Multi-valve dispensing interpolation algorithm

Abstract

The present application aims to provide a multi-valve dispensing interpolation algorithm which can simultaneously dispense the same product at different angles and different relative positions, and can improve the dispensing motion accuracy and weight accuracy. The present application comprises the following steps: A. using a visual shooting device to calibrate the positions of several valve bodies and calculate the distance between each adjacent two valve bodies; B. using a visual shooting device to locate the positions of several products and calculate the position deviation MD and angle deviation RD of each product; C. taking the coordinates of the first valve body as the origin, and automatically assigning the products to be dispensed by the valve body according to the distance FD between the valve bodies; D. using a robot to control several valve bodies to dispense, and using a robot interpolation motion algorithm; E. using several valve bodies to dispense, and using a separate control channel for each valve body. The present application is applied to the field of product dispensing technology.

Description

Technical Field

[0001] The present invention is applied to the technical field of product dispensing, and particularly relates to a multi-valve dispensing interpolation algorithm. Background Art

[0002] At present, there are mainly the following types of dispensing interpolation algorithms: 1. Single-valve single-axis dispensing interpolation algorithm, which only controls one valve body to dispense one product at a time. Although the accuracy is high, the production efficiency is low; 2. Multi-valve single-axis dispensing interpolation algorithm, since it can only manually move the position of the auxiliary valve, it is essentially the same as the first method. It can only control multiple valve bodies to dispense multiple products with the same angle and the same spacing. It has high requirements for the placement angle and position accuracy of the products produced, and has low adaptability to the products in the production environment. It can only be used in some low-precision dispensing occasions; 3. Multi-valve multi-axis dispensing interpolation algorithm, since it only moves the valve body to the corresponding position before dispensing, and does not move the auxiliary valve during the dispensing process (the main valve and auxiliary valve remain in a fixed position), it can only achieve multiple valve bodies dispensing multiple products with the same angle and different spacing. It has high requirements for the placement angle accuracy of the products produced, and can only be applied to some regularly arranged products.

[0003] Existing multi-valve dispensing interpolation algorithms only achieve uniform glue volume control, meaning that the number of glue points dispensed from multiple valve bodies is consistent. However, due to inherent physical differences between valve bodies, and the varying viscosity of glue due to age, the glue dispensed from each valve body will vary slightly (single dispense volume N). This can lead to inconsistent dispensed volumes across multiple products when the number of dispense points (D) is the same for each valve. (For example, if N1 != N2, and the glue weight (W) on the product is W1 = N1*D and W2 = N2*D, it follows that W1 != W2.) Designing a multi-valve dispensing interpolation algorithm that can simultaneously dispense the same product at multiple angles and relative positions while simultaneously improving both dispensing motion accuracy and dispensed weight accuracy would effectively address these issues. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a multi-valve dispensing interpolation algorithm that can simultaneously dispense glue on the same product at multiple different angles and relative positions while simultaneously improving the dispensing motion accuracy and dispensing weight accuracy.

[0005] The technical solution adopted by the present invention is: the present invention comprises the following steps:

[0006] A. Use visual shooting equipment to calibrate the positions of several valve bodies and calculate the distance between each two adjacent valve bodies;

[0007] B. Use visual camera equipment to locate the positions of several products and calculate the position deviation MD and angle deviation RD of each product;

[0008] C. With the coordinates of the first valve body as the origin, the product dispensed by the valve body is automatically distributed based on the distance FD between the valve bodies;

[0009] D. When using a robot to control several valve bodies for dispensing, interpolate the motion algorithm of the robot;

[0010] E. When using several valve bodies for dispensing, each valve body uses a separate control channel.

[0011] Furthermore, the manipulator includes a main three-axis module and a secondary three-axis module, the secondary three-axis module is arranged on the main three-axis module, the movable end of the main three-axis module is provided with a first valve body, and the movable end of the secondary three-axis module is provided with a second valve body; the method for calculating the distance between each two adjacent valve bodies includes the following steps:

[0012] A1. Reset the main three-axis module and the secondary three-axis module;

[0013] A2. The coordinates of all axes of the main three-axis module and the secondary three-axis module are set to 0;

[0014] A3. Drive the main three-axis module to move the first valve body to the appropriate dispensing position;

[0015] A4. Control the first valve body to dispense glue and record the glue dispensing position at this time as F (X1, Y1, Z1);

[0016] A5. Drive the main three-axis module until the visual camera can see the glue dot on the first valve body. Align the center of the visual camera's field of view with the center of the glue dot, and record the camera's photographic coordinates as C (X2, Y2, Y2).

[0017] A6. Calculate the distance D1=FC between the center of the field of view and the center of the glue point;

[0018] A7. Similarly, the second valve body obtains the coordinate difference D2 between the center of the field of view and the center of the glue point according to steps A1-A6;

[0019] A8. After all valve positions are calibrated, calculate the distance between adjacent valves (FD = D1 - D2).

[0020] Furthermore, the method for calculating the position deviation MD and the angle deviation RD includes the following steps:

[0021] B1. Place a product in the field of view of the visual capture device;

[0022] B2. Find two reference points on the product, visually establish a template, after teaching, move the visual field center to the reference point center, and record the shooting positions as M1 and M2, the center of the product is M=(M1+M2) / 2;

[0023] B3. Teach the dispensing process, and the product cannot be moved during the entire process;

[0024] B4. Place the product for production, and the visual shooting device takes pictures when it runs to M1 and M2, at this time, the visual can obtain the offset values of the first reference point (Dx1, Dy1) and the offset values of the second reference point (Dx2, Dy2), and convert them into actual coordinates M1' and M2', and the center of the product is M'=(M1'+M2') / 2;

[0025] B5. Calculate the positional deviation of the product as MD=M-M';

[0026] B6. Calculate the angular deviation of the product, and the angle between the two line segments formed by M1, M2 and M1', M2' can be obtained.

[0027] Further, the motion algorithm comprises the following steps:

[0028] D1. Drive the secondary three-axis module, so that the distance between the first valve body and the second valve body is equal to the distance between the two products;

[0029] D2. Drive the Z-axis of the primary three-axis module and the secondary three-axis module, so that the first valve body and the second valve body move to the appropriate dispensing height;

[0030] D3. In the dispensing interpolation motion, one of the products is responsible for completing the motion by the primary three-axis module;

[0031] D4. The secondary three-axis module is responsible for compensating the motion of the primary three-axis module, so that the first valve body on the primary three-axis module dispenses one of the products, while the second valve body dispenses the other product;

[0032] D5. During the motion of the primary three-axis module, the secondary three-axis module also moves, and due to the characteristics of the interpolation motion, the axes will automatically distribute the speed, so that they can be started and stopped at the same time, so that when the first valve body dispenses, the second valve body compensates for the coordinate distance between dispensing points on the product, so that different angle and different position products can be dispensed at the same time.

[0033] The beneficial effects of the present invention are: 1. Compared with a single-valve single-axis system, the present invention enables simultaneous dispensing of multiple valve bodies, and the dispensing motion accuracy and dispensing weight accuracy are consistent with those of a single-valve single-axis system; 2. Compared with a multi-valve single-axis system and a multi-valve multi-axis system, the present invention enables simultaneous dispensing of products at multiple angles and different spacings, and the dispensing weight can be controlled individually. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a flow chart of the algorithm for calculating the distance between each valve body;

[0035] Figure 2 It is a schematic diagram of the reference center at the center of the camera field of view;

[0036] Figure 3 This is a schematic diagram obtained by taking pictures when the camera moves to M1 and M2;

[0037] Figure 4 It is a hypothetical schematic diagram of the product;

[0038] Figure 5 This is a schematic diagram of the second valve body dispensing glue within a rectangular range with the first valve body as the origin;

[0039] Figure 6 It is the first schematic diagram of the product within the rectangular range;

[0040] Figure 7 This is the second schematic diagram of the product within the rectangular range. DETAILED DESCRIPTION

[0041] In this embodiment, the present invention includes the following steps:

[0042] A. Use visual shooting equipment to calibrate the positions of several valve bodies and calculate the distance between each two adjacent valve bodies;

[0043] B. Use visual camera equipment to locate the positions of several products and calculate the position deviation MD and angle deviation RD of each product;

[0044] C. With the coordinates of the first valve body as the origin, the product dispensed by the valve body is automatically distributed based on the distance FD between the valve bodies;

[0045] D. When using a robot to control several valve bodies for dispensing, interpolate the motion algorithm of the robot;

[0046] E. When using several valve bodies for dispensing, each valve body uses a separate control channel.

[0047] In this embodiment, the visual shooting device is an industrial camera.

[0048] In this embodiment, the manipulator includes a main three-axis module and a secondary three-axis module, the secondary three-axis module is arranged on the main three-axis module, the movable end of the main three-axis module is provided with a first valve body, and the movable end of the secondary three-axis module is provided with a second valve body; Figure 1 As shown, the method for calculating the distance between each two adjacent valve bodies includes the following steps:

[0049] A1. Reset the main three-axis module and the secondary three-axis module;

[0050] A2. The coordinates of all axes of the main three-axis module and the secondary three-axis module are set to 0;

[0051] A3. Drive the main three-axis module to move the first valve body to the appropriate dispensing position;

[0052] A4. Control the first valve body to dispense glue and record the glue dispensing position at this time as F (X1, Y1, Z1);

[0053] A5. Drive the main three-axis module until the visual camera can see the glue dot on the first valve body. Align the center of the visual camera's field of view with the center of the glue dot, and record the camera's photographic coordinates as C (X2, Y2, Y2).

[0054] A6. Calculate the distance D1=FC between the center of the field of view and the center of the glue point;

[0055] A7. Similarly, the second valve body obtains the coordinate difference D2 between the center of the field of view and the center of the glue point according to steps A1-A6;

[0056] A8. After all valve positions are calibrated, calculate the distance between adjacent valves (FD = D1 - D2).

[0057] In this embodiment, the method for calculating the position deviation MD and the angle deviation RD includes the following steps:

[0058] B1. Place a product in the field of view of the visual capture device;

[0059] B2. Find two reference points on the product, create a visual template, and after teaching, move the visual field center to the center of the reference point (that is, when viewed from the industrial camera, the reference center is at the center of the camera field of view, such as Figure 2 As shown in the figure), record the photo positions as M1 and M2, and the center of the product as M=(M1+M2) / 2;

[0060] B3. Teach the dispensing process. The product cannot be moved during the whole process.

[0061] B4. Place the product for production and start production. The visual shooting device takes pictures when it runs to M1 and M2. The pictures obtained are as follows Figure 3 As shown, the visual sense can obtain the offset value of the first reference point as (Dx1, Dy1), and the offset value of the second reference point as (Dx2, Dy2). These values ​​are converted into actual coordinates M1' and M2', and the center of the product is M' = (M1'+M2') / 2.

[0062] B5. Calculate the product position deviation as MD = M-M';

[0063] B6. Calculate the angular deviation of the product. Given the two line segments formed by M1, M2 and M1', M2', find the angle between the line segments.

[0064] In this embodiment, after visually locating the angles and positions of multiple products, the coordinates of the first valve body are used as the origin, and the distance FD between the valve bodies is used to automatically allocate the products to be dispensed by the valve bodies (a double valve is used as an example below). From step A, it can be determined that the distance between the first valve body and the second valve body is FD (assuming it is (40, 0), that is, the difference in the X direction is 40mm, and the difference in the Y direction is 0), and the XY axis movable range of the secondary three-axis module is X3 (plus or minus 20mm) and Y3 (plus or minus 5mm). Therefore, the second valve body can dispense glue within a rectangular range with the first valve body as the origin, the upper left corner is (20, 5), and the lower right corner is (60, -5). Figure 5 shown.

[0065] In this embodiment, if Figure 4 As shown, the algorithm will screen products that meet the dispensing range of the first valve body and the second valve body from 1 to 14 in the programmed order. Assuming that the visual positioning shows that the spacing between product No. 1 and products No. 2, 3, 4, 5, 6, and 7 are P21 (10.3, 1.6), P31 (19.7, -2.1), P41 (31.3, 1.2), P41 (31.3, 1.2), P51 (43.3, -0.8), P61 (50.8, 0.3), and P71 (62.3, 1.3), it is obvious that products No. 4, 5, and 6 are all within the rectangular range with the first valve body as the origin and the upper left corner at (20, 5) and the lower right corner at (60, -5). Figure 6 As shown, the second layer algorithm is then entered.

[0066] In this embodiment, if Figure 7 As shown, next, A1, B1, C1, D1 and A4, B4, C4, D4 on products No. 1 and No. 4 are subtracted from each other to check whether they are within the rectangular range with the first valve body as the origin and the upper left corner at (20, 5) and the lower right corner at (60, -5).

[0067] In this embodiment, the algorithm selects the first two products calculated to match the region for pairing. Based on the program number, products 1 and 4 are paired first and eliminated from the pairing combination. Then, products 2 and 5 are paired, followed by products 3 and 6, with product 7 remaining (the algorithm automatically assigns the first valve body to separate dispensing to ensure even and odd numbers are compatible). The algorithm then proceeds to the second row, and so on. Flexible pairing can be achieved based on the hardware's axis range, or the range can be narrowed down to meet actual needs.

[0068] In this embodiment, taking product No. 1 and product No. 4 as examples, the motion algorithm includes the following steps:

[0069] D1. Drive the XY axes of the auxiliary three-axis module so that the distance between the first valve body and the second valve body is equal to the distance between A1 and A4. When the XY axes of the auxiliary three-axis module are at (0, 0), the distance between the first valve body and the second valve body is FD (40, 0); when the distance between the first valve body and the second valve body is A14 (24.14, -3.8), 24.14 -40 = -15.86 = x1, -3.8-0=-3.8, so the XY axis coordinates are PA14 (-15.86, -3.8); B14 (35.2, -2.7), C14 (36.1, 2), and D14 (25.46, 2.3) also give the XY axis coordinates PB14 (-4.8, -2.7), PC14 (-3.9, 2), and PD14 (-14.54, 2.3). Moving the XY axis to PA14 (-15.86, -3.8) will make the distance between the first and second valve bodies equal to the distance between A1 and A4.

[0070] D2 drives the Z axis of the main three-axis module and the secondary three-axis module to move the first valve body and the second valve body to the appropriate dispensing height;

[0071] D3. During interpolation dispensing, the main three-axis module is still responsible for completing the movement of product No. 1. That is, the main three-axis module will move and dispense glue along the coordinate path of A1, B1, C1, and D1;

[0072] D4. The secondary three-axis module is responsible for compensating for the movement of the main three-axis module, so that the first valve body on the main three-axis module dispenses glue on product No. 1, while the second valve body dispenses glue on product No. 4;

[0073] D5. As the main three-axis module moves from A1 to B1 on product No. 1, the secondary three-axis module moves from coordinates PA14 to PB14. Due to the characteristics of interpolation motion, the speeds of the axes are automatically distributed, allowing them to start and stop simultaneously. When the first valve body dispenses glue from A1 to B1, the second valve body compensates for the coordinate spacing between the glue points on the product, allowing glue to be dispensed simultaneously on products at different angles and positions.

[0074] In this embodiment, when multiple valve bodies are used for dispensing, each valve body uses a separate control channel, and the following still takes a double valve as an example. Figure 7 As shown in the figure, assume that two valves are dispensing products 1 and 4. The single-shot weight (SW1) of the first valve body is 0.25 mg, the single-shot weight (SW2) of the second valve body is 0.3 mg, the dispensing circumference (L) of products 1 and 4 is 30 mm, and the glue weight (W) required for each product is 10 mg. Therefore, the number of drops required by the first valve body (N1) = W / SW1 = 40 drops, and the number of drops required by the second valve body (N2) = W / SW2 = 33.3333 drops, rounded to 33 drops (this can be adjusted for rounding or subtraction during the specific process flow, at the user's discretion). If all valves use a single control channel and the number of drops is the same at 40, the second valve body will dispense 2 mg more glue, over 20%, which is undoubtedly unacceptable.

[0075] In this embodiment, each valve uses a separate control channel for position comparison and output. That is, each time the main three-axis module moves a certain distance, it determines that it has reached an output point, and the judgment period is in nanoseconds. As mentioned above, the dispensing circumference (L) of product No. 1 and product No. 4 is 30 mm. The first valve body needs to dispense 40 drops of glue (N1) and the second valve body needs to dispense 33 drops of glue (N2). Considering that it is a closed figure, the last point and the first point cannot overlap. The dispensing spacing of the first valve body = L / N1=0.75mm (that is, one glue dot is output for every 0.75mm of movement), and the dispensing spacing of the second valve body = L / N2=0.909mm (that is, one glue dot is output for every 0.909mm of movement); if it is a non-closed image, the dispensing spacing = L / (N-1).

[0076] In this embodiment, since the auxiliary three-axis module only plays the function of dispensing position compensation during movement; the displacement length and start and end time of the movement of the first valve body and the second valve body themselves are consistent, and the first valve body is on the main three-axis module, and the auxiliary three-axis module is not used, the glue discharge control of the second valve body can also use the movement distance of the main three-axis module like the first valve body.

Claims

1. A multi-valve dispensing interpolation algorithm, characterized in that: It includes the following steps: A. Use visual shooting equipment to calibrate the positions of several valve bodies and calculate the distance between each two adjacent valve bodies; B. Use visual camera equipment to locate the positions of several products and calculate the position deviation MD and angle deviation RD of each product; C. With the coordinates of the first valve body as the origin, the product dispensed by the valve body is automatically distributed based on the distance FD between the valve bodies; D. When using a robot to control several valve bodies for dispensing, interpolate the motion algorithm of the robot; E. When using several valve bodies for dispensing, each valve body uses a separate control channel; The manipulator includes a main three-axis module and a secondary three-axis module, wherein the secondary three-axis module is arranged on the main three-axis module, a first valve body is arranged at the movable end of the main three-axis module, and a second valve body is arranged at the movable end of the secondary three-axis module; the method for calculating the distance between each two adjacent valve bodies includes the following steps: A1. Reset the main three-axis module and the secondary three-axis module; A2. The coordinates of all axes of the main three-axis module and the secondary three-axis module are set to 0; A3. Drive the main three-axis module to move the first valve body to the appropriate dispensing position; A4. Control the first valve body to dispense glue and record the glue dispensing position at this time as F (X1, Y1, Z1); A5. Drive the main three-axis module until the visual camera can see the glue dot on the first valve body. Align the center of the visual camera's field of view with the center of the glue dot, and record the camera's photographic coordinates as C (X2, Y2, Y2). A6. Calculate the distance D1=FC between the center of the field of view and the center of the glue point; A7. Similarly, the second valve body obtains the coordinate difference D2 between the center of the field of view and the center of the glue point according to steps A1-A6; A8. After all valve positions are calibrated, calculate the distance between adjacent valves (FD = D1 - D2).

2. A multi-valve dispensing interpolation algorithm according to claim 1, characterized in that: The method for calculating the position deviation MD and the angle deviation RD comprises the following steps: B1. Place a product in the field of view of the visual capture device; B2. Find two reference points on the product, create a visual template, and after teaching, move the center of the visual field to the center of the reference points. Record the photo positions as M1 and M2. The center of the product is M = (M1 + M2) / 2. B3. Teach the dispensing process. The product cannot be moved during the whole process. B4. Place the product for production. When the visual camera reaches M1 and M2, it takes a picture. The visual camera can determine the offset value of the first reference point as (Dx1, Dy1) and the offset value of the second reference point as (Dx2, Dy2). These values ​​are converted to the actual coordinates M1' and M2'. The center of the product is M' = (M1' + M2') / 2. B5. Calculate the product position deviation as MD = M-M'; B6. Calculate the angular deviation of the product. Given the two line segments formed by M1, M2 and M1', M2', find the angle between the line segments.

3. The multi-valve dispensing interpolation algorithm according to claim 1, characterized in that: The motion algorithm comprises the following steps: D1 drives the secondary three-axis module so that the distance between the first valve body and the second valve body is equal to the distance between the two products; D2 drives the Z axis of the main three-axis module and the secondary three-axis module to move the first valve body and the second valve body to the appropriate dispensing height; D3. During interpolation dispensing, the main three-axis module is responsible for completing the movement of one of the products; D4. The secondary three-axis module is responsible for compensating for the movement of the main three-axis module, so that the first valve body on the main three-axis module dispenses glue on one product while the second valve body dispenses glue on another product; D5. As the main three-axis module moves, the secondary three-axis module also moves accordingly. Due to the characteristics of interpolation motion, the speeds of the axes are automatically distributed, allowing them to start and stop simultaneously. When the first valve body is dispensing glue, the second valve body compensates for the coordinate spacing between the glue points on the product, allowing glue to be dispensed to products at different angles and positions simultaneously.

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