WO2020215703A1

WO2020215703A1 - Dynamic measurement system and method for flatness of cathode plate

Info

Publication number: WO2020215703A1
Application number: PCT/CN2019/118658
Authority: WO
Inventors: 吴俊义; 顾献代; 龚力; 张驰
Original assignee: 三门三友科技股份有限公司
Priority date: 2019-04-25
Filing date: 2019-11-15
Publication date: 2020-10-29
Also published as: ZA202104009B; CN110207625A; CN110207625B; WO2020215616A1

Abstract

A dynamic measurement system and method for flatness of a cathode plate. The measurement system mainly comprises a laser generator (1), a measurement surface (2), a front camera (3), and a side camera (4); the laser generator (1) is provided at a position directly facing the position directly below the intersection point of the diagonal lines of the measurement surface (2), and is used for projecting a set of n*n dot matrix onto the measurement surface (2); the front camera (3) is fixed directly above the laser generator (1); the laser generator (1) and the front camera (3) are both fixed on a fixed rod A(6); the side camera (4) is fixed on a fixed rod B(7); the front camera (3) and the side camera (4) upload collected image information to an industrial control computer (5) by means of a data transmission channel (8). The measurement system solves the problem of detecting a shaking process when a cathode plate product runs at a high speed, detected point positions are distributed more densely, and a detection result is more accurate; the present invention can collect statistics on the performance condition of the product in real time and view the performance condition.

Description

System and method for dynamically detecting flatness of cathode plate

Technical field

The invention relates to the field of cathode plate flatness detection technology, in particular to a dynamic detection system and method for cathode plate flatness.

Background technique

Existing stainless steel cathode plate flatness detection mainly adopts nine-point detection, using ranging sensors, 9 ranging sensors are installed at a certain distance on the surface of the product to be tested, and the flatness of the nine sensors is calculated and analyzed after obtaining the data. The testing equipment is installed in the assembly line equipment, and the product to be tested will shake when the assembly line is running. The faster the running speed, the greater the shaking amplitude. This equipment can adapt to the low-speed operation, but the detection result and the actual deviation at high-speed operation are larger. And with the increase of the product's use time, the deformation situation becomes more complicated, and the 9-point detection conditions can no longer ensure the detection accuracy. Therefore, it is necessary to develop a dynamic detection system and method for the flatness of the cathode plate to accurately detect the product under test in high-speed operation.

technical problem

The purpose of the present invention is to overcome the shortcomings of the prior art and provide a system and method for dynamically detecting the flatness of the cathode plate.

Technical solutions

The purpose of the present invention is accomplished through the following technical solutions: this kind of cathode plate flatness dynamic detection system and method mainly includes a laser generator, a detection surface, a front camera, and a side camera, which detects the front face directly below the intersection of the diagonals. A laser generator is set at the opposite position to project a group of n*n dot matrix on the detection surface. The front camera is fixed directly above the laser generator, and both the laser generator and the front camera are fixed on the fixed rod A. The side camera is fixed on the fixed rod B, and the front camera and the side camera upload the collected image information to the industrial computer through the data transmission channel.

Furthermore, the laser generator is arranged at a position 60 mm directly below the intersection of the detection faces.

Furthermore, a front camera is installed on the plane where the axially symmetric center line of the vertical direction of the laser projection of the laser generator and the center of the laser generator light source are located, and the angle is 45° with the laser generator; in the horizontal direction of the laser projection of the laser generator The side camera is installed on the plane where the axisymmetric center line of the laser generator and the center of the laser generator light source are located, and forms an angle of 45° with the laser generator.

The method for dynamically detecting the flatness of the cathode plate using the above-mentioned dynamic detecting system for the cathode plate flatness includes the following steps:

1) Install the laser generator: use a laser generator to project a group of n*n (n≥3) dot matrix on the detection surface, and the laser generator is set at the angle of 60mm directly below the intersection of the detection faces. At the location, installation distance

, Where α is the laser scattering angle, w is the deposition width, k is one-half of the minimum allowable distance of the image processing software and k≤h/2n, n is the number of laser lines, and h is the height of the surface to be inspected ；

2) Install the camera: install the camera and the detection surface at 15°≤γ≤75°, calculate the allowable swing angle of the surface to be tested

3). Collect and process photos: include the following steps:

A. The camera uploads the collected photos to the industrial computer, and the image processing software frame selects the first and last points of each group of lines as reference points;

B. The two points at the end of each group are connected to determine the baseline;

C. Select all projection points except for the reference point. Each line segment has 11 points, the first and last two points are reference points, and the remaining 9 points are reference points;

D. The reference point is perpendicular to the baseline;

E. Record and output the pixel value of each vertical line and its corresponding position;

4) Data processing: The industrial computer accepts the data output by the image processing software and processes it (executed by the C# program). Set the focal point of the camera as the origin O, the basic zero plane as XY, point A as the projection point on the zero plane, and C The point is the actual projection point with the deformed deviating surface; passing point C is the vertical line of OA, the vertical foot is B, and the vertical foot is the vertical line of the absolute zero plane, the vertical foot is E, and CE is the actual deviation value; let BC The pixel value of is x, the scale is k, the actual deviation of CE is

5) Actual calibration: includes the following steps:

A. Select the same board to be tested, test and record its pixel value multiple times;

B. Install a 1mm thick standard block on the surface of each point (excluding the reference point), and detect and record its pixel value multiple times;

C. Repeat the operation B 30 times (the deviation from normal will not exceed 30mm), adding a standard block each time;

D. Trace points on the coordinate system and draw the change curve. It is found that all are linear functions passing through the origin, and the slope is the K value;

E. Replace the board to be tested and iteratively optimize until the system error is within 3mm;

6) Output result: output the maximum value and its coordinates of each group, all the maximum value and its coordinates.

Beneficial effect

The beneficial effects of the present invention are:

1. Solve the problem of swaying process detection when the product is running at high speed;

2. The detection points are more densely distributed, and the detection results are more accurate;

3. The performance status of the product can be counted according to the test results in real time and viewed online.

Description of the drawings

Figure 1 is a schematic diagram of the structure of the present invention.

Figure 2 is a schematic diagram of the board surface to be tested and the laser dot matrix on the board surface.

Figure 3 is a schematic diagram of the installation position of the front camera.

Figure 4 is a schematic diagram of the side camera installation position.

Figure 5 is a schematic diagram of the laser spot zoomed in and pushed to the theoretical formula.

Figure 6 is a schematic diagram of the detection principle of the present invention.

Figure 7 is a schematic diagram of the detection process of the present invention.

Description of reference signs: laser generator 1, detection surface 2, front camera 3, side camera 4, industrial computer 5, fixed rod A6, fixed rod B7, and data transmission channel 8.

The best mode of the invention

Example: As shown in the figure, this kind of cathode plate flatness dynamic detection system includes a laser generator 1, a detection surface 2, a front camera 3, a side camera 4, and the detection surface 2 is located directly below the intersection of the diagonals There is a laser generator 1 at the place where it is used to project a group of n*n dot matrix on the detection surface 2. The front camera 3 is fixed directly above the laser generator 1, and both the laser generator 1 and the front camera 3 are fixed on the fixed On the rod A6, the side camera 4 is fixed on the fixed rod B7, and the front camera 3 and the side camera 4 upload the collected image information to the industrial computer 5 through the data transmission channel 8.

Preferably, the laser generator 1 is arranged at a position 60 mm directly below the intersection of the diagonals of the detection surface 2.

Preferably, the front camera 3 is installed on the plane where the axially symmetric center line of the vertical direction of the laser projection of the laser generator 1 and the light source center of the laser generator 1 are located, and the front camera 3 is at an angle of 45° with the laser generator 1; 1. Install the side camera 4 on the plane where the axisymmetric center line of the horizontal direction of the laser projection and the center of the laser generator 1 light source is located, and form an angle of 45° with the laser generator 1 to ensure that the image can cover the entire product.

1) Install the laser generator: use a laser generator 1 to project a group of n*n (n≥3) lattices on the detection surface 2 (as shown in Figure 2), and the laser generator 1 is set on the detection surface. The installation distance is 60mm directly below the intersection of the diagonals of face 2

2) Install the camera: the camera comes with a filter function, which only allows the light source corresponding to the light band to pass. The camera and the detection surface are installed at 15°≤γ≤75°, and the allowable swing angle of the surface to be tested is calculated

3). Collect and process photos: include the following steps:

A. The camera uploads the captured photos to the industrial computer 5. The image processing software frame selects the first and last points of each group of lines as the reference point. The frame selection principle: the photo has a high gray value after being filtered. The area can only be the projection point (the gray value of the projection of light in the unallowed band is 0), the software will automatically depict the area, and automatically find the center position of the area as the coordinates of the point (the same below);

D. The reference point is perpendicular to the baseline;

4) Data processing: The industrial computer 5 accepts the data output by the image processing software and processes it (executed by the C# program). Considering the angle between the camera and the plane where the laser point is located, the pixel value of each position is determined by the actual distance value. The corresponding coefficients are not the same. Let the focal point of the camera be the origin O (as shown in Figure 5), the basic zero plane is XY, point A is the projection point on the zero plane, and point C is the actual projection point with the deformed deviating surface; Cross point C is the vertical line of OA, the vertical foot is B, the vertical foot is the vertical line of the absolute zero plane, the vertical foot is E, CE is the actual deviation value; set the pixel value of BC as x and the scale as k, then The actual deviation of CE is

5) Actual calibration: includes the following steps:

6) Output result: output the maximum value of each group and its coordinates, all the maximum value and its coordinates, the output result has positive and negative points, indicating the deviation direction, and save the data in excel form.

Embodiments of the invention

This dynamic detection system for flatness of the cathode plate mainly includes a laser generator 1, a detection surface 2, a front camera 3, and a side camera 4. The detection surface 2 is provided with a laser generator 1 directly below the diagonal intersection point. Used to project a set of n*n dot matrix on the detection surface 2, the front camera 3 is fixed directly above the laser generator 1, the laser generator 1 and the front camera 3 are both fixed on the fixed rod A6, and the side camera 4 is fixed On the fixed rod B7, the front camera 3 and the side camera 4 upload the collected image information to the industrial computer 5 through the data transmission channel 8.

Industrial applicability

Detection principle: The laser line is projected on the stainless steel plate. Regardless of whether the plate is concave or convex, the laser imaging on the camera’s viewing angle will have a △H difference in the height direction (as shown in Figure 6). According to this difference The value software calculates the pixel value of this difference in the picture, and the detection flow chart is shown in Figure 7.

Claims

A dynamic detection system for the flatness of a cathode plate, which is characterized in that it mainly includes a laser generator (1), a detection surface (2), a front camera (3), a side camera (4), and a diagonal intersection point of the detection surface (2) A laser generator (1) is set directly below, which is used to project a group of n*n dot matrix on the detection surface (2). The front camera (3) is fixed on the laser generator (1). Above, the laser generator (1) and the front camera (3) are fixed on the fixed rod A (6), the side camera (4) is fixed on the fixed rod B (7), the front camera (3) and the side camera (4) ) Upload the collected image information to the industrial computer (5) through the data transmission channel (8).
The cathode plate flatness dynamic detection system according to claim 1, wherein the laser generator (1) is arranged at a position 60 mm directly below the intersection of the diagonals of the detection surface (2).
The cathode plate flatness dynamic detection system according to claim 1, characterized in that: the plane where the axially symmetric center line of the laser projection vertical direction of the laser generator (1) and the light source center of the laser generator (1) is located Install the front camera (3) and make an angle of 45° with the laser generator (1); install the side surface on the plane where the axially symmetric center line of the laser projector (1) horizontal direction and the laser generator (1) light source center are located The camera (4) forms an angle of 45° with the laser generator (1).
A detection method using the cathode plate flatness dynamic detection system according to claim 1, characterized in that it comprises the following steps:

1) Install the laser generator: use a laser generator (1) to project a group of n*n (n≥3) lattices on the detection surface (2), and the laser generator (1) is set on the detection surface (2) The installation distance is 60mm directly below the intersection of the diagonals
, Where α is the laser scattering angle, w is the deposition width, k is one-half of the minimum allowable distance of the image processing software and k≤h/2n, n is the number of laser lines, and h is the height of the surface to be inspected ；

2) Install the camera: the camera and the detection surface (2) are installed at 15°≤γ≤75°, and the allowable swing angle of the surface to be tested is calculated

3). Collect and process photos: include the following steps:

A. The camera uploads the collected photos to the industrial computer (5), and the image processing software frame selects the first and last points of each group of lines as reference points;

B. The two points at the end of each group are connected to determine the baseline;

C. Select all projection points except for the reference point. Each line segment has 11 points, the first and last two points are reference points, and the remaining 9 points are reference points;

D. The reference point is perpendicular to the baseline;

E. Record and output the pixel value of each vertical line and its corresponding position;

4) Data processing: Industrial computer (5) accepts and processes the data output by the image processing software. Set the focal point of the camera to the origin O, the basic zero plane to XY, point A to the projection point on the zero plane, and point C to have The actual projection point of the deformed deviating surface; passing point C is the vertical line of OA, the vertical foot is B, passing point C is the vertical line of the absolute zero plane, the vertical foot is E, CE is the actual deviation value; set the pixel value of BC Is x and the scale is k, the actual deviation of CE is

5) Actual calibration: includes the following steps:

A. Select the same board to be tested, test and record its pixel value multiple times;

B. Install a 1mm thick standard block on the surface of each point (excluding the reference point), and detect and record its pixel value multiple times;

C. Repeat operation B 30 times, adding a standard block each time;

D. Trace points on the coordinate system and draw the change curve. It is found that all are linear functions passing through the origin, and the slope is the K value;

E. Replace the board to be tested and iteratively optimize until the system error is within 3mm;

6) Output result: output the maximum value and its coordinates of each group, all the maximum value and its coordinates.

To