A method for calibrating a rotary rubber tip

Abstract

The present application belongs to the technical field of automatic dispensing, and provides a rotary glue head calibration method, a sensor base is installed below the glue head, a distance measuring sensor and a photoelectric sensor are installed on the sensor base, the length of the glue head is measured by the distance measuring sensor to determine the compensation amount in the length direction of the glue head; the photoelectric sensor is used as a position sensing device at the end of the glue head, and the real-time coordinate value when the end triggers the position signal during the movement of the glue head is recorded. The rotary glue head calibration method of the present application obtains the compensation amount in the length direction of the glue head, and the maximum amount of deviation from the center line and the corresponding rotation angle of the deviation amount to compensate the actual dispensing position of the dispensing machine, thereby ensuring the accuracy of the dispensing position. The implementation of the method of the present application only needs to use a distance measuring sensor and a photoelectric sensor, the installation space is small, different diameter glue heads do not need to replace the detection template, the operation is simple, and the accuracy of the dispensing position is greatly improved.

Description

Technical Field

[0001] This invention belongs to the field of automatic dispensing technology, and specifically relates to a method for calibrating a rotating dispensing head. Background Technology

[0002] During the operation of an automatic dispensing machine, it is necessary to frequently change the dispensing gun or dispensing head. Dispensing head calibration is a key factor that determines the dispensing accuracy of a multi-axis automatic dispensing machine. Among them, dispensing head calibration is a difficult problem. The market generally uses camera recognition to locate the dispensing dot image for calibration, which is costly, requires a large installation space, and requires changing the detection template for dispensing heads of different diameters, increasing the difficulty of operation.

[0003] Based on this, the present invention proposes a rotating rubber head calibration method, which can realize the end calibration function of the rubber head by using only a photoelectric sensor and a distance sensor, and can adapt to rubber heads of different diameters. Summary of the Invention

[0004] To address the problems existing in the background art, the present invention provides a method for calibrating a rotating rubber head, which includes the following steps:

[0005] A sensor base is installed below the rubber nozzle. A distance sensor and a photoelectric sensor are installed on the sensor base. The distance sensor is used to measure the length of the rubber nozzle and determine the compensation amount in the length direction of the rubber nozzle. The photoelectric sensor is used as a positioning sensing device at the end of the rubber nozzle to record the real-time coordinate value when the end of the rubber nozzle triggers the positioning signal during the movement of the rubber nozzle.

[0006] Set the X, Y, and Z directions of the rubber head, with the direction corresponding to the rotation axis of the rubber head being the Z direction; the probe axis of the ranging sensor is located in a plane perpendicular to and bisecting the sensing lines of the photoelectric sensor; set the maximum offset ζ of the end of the rotating rubber head relative to the rotation center line and the rotation angle α corresponding to this offset;

[0007] The entire process is divided into three stages: calibration, testing, and compensation.

[0008] The calibration process is as follows:

[0009] S1: Move the dispensing head of the dispensing machine to position A, so that the dispensing head is perpendicular to the distance sensor, and at the same time the end of the dispensing head is within the range of the sensor. Collect the value s0 of the dispensing gun end relative to the distance sensor. The X-direction reading at position A is x0.

[0010] S2: Move the glue gun to position B in the Z direction, and the glue head to the angle 0°. At this time, the bottom of the glue head is just flush with the bottom of the sensing line of the photoelectric sensor. If the glue head is beveled, the upper edge of the beveled glue head is flush with the bottom of the sensing line of the photoelectric sensor. The Z direction coordinate of the glue dispensing machine at this position is z0.

[0011] S3: Move the glue gun horizontally towards the photoelectric sensor to position C, and record the X coordinate x1 of the dispensing machine when the photoelectric sensor senses the end of the glue head during the movement;

[0012] S4: Move the dispensing head horizontally to position B, and record the X coordinate x2 of the dispensing machine when the photoelectric sensor reaches the end of the dispensing head during the movement;

[0013] S5: Move the glue head to an angle of 180°, move the glue head to position C, and then return to position B. Record the X coordinates x3 and x4 of the dispensing machine when the photoelectric sensor senses the end of the glue head during the two translations.

[0014] S6: Based on symmetry, the distance between position D and position A when the photoelectric sensor senses the rotation center line of the glue head can be obtained through the above process as: d0=|(x1+x2) / 2-x0+(x3+x4) / 2-x0|.

[0015] Furthermore, an inspection needs to be performed each time the rubber head becomes misaligned or when the rubber head is replaced. The inspection process is as follows:

[0016] P1: Install the actual dispensing nozzle, control the dispensing machine to move the nozzle to position A, and collect the value s1 of the end of the glue gun relative to the distance sensor;

[0017] P2: Move the glue gun to position B1 in the Z direction and rotate the glue head to an angle of 0°. At this position, the Z direction coordinate of the glue dispensing machine is z2 = z0 + (s1 - s0).

[0018] P3: Move the dispensing head to position C, then return to position B. Record the X coordinates x5 and x6 of the dispensing machine when the photoelectric sensor detects the end of the dispensing head during the two translations.

[0019] P 4. Rotate the glue head to an angle of 90°, move the glue head to position C, and then return to position B. Record the X coordinates x7 and x8 of the dispensing machine when the photoelectric sensor senses the end of the glue head during the two translations.

[0020] P5: From the above process, we can obtain that when the rotation angle of the rotating head is 0°, the deviation of the end of the head in the X direction relative to the rotation center line is:

[0021] ζ1 = |(x5+x6) / 2 - x0| - d0

[0022] The deviation of the tip of the rubber nozzle in the Y direction relative to the rotation center line is:

[0023] ζ2=|(x7+x8) / 2-x0|-d0

[0024] The maximum offset of the tip of the rubber head relative to the rotation center line is:

[0025] ζ =

[0026] The included angle corresponding to the maximum offset of the tip of the rubber head relative to the rotation center line is:

[0027]

[0028] When ζ1=0, ζ2>=0, α=90°;

[0029] When ζ1=0, ζ2<=0, α=270°;

[0030] When ζ1>0, m=0;

[0031] When ζ1 < 0, m = 1.

[0032] Furthermore, the compensation process is as follows:

[0033] The compensation process is applied to all actual dispensing trajectories. Assuming the dispensing head rotation angle is β, the target coordinates for dispensing are O(x,y,z). Due to varying head lengths and potential skew, the actual coordinates the dispensing machine needs to move are O... ’ (x ’ ,y',z ’ The calculation formula for the rubber head compensation process is as follows:

[0034] x ’ = x + ζ * cos(α + β);

[0035] y ’ = y+ζ*sin(α+β);

[0036] z ’ = z + (s1 - s0).

[0037] The beneficial effects achieved by this invention are as follows:

[0038] This invention provides a method for calibrating a rotating dispensing head. It obtains the length-direction compensation of the dispensing head, the maximum offset relative to the rotation center line, and the corresponding rotation angle. This information is then used to compensate for the planned position of the dispensing machine during actual dispensing, ensuring accurate dispensing positioning. This method requires only a distance sensor and a photoelectric sensor to acquire data from the dispensing head. It requires minimal installation space, eliminates the need to change the detection template for dispensing heads of different diameters, and is simple to operate, significantly improving the accuracy of the dispensing position. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of the rubber head calibration device and coordinate system settings;

[0040] Figure 2 This is a schematic diagram of the rubber head calibration process;

[0041] Figure 3 This is a schematic diagram of the rubber head testing process.

[0042] Numbering on the map:

[0043] 1. Sensor base; 2. Distance sensor; 3. Adhesive head; 4. Photoelectric sensor. Detailed Implementation

[0044] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. In addition, the forms of the various structures described in the following embodiments are merely illustrative. The present invention is not limited to the structures described in the following embodiments. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0045] Reference Figure 1-3 The present invention provides a method for calibrating a rotating dispensing head 3 that only requires a distance sensor 2 and a photoelectric sensor 4 to collect data on the dispensing head 3. A sensor base 1 is installed below the dispensing head 3, and the distance sensor 2 and the photoelectric sensor 4 are installed on the sensor base 1. The former is used to measure the length of the dispensing head 3, that is, to determine the compensation amount in the length direction of the dispensing head 3. The latter serves as a position sensing device at the end of the dispensing head 3 of the dispensing machine, and can be used to record the real-time coordinate value when the end triggers the position signal during the movement of the dispensing machine. In practical applications, the position difference between the rotation center and the photoelectric sensor 4 is first calculated using symmetry. Then, the dispensing head 3 is rotated by 90 degrees to trigger the photoelectric sensor 4, and the coordinate value is recorded. Finally, the maximum amount of offset of the end of the dispensing head 3 relative to the rotation center line and the rotation angle corresponding to the offset are calculated using the above coordinate data.

[0046] For ease of description, a gantry-type four-axis dispensing machine is used as an example, with the X, Y, and Z directions of the dispensing machine set simultaneously as follows: Figure 1 As shown, the rotation axis of the rotating glue head 3 corresponds to the Z-direction, and the probe axis of the ranging sensor 2 lies in a plane perpendicular to and bisecting the sensing line of the photoelectric sensor 4, and this plane is parallel to the XZ plane. The maximum offset ζ of the end of the glue head 3 relative to the rotation center line and the corresponding rotation angle α are set. The entire process is divided into three steps: calibration, detection, and compensation. For the same device, calibration only needs to be performed once. The calibration process is as follows: Figure 2 As shown.

[0047] 1. Select any glue head 3 and control the dispensing machine to move glue head 3 to position A, so that glue head 3 is perpendicular to distance sensor 2, and at the same time the end of glue head 3 is within the range of sensor. Collect the value s0 of glue gun end relative to distance sensor 2. The reading in the X direction at position A is x0.

[0048] 2. Move the glue gun to position B in the Z direction, and rotate the glue head 3 to an angle of 0°. At this time, the bottom of the glue head 3 is just flush with the bottom of the sensing line of the photoelectric sensor 4 (if the glue head 3 is beveled, the upper edge of the bevel of the glue head 3 is flush with the bottom of the sensing line of the photoelectric sensor 4). The Z-axis coordinate of the glue dispensing machine at this position is z0.

[0049] 3. Move the glue gun horizontally to position C in the direction of the photoelectric sensor 4 with the glue head 3, and record the X coordinate x1 of the dispensing machine when the photoelectric sensor 4 senses the end of the glue head 3 during the movement.

[0050] 4. Move the dispensing head 3 horizontally to position B, and record the X coordinate x2 of the dispensing machine when the photoelectric sensor 4 reaches the end of the dispensing head 3 during the movement;

[0051] 5. Rotate the dispensing head 3 to an angle of 180°, move the dispensing head 3 to position C, and then return to position B. Record the X coordinates x3 and x4 of the dispensing machine when the photoelectric sensor 4 senses the end of the dispensing head 3 during the two translations.

[0052] Based on symmetry, the distance between position D and position A when the photoelectric sensor 4 senses the rotation center line of the glue head 3 can be obtained through the above process.

[0053] d0 = |(x1+x2) / 2-x0+(x3+x4) / 2-x0|;

[0054] A test needs to be performed each time the rubber head 3 becomes misaligned or when the rubber head 3 is replaced. The test process is as follows: Figure 3 As shown.

[0055] 1. Install the actual dispensing head 3, control the dispensing machine to move the dispensing head 3 to position A, and collect the value s1 of the end of the glue gun relative to the distance sensor 2;

[0056] 2. Move the glue gun to position B1 in the Z direction, and rotate the glue head 3 to an angle of 0°. At this position, the Z direction coordinate of the glue dispensing machine is z2 = z0 + (s1 - s0).

[0057] 3. Move the glue head 3 to position C, and then return to position B. Record the X coordinates x5 and x6 of the dispensing machine when the photoelectric sensor 4 senses the end of the glue head 3 during the two translations.

[0058] 4. Rotate the dispensing head 3 to an angle of 90°, move the dispensing head 3 to position C, and then return to position B. Record the X coordinates x7 and x8 of the dispensing machine when the photoelectric sensor 4 senses the end of the dispensing head 3 during the two translations.

[0059] From the above process, we can conclude that when the rotation angle of the rotating head 3 is 0°, the deviation of the end of the head 3 in the X direction relative to the rotation center line is:

[0060] ζ1 = |(x5+x6) / 2 - x0| - d0

[0061] The deviation of the end of the rubber head 3 in the Y direction relative to the rotation center line is:

[0062] ζ2=|(x7+x8) / 2-x0|-d0

[0063] The maximum offset of the end of the rubber head 3 relative to the rotation center line is

[0064] ζ =

[0065] The included angle corresponding to the maximum offset of the end of the rubber head 3 relative to the rotation center line is:

[0066]

[0067] When ζ1=0, ζ2>=0, α=90°;

[0068] When ζ1=0, ζ2<=0, α=270°;

[0069] When ζ1>0, m=0;

[0070] When ζ1 < 0, m = 1.

[0071] The compensation process is applied to all actual dispensing trajectories. Assuming the dispensing head 3 rotates at an angle of β, the target coordinates for dispensing are O(x,y,z). Due to the varying lengths of the dispensing head 3 and the presence of skew, the actual coordinates the dispensing machine needs to move are O(x,y,z). ’ (x ’ ,y',z ’ The calculation formula for the compensation process of rubber head 3 is as follows:

[0072] x ’ = x + ζ * cos(α + β);

[0073] y ’ = y+ζ*sin(α+β);

[0074] z ’ = z + (s1 - s0).

[0075] 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, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for calibrating a rotating rubber head, characterized in that, It includes the following steps: A sensor base is installed below the rubber head. A distance sensor and a photoelectric sensor are installed on the sensor base. The distance sensor is used to measure the length of the rubber head and determine the compensation amount in the length direction of the rubber head. The photoelectric sensor is used as the positioning sensing device at the end of the rubber head to record the real-time coordinate value when the end of the rubber head triggers the positioning signal during the movement of the rubber head. Set the X, Y, and Z directions of the rubber head, with the direction corresponding to the rotation axis of the rubber head being the Z direction; the probe axis of the ranging sensor is located in a plane perpendicular to and bisecting the sensing lines of the photoelectric sensor; set the maximum offset ζ of the end of the rotating rubber head relative to the rotation center line and the rotation angle α corresponding to this offset; The entire process is divided into three stages: calibration, testing, and compensation. S1: Move the dispensing head of the dispensing machine to position A, so that the dispensing head is perpendicular to the distance sensor, and at the same time the end of the dispensing head is within the range of the sensor. Collect the value s0 of the dispensing gun end relative to the distance sensor. The X-direction reading at position A is x0. S2: Move the glue gun to position B in the Z direction, and the glue head to the angle 0°. At this time, the bottom of the glue head is just flush with the bottom of the sensing line of the photoelectric sensor. If the glue head is beveled, the upper edge of the beveled glue head is flush with the bottom of the sensing line of the photoelectric sensor. The Z direction coordinate of the glue dispensing machine at this position is z0. S3: Move the glue gun horizontally towards the photoelectric sensor to position C, and record the X coordinate x1 of the dispensing machine when the photoelectric sensor senses the end of the glue head during the movement; S4: Move the dispensing head horizontally to position B, and record the X coordinate x2 of the dispensing machine when the photoelectric sensor reaches the end of the dispensing head during the movement; S5: Move the glue head to an angle of 180°, move the glue head to position C, and then return to position B. Record the X coordinates x3 and x4 of the dispensing machine when the photoelectric sensor senses the end of the glue head during the two translations. S6: Based on symmetry, the distance between position D and position A when the photoelectric sensor senses the rotation center line of the glue head can be obtained through the above process as: d0=|(x1+x2) / 2-x0+(x3+x4) / 2-x0|; A test is required each time the rubber head becomes misaligned or when the rubber head is replaced. The test process is as follows: P1: Install the actual dispensing nozzle, control the dispensing machine to move the nozzle to position A, and collect the value s1 of the end of the glue gun relative to the distance sensor; P2: Move the glue gun to position B1 in the Z direction and rotate the glue head to an angle of 0°. At this position, the Z-direction coordinate of the glue dispensing machine is z2 = z0 + (s1 - s0). P3: Move the dispensing head to position C, then return to position B. Record the X coordinates x5 and x6 of the dispensing machine when the photoelectric sensor detects the end of the dispensing head during the two translations. P4. Rotate the glue head to an angle of 90°, move the glue head to position C, and then return to position B. Record the X coordinates of the dispensing machine, x7 and x8, when the photoelectric sensor senses the end of the glue head during the two translations. P5: From the above process, we can obtain that when the rotation angle of the rotating head is 0°, the deviation of the end of the head in the X direction relative to the rotation center line is: ζ1 = |(x5+x6) / 2 - x0| - d0 The deviation of the tip of the rubber nozzle in the Y direction relative to the rotation center line is: ζ2=|(x7+x8) / 2-x0|-d0 The maximum offset of the tip of the rubber head relative to the rotation center line is: g = The included angle corresponding to the maximum offset of the tip of the rubber head relative to the rotation center line is: When ζ1=0, ζ2>=0, α=90°; When ζ1=0, ζ2<=0, α=270°; When ζ1>0, m=0; When ζ1 < 0, m = 1; The compensation process is as follows: The compensation process is applied to all actual dispensing trajectories. Assuming the dispensing head rotation angle is β, the target coordinates for dispensing are O(x,y,z). Due to varying head lengths and potential skew, the actual coordinates the dispensing machine needs to move are O... ’ (x ’ ,y',z ’ The calculation formula for the rubber head compensation process is as follows: x ’ = x+ζ*cos(α+β); y ’ = y+ζ*sin(α+β); With ’ = z+(s1-s0)。

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