A method for calibrating the pose relationship between a robot and a turntable using a laser tracker

Abstract

The present invention discloses a method for calibrating the pose relationship between a robot and a turntable by using a laser tracker, including: Step 1: Divide the robot base into several regions and mark them; Step 2: Fix the laser tracker at a position between the robot base and the turntable. By placing several laser tracker accessories in several regions respectively, collect and record; Step 3: The robot is positioned on the robot base. Place several laser tracker accessories in the robot respectively, collect and record; Step 4: Place the laser tracker accessory at a fixed position on the turntable. By controlling the rotation of the turntable, rotate at intervals of 1 degree each time and record in sequence; Step 5: Change the fixed position of the laser tracker accessory. By controlling the rotation of the turntable, rotate at intervals of 1 degree each time and record in sequence. The present invention uses a laser tracker to calibrate the position relationship between the robot and the turntable, and maximally avoids the calibration errors caused by manual intervention.

Description

Technical Field

[0001] The present invention relates to the technical field of robots, and particularly to a method for calibrating the pose relationship between a robot and a turntable using a laser tracker. Background Art

[0002] With the improvement of modern technology and the enhancement of living quality, the demand for new material products is increasing day by day. Carbon fiber products have always been a typical representative of new materials due to their high strength and light weight. However, due to their manufacturing difficulty and low yield rate, they have mainly been used in the aerospace and other high-value-added fields in the past, and have gradually been extended to civilian use in recent years.

[0003] The manufacturing process of carbon fiber products is extremely complex. The grinding process is an essential step from raw materials to finished products and directly determines whether the product is a qualified one. The main difficulty lies in the grinding accuracy. The so-called "accuracy" actually consists of many aspects, such as the accuracy of the fixture, the accuracy of the grinding tool, the accuracy of the grinding trajectory, etc. The current mainstream grinding solution is to pre-generate the grinding trajectory according to the workpiece shape by offline software and cooperate with a high-precision robot to achieve precise grinding. Through such an almost automated solution, the grinding accuracy can be guaranteed to the greatest extent, thus ensuring the yield rate of carbon fiber products. However, there is a technical point that cannot be bypassed in this kind of solution, that is, how to make the robot know the position of the turntable fixture.

[0004] The existing calibration methods generally require first placing a calibration plate with a known dot pitch accurately at the center of the turntable. After that, all subsequent steps use the calibration plate to replace the turntable. Then, manually operate the robot to make three different poses of the robot point to the same position in space simultaneously, so as to obtain the robot's end coordinate system (abbreviation: TCP). This step can generally be directly obtained by the built-in algorithm of industrial robots. Subsequently, the position relationship between the turntable and the robot is generated by the teaching three-point method (origin, x direction, y direction). Such methods rely too much on the experience of the operator and the proficiency and accuracy of the taught points, and the operation is also relatively cumbersome. Summary of the Invention

[0005] Aiming at the above problems existing in the existing calibration, the present invention aims to provide a method for calibrating the pose relationship between a robot and a turntable using a laser tracker, using the laser tracker to calibrate the position relationship between the robot and the turntable, and maximizing the avoidance of calibration errors caused by manual intervention.

[0006] The specific technical solution is as follows:

[0007] A method for calibrating the pose relationship between a robot and a turntable using a laser tracker, comprising: a robot, a robot base, a turntable, a laser tracker, and a plurality of laser tracker accessories;

[0008] The method includes:

[0009] Step 1: Divide the robot base into several areas and mark them.

[0010] Step 2: Fix the laser tracker at the position between the robot base and the turntable. By placing several laser tracker accessories in several of the areas respectively, collect and record the spatial positions of the laser tracker accessories in the coordinate system of the laser tracker, namely the three values of X, Y, and Z, and record them as point set 1.

[0011] Step 3: The robot is positioned on the robot base. Place several laser tracker accessories in two precise positioning holes of the robot respectively, collect and record the spatial positions of the laser tracker accessories in the coordinate system of the laser tracker, namely the three values of X, Y, and Z, and record them as point set 2.

[0012] Step 4: Place the laser tracker accessory at a fixed position on the turntable, denoted as fixed position 1. By controlling the rotation of the turntable, rotate it at intervals of 1 degree each time, and sequentially record the spatial positions of the laser tracker accessory in the coordinate system of the laser tracker, namely the three values of X, Y, and Z, and record them as point set 3.

[0013] Step 5: Replace the fixed position of the laser tracker accessory, denoted as fixed position 2. By controlling the rotation of the turntable, rotate it at intervals of 1 degree each time, and sequentially record the spatial positions of the laser tracker accessory in the coordinate system of the laser tracker, namely the three values of X, Y, and Z, and record them as point set 4.

[0014] Step 6: Through point set 1, point set 2, point set 3, and point set 4, finally calculate the pose relationship of the turntable relative to the robot, namely the values of X, Y, Z, Rx, Ry, and Rz.

[0015] In the above method for calibrating the pose relationship between a robot and a turntable using a laser tracker, in step 1, the robot base is divided into several areas at equal intervals.

[0016] In the above method for calibrating the pose relationship between a robot and a turntable using a laser tracker, in step 1, mark several of the areas with an oil-based pen.

[0017] In the above method for calibrating the pose relationship between a robot and a turntable using a laser tracker, the laser tracker accessory is a target ball.

[0018] The above method for calibrating the pose relationship between a robot and a turntable using a laser tracker, wherein, in Steps 4 and 5, the turntable is controlled to rotate at intervals of 1° each time, and the positions of 360 laser tracker accessories are recorded.

[0019] The above method for calibrating the pose relationship between a robot and a turntable using a laser tracker, wherein, in Step 2, the distance between the laser tracker and the turntable is 1 m to 5 m.

[0020] The above method for calibrating the pose relationship between a robot and a turntable using a laser tracker further includes: a turntable motor and a robot driver, wherein the robot driver is in signal connection with the turntable motor, and the turntable motor is in transmission connection with the turntable.

[0021] The positive effects of the above technical solution compared with the prior art are:

[0022] The present invention uses a laser tracker to calibrate the pose relationship between a robot and a turntable, which can accurately and efficiently calibrate the pose relationship between the robot and the turntable, and maximize the avoidance of calibration errors caused by manual intervention. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a schematic diagram of a method for calibrating the pose relationship between a robot and a turntable using a laser tracker according to the present invention;

[0024] Figure 2 is a flowchart of a method for calibrating the pose relationship between a robot and a turntable using a laser tracker according to the present invention;

[0025] In the drawings: 1, robot base; 2, turntable; 3, laser tracker; 4, laser tracker. DETAILED DESCRIPTION OF THE INVENTION

[0026] The present invention will be further described below in conjunction with the drawings and specific embodiments, but it is not intended to limit the present invention.

[0027] Figure 1 is a schematic diagram of a method for calibrating the pose relationship between a robot and a turntable using a laser tracker according to the present invention;

[0028] Figure 2 is a flowchart of a method for calibrating the pose relationship between a robot and a turntable using a laser tracker according to the present invention, as Figures 1 to 2 shown, showing a method for calibrating the pose relationship between a robot and a turntable using a laser tracker in a preferred embodiment, including: a robot 3, a robot base 1, a turntable 2, a laser tracker 4, and a plurality of laser tracker accessories.

[0029] Further, as a preferred embodiment, the method includes:

[0030] Step 1: Divide the robot base 1 into several areas and mark them;

[0031] Step 2: Fix the laser tracker 4 at the position between the robot base 1 and the turntable 2. By placing several laser tracker accessories in several areas respectively, collect and record the spatial positions of the laser tracker accessories in the coordinate system of the laser tracker 4, that is, the three values of X, Y, and Z, and record them as point set 1;

[0032] Step 3: The robot 3 is placed on the robot base 1. Place several laser tracker accessories in the two fine positioning holes of the robot 3 respectively, collect and record the spatial positions of the laser tracker accessories in the coordinate system of the laser tracker 4, that is, the three values of X, Y, and Z, and record them as point set 2;

[0033] Step 4: Place the laser tracker accessory at a fixed position on the turntable 2, denoted as fixed position 1. By controlling the rotation of the turntable 2, rotate it at intervals of 1 degree each time, and sequentially record the spatial positions of the laser tracker accessory in the coordinate system of the laser tracker 4, that is, the three values of X, Y, and Z, and record them as point set 3;

[0034] Step 5: Replace the fixed position of the laser tracker accessory, denoted as fixed position 2. By controlling the rotation of the turntable 2, rotate it at intervals of 1 degree each time, and sequentially record the spatial positions of the laser tracker accessory in the coordinate system of the laser tracker 4, that is, the three values of X, Y, and Z, and record them as point set 4;

[0035] Step 6: Through point set 1, point set 2, point set 3, and point set 4, finally calculate the pose relationship of the turntable relative to the robot, that is, the values of X, Y, Z, Rx, Ry, and Rz.

[0036] The above is only a preferred embodiment of the present invention, and does not limit the implementation manners and protection scope of the present invention accordingly.

[0037] The present invention also has the following implementation manners on the above basis:

[0038] In a further embodiment of the present invention, please continue to refer to Figures 1 to 2 As shown, in Step 1, divide the robot base into several areas at equal intervals.

[0039] In a further embodiment of the present invention, in Step 1, mark several areas with an oil-based pen.

[0040] In a further embodiment of the present invention, the laser tracker accessory is a target ball.

[0041] In a further embodiment of the present invention, in Steps 4 and 5, control the turntable 2 to rotate at intervals of 1° each time, and record the positions of 360 laser tracker accessories.

[0042] In a further embodiment of the present invention, in step two, the distance between the laser tracker 4 and the turntable 2 is 1 m to 5 m.

[0043] In a further embodiment of the present invention, the method for calibrating the pose relationship between the robot and the turntable using a laser tracker further includes: a turntable motor and a robot driver, the robot driver is signal-connected to the turntable motor, and the turntable motor is drivingly connected to the turntable 2.

[0044] Specific embodiments of the present invention:

[0045] The robot base 1 and the turntable 2 are positioned and fixed, the laser tracker 4 is placed between the robot base 1 and the turntable 2, at positions about 2 m apart respectively, and an equilateral triangle is formed among the three. Fix the laser tracker 4 so that it is not allowed to be moved before the calibration is completed. Turn on the laser tracker 4 and let it warm up fully.

[0046] Use an oil-based pen to equally divide 98 regions on the robot base 1, and place the laser target balls in these regions in turn. Record the position set of the target balls through the feedback data of the laser tracker 4.

[0047] Install the robot 3 on the robot base 1 and fix it completely. Place the target balls in the two fine positioning holes of the robot respectively, and record the positions of the two target balls through the feedback data of the laser tracker 4.

[0048] Connect the turntable motor to the robot driver to ensure that the robot 3 can control the rotation of the turntable 2. Fix the target ball at any position on the turntable. Control the turntable to rotate at intervals of 1° each time, and record the positions of 360 target balls.

[0049] Change the position of the target ball and fix it, repeat the above steps, and also record the positions of 360 target balls. Calculate the pose relationship between the turntable and the robot body from the above data.

[0050] The present invention uses the laser tracker 4 to calibrate the pose relationship between the robot 3 and the turntable 2, and can accurately and efficiently calibrate the pose relationship between the robot 3 and the turntable 2, and maximize the avoidance of calibration errors caused by manual intervention.

[0051] The above are only the preferred embodiments of the present invention, and do not limit the implementation manners and protection scope of the present invention accordingly. For those skilled in the art, it should be able to realize that any equivalent replacement and obvious changes made by using the description and illustrations of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for calibrating the pose relationship between a robot and a turntable using a laser tracker, characterized in that, include: Robot, robot base, turntable, laser tracker and several laser tracker accessories; The method comprises: Step 1: Divide the robot base into several areas and mark them; Step 2: Fix the laser tracker at a position between the robot base and the turntable, and place several laser tracker accessories in the several areas respectively, collect and record the spatial positions of the laser tracker accessories relative to the laser tracker in the coordinate system, that is, the three values ​​of X, Y, and Z, and record them as point set 1; Step 3: the robot is positioned on the robot base, and a number of the laser tracker accessories are respectively placed in the two precise positioning holes of the robot, and the spatial positions of the laser tracker accessories relative to the coordinate system of the laser tracker, that is, the three values ​​of X, Y, and Z, are collected and recorded as point set 2; Step 4: placing the laser tracker auxiliary component on a fixed position on the turntable, recorded as fixed position 1, controlling the turntable to rotate, each time with an interval of 1 degree, and sequentially recording the spatial position of the laser tracker auxiliary component relative to the laser tracker coordinate system, that is, the three values ​​of X, Y, and Z, recorded as point set 3; Step 5: Change the fixed position of the laser tracker auxiliary component, recorded as fixed position 2, control the turntable to rotate, rotate 1 degree at a time, and record the spatial position of the laser tracker auxiliary component relative to the laser tracker coordinate system, that is, the three values ​​of X, Y, and Z, in sequence, and record them as point set 4; Step six: finally calculate the position relationship of the turntable relative to the robot, that is, the values ​​of X, Y, Z, Rx, Ry, and Rz, through the point set 1, the point set 2, the point set 3, and the point set 4.

2. The method for calibrating the pose relationship between a robot and a turntable using a laser tracker according to claim 1, characterized in that, In step one, the robot base is divided into a plurality of areas at equal intervals.

3. The method for calibrating the pose relationship between a robot and a turntable using a laser tracker according to claim 1, wherein In step one, a number of the areas are marked with a marker.

4. The method for calibrating the pose relationship between a robot and a turntable using a laser tracker according to claim 1, characterized in that The laser tracker auxiliary part is a target ball.

5. The method for calibrating the pose relationship between a robot and a turntable using a laser tracker according to claim 1, wherein In step 4 and step 5, the turntable is controlled to rotate at intervals of 1° each time, and 360 positions of the laser tracker auxiliary component are recorded.

6. The method for calibrating the pose relationship between a robot and a turntable using a laser tracker according to claim 1, characterized in that In step 2, the distance between the laser tracker and the turntable is 1 m to 5 m.

7. The method for calibrating the pose relationship between a robot and a turntable using a laser tracker according to claim 1, wherein Also includes: A turntable motor and a robot driver, wherein the robot driver is signal-connected to the turntable motor, and the turntable motor is transmission-connected to the turntable.

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