparatus further comprises:

[0120] The first fitting unit is used to calculate the vertical distance from the anchor point position to the position of each calibration line, and perform linear fitting on the vertical distance and the laser motion axis coordinate value corresponding to the calibration line position to obtain a first fitting relationship. The calculation formula is: m =k m x m +b m , where x m is the distance from the anchor point to the calibration line, y m is the laser motion axis position (coordinate value) corresponding to the calibration line, k m and b m is the fitting parameter;

[0121] The second fitting unit is used to use the least squares method to perform linear fitting on each laser motion axis angle and the laser angle value in the calibration coordinate system after the grayscale image is calibrated to obtain a second fitting relationship. The calculation formula is T=K×Ang+B, where K and B are fitting coefficients, and Ang is the corresponding laser angle value under the laser motion axis angle T.

[0122] In an exemplary embodiment, the apparatus further comprises:

[0123] a second determining unit, configured to determine a target position of a laser motion axis in a production device during photovoltaic cell production based on a first fitting parameter in the first fitting relationship;

[0124] The third determining unit is configured to determine, based on the second fitting parameter in the second fitting relationship, a laser angle value of a target processing line positioned in each detection area during photovoltaic cell production at a current laser motion axis angle.

[0125] In an exemplary embodiment, the second determining unit includes,

[0126] The first calculation module is used to calculate the laser rotation center point (x c ,y c ) to the distance X from the line to be processed j , according to the fitting parameter k m 、b m Calculate the actual target position Y of the laser motion axis j , the calculation formula is, Y j =k m X j +b m , where Y j is the laser axis motion position corresponding to the line to be processed;

[0127] The third determining unit includes a second calculating module for locating the angle value Ang of the line to be processed of each area during the production of the photovoltaic cell equipment.j , calculate the laser angle value T of the processing line at the current laser motion axis angle based on the fitting parameters K and B j , the calculation formula is, T j =K×Ang j +B, where T j The current laser motion axis angle value.

[0128] It should be noted here that the examples and scenarios implemented by the above modules and corresponding steps are the same, but are not limited to the contents disclosed in the above embodiments. It should be noted that the above modules as part of the device can run in a hardware environment, can be implemented by software, and can also be implemented by hardware, where the hardware environment includes a network environment.

[0129] According to another aspect of the embodiments of the present application, a storage medium is further provided. Optionally, in this embodiment, the storage medium can be used to execute the program code of any of the above-mentioned photovoltaic cell device laser vision calibration methods in the embodiments of the present application.

[0130] Optionally, in this embodiment, the storage medium is configured to store program codes for executing the following steps:

[0131] S1, the laser system engraves a predetermined calibration pattern on the calibration part according to the loaded target file, wherein the target file contains the path information of the laser board controlling the laser to engrave on the calibration part; the calibration pattern includes parallel calibration lines;

[0132] S2, using an industrial camera to collect a grayscale image of the calibration line in the detection area, and locating the calibration line after image processing on the grayscale image;

[0133] S3, performing fitting calibration on the calibration line position in each detection area on the located calibration piece and the actual position of the calibration line to obtain a calibration result;

[0134] S4, verifying the calibration result, and determining the angle value of the laser motion axis and the target position of the laser motion axis during photovoltaic cell production based on the calibration result.

[0135] Optionally, the specific examples in this embodiment may refer to the examples described in the above embodiments, which will not be described in detail in this embodiment.

[0136] Among them, computer-readable storage media may include, but are not limited to, any type of disk, including floppy disks, optical disks, DVDs, CD-ROMs, microdrives and magneto-optical disks, ROMs, RAMs, EPROMs, EEPROMs, DRAMs, VRAMs, flash memory devices, magnetic or optical cards, nanosystems (including molecular memory ICs), or any type of medium or device suitable for storing instructions and / or data.

[0137] According to another aspect of the embodiments of the present application, an electronic device for implementing the above-mentioned photovoltaic cell equipment laser vision calibration method is also provided. The electronic device can be a server, a terminal, or a combination thereof.

[0138] Figure 6 is a schematic structural diagram of an optional electronic device according to an embodiment of the present application, such as Figure 6 As shown, it includes a processor 602, a communication interface 604, a memory 606 and a communication bus 608, wherein the processor 602, the communication interface 604, and the memory 606 communicate with each other via the communication bus 608, wherein,

[0139] Memory 606, for storing computer programs;

[0140] The processor 602 is configured to execute the computer program stored in the memory 606 to implement the following steps:

[0141] S1, the laser system engraves a predetermined calibration pattern on the calibration part according to the loaded target file, wherein the target file contains the path information of the laser board controlling the laser to engrave on the calibration part; the calibration pattern includes parallel calibration lines;

[0142] S2, using an industrial camera to collect a grayscale image of the calibration line in the detection area, and locating the calibration line after image processing on the grayscale image;

[0143] S3, performing fitting calibration on the calibration line position in each detection area on the located calibration piece and the actual position of the calibration line to obtain a calibration result;

[0144] S4, verifying the calibration result, and determining the angle value of the laser motion axis and the target position of the laser motion axis during photovoltaic cell production based on the calibration result.

[0145] Optionally, the communication bus may be a PCI (Peripheral Component Interconnect) bus or an EISA (Extended Industry Standard Architecture) bus. The communication bus may be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 6 The communication interface is used for communication between the electronic device and other devices.

[0146] The memory may include RAM, or may include non-volatile memory, such as at least one disk memory. Alternatively, the memory may also be at least one storage device located away from the aforementioned processor.

[0147] As an example, the memory 606 may include, but is not limited to, the engraving unit 502, positioning unit 504, calibration unit 506, and first determination unit 508 of the photovoltaic cell device laser vision calibration device. Furthermore, the memory 606 may also include, but is not limited to, other module units of the photovoltaic cell device laser vision calibration device, which are not further described in this example.

[0148] The above-mentioned processor can be a general-purpose processor, which can include but is not limited to: CPU (Central Processing Unit), NP (Network Processor), etc.; it can also be DSP (Digital Signal Processing), ASIC (Application Specific Integrated Circuit), FPGA (Field-Programmable Gate Array) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.

[0149] Optionally, the specific examples in this embodiment may refer to the examples described in the above embodiments, and this embodiment will not be described in detail here.

[0150] It should be noted that for the aforementioned method embodiments, for the sake of simplicity, they are all expressed as a series of action combinations, but those skilled in the art should be aware that this application is not limited by the order of the actions described, because according to this application, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by this application.

[0151] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0152] In the several embodiments provided in this application, it should be understood that the disclosed devices can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some service interface, and the indirect coupling or communication connection of the device or unit can be electrical or other forms.

[0153] The units described as separate components may or may not be physically separate, and 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 these units may be selected to achieve the purpose of the solution of this embodiment according to actual needs.

[0154] In addition, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0155] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable memory. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a memory, including a number of instructions for enabling a computer device (which can be a personal computer, server or network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned memory includes: various media that can store program codes, such as a USB flash drive, a read-only memory (ROM), a random access memory (RAM), a mobile hard disk, a magnetic disk or an optical disk.

[0156] A person skilled in the art will understand that all or part of the steps in the various methods of the above embodiments can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable memory, which may include: a flash drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, etc.

[0157] The above is only an exemplary embodiment of the present disclosure and cannot be used to limit the scope of the present disclosure. That is, any equivalent changes and modifications made according to the teachings of the present disclosure are still within the scope of the present disclosure. After considering the specification and practicing the disclosure herein, those skilled in the art will easily think of the implementation scheme of the present disclosure. This application is intended to cover any variation, use or adaptation of the present disclosure, which follows the general principles of the present disclosure and includes common knowledge or customary technical means in the art that are not recorded in the present disclosure. The description and examples are to be regarded as exemplary only, and the scope and spirit of the present disclosure are defined by the claims.

[0158] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0159] It will be easily understood by those skilled in the art that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A laser vision calibration method for photovoltaic cell equipment, characterized in that: include: The laser system engraves a predetermined calibration pattern on the calibration piece according to the loaded target file, wherein the target file includes path information for the laser board to control the laser to engrave on the calibration piece; the calibration pattern includes parallel calibration lines; The industrial camera is used to collect a grayscale image of the calibration line in the detection area, and the grayscale image is processed to locate the position of the calibration line; Performing fitting calibration on the calibration line positions in each detection area on the located calibration piece and the actual positions of the calibration lines to obtain a calibration result; The calibration result is verified, and based on the calibration result, the angle value of the laser motion axis and the target position of the laser motion axis during photovoltaic cell production are determined.

2. The laser vision calibration method for photovoltaic cell equipment according to claim 1, characterized in that: The step of engraving a predetermined calibration pattern on the calibration piece after loading the target file includes: The laser system loads the target file to obtain predetermined monomask parameters, and controls the laser to continuously engrave on the calibration piece according to the monomask parameters to obtain N parallel calibration lines; The laser motion axis position and the laser motion axis angle corresponding to each of the N calibration lines are recorded.

3. The laser vision calibration method for photovoltaic cell equipment according to claim 1, characterized in that: The step of collecting a grayscale image of the calibration line in the detection area by an industrial camera and locating the position of the calibration line after performing image processing on the grayscale image comprises: Acquire grayscale images of the calibration line in the detection area by using multiple industrial cameras, wherein two cameras among the multiple industrial cameras are correspondingly set at two ends of the calibration line in one detection area; Performing distortion correction processing on the multiple cameras and calibrating the calibration plate, and converting the camera image coordinate systems corresponding to the multiple cameras into the same calibration plate coordinate system; After performing image processing on the grayscale image, the centerline position of each calibration line is located, and the centerline position of the calibration line is determined as the calibration line position.

4. The laser vision calibration method for photovoltaic cell equipment according to claim 3, characterized in that: The image processing of the grayscale image includes performing threshold processing on the grayscale image using the Sauvola local binarization algorithm. The Sauvola binarization formula is: Wherein, g(i,j) is the grayscale value at the pixel point (x,y) in the grayscale image, r is the neighborhood radius, m(x,y) is the pixel grayscale mean with r as the radius, s(x,y) is the grayscale variance of the neighborhood of the pixel point, k is the coefficient, R is the dynamic range of the standard deviation, and T(x,y) is the binarization threshold of the pixel point (x,y).

5. The laser vision calibration method for photovoltaic cell equipment according to claim 1, characterized in that: The step of fitting and calibrating the calibration line positions in each detection area on the calibration component and the actual positions of the calibration lines to obtain calibration results includes: Determine the perpendicular bisector of each calibration line at each laser motion axis angle to obtain a series of perpendicular bisectors; Extending the series of perpendicular bisectors, and determining the intersection point obtained by fitting the extended lines as the laser rotation center point; The position coordinates of the laser rotation center point are calculated using the least squares fitting method to obtain the anchor point position.

6. The laser vision calibration method for photovoltaic cell equipment according to claim 5, characterized in that: After determining the perpendicular bisector of each calibration line at each laser motion axis angle to obtain a series of perpendicular bisectors, the method further includes: Calculate the average value of a series of perpendicular bisectors under the current laser motion axis angle. The calculation formula is: in, is the average value of all bisector slopes at the current laser motion axis angle, is the mean of all perpendicular bisector intercepts at the current laser motion axis angle; By setting different calibration laser motion axis angle values, the average value of the perpendicular bisector corresponding to the calibration line at each laser motion axis angle is calculated. and The perpendicular bisectors under all laser motion axis angles are extended to fit a common intersection point, and the position coordinates of the laser rotation center are calculated using the least squares fitting method to obtain the anchor point position (x c ,y c ), the position coordinate formula of the laser rotation center point is determined as follows: Where n is the nth laser motion axis angle.

7. The laser vision calibration method for photovoltaic cell equipment according to claim 5, characterized in that: After calculating the position coordinates of the laser rotation center point using the least squares fitting method to obtain the anchor point position, the method further includes: Calculate the vertical distance from the anchor point to each calibration line position, perform linear fitting on the vertical distance and the laser motion axis coordinate value corresponding to the calibration line position, and obtain a first fitting relationship. The calculation formula is: y m =k m x m +b m Among them, x m is the distance from the anchor point to the calibration line, y m is the laser motion axis position (coordinate value) corresponding to the calibration line, k m and b m is the fitting parameter; The least square method is used to linearly fit each laser motion axis angle with the laser angle value in the calibration coordinate system after the grayscale image is calibrated to obtain the second fitting relationship. The calculation formula is: T=K×Ang+B Where K and B are fitting coefficients, and Ang is the corresponding laser angle value under the laser motion axis angle T.

8. The laser vision calibration method for photovoltaic cell equipment according to claim 7, characterized in that: After performing linear fitting on each laser angle and the laser angle value in the calibration coordinate system after calibration of the grayscale image using the least squares method to obtain a second fitting relationship, the method further includes: determining a target position of a laser motion axis in a production device during photovoltaic cell production based on a first fitting parameter in the first fitting relationship; Based on the second fitting parameter in the second fitting relationship, a laser angle value of a target processing line at a current laser motion axis angle during photovoltaic cell production is determined.

9. The laser vision calibration method for photovoltaic cell equipment according to claim 8, characterized in that: The method of determining the target position of the laser motion axis in the production equipment during photovoltaic cell production based on the first fitting parameter in the first fitting relationship includes calculating the laser rotation center point (x c ,y c ) to the distance X from the line to be processed j , according to the fitting parameter k m 、b m Calculate the actual target position Y of the laser motion axis j , the calculation formula is, Y j =k m X j +b m Among them, Y j is the laser axis motion position corresponding to the line to be processed; The determining of the laser angle value of the target processing line at the current laser motion axis angle during photovoltaic cell production based on the second fitting parameter in the second fitting relationship includes locating the angle value Ang of the line to be processed in each area during photovoltaic cell equipment production. j , calculate the laser angle value T of the processing line at the current laser motion axis angle based on the fitting parameters K and B j , the calculation formula is, T j =K×Ang j +B Among them, T j The current laser motion axis angle value.

10. A laser vision calibration device for photovoltaic cell equipment, characterized in that: include: An engraving unit is configured to cause the laser system to engrave a predetermined calibration pattern on the calibration piece according to a loaded target file, wherein the target file includes path information for the laser board to control the laser to engrave on the calibration piece; the calibration pattern includes parallel calibration lines; A positioning unit, configured to capture a grayscale image of the calibration line in the detection area through an industrial camera, and locate the position of the calibration line after performing image processing on the grayscale image; a calibration unit, configured to perform fitting calibration on the calibration line positions in each detection area on the calibration member and the actual positions of the calibration lines to obtain a calibration result; The first determination unit is configured to verify the calibration result and determine the angle value of the laser motion axis and the target position of the laser motion axis during photovoltaic cell production based on the calibration result.

Images