A copper strip spacing measurement method for a copper strip spiral winding type welding post

Abstract

The application discloses a copper strip interval measurement method for copper strip spiral winding type welding posts, and belongs to the technical field of industrial measurement, which comprises the following steps: using an optical sensor to acquire a welding post image; using an image enhancement processing method to enhance the welding post image; using a copper strip feature detection model to detect a rectangular frame corresponding to a copper strip position; performing linear fitting according to the rectangular frame coordinates of the copper strip position to obtain a mathematical equation approximate expression of a copper strip contour line; obtaining the intersection of a welding post vertical central axis and the copper strip contour line according to the mathematical equation approximate expression of the copper strip contour line; obtaining an initial measurement value of the copper strip interval by calculating the distance between adjacent intersection points; and obtaining a final measurement value of the copper strip interval by correcting the initial measurement value of the copper strip interval. The application can realize automatic detection of the copper strip interval of the copper strip spiral winding type welding post, and improve the accuracy and efficiency of detection.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of industrial measurement, and in particular to a copper strip spacing measurement method for a copper strip spiral winding type solder post. BACKGROUND

[0002] The solder post of the ceramic column grid array (CCGA) replaces the solder ball of the ceramic ball grid array (CBGA), and the solder post has stronger fatigue resistance, and the transmission quality and efficiency of signals are greatly improved. The CCGA package is often used in the field of aerospace electronic product manufacturing due to its special packaging form and strong adaptability to harsh environments.

[0003] The CCGA solder post mainly has two forms: one is a cast type solder post, and the main component is a 90Pb / 10Sn solder post; the other is a copper strip spiral winding type solder post, and the main component is 80Pb / 20Sn, and the surface is spirally wound by a copper strip. Compared with the cast type solder post, the copper strip spiral winding type solder post has better heat shock resistance and higher assembly reliability due to the stronger heat conduction performance of copper.

[0004] After the copper strip spiral winding type solder post is produced, the spacing parameter of the copper strip needs to be detected. In the traditional detection method, workers mainly use optical equipment such as a three-dimensional measuring instrument to manually measure the copper strip spacing parameter of each solder post, and the detection result of this method is greatly affected by the individual subjective influence, and the detection efficiency is low. Therefore, it is urgent to use an automatic detection method to improve the detection efficiency and accuracy. SUMMARY

[0005] The technical problem to be solved by the present application is how to improve the efficiency and accuracy of detecting the copper strip spacing of the copper strip spiral winding type solder post, and a copper strip spacing measurement method for a copper strip spiral winding type solder post is provided.

[0006] The present application solves the above technical problems by the following technical solutions, and the present application comprises the following steps:

[0007] S1: acquiring an initial image of the solder post by an optical sensor;

[0008] S2: using an image enhancement method to perform image enhancement on the initial image of the solder post to obtain an enhanced image of the solder post;

[0009] S3: using a copper strip feature detection model to process the enhanced image of the solder post to detect a rectangular frame corresponding to the copper strip feature position;

[0010] S4: performing linear fitting according to the coordinates of the copper strip feature position rectangular frame to obtain a mathematical equation approximate expression of the copper strip contour line;

[0011] S5: Obtain the mathematical equation expression of the vertical center axis of the soldering column, and combine the approximate expression of the mathematical equation of the copper strip contour line to obtain the intersection point of the vertical center axis of the soldering column and the copper strip contour line;

[0012] S6: Obtain the initial measurement value of the copper strip interval by calculating the distance between the adjacent intersection points capable of representing the copper strip interval in step S5;

[0013] S7: Obtain the final measurement value of the copper strip interval by correcting the initial measurement value of the copper strip interval.

[0014] Further, in the step S2, the image enhancement method includes image rotation, pixel value linear transformation, pixel value nonlinear transformation, image sharpening, and image detail enhancement method.

[0015] Further, in the step S3, the copper strip feature detection model is a target detection network based on deep learning. In order to enable the network to correctly detect the copper strip feature position, the network needs to be pre-trained. The training process includes the following steps:

[0016] S31: Collect a preset number of soldering column initial images through an optical sensor;

[0017] S32: Use an image enhancement method to enhance the soldering column initial image to obtain an enhanced image of the soldering column;

[0018] S33: For each enhanced image of the soldering column, use an artificial marking method to mark a rectangular frame corresponding to the copper strip feature position to form a label file;

[0019] S34: Divide the enhanced image of the soldering column and the label file into three parts: training set, validation set, and test set;

[0020] S35: Use the training set, validation set, and test set to train the target detection network so that it can correctly detect the rectangular frame corresponding to the copper strip feature position, and then obtain the copper strip feature detection model.

[0021] Further, in the step S3, the rectangular frame corresponding to the copper strip feature position, i.e. the copper strip feature position detection frame, is divided into left set LBoxes and right set RBoxes according to the left and right positions in the image; in each set, the rectangular frames are stored in order according to the upper and lower positions in the image, i.e.:

[0022] LBoxes={LB1, LB2, LB3, …}, LB i represents each left rectangular frame, i=1, 2, 3…

[0023] RBoxes={RB1, RB2, RB3, …}, RBi representing each right rectangular frame, i = 1, 2, 3…

[0024] Each rectangular frame includes four vertices, in order, the upper left, upper right, lower right, lower left vertices; each vertex coordinates include horizontal, vertical coordinates x, y two values, that is, each rectangular frame is represented as:

[0025] LB i = {(x L,i,TL ,y L,i,TL ), (x L,i,TR ,y L,i,TR ), (x L,i,BR ,y L,i,BR ), (x L,i,BL ,y L,i,BL )}, i = 1, 2, 3…

[0026] RB i = {(x R,i,TL ,y R,i,TL ), (x R,i,TR ,y R,i,TR ), (x R,i,BR ,y R,i,BR ), (x R,i,BL ,y R,i,BL )}, i = 1, 2, 3…

[0027] Wherein, the subscript L represents the left rectangular frame, the subscript R represents the right rectangular frame, the subscript TL represents the upper left vertex, the subscript TR represents the upper right vertex, the subscript BR represents the lower right vertex, and the subscript BL represents the lower left vertex.

[0028] Further, in the step S4, the copper strip profile line is divided into upper copper strip profile line L u and lower copper strip profile line L d , and the calculation steps of the mathematical equation approximate expression are:

[0029] S41: for the i pair of left and right rectangular frames, using the TL vertex (x L,i,TL ,y L,i,TL ) of the left rectangular frame and the TR vertex (x R,i,TR ,y R,i,TR ) of the right rectangular frame, the straight line equation is obtained as the mathematical equation approximate expression L ui of the i upper copper strip profile line; using the BL vertex (x L,i,BL ,y L,i,BL ) of the left rectangular frame and the BR vertex (x R,i,BR ,y R,i,BR ) of the right rectangular frame, the straight line equation is obtained as the mathematical equation approximate expression L di of the i lower copper strip profile line;

[0030] S42: Using all the left and right rectangle pairs, calculate the approximate mathematical equations for all copper strip outlines, and store them sequentially to obtain the following set:

[0031] Lines = {L u1 L d1 L u2 L d2 L u3 L d3 , ...}

[0032] Among them, L ui L represents the approximate mathematical equation for the i-th upper copper strip profile. di The mathematical equation approximates the expression for the i-th lower copper strip profile.

[0033] Furthermore, step S5 specifically includes the following steps:

[0034] S51: The location region of the weld post is determined by image contour detection. It is a rectangular bounding box with four vertices, and the expression is:

[0035] Hbox = {(x TL ,y TL ),(x TR ,y TR ),(x BR ,y BR ),(x BL ,y BL )};

[0036] S52: Based on the coordinates of the rectangular area where the welded column is located, obtain the mathematical equation for the vertical centerline of the welded column, as follows:

[0037] Lzz:x=0.5*(x TL +x TR );

[0038] S53: Determine the vertical centerline L of the welded column zz The intersection points with all copper strip outlines are used to obtain the set of intersection points:

[0039] Points = {Pu1, P} d1 P u2 P d2 P u3 P d3 , ...}

[0040] Among them, P ui P represents the intersection of the i-th upper copper strip outline and the vertical centerline. diThis represents the intersection of the i-th lower copper strip outline and the vertical centerline.

[0041] Furthermore, in step S6, the specific processing procedure is as follows: For the intersection point set Points, the distance between the intersection point of the i-th lower copper strip outline and the vertical centerline and the intersection point of the (i+1)-th upper copper strip outline and the vertical centerline is calculated and used as the initial measurement value D of the i-th copper strip spacing. i :

[0042] D i =Dis(P di ,P uj ), i = 1, 2, 3, ..., j = i + 1

[0043] Where Dis is the distance formula function between two points.

[0044] Furthermore, P di P uj Written in coordinate form, i.e., P di =(x di y di ), P uj =(x uj y uj Then we get:

[0045]

[0046] Furthermore, in step S7, the initial measurement value D of the copper strip spacing is used... i After correction, the final measured value DF of the copper strip spacing is obtained. i :

[0047] DF i =F(D) i ), i = 1, 2, 3, ...

[0048] Here, F is the correction function, and the coefficients of each term of the correction function F are obtained through pre-calibration.

[0049] Furthermore, the calibration process for the correction function F is as follows:

[0050] S71: Acquires a preset number of initial images of weld columns using an optical sensor;

[0051] S72: Use image enhancement methods to enhance the initial image of the weld column to obtain an enhanced image of the weld column;

[0052] S73: For each reinforced image of a weld pillar, the spacing between each copper strip is measured manually. i The set i = 1, 2, 3, ... is used as the actual value;

[0053] S74: using the method of steps S3-S6, the initial measurement set of copper strip spacing {D i , i = 1, 2, 3, …} is calculated.

[0054] S75: using the method of polynomial fitting, the set {D i} is fitted as {D i} to obtain the correction function F.

[0055] The copper strip spiral winding type soldering post copper strip spacing measurement method has the following advantages compared with the prior art: after obtaining the copper strip feature detection model and the correction function, the measurement of the copper strip spacing can be automatically completed, the influence of personal subjective factors during manual measurement is eliminated, and the detection efficiency and accuracy are improved. BRIEF DESCRIPTION OF DRAWINGS

[0056] Figure 1 is a measurement parameter diagram in the embodiment of the present application;

[0057] Figure 2 is a measurement flow diagram of the copper strip spiral winding type soldering post copper strip spacing measurement method in the embodiment of the present application. DETAILED DESCRIPTION

[0058] The embodiment of the present application will be described in detail below. The embodiment is implemented on the premise of the technical solution of the present application, and a detailed implementation manner and specific operation process are given. However, the protection scope of the present application is not limited to the following embodiment.

[0059] As shown in Figure 1 , it is a schematic diagram of related measurement parameters and also the detection idea of the present application. In the figure, 1 represents a copper strip spiral winding type soldering post, 2 represents a copper strip feature position rectangular frame (right), 3 represents a copper strip feature position rectangular frame (left), 4 represents a copper strip contour line (lower), 5 represents a copper strip contour line (upper), 6 represents a soldering post contour rectangular frame, 7 represents a soldering post vertical central axis, 8 represents the intersection of the copper strip contour line (lower) and the soldering post vertical central axis, 9 represents the intersection of the copper strip contour line (upper) and the soldering post vertical central axis, and 10 represents the copper strip spacing to be detected by the present application.

[0060] To detect the copper strip spacing, the traditional method is to use optical equipment such as a three-dimensional measuring instrument to manually measure. This method has low detection efficiency and the detection accuracy is easily affected by personal subjective factors.

[0061] To solve this problem, the copper strip spiral winding type soldering post copper strip spacing measurement method is provided in the embodiment. As can be seen from Figure 1 , the copper strip spacing is the distance between the intersection of the copper strip contour line and the vertical central axis, and the difficulty is how to detect the copper strip contour line. From Figure 1As can be seen, the copper band contour line is a curve and difficult to directly identify; at the same time, it is noticed that the copper band part of the left and right side walls of the stud (hereinafter referred to as "copper band feature position") has a significant difference in brightness from the surrounding. Therefore, by using a target detection network, the rectangular frame corresponding to the copper band feature position is first identified, and the relevant vertices of the left and right rectangular frames are connected, so that the approximate expression of the mathematical equation of the copper band contour line can be obtained; then by using a digital image processing method, the contour rectangular frame of the entire stud can be easily obtained, and then the mathematical equation expression of the vertical central axis can be obtained; according to the mathematical equation expression, the intersection point of the copper band contour line and the vertical central axis can be obtained; by calculating the distance between the relevant intersection points, the initial measurement value of the copper band spacing can be obtained. In the process, because the approximation of the copper band contour line is used, the initial measurement value of the copper band spacing needs to be corrected to obtain the final measurement value of the copper band spacing.

[0062] As shown in FIG. 1, it is a flowchart of the copper band spacing measurement method of the copper band spiral winding type stud in the embodiment, which includes the following steps: Figure 2

[0063] Step 1: Obtain the initial image of the stud by using an optical sensor.

[0064] In this step, the imaging method of the stud can be, but is not limited to, ordinary light source imaging, infrared imaging, X-ray imaging, etc., and the imaging method that can best highlight the copper band feature area should be selected according to the actual environment scene.

[0065] Step 2: Use an image enhancement method to enhance the initial image of the stud to obtain an enhanced image of the stud, so as to highlight the copper band feature area.

[0066] In this step, the image enhancement method includes but is not limited to image rotation, pixel value linear transformation, pixel value nonlinear transformation, image sharpening, image detail enhancement, etc.

[0067] Step 3: Use a copper band feature detection model to process the enhanced image of the stud to detect the rectangular frame corresponding to the copper band feature position. These rectangular frames are divided into left set LBoxes and right set RBoxes according to the left and right positions in the image. In each set, the rectangular frames are stored in order according to the upper and lower positions in the image, i.e.:

[0068] LBoxes={LB1, LB2, LB3, …}, LB i represents each left rectangular frame, i=1, 2, 3…

[0069] RBoxes={RB1, RB2, RB3, …}, RB i represents each right rectangular frame, i=1, 2, 3…

[0070] ​And each rectangular frame is composed of four vertices, in order, top left (TL), top right (TR), bottom right (BR), bottom left (BL); each vertex is composed of two values of horizontal and vertical coordinates (x, y), that is, each rectangular frame can be represented as:

[0071] LB i = {(x L,i,TL ,y L,i,TL ), (x L,i,TR ,y L,i,TR ), (x L,i,BR ,y L,i,BR ), (x L,i,BL ,y L,i,BL )}, i = 1, 2, 3…

[0072] RB i = {(x R,i,TL ,y R,i,TL ), (x R,i,TR ,y R,i,TR ), (x R,i,BR ,y R,i,BR ), (x R,i,BL ,y R,i,BL )}, i = 1, 2, 3…

[0073] In the formula, subscript L represents the left rectangular frame, subscript R represents the right rectangular frame, subscript TL represents the top left vertex, subscript TR represents the top right vertex, subscript BR represents the bottom right vertex, and subscript BL represents the bottom left vertex.

[0074] In this step, the copper strip feature detection model is a target detection network based on deep learning, which can be but is not limited to R-CNN, Faster R-CNN, SSD, yolo, etc. In order to enable the target detection network to correctly detect the copper strip feature position, the network needs to be pre-trained, and the training includes the following steps: 1) collect a preset number of initial images of the soldering post through an optical sensor; 2) use image enhancement methods to enhance the soldering post initial image to highlight the copper strip feature area; 3) for each soldering post enhanced image, use an artificial marking method to mark the rectangular frame corresponding to the copper strip feature position to form a label file; 4) divide the above enhanced images and label files into three parts: training set, validation set, and test set; 5) use the above training set, validation set, and test set to train the target detection network so that it can correctly detect the rectangular frame corresponding to the copper strip feature position, and then obtain the copper strip feature detection model.

[0075] Step 4: According to the coordinates of the copper strip feature position rectangular frame, a straight line fitting is performed to obtain the approximate expression of the mathematical equation of the copper strip contour line, and the calculation method is as follows:

[0076] 1) For the i-th pair of left and right rectangles, use the TL vertex (x) of the left rectangle. L,i,TL ,y L,i,TL ) and the TR vertex (x) of the right rectangle R,i,TR ,y R,i,TR The equation of the straight line is obtained, which serves as an approximate expression L for the mathematical equation of the i-th upper copper strip contour line. ui Use the BL vertex (x) of the left rectangle. L,i,BL ,y L,i,BL ) and the BR vertex (x) of the right rectangle R,i,BR ,y R,i,BR The equation of the straight line is obtained, which serves as an approximate mathematical expression L for the i-th lower copper strip contour line. di ;

[0077] 2) Using all the left and right rectangle pairs, calculate the approximate mathematical equations for all copper strip outlines, and store them sequentially to obtain a set.

[0078] Lines = {L u1 L d1 L u2 L d2 L u3 L d3 , ...}

[0079] When calculating the outline of a copper strip using a rectangular frame representing its feature location, appropriate adjustments should be made based on the completeness of the frame. Figure 1 For example, Figure 1 The top right rectangle cannot represent the complete copper strip feature position, so only this rectangle is used to calculate the lower copper strip outline; similarly, Figure 1 The rectangle at the bottom left of the middle section cannot represent the complete copper strip feature position, so only this rectangle is used to calculate the copper strip outline.

[0080] Step 5: Obtain the mathematical equation for the vertical centerline of the welded column, and combine it with the approximate mathematical equation for the copper strip outline to find the intersection point of the vertical centerline of the welded column and the copper strip outline. Calculation method: 1) Using digital image processing methods, determine the location region of the welded column, which is a rectangular frame composed of four vertices. The expression is:

[0081] Hbox = {(x TL ,y TL ),(x TR ,y TR ),(x BR ,y BR ),(x BL ,y BL )}

[0082] 2) According to the rectangular frame coordinates of the area where the stud is located, the mathematical equation expression of the vertical central axis of the stud is obtained, which is:

[0083] Lzz: x = 0.5 * (x TL +x TR )

[0084] 3) The vertical central axis L zz of the stud is obtained by intersecting with all the copper belt contour lines Lines, and the intersection point set is obtained:

[0085] Points = {P u1 , P d1 , P u2 , P d2 , P u3 , P d3 , …}

[0086] In the formula, P ui represents the intersection point of the i-th upper copper belt contour line and the vertical central axis, and P di represents the intersection point of the i-th lower copper belt contour line and the vertical central axis.

[0087] Step 6: For the above intersection point set Points, the initial measurement value of the copper belt spacing is obtained by calculating the distance between adjacent intersection points. Specifically, the distance between the intersection point of the i-th lower copper belt contour line and the vertical central axis and the intersection point of the (i+1) -th upper copper belt contour line and the vertical central axis is calculated as the initial measurement value D i of the i-th copper belt spacing, that is:

[0088] D i = Dis(P di , P uj ), i = 1, 2, 3, …, j = i + 1

[0089] In the formula, Dis is the distance formula function between two points, which is used to calculate the distance between the two points according to the coordinates of the two intersection points.

[0090] In the distance formula function, assuming that the coordinates of the two points are (x1, y1) and (x2, y2), the distance between the two points is:

[0091]

[0092] In step 6, the intersection points in the initial measurement formula can be written in coordinate form, that is, P di is written as (x di , y di ), and P uj is written as (x uj , y uj ), then

[0093] Step 7: Through the initial measurement value D of the copper strip spacing i correction, the final measurement value DF of the copper strip spacing is obtained i .

[0094] DF i = F(D i ), i = 1, 2, 3, …

[0095] In the formula, F is a correction function, and the coefficients of each term of the function are obtained by pre-calibration. The calibration method is as follows: 1) Through the optical sensor, a preset number of initial images of the solder post are collected; 2) Using image enhancement method, the initial images of the solder post are enhanced to obtain the enhanced images of the solder post, so as to highlight the copper strip feature area; 3) For each enhanced image of the solder post, the manually measured method is used to measure each copper strip spacing {DT i , i = 1, 2, 3, …}, which is used as the true value; 4) Using the above method, the initial measurement value set {D i , i = 1, 2, 3, …} of the copper strip spacing is calculated; 5) Using the polynomial fitting method, the set {D i} is polynomial fitted according to {DT i}, and the correction function F is obtained.

[0096] In summary, the copper strip spacing measurement method of the copper strip spiral winding type solder post in the above embodiment can automatically complete the measurement of the copper strip spacing after obtaining the copper strip feature detection model and the correction function, eliminates the influence of personal subjective factors during manual measurement, and improves the detection efficiency and accuracy.

[0097] Although the embodiments of the present application have been shown and described above, it should be understood that the above embodiments are exemplary and should not be construed as limiting the present application, and those skilled in the art can make changes, modifications, replacements and variations to the above embodiments within the scope of the present application.

Claims

1. A method of measuring the pitch of copper straps of a copper strap spiral wound type lug, characterized by, The method comprises the following steps: S1: obtaining an initial image of the solder post by an optical sensor; S2: performing image enhancement on the initial image of the solder post by using an image enhancement method to obtain an enhanced image of the solder post; S3: processing the enhanced image of the solder post by using a copper strip feature detection model to detect a rectangular frame corresponding to the copper strip feature position; S4: performing straight line fitting according to the coordinates of the rectangular frame of the copper strip feature position to obtain a mathematical equation approximate expression of the copper strip contour line; S5: obtaining a mathematical equation expression of the vertical central axis of the solder post, and combining the mathematical equation approximate expression of the copper strip contour line to obtain the intersection of the vertical central axis of the solder post and the copper strip contour line; S6: obtaining an initial measurement value of the copper strip spacing by calculating the distance between the adjacent intersection points capable of representing the copper strip spacing in step S5; S7: obtaining a final measurement value of the copper strip spacing by correcting the initial measurement value of the copper strip spacing.

2. The copper ribbon spacing measurement method of a copper ribbon spiral-wound stud according to claim 1, characterized by: In the step S2, the image enhancement method comprises image rotation, pixel value linear transformation, pixel value nonlinear transformation, image sharpening and image detail enhancement method.

3. The copper ribbon spacing measurement method of a copper ribbon spiral-wound stud according to claim 1, characterized by: In the step S3, the copper strip feature detection model is a target detection network based on deep learning. In order to enable the network to correctly detect the copper strip feature position, the network needs to be pre-trained. The training process comprises the following steps: S31: collecting a preset number of initial images of the solder post by an optical sensor; S32: performing image enhancement on the initial image of the solder post by using an image enhancement method to obtain an enhanced image of the solder post; S33: marking the rectangular frame corresponding to the copper strip feature position by using an artificial marking method for each enhanced image of the solder post to form a label file; S34: dividing the enhanced image of the solder post and the label file into three parts of a training set, a validation set and a test set; S35: training the target detection network by using the training set, the validation set and the test set to enable the network to correctly detect the rectangular frame corresponding to the copper strip feature position, and thus obtaining the copper strip feature detection model.

4. The copper ribbon spacing measurement method of a copper ribbon spiral-wound stud according to claim 1, characterized by: In the step S3, the rectangular frame corresponding to the copper strip feature position, i.e. the copper strip feature position detection frame, is divided into a left set LBoxes and a right set RBoxes according to the left and right positions in the image. In each set, the rectangular frames are sequentially stored according to the upper and lower positions in the image, i.e. LBoxes = {LB1, LB2, LB3,...}, LB i represents each left rectangular box, i = 1, 2, 3... RBoxes = {RB1, RB2, RB3,...}, RB i Represent each right side rectangle box, i = 1, 2, 3... Each rectangular frame comprises four vertices, which are sequentially the left upper vertex, the right upper vertex, the right lower vertex and the left lower vertex. Each vertex coordinate comprises two values of horizontal coordinate x and vertical coordinate y, i.e. each rectangular frame is represented as: LB i = {(x L,i,TL ,y L,i,TL ),(x L,i,TR ,y L,i,TR ),(x L,i,BR ,y L,i,BR ),(x L,i,BL ,y L,i,BL )}, i = 1, 2, 3… RB i = {(x R,i,TL ,y R,i,TL ),(x R,i,TR ,y R,i,TR ),(x R,i,BR ,y R,i,BR ),(x R,i,BL ,y R,i,BL )}, i = 1, 2, 3… Wherein, the subscript L represents the left rectangular frame, the subscript R represents the right rectangular frame, the subscript TL represents the left upper vertex, the subscript TR represents the right upper vertex, the subscript BR represents the right lower vertex and the subscript BL represents the left lower vertex.

5. The method for measuring the copper strip spacing of a spiral-wound copper strip welding column according to claim 4, characterized in that: In the step S4, the copper strip profile line is divided into an upper copper strip profile line L u , a lower copper strip profile line L d The calculation step of the mathematical equation approximate expression is: S41: for the i-th pair of left and right rectangular frames, using the TL vertex (x L,i,TL ,y L,i,TL ) of the left rectangular frame and the TR vertex (x R,i,TR ,y R,i,TR ) of the right rectangular frame, a straight line equation is obtained as the mathematical equation approximate expression L ui of the i-th upper copper belt contour line. The BL vertex (x L,i,BL ,y L,i,BL ) of the left rectangular frame and the BR vertex (x R,i,BR ,y R,i,BR ) of the right rectangular frame are used to obtain a straight line equation as a mathematical equation approximate expression L di of the i-th lower copper belt contour line. S42: calculating the mathematical equation approximate expression of all the copper strip contour lines by using all the left and right rectangular frame pairs, and sequentially storing them to obtain the following set: Lines = {L u1 , L d1 , L u2 , L d2 , L u3 , L d3 ,...} where L ui represents a mathematical equation approximation expression of the profile line of the i-th upper copper tape di represents a mathematical equation approximation expression of the profile line of the i-th lower copper tape 6. The copper ribbon spacing measurement method of a copper ribbon spiral-wound stud according to claim 5, characterized by: In the step S5, the following steps are specifically included: S51: obtaining a position region of the solder post by using an image contour detection method, which is a rectangular frame comprising four vertices, and the expression is: Hbox = {(x TL ,y TL ),(x TR ,y TR ),(x BR ,y BR ),(x BL ,y BL )}; S52: According to the rectangular frame coordinates of the position area where the welding column is located, the mathematical equation expression of the vertical central axis of the welding column is obtained, as follows: Lzz: x = 0.5 * (x TL +x TR ); S53: Find the vertical center axis L of the soldering post zz Intersection with all copper band profile lines of Lines, resulting in a set of intersection points: Points = {P u1 , P d1 , P u2 , P d2 , P u3 , P d3 ,...} where P ui represents the intersection of the i-th upper copper strip profile line with the vertical center axis, P di represents the intersection of the i-th lower copper strip profile line with the vertical center axis.

7. The method for measuring the copper strip spacing of a spiral-wound copper strip welding column according to claim 6, characterized in that: In the step S6, the specific processing process is as follows: for the intersection set Points, by calculating the distance between the intersection point of the i th lower copper strip contour line and the vertical center axis and the intersection point of the (i+1) th upper copper strip contour line and the vertical center axis, as the initial measured value D of the i th copper strip spacing i : D i = Dis(P di ,P uj ), i = 1, 2, 3,..., j = i + 1 Wherein, Dis is the distance formula function between two points.

8. The method of claim 7, wherein the copper strip pitch of the copper strap spiral wound terminal is measured by: 1) cutting the copper strap spiral wound terminal at a predetermined location; 2) removing the copper strap from the copper strap spiral wound terminal; 3) measuring the length of the removed copper strap; and 4) calculating the copper strip pitch of the copper strap spiral wound terminal. P di , P uj are written in coordinate form, i.e. P di = (x di , y di ), P uj = (x uj , y uj ), then we obtain:

9. The method of claim 8, wherein the copper strip pitch of the copper strap spiral wound terminal is measured by: 1) cutting the copper strap spiral wound terminal at a predetermined location; 2) removing the copper strap from the copper strap spiral wound terminal; 3) measuring the length of the removed copper strap; and 4) calculating the copper strip pitch of the copper strap spiral wound terminal. In said step S7, the initial measurement value D of the copper band spacing is corrected by means of a correction value i resulting in a final measurement value DF of the copper band spacing i : DF i = F(D i ), i = 1, 2, 3,... Wherein, F is a correction function, and the coefficients of each term of the correction function F are obtained through pre-calibration.

10. The method of claim 9, wherein the copper strip pitch of the copper strap spiral wound terminal is measured by: 1) cutting the copper strap spiral wound terminal at a predetermined location; 2) removing the copper strap from the copper strap spiral wound terminal; 3) measuring the length of the removed copper strap; and 4) calculating the copper strip pitch of the copper strap spiral wound terminal. The calibration process of the correction function F is as follows: S71: Collect a preset number of initial images of the welding column through an optical sensor; S72: Use an image enhancement method to perform image enhancement on the initial images of the welding column to obtain enhanced images of the welding column; S73: For each enhanced image of the stud, using the manual measurement method, measure the distance between each copper band {DT i i = 1, 2, 3,...}, which is taken as the true value; S74: Using the manner of steps S3-S6, the initial measurement set of copper strip spacing {D i i = 1, 2, 3,...}; S75: Using the method of polynomial fitting, the set {D i} is fitted according to {DT i} to obtain the correction function F.

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