KR102685098B1 - Tcp calibration apparatus for welding robot and calibration method with the same - Google Patents

Abstract

This relates to a TCP calibration device for a welding robot and a calibration method using the same, which includes a tooltip installed at the tip of the torch of a welding robot and a calibration jig that is rotatably installed on the floor and has a moving space inside where the tooltip moves for TCP calibration. By providing a configuration including, the effect of being able to precisely calibrate the TCP of the welding robot is obtained using the distance the tool tip is moved in the movement space inside the calibration jig having preset horizontal and vertical lengths.

Description

TCP calibration device for welding robot and calibration method using the same {TCP CALIBRATION APPARATUS FOR WELDING ROBOT AND CALIBRATION METHOD WITH THE SAME}

The present invention relates to a TCP calibration device for a welding robot and a calibration method using the same. More specifically, it relates to a TCP calibration device for a welding robot that calibrates TCP (tool center point) when replacing a torch of a welding robot and a calibration method using the same. will be.

Generally, a welding robot is used with a torch fixed to the last axis of the welding robot (6th axis in the case of a 6-axis robot).

The relationship between the final axis of the welding robot and the torch remains largely constant, but slight changes inevitably occur due to wear of the welding rod, deformation of the mounting position due to shock or heat, etc.

Therefore, for more precise welding, TCP calibration, which indicates the relationship between the last axis of the welding robot and the torch, must be frequently performed.

For example, the present applicant disclosed the calibration technology of a welding robot in Patent Document 1 below and applied for and received a patent.

On the other hand, when welding is performed automatically by installing a robot as in conventional overhead lug automatic welding equipment, the torch of the welding robot must be replaced and then TCP (Tool Center Point) must be input to the controller.

Figure 1 is an exemplary diagram of a welding robot according to the prior art.

As shown in FIG. 1, TCP refers to the position and posture of the tip of the torch (2) when viewed based on the 6-axis coordinate system of the welding robot (1). That is, based on the origin of the 6th axis that rotates the torch 2 in the Rz direction, it indicates the degree to which the TCP is spaced apart in the x, y, and z directions and the rotation angle.

Therefore, the welding robot 1 performs tasks such as welding by moving the end of the wire to the desired position using the input TCP values (x, y, z, Rx, Ry, Rz).

Republic of Korea Patent Registration No. 10-1220877 (announced on January 11, 2013) Republic of Korea Patent Registration No. 10-1622659 (announced on May 20, 2016)

However, among TCP values, the x, y, and z values can be relatively easily calibrated in the field, but the Rz, Ry, and Rz values related to the torch's attitude are difficult to calibrate due to the difficulty of measuring them in the field.

Therefore, in the field, only the x, y, and z values of the TCP values (x, y, z, Rx, Ry, and Rz) are measured and calibrated.

Accordingly, there is always an error in the TCP value, and there is a problem of having to perform repeated TCP calibration.

In addition, as described above, manually performing TCP calibration has the problem of causing inconvenience and inconvenience during maintenance work on the welding robot.

The purpose of the present invention is to solve the problems described above and to provide a TCP calibration device for a welding robot that can automatically calibrate TCP values when a torch is replaced in the welding robot and a calibration method using the same.

Another object of the present invention is to provide a TCP calibration device for a welding robot that can precisely calibrate TCP values by installing a calibration jig and tool tip, and a calibration method using the same.

In order to achieve the above-described purpose, the TCP calibration device for a welding robot according to the present invention includes a tool tip installed at the tip of the torch of the welding robot, a movement space where the tool tip moves for TCP calibration, and a rotating space on the floor. It includes a calibration jig that can be installed, and the controller of the welding robot is characterized by calibrating the entire TCP value using the distance that the tool tip moves inside the moving space and the horizontal and vertical lengths and heights of the moving space. .

The tool tip includes a body coupled to the tip of the torch, a contact port formed in a spherical shape, and a connecting bar connecting the body and the contact port, and the contact port is It is characterized by movement in the axis, Y-axis, and Z-axis directions and in the Rx, Ry, and Rz directions.

The calibration jig includes a base installed on the floor, a body rotatably installed on the upper part of the base and forming a movement space within which the tool tip moves, and a body configured to calibrate x, y, and z axis values among the TCP values. It is characterized by including a plate extended to one side of the body.

A magnet is installed on the base to fix the calibration jig to the floor, the moving space has a square cross-section, and the body is rotatably installed on the upper part of the base about an axis installed on the lower surface, On the upper surface of the bottom plate of the body, a scale is displayed for each preset angle around the axis so that the rotation angle of the body can be checked.

In addition, in order to achieve the above-mentioned purpose, the calibration method using the TCP calibration device of the welding robot according to the present invention includes (a) installing a tool tip on the torch of the welding robot and rotatably installing a calibration jig on the floor. Step, (b) calculating the rotation angle of the calibration jig and aligning it in parallel with the welding robot, (c) moving the tooltip in the movement space inside the calibration jig to calibrate Rx, Ry, and Rz values among TCP values. and (d) calibrating x, y, and z values among TCP values using the side wall and plate of the calibration jig.

Step (b) includes (b1) executing a calibration program in the welding robot controller and arranging the tooltip so that its posture is parallel to the z-direction of the robot base using the currently stored TCP value, (b2) Controlling the contact port of the tool tip to move to a height that touches the top of the side wall of the calibration jig while maintaining the posture of the tool tip, (b3) moving the tool tip in the x and y directions of the robot base to change the distance and (b4) calculating the rotation angle of the calibration jig using the distance measured in step (b3) and rotating the calibration jig in the opposite direction by the calculated rotation angle to align it with the welding robot. It is characterized by comprising the step of:

Step (c) includes (c1) driving the welding robot so that the contact port of the tool tip is located inside the moving space of the calibration jig, (c2) rotating the tool tip in the z-axis direction of the 6-axis coordinate system, (c3) measuring the rotation angle by rotating the connection bar of the tool tip in both directions until it touches both side walls of the calibration jig; and (c4) calculating the error using the measured rotation angle in both directions and calculating the error from the TCP value. It is characterized by including a step of reflecting the Rz value.

The step (c) includes (c5) driving the welding robot to control the tool tip to rotate by the target rotation angle, and (c6) using the touch and relative movement functions of the welding robot to ensure that the center of the contact hole is at the first height. controlling the welding robot to be positioned, (c7) measuring the distance by driving the welding robot in the x-direction of the robot base, and calculating the actual rotation angle using the measured distance, and (c8) calculating the actual rotation angle and the target. It is characterized by including the step of calculating an error using the rotation angle and calibrating the calculated error by reflecting it on the Ry value among the TCP values.

Step (c) further includes the step (c9) of performing steps (c5) to (c8) in the same manner in the y direction of the robot base and calibrating the calculated error by reflecting it in the Rx value among the TCP values. It is characterized by

Step (d) includes (d1) installing the calibration jig on the bottom of the hull, and moving the welding robot around the calibration jig while maintaining the torch parallel to the home position where all axes have values of 0, (d2) using the touch function of the welding robot to control the tip of the torch to stop when it touches the side wall of the calibration jig, and recognizing the position of the point in front of the touched torch, (d3) moving the torch again to the above (d2) ) After returning to the initial position before performing the step, moving downward to recognize the position of the point at the bottom of the torch that touched the plate extended on one side of the calibration jig, (d4) the initial position and touch Calculating the distance between the points and calculating the coordinate value of the initial position based on the calibration jig, (d5) controlling the 5 axes that rotate the torch in the Ry direction to rotate at a random angle, and rotating the torch at different angles. calculating the coordinate values of the first and second rotated rotation positions; and (d6) calculating the center of the circle and the radius of the circle by obtaining the equation of the circle having the initial position and the first and second rotation positions, and calculating the calculated circle. It is characterized by including the step of calibrating z and x values among TCP values using the center of and the initial position.

In step (d), the tool tip is moved in the x-axis direction with the torch aligned with the y-axis direction of the robot base (d7), and the tip of the tool tip is controlled to stop when it touches the side wall of the calibration jig, and the initial position is maintained. Calculating the distance between and the touched point, (d8) returning the tooltip to the initial position and rotating it 180° in the z-axis direction based on the robot base from the initial position, (d9) the tooltip moving in the x-axis direction of the robot base and touching the side wall of the calibration jig to calculate the distance between the rotation position and the touched point; and (d10) calculating the y-axis direction error using the difference between the two calculated distances. and further comprising the step of calibrating the calculated y-axis direction error by reflecting it on the y value among the TCP values.

As described above, according to the TCP calibration device of the welding robot and the calibration method using the same according to the present invention, the TCP of the welding robot is The effect of being able to precisely calibrate is obtained.

According to the present invention, the effect of automatically calibrating the entire TCP value is obtained by installing a calibration jig and tool tip in the field and executing a calibration program in the controller of the welding robot.

Accordingly, according to the present invention, the effect of improving workability and maintaining good work quality is obtained by eliminating repetitive calibration due to errors in TCP when replacing a torch.

1 is an example of a welding robot according to the prior art;
Figure 2 is a configuration diagram of a TCP calibration device for a welding robot according to a preferred embodiment of the present invention;
Figure 3 is a top view of the calibration jig shown in Figure 2;
Figure 4 is a cross-sectional view of the calibration jig shown in Figure 2;
Figure 5 is a process diagram illustrating step by step the calibration method using the TCP calibration device of a welding robot according to a preferred embodiment of the present invention;
Figures 6 and 7 are examples illustrating the process of calculating the rotation angle of the calibration jig;
Figures 8 to 10 are diagrams illustrating the process of calculating the error of Rz value among TCP values;
Figures 11 to 13 are diagrams illustrating the process of calculating errors in Ry and Rx values among TCP values;
Figures 14 to 16 are diagrams illustrating the process of calibrating the x- and z-axis directions among TCP values;
Figure 17 is a diagram illustrating the process of calibrating the y-axis direction.

Hereinafter, a TCP calibration device for a welding robot and a calibration method using the same according to a preferred embodiment of the present invention will be described in detail with reference to the attached drawings.

Figure 2 is a configuration diagram of a TCP calibration device for a welding robot according to a preferred embodiment of the present invention.

Hereinafter, terms indicating directions such as 'left', 'right', 'front', 'rear', 'up' and 'down' are defined as indicating each direction based on the state shown in each drawing. do.

As shown in FIG. 2, the TCP calibration device 20 for a welding robot according to a preferred embodiment of the present invention includes a tool tip 30 installed at the tip of the torch 11 of the welding robot 10 and an internal device for TCP calibration. A space in which the tool tip 30 can move is formed and a calibration jig 40 is rotatably installed on the floor to correct TCP value errors.

The tool tip 30 includes a body 31 coupled to the tip of the torch 11, a contact hole 32 formed in a spherical shape, and a connecting bar 33 connecting the body 31 and the contact hole 32. can do.

The body 31 may be formed in a substantially cylindrical or conical shape with front and rear surfaces open so that it can be coupled to the front end of the torch 11 and the rear end of the connecting bar 33, respectively.

The contact hole 32 is disposed in the movement space 42 formed inside the calibration jig 40 and moves in the X-axis, Y-axis, and Z-axis directions and in the Rx, Ry, and Rz directions by the operation of the welding robot 10. can be moved to

The connecting bar 33 may be formed in a cylindrical shape with a preset thickness.

In Figure 2, 'd' is the thickness of the connecting bar 33, and '2r' is the diameter of the contact hole 32.

Next, the configuration of the calibration jig will be described in detail with reference to FIGS. 2 to 4.

FIG. 3 is a plan view of the calibration jig shown in FIG. 2, and FIG. 4 is a cross-sectional view of the calibration jig shown in FIG. 2.

As shown in FIGS. 2 to 4, the calibration jig 40 is rotatably installed on the upper part of the base 41 and base 42 installed on the floor surface to be worked on, and the tool tip 30 moves inside. It may include a body 43 in which a movement space is formed, and a plate 44 installed on one side of the body 43 to calibrate x, y, and z values.

A magnet 45 may be installed on the base 41 so that the calibration jig 40 can be fixed to the bottom surface of the hull in the field.

The body 43 is formed in a substantially hexahedral shape with an open upper surface, and a movement space 42 having a substantially square cross-section may be formed inside the body 43 so that the tool tip 30 can move.

This body 43 may be rotatably installed on the upper part of the base around an axis (not shown) installed on the lower surface.

On the upper surface of the bottom plate of the body 43, a scale may be displayed at a preset angle, for example, every 5 degrees around the axis, so that the rotation angle of the body 43 can be checked.

The plate 44 extends to one side of the bottom plate of the body 43 to enable calibration of x, y, and z values, and may be installed perpendicular to the side wall of the body 43.

In Figure 4, 'w' is the horizontal and vertical length of the moving space 42, that is, the width of the moving space 42, and 'h' is the height of the moving space 42.

Next, with reference to FIG. 5, a calibration method using a TCP calibration device for a welding robot according to a preferred embodiment of the present invention will be described in detail.

Figure 5 is a process diagram step by step explaining a calibration method using a TCP calibration device for a welding robot according to a preferred embodiment of the present invention.

As shown in FIG. 5, the calibration method using the TCP calibration device of the welding robot according to a preferred embodiment of the present invention is as follows: (a) installing the tool tip 30 on the torch 11 of the welding robot 10 and (10) Rotatably installing the calibration jig 40 on the front hull bottom surface (S10), (b) Calculating the rotation angle of the calibration jig 40 and aligning it in parallel with the welding robot 10 (S12), (c) moving the tooltip 30 in the movement space inside the calibration jig 40 to calibrate the Rx, Ry, and Rz values among the TCP values (S14), and (d) the steps of the calibration jig 40. It includes a step (S16) of calibrating x, y, and z values among TCP values using the side wall and plate 44.

In detail, in step S10 of FIG. 5, the operator installs the tool tip 30 at the tip of the torch 11 of the welding robot 10 and installs the calibration jig 40 on the bottom of the hull.

At this time, the calibration jig 40 can be stably fixed to the bottom of the hull using a magnet 45 installed on the side or bottom of the base 41.

Figures 6 and 7 are exemplary diagrams explaining the process of calculating the rotation angle of the calibration jig.

Figures 6 (a) and (b) show a cross-sectional view and a plan view illustrating the movement of the contact hole 32 in the movement space 42 of the calibration jig 40.

Figure 7 illustrates the process of calculating the rotation angle by moving the contact hole 32 while the calibration jig 40 is rotated.

When the welding robot 10 and the calibration jig 40 are accurately aligned, as shown in (a) and (b) of FIG. 6, the contact hole 32 of the tool tip 30 is positioned horizontally in the movement space 42. and can be moved up to a distance in the y and x axes to measure the vertical length.

At this time, the horizontal and vertical lengths of the moving space 42, that is, the width w=a+4r.

In step S12, the controller (not shown) of the welding robot 10 executes a calibration program stored in memory (not shown) and uses the currently stored TCP value to determine the posture of the tool tip 30, as shown in FIG. Arrange the tooltip (30) so that it is parallel to the z-direction of the robot base.

At this time, the tooltip 30 may not be parallel to the actual z-direction, but the controller uses the value of the state recognized as parallel.

Therefore, the controller controls the contact hole 32 to move to a height that touches the top of the side wall of the calibration jig 40 while maintaining the posture of the tool tip 30.

Then, the controller measures the distances (b, c) by moving the tool tip 30 in the x and y directions of the robot base, respectively.

Next, the controller calculates the rotation angle (t) of the calibration jig using the measured distance.

Here, w = (b+2r)cos t + 2r, w = (c+2r)sin t + 2r.

To summarize, (b+2r)cos t=(c+2r)sin t, so t=tan ^-1 (b+2r)/(c+2r).

Through this process, when the rotation angle of the calibration jig 40 is calculated, the operator rotates the calibration jig 40 by the calculated rotation angle opposite to the direction of rotation, so that the welding robot 10 and the calibration jig 40 are aligned. Arrange it properly.

In step S14, the controller calculates the errors of Rz, Rx, and Ry values among the TCP values and performs sequential calibration.

Figures 8 to 10 are diagrams illustrating the process of calculating the error of Rz value among TCP values.

When the welding robot 10 is at the origin, the TCP is rotated by an angle θ, as shown in FIG. 8. The angle rotated in this way is Rz.

Here, in the welding robot 10, Rz can be set to 0.

Therefore, if the actual rotated angle (θ) is different from Rz, the controller calculates the error (δ) and reflects it in Rz.

Here, θ = Rz + δ.

To this end, as shown in FIG. 9, the controller controls the operation of the welding robot 10 so that the contact hole 32 of the tool tip 30 is located inside the movement space 42 of the calibration jig 40. At this time, the value of the 6th axis that rotates the torch 11 in the Rz direction is 0.

The controller controls the tooltip 30 to rotate in the z-axis direction of the 6-axis coordinate system. Then, only the 6-axis value changes.

As shown in FIG. 10, the controller controls the connection bar 33 of the tool tip 30 to rotate in both directions until it touches both side walls of the calibration jig 40, and then adjusts the rotation angle (α) in both directions at this time. ,β) is measured.

Next, the controller calculates the error using the two-way rotation angles (α, β).

Here, the error is calculated as δ = (β-α)/2, and from the TCP value, Rz can be calculated as θ-δ.

Figures 11 to 13 are diagrams illustrating the process of calculating errors in Ry and Rx values among TCP values.

When the controller controls the posture of the tooltip 30 to be parallel to the z-direction of the robot base using the currently stored TCP value, if there is an error in the Ry value among the TCP values, it may not be parallel.

Therefore, the controller calculates the error (δ) of the Ry value and controls it to be calibrated by reflecting it in the TCP value.

Here, since the error δ is a very small value to measure, the controller drives the welding robot 10 and controls the tool tip 30 to rotate by θ ₀ , as shown in FIG. 11. At this time, the error (δ) can be obtained by finding the difference between the actual rotation angle θ of the tool tip 30 and the target rotation angle θ ₀ to be rotated.

Therefore, the controller drives the welding robot 10 to rotate the tool tip 30 by θ ₀ , and as shown in Figures 12 and 13, uses the touch and relative movement functions of the welding robot 10 to move the contact point ( 32) is controlled so that the center is located at the height of h ₁ . Here, h = h ₁ + h ₂ .

The controller drives the welding robot 10 in the x-direction of the robot base to measure the distance (a), and calculates the actual rotation angle (θ) using the measured distance (a).

이므로, here,

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,

,

,

,

가 된다.

It becomes.

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It becomes.

Here, by substituting A = 4(wr-a+h ₂ ² ) ² , B = 4(r+aw)d, C=d2-4h ₂ ² , 0= AX ² +BX+C .

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가 된다.

It becomes.

Therefore, the controller calculates the error (δ) using the actual rotation angle (θ) and the target rotation angle (θ ₀ ) to be rotated. Here, θ = θ ₀ + δ.

Next, the controller reflects the calculated error (δ) to the Ry value among the TCP values. (Ry of the TCP value = Ry _{existing value} - δ)

Afterwards, the controller calculates the rotation error in the Rx direction in the same way and reflects it in the Rx value.

In step S16, the controller places the tooltip 30 on the calibration jig 40 and the plate 44 and then sequentially calibrates the x, z and y axis directions among the TCP values.

Figures 14 to 16 are diagrams illustrating the process of calibrating the x- and z-axis directions among TCP values, and Figure 17 is a diagram illustrating the process of calibrating the y-axis direction.

The worker installs the calibration jig 40 on the bottom of the hull and moves the welding robot 10 around the calibration jig 40. At this time, the controller stores the initial position (T01) to which the welding robot 10 moved in memory.

Here, the posture of the torch 11 is parallel to the home posture where the values of all axes are 0.

The controller uses the touch function of the welding robot 10 to control the tip of the torch 11 to stop when it touches the side wall of the calibration jig 40, and determines the position of the point P11 in front of the touched torch 11. recognize At this time, the controller can calculate the position of the touched front point (P11) using the rotation angle of each motor of the welding robot 10 and the TCP value.

Then, the controller returns the torch 11 to the initial position (T01), moves it downward and controls it to touch the plate 44, and recognizes the position of the point P12 below the touched torch 11. .

Next, the controller calculates the distance between the initial position (T01) and the touched points (P11, P12) and calculates the coordinate values (x1 , z1) of the initial position (T01) based on the calibration jig (40).

In addition, the controller controls the 5-axis that rotates the torch 11 in the Ry direction to rotate at an arbitrary angle, stores the rotated first rotation position T02 in the memory, and repeats the same touch operation to rotate the torch 11. Calculate the coordinate values (x2, y2) of the location (T02).

Again, the controller controls the 5-axis to rotate at a random angle, stores the rotated second rotation position (T03) in the memory, and repeats the above-mentioned touch operation to obtain the coordinate value of the second rotation position (T03) Calculate x3,y3).

The controller calculates the center of the circle (cx, cy) and the radius (r) of the circle by finding the equation of the circle with the initial position (T01) and the first and second rotation positions (T02, T03).

Next, the controller calculates the TCP value l in the z-axis direction, that is, the z-axis value of TCP when viewed from the 6th axis, using the calculated center of the circle and the initial position (T01). Here, l=c _x -x ₁ .

Then, the controller calculates the TCP value m in the x-axis direction, that is, the x-axis value of TCP when viewed from the 6th axis, using the calculated center of the circle and the initial position (T01). Here, m=z ₁ -c _z .

Meanwhile, when calibrating the y-axis direction, the operator installs the calibration jig 40 on the bottom surface of the hull and moves the welding robot 10 around the calibration jig 40, as shown in FIG. 17. At this time, the controller stores the initial position (T10) of the welding robot 10 in memory.

Here, the posture of the torch 11 is aligned with the y-axis direction of the robot base.

The controller uses the touch function of the welding robot 10 to move the tool tip 30 in the x-axis direction and controls it to stop when the tip of the tool tip 30 touches the side wall of the calibration jig 40, and sets the ) and calculate the distance (a) between the touched point.

Then, the controller returns the tool tip 30 to the initial position (T10) and then controls the tool tip 30 to rotate 180° in the z-axis direction based on the robot base from the initial position (T10).

Here, when the tooltip 30 is aligned in the y-axis direction, the rotation position T11 is the same as the initial position T10.

On the other hand, since the tooltip 30 is in a state before being aligned in the y-axis direction, the controller moves the tooltip 30 in the x-axis direction of the robot base and touches the side wall of the calibration jig 40 to touch the rotation position (T11). Calculate the distance (b) between one point.

Next, the controller calculates the y-axis direction error (δ) using the difference between the two calculated distances (a, b). Here, δ=(a-b)/2.

So, the controller reflects the calculated y-axis direction error (δ) to the y value among the TCP values. (y of the TCP value = y _{existing value} - δ)

Through the process described above, the present invention can precisely calibrate the TCP of a welding robot using the distance the tool tip is moved in the movement space inside the calibration jig having preset horizontal and vertical lengths.

In addition, the present invention can easily calibrate the entire TCP value automatically by installing a calibration jig and tool tip in the field and executing a calibration program in the controller of the welding robot.

Due to this, the present invention can improve workability and maintain good work quality by eliminating repetitive calibration due to errors in TCP when replacing a torch.

Although the invention made by the present inventor has been described in detail according to the above-mentioned embodiments, the present invention is not limited to the above-described embodiments and, of course, can be changed in various ways without departing from the gist of the invention.

The present invention is applied to a technology for precisely calibrating the TCP of a welding robot using the distance the tool tip is moved in the movement space inside the calibration jig having preset horizontal and vertical lengths.

10: Welding robot 11: Torch
20: TCP calibration device
30: Tooltip 31: Body
32: contact part 33: connecting bar
40: Calibration jig 41: Base
42: moving space 43: body
44: plate 45: magnet
46: graduation

Claims (11)

Tool tip installed on the tip of the torch of the welding robot
For TCP calibration, a movement space within which the tool tip moves is formed and a calibration jig is rotatably installed on the floor,
A TCP calibration device for a welding robot, characterized in that the controller of the welding robot calibrates the entire TCP value using the distance the tool tip moves within the movement space and the horizontal and vertical lengths and heights of the movement space. The method of claim 1, wherein the tooltip is
A body coupled to the tip of the torch,
A contact hole formed in a spherical shape and
Includes a connecting bar connecting the body and the contact port,
A TCP calibration device for a welding robot, characterized in that the contact hole moves in the According to paragraph 1,
The calibration jig includes a base installed on the floor,
A body rotatably installed on the upper part of the base and a moving space inside which the tool tip moves is formed;
A TCP calibration device for a welding robot, comprising a plate extending on one side of the body to calibrate x-, y-, and z-axis values among the TCP values. According to paragraph 3,
A magnet is installed on the base to secure the calibration jig to the floor,
The moving space is formed in a square cross-section,
The body is rotatably installed on the upper part of the base about an axis installed on the lower surface,
A TCP calibration device for a welding robot, characterized in that a scale is displayed on the upper surface of the bottom plate of the body at each preset angle around the axis so that the rotation angle of the body can be checked. In the calibration method using the TCP calibration device of a welding robot according to any one of claims 1 to 4,
(a) Installing a tool tip on the torch of a welding robot and rotatably installing a calibration jig on the floor,
(b) calculating the rotation angle of the calibration jig and aligning it in parallel with the welding robot,
(c) moving the tooltip in the movement space inside the calibration jig to calibrate Rx, Ry, and Rz values among TCP values; and
(d) A calibration method using a TCP calibration device for a welding robot, comprising the step of calibrating x, y, and z values among TCP values using the side wall and plate of the calibration jig. The method of claim 5, wherein step (b) is
(b1) executing a calibration program in the controller of the welding robot to place the tooltip so that its posture is parallel to the z-direction of the robot base using the currently stored TCP value,
(b2) controlling the contact port of the tool tip to move to a height that touches the top of the side wall of the calibration jig while maintaining the posture of the tool tip,
(b3) measuring the distance by moving the tooltip in the x and y directions of the robot base, respectively, and
(b4) calculating the rotation angle of the calibration jig using the distance measured in step (b3) and rotating the calibration jig in the opposite direction by the calculated rotation angle to align it with the welding robot. A calibration method using a TCP calibration device for a welding robot, characterized in that: The method of claim 6, wherein step (c) is
(c1) driving the welding robot so that the contact port of the tool tip is located inside the moving space of the calibration jig,
(c2) rotating the tooltip in the z-axis direction of the 6-axis coordinate system,
(c3) measuring the rotation angle by rotating the connection bar of the tool tip in both directions until it touches both side walls of the calibration jig; and
(c4) A calibration method using a TCP calibration device for a welding robot, comprising the step of calculating an error using the measured two-way rotation angle and reflecting it from the TCP value to the Rz value. The method of claim 7, wherein step (c) is
(c5) driving the welding robot to control the tool tip to rotate by the target rotation angle,
(c6) controlling the center of the contact hole to be located at the first height using the touch and relative movement functions of the welding robot,
(c7) measuring the distance by driving the welding robot in the x-direction of the robot base and calculating the actual rotation angle using the measured distance;
(c8) A TCP calibration device for a welding robot, further comprising calculating an error using the calculated actual rotation angle and the target rotation angle, and calibrating the calculated error by reflecting it on the Ry value among the TCP values. Calibration method using . According to clause 8,
Step (c) further includes the step (c9) of performing steps (c5) to (c8) in the same manner in the y direction of the robot base and calibrating the calculated error by reflecting it in the Rx value among the TCP values. A calibration method using a TCP calibration device for a welding robot, characterized in that: The method of claim 7, wherein step (d) is
(d1) installing the calibration jig on the bottom of the hull and moving the welding robot around the calibration jig while maintaining the torch parallel to the home position where all axis values are 0,
(d2) using the touch function of the welding robot to control the tip of the torch to stop when it touches the side wall of the calibration jig, and recognizing the position of the touched point in front of the torch,
(d3) Returning the torch to its initial position before performing step (d2) and then moving it downward to recognize the position of the point on the lower part of the torch that touched the plate extended to one side of the calibration jig. ,
(d4) calculating the distance between the initial position and the touched points and calculating the coordinate value of the initial position based on the calibration jig,
(d5) controlling the 5-axis that rotates the torch in the Ry direction to rotate at a random angle and calculating the coordinate values of the first and second rotation positions rotated at different angles;
(d6) Find the equation of the circle with the initial position and the first and second rotation positions, calculate the center of the circle and the radius of the circle, and use the calculated center of the circle and the initial position to determine z and x values among the TCP values. A calibration method using a TCP calibration device for a welding robot, comprising the step of calibrating. The method of claim 10, wherein step (d) is
(d7) With the torch aligned with the y-axis direction of the robot base, the tooltip is moved in the calculating the distance,
(d8) returning the tool tip to the initial position and rotating it 180° in the z-axis direction based on the robot base from the initial position,
(d9) moving the tooltip in the x-axis direction of the robot base and touching the side wall of the calibration jig to calculate the distance between the rotation position and the touched point;
(d10) TCP of a welding robot, further comprising calculating a y-axis direction error using the difference between the two calculated distances, and calibrating the calculated y-axis direction error by reflecting it in the y value among the TCP values. Calibration method using a calibration device.

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