JP2020124728A - Laser beam machining robot and tool coordinate system setting method - Google Patents

Abstract

To provide a method for accurately positioning a tool position of a laser beam machining robot at a machining point.SOLUTION: A laser beam machining robot includes: a robot arm 2b; a laser beam machining head 3 which is mounted at a tip of the arm 2b; a detection section 4 which detects laser beam L regularly reflected along an emitting optical axis A from a reflection surface 10a to the head 3; and a control section. The reflection surface 10a is a spherical surface or a polyhedron surface which has a prescribed reference point P as a center and regularly reflects laser beam L directed to the reference point P along the emitting optical axis A. The control section aligns the head 3 with a position where laser beam L regularly reflected along the emitting optical axis A is detected by the detection section 4 by operating the arm 2b, calculates the direction of the emitting optical axis A on the basis of the position and posture of the tip of the arm 2b in the aligned state of the head 3 and the position of the reference point P, and sets an axis of a coordinate system of the head 3 on the basis of the direction of the emitting optical axis A.SELECTED DRAWING: Figure 2

Description

The present invention relates to a laser processing robot and a tool coordinate system setting method.

2. Description of the Related Art Conventionally, a robot that performs processing such as welding or cutting on a work with a laser beam is known (for example, see Patent Document 1). In Patent Document 1, the laser irradiation device is moved to a predetermined command position by the operation of the robot, the actual position of the laser irradiation position is measured, and the laser is calculated based on the deviation between the command position of the laser irradiation position and the actual position. It is described that the irradiation position is corrected.
Further, a method of aligning a probe with a target position using a light-reflecting sphere and laser light has been proposed (for example, refer to Patent Document 2).

JP, 2008-024011, A Japanese Patent No. 4664412

As a method of setting one point on the tool of the robot to TCP (tool center point), 6-point teaching using a jig is generally used. In the case of a machining tool, in 6-point teaching, the reference point of the jig is placed at a predetermined position with respect to the robot, and the machining point of the tool (for example, the tip of the tool) is made to coincide with the reference point by the operation of the robot arm. To be

In the case of remote welding in which the work is irradiated with laser light from a position distant from the work, it is difficult to use the 6-point teaching because there is no object such as the tip of the tool at the processing point.
By attaching a member such as a rod to the laser processing head of the robot and arranging the tip of the member at the processing point, it is possible to set the TCP by teaching six points. However, in this case, it is difficult to set the TCP so as to exactly match the processing point due to the influence of an error in mounting the member on the laser processing head.
The design value of the position of the processing point may be set to TCP. However, since there is an error between the design value of the position of the processing point and the actual position of the processing point, it is difficult to set the TCP so as to exactly match the processing point in this case as well.

One aspect of the present disclosure includes a robot arm, a laser processing head that is attached to a tip of the robot arm and emits a laser beam, and a reflection surface that is provided on the laser processing head and is disposed outside the laser processing head. To the laser processing head, a detection unit that detects the laser light specularly reflected along the emission optical axis of the laser light, a control unit that controls the robot arm and sets the coordinate system of the laser processing head, The reflecting surface is a spherical surface or a polyhedron surface centered on a predetermined reference point, and specularly reflects the laser light toward the predetermined reference point along an emission optical axis of the laser light, The unit positions the laser processing head at a position where the laser beam specularly reflected along the emission optical axis is detected by the detection unit by operating the robot arm, and the laser processing head is positioned. The direction of the emission optical axis is calculated based on the position and orientation of the tip of the robot arm in the aligned state and the position of the predetermined reference point, and based on the calculated direction of the emission optical axis. Is a laser processing robot for setting the axis of the coordinate system of the laser processing head.

It is the whole laser processing robot lineblock diagram concerning one embodiment. It is a figure explaining the relationship between the emission optical axis of laser light and the reflection optical axis of the laser light specularly reflected by the laser processing head from the hemispherical reflecting surface. It is a front view of the detection surface of a detection part, and is a figure explaining the position of the spot of the reflected laser light on a detection surface. 6 is a flowchart illustrating a tool coordinate system setting method according to an embodiment. 6 is a flowchart illustrating a tool coordinate system setting method according to an embodiment. It is a figure explaining operation|movement of the robot arm in a TCP setting process. It is a figure which shows one structural example of the scanning part provided in a laser processing head.

The laser processing robot 1 according to the embodiment will be described below with reference to the drawings.
As shown in FIG. 1, the laser processing robot 1 arranges a focus F of the laser light L on the work W and performs remote processing such as welding or cutting on the work W by the laser light L. The laser processing robot 1 includes a robot body 2 having a base 2a and an articulated robot arm 2b, a laser processing head 3 attached to the tip of the robot arm 2b for emitting a laser beam L, and a laser processing head 3 provided with a laser. A detection unit 4 for detecting the laser light L reflected by the processing head 3, and a controller 5 connected to the robot body 2, the laser processing head 3 and the detection unit 4 are provided.

The robot body 2 is, for example, a 6-axis vertical articulated robot. The robot body 2 may be another type of robot generally used for laser processing. The base 2a is fixed on the floor surface and supports the robot arm 2b. The robot body 2 includes a servo motor (not shown) for driving each joint of the robot arm 2b, and an encoder (not shown) for detecting a rotation angle of each joint.

The laser processing head 3 is connected to a laser light source (not shown) by a cable 6 and emits the laser light L supplied from the laser light source via the cable 6. The laser light L is focused on a focal point F outside the laser processing head 3 by a lens (not shown) in the laser processing head 3. The focal point F is a processing point where the work W is processed by the laser light L. The position and orientation of the laser processing head 3 are changed by the movement of the joint of the robot arm 2b, and the position of the focus F is three-dimensionally changed accordingly.

The detection unit 4 is, for example, a camera or a photodetector, and has a two-dimensional detection surface 4a. As shown in FIG. 2, the laser light L specularly reflected from the reflection surface 10a to the laser processing head 3 outside the laser processing head 3 (hereinafter referred to as the reflected laser light L') is incident on the detection surface 4a. .. For example, a partial reflection mirror 3a such as a half mirror is arranged on the optical path of the laser light L in the laser processing head 3. Part of the reflected laser light L′ returning to the optical path is separated from the optical path by the partial reflection mirror 3a and is incident on the detection surface 4a.

The detection surface 4a is arranged such that the optical axis (reflected optical axis) A′ of the reflected laser light L′ specularly reflected along the emission optical axis A by the reflection surface 10a is located at the center of the detection surface 4a. There is. The emission optical axis A is the optical axis of the laser light L emitted from the laser processing head 3 to the reflecting surface 10a. The reflected laser light L′ having the reflected optical axis A′ that is deviated from the emission optical axis A does not enter the detection surface 4 a, or enters the position deviated from the center of the detection surface 4 a. In FIG. 3, a solid circle indicates a reflected laser light L′ that is specularly reflected along the emission optical axis A′ or a strong light spot near the emission optical axis A′, and a two-dot chain line circle indicates the emission light. It shows the reflected laser light L′ specularly reflected along the reflected optical axis A′ deviated from the axis A′ or a strong light spot near the emission optical axis A′. When the center of the spot coincides with the center of the detection surface 4a, the detection unit 4 detects the reflected laser light L'which is specularly reflected along the emission optical axis A and also detects the diameter of the spot on the detection surface 4a. To do.

The control device 5 includes a control unit 5a having a processor and a storage unit 5b having a RAM, a ROM, a non-volatile storage, and the like.
The storage unit 5b stores a processing program for processing the work W with the laser light L. The control unit 5a causes the robot arm 2b and the laser processing head 3 to perform an operation based on the processing program by transmitting a control command to each servo motor of the robot arm 2b and the laser processing head 3 according to the processing program.

In executing the processing program, the control unit 5a controls the position of the focus F by controlling the operation of the robot arm 2b based on the world coordinate system Σw of the robot body 2 and the tool coordinate system Σt of the laser processing head 3. ..
The world coordinate system Σw is a coordinate system fixed with respect to the base 2a.
The tool coordinate system Σt is a coordinate system that is fixed with respect to the laser processing head 3 and is set with reference to the emission optical axis A of the laser light L and the focus F. For example, the tool coordinate system Σt is a three-dimensional orthogonal coordinate system, the Z axis of the tool coordinate system Σt is set parallel to the emission optical axis A of the laser light L, and the origin of the tool coordinate system Σt is set to the focus F. R.

The tool coordinate system Σt is set, for example, when the robot is installed in a factory or when the laser processing head 3 is replaced. The storage unit 5b stores a tool coordinate system setting program for setting the tool coordinate system Σt. The control unit 5a causes the robot arm 2b, the laser processing head 3, and the detection unit 4 to execute an operation for acquiring information necessary for setting the tool coordinate system Σt according to the tool coordinate system setting program, and acquires the acquired information. Based on this, the tool coordinate system Σt is set.

Next, a tool coordinate system setting operation (tool coordinate system setting method) based on the tool coordinate system setting program will be described.
A hemispherical reflecting member 10 is used for the tool coordinate system setting work, as shown in FIG. The reflecting member 10 has a convex hemispherical reflecting surface 10a and a circular bottom surface 10b connecting the ends of the reflecting surface 10a. The reflecting surface 10a is a mirror that regularly reflects the laser light L. The reflecting surface 10a has a curvature center P arranged at the center of the bottom surface 10b and a constant curvature. At an arbitrary point on the reflecting surface 10a, the laser light L directed to the center of curvature P is regularly reflected along the emission optical axis A. The center of curvature P is used as a reference point for setting the tool coordinate system Σt.

The reflecting member 10 is arranged within the movement range of the robot arm 2b, and the reference point P is positioned at a predetermined position coordinate in the world coordinate system Σw.
The reflecting member 10 is arranged at an arbitrary position within the operation range of the robot arm 2b, the position coordinate of the reference point P in the world coordinate system Σw is input to the control device 5 by the user, and the input position coordinate is the tool coordinate system. It may be configured to be used in a setting program.

The tool coordinate system setting operation includes a Z-axis setting step for setting the Z-axis of the tool coordinate system Σt shown in FIG. 4 and a TCP setting step for setting TCP shown in FIG.
As shown in FIG. 4, in the Z-axis setting step, the control unit 5a operates the robot arm 2b to detect the reflected laser light L′ specularly reflected along the emission optical axis A by the detection unit 4. The laser processing head 3 is aligned to the position (steps SA1 to SA4), and the position and orientation of the tip of the robot arm 2b in the state where the laser processing head 3 is aligned are calculated (step SA5). The direction of the emission optical axis A with respect to the tip of the robot arm 2b is calculated based on the position and orientation of the tip of the robot arm 2b and the position of the reference point P (step SA6), and the direction of the calculated emission optical axis A is calculated. Based on this, the Z axis is set (step SA7).

Specifically, as shown in FIG. 2, the control section 5a operates the robot arm 2b to move the laser processing head 3 to the reference point P so that the laser light L substantially goes to the reference point P. Positioning is performed (step SA1). The position and orientation of the laser processing head 3 at this time are set based on the design value of the laser processing head 3.

Next, the control unit 5a causes the laser beam L to be emitted from the laser processing head 3 (step SA2), and whether or not the reflected laser beam L′ that is regularly reflected along the emission optical axis A is detected by the detection unit 4. It is determined (step SA3).
When the laser light L is accurately oriented in the direction of the reference point P (that is, when the reference point P is located on the extension line of the emission optical axis A), the laser light L is emitted by the reflecting surface 10a. It is specularly reflected along A. When the reflected laser light L′ specularly reflected along the emission optical axis A is detected by the detector 4 (YES in step SA3), the controller 5a proceeds to the next step SA5.

On the other hand, when the laser light L does not accurately point in the direction of the reference point P, the laser light L is specularly reflected by the reflection surface 10a along the reflection optical axis A'shifted from the emission optical axis A. When the reflected laser light L′ specularly reflected along the emission optical axis A is not detected by the detection unit 4 (NO in step SA3), the control unit 5a operates the robot arm 2b to move the laser processing head 3a. The position and orientation are adjusted (step SA4), and steps SA2 and SA3 are executed again. The control unit 5a repeats steps SA4, SA2, and SA3 until the detection unit 4 detects the reflected laser light L'which is specularly reflected along the emission optical axis A.

Next, the control unit 5a acquires the rotation angle of each joint of the robot arm 2b from the encoder, and calculates the position and orientation of the tip of the robot arm 2b in the world coordinate system Σw from the rotation angle of each joint (step SA5). ). The position of the tip of the robot arm 2b is, for example, the center position of the tip surface of the robot arm 2b.

Next, the control unit 5a calculates the reference position of the laser processing head 3 from the calculated position and orientation of the tip of the robot arm 2b, and determines the reference position from the reference position of the laser processing head 3 and the position of the reference point P with respect to the reference position. The direction of the emission optical axis A is calculated (step SA6). The reference position of the laser processing head 3 is a position of a representative point on the laser processing head 3 fixed to the tip of the robot arm 2b.
Next, the control unit 5a sets the Z axis of the tool coordinate system Σt in a direction parallel to the direction of the emission optical axis A (step SA7). For example, the control unit 5a sets the Z axis on the emission optical axis A.

The control unit 5a executes the TCP setting process subsequent to the Z-axis setting process.
As shown in FIG. 5, in the TCP setting step, the control unit 5a operates the robot arm 2b, so that the reflected laser light L′ is regularly reflected along the emission optical axis A detected by the detection unit 4. The laser processing head 3 is aligned to the position where the luminous flux diameter is minimized (steps SB1 to SB4), and the position and orientation of the tip of the robot arm 2b in the state where the laser processing head 3 is aligned are calculated (step SB1). SB5), steps SB1 to SB5 are repeated with different postures of the robot arm 2b (step SB6), and the calculated position and posture of the tip of the robot arm 2b, the position of the reference point P, and the reference point P to the reflecting surface 10a. The position of the focus F with respect to the tip of the robot arm 2b is calculated based on the distance (step SB8), and TCP is set based on the calculated position of the focus F (step SB9).

Specifically, the control unit 5a positions the laser processing head 3 by operating the robot arm 2b so that the laser light L is substantially directed to the reference point P and the focus F is substantially coincident with the reflection surface 10a. Yes (step SB1). The position and orientation of the laser processing head 3 at this time are set based on the design value of the laser processing head 3.
Next, the controller 5a causes the laser processing head 3 to emit the laser beam L (step SB2). Then, the control unit 5a detects the reflected laser light L′ which is specularly reflected along the emission optical axis A by the detection unit 4 and has a minimum luminous flux diameter of the reflected laser light L′ detected by the detection unit 4. Or not (step SB3).

As shown in FIG. 6, when the laser light L accurately points in the direction of the reference point P and the focal point F coincides with the reflecting surface 10a, the luminous flux diameter of the reflected laser light L′ becomes the minimum and the detection is performed. The diameter of the spot formed in the center of the surface 4a is the smallest. The control unit 5a detects the reflected laser light L'which is specularly reflected along the emission optical axis A by the detection unit 4 and has the smallest spot diameter on the detection surface 4a (YES in step SB3). ), and proceeds to the next Step SB5. The determination as to whether or not the spot diameter is the smallest is made by, for example, comparison with a predetermined threshold value set based on the minimum value of the spot diameter measured in advance.

On the other hand, if the reflected laser light L′ specularly reflected along the emission optical axis A is not detected by the detection unit 4 or the spot diameter on the detection surface 4a is not the minimum (step SB3). No), the position and orientation of the laser processing head 3 is adjusted by operating the robot arm 2b (step SB4), and steps SB2 and SB3 are executed again. The control unit 5a performs steps SB4 and SB2 until the reflected laser light L′ specularly reflected along the emission optical axis A is detected by the detection unit 4 and the spot diameter of the reflected laser light L′ becomes the minimum. , SB3 are repeated.

Next, the control unit 5a acquires the rotation angle of each joint of the robot arm 2b from the encoder, and calculates the position and orientation of the tip of the robot arm 2b in the world coordinate system Σw from the rotation angle of each joint (step SB5). ).
Next, as shown in FIG. 6, the controller 5a operates the robot arm 2b to cause the laser light L to substantially go to the reference point P and the focus F to substantially coincide with the reflecting surface 10a. The laser processing head 3 is positioned at the position (step SB7). As a result, the posture of the robot arm 2b is changed. Then, the control unit 5a repeats steps SB2 to SB5.
The controller 5a executes steps SB2 to SB5 in at least two postures of the robot arm 2b (steps SB6 and SB7), and calculates the position and posture of the tip of the robot arm 2b in at least two postures.

Next, the control unit 5a calculates the position of the focus F in each posture of the robot arm 2b. Specifically, the controller 5a controls the position and posture of the tip of the robot arm 2b, the position of the reference point P, and the distance from the reference point P to the focal point F on the reflection surface 10a (that is, the radius of the reflection surface 10a). ) And the relative position of the focus F with respect to the reference position of the laser processing head 3 in the world coordinate system Σw. Next, the control unit 5a calculates the position of the focus F in the tool coordinate system Σt from the relative position of the focus F in the two postures (step SB8).
Next, the control unit 5a sets the origin of the tool coordinate system Σt and TCP at the calculated position of the focal point F (step SB9). For example, the control unit 5a sets the origin of the tool coordinate system Σt and TCP at the focus F.

As described above, according to the present embodiment, in setting the tool coordinate system Σt, the laser beam L emitted from the laser processing head 3, the convex spherical reflecting surface 10a having the reference point P at the center of curvature, and the reflection The detection unit 4 that detects the reflected laser light L′ that is specularly reflected from the surface 10 a is used. Then, based on the position of the spot of the reflected laser light L'on the detection surface 4a, the direction of the laser light L can be accurately aligned with the reference point P so that the laser light L faces the reference point P. Accordingly, the direction of the emission optical axis A can be accurately calculated, and the Z axis of the tool coordinate system Σt can be accurately set so that the Z axis is parallel to the emission optical axis A.

Further, based on the position and diameter of the spot of the reflected laser light L′ on the detection surface 4a, the focal point F is aligned with the reference point P so that the focus F coincides with the reflection surface 10a with the laser light L facing the reference point P. Therefore, the position of the focal point F can be accurately adjusted. As a result, the position of the focus F can be accurately calculated, and the TCP can be accurately set so that the TCP matches the focus F that is the processing point.

In the above embodiment, whether or not the focus F coincides with the reflecting surface 10a in the direction along the emission optical axis A is determined based on the diameter of the spot on the detection surface 4a, but instead of this, You may judge based on the brightness of a spot. In this case, when the brightness of the spot at the center of the detection surface 4a is maximized, it can be determined that the focus F coincides with the reflection surface 10a.

In the above embodiment, the Z-axis setting step is performed separately from the TCP setting step, but the Z-axis setting step may be performed within the TCP setting step. That is, in steps SB<b>1 to SB<b>4, the laser processing head 3 is aligned with the position at which the reflected laser light L′ specularly reflected along the emission optical axis A is detected by the detection unit 4. Therefore, after the step SB5, the Z-axis direction may be calculated using the position and orientation of the tip of the robot arm 2b calculated in the step SB5.

In the above-described embodiment, the laser light L used for setting the tool coordinate system Σt may be the laser light used for processing the workpiece W or may be a laser light different from the processing laser light. Good. For example, when the processing laser light is invisible light such as infrared light, the visible laser light may be used for setting the tool coordinate system Σt. The setting laser light L is guided along the same optical path as the processing laser light so as to be coaxial with the processing laser light.
The position of the focal point of the laser light changes in the direction along the emission optical axis according to the wavelength of the laser light. Therefore, when the laser beam L having a wavelength different from the wavelength of the laser beam for processing is used for setting the tool coordinate system Σt, the focus of the laser beam for processing is taken into consideration in step SB8 in consideration of the difference in wavelength. The position is calculated.

In the above embodiment, the laser processing head 3 may further include the scanning unit 7 that swings the laser light L around the swing axis that intersects the emission optical axis A.
FIG. 7 shows a configuration example of the scanning unit 7 in the laser processing head 3. The scanning unit 7 is a galvano scanner having two galvano mirrors 7a and 7b. The swing axes S1 and S2 of the two Galvano mirrors 7a and 7b are arranged at mutually twisted positions, and the laser light L swings in two directions according to the swing of the two Galvano mirrors 7a and 7b. That is, the angle of the emission optical axis A of the laser light L changes by an angle according to the swing angle of the Galvano mirrors 7a and 7b.
Reference numerals 7c and 7d are motors for swinging the Galvano mirrors 7a and 7b around the swing shafts S1 and S2, respectively. Reference numeral 7e is a lens that focuses the laser light L.

The scanning unit 7 can control the direction of the emission optical axis A of the laser light L with high accuracy as compared with the operation of the robot arm 2b. Therefore, the direction of the laser light L with respect to the reference point P may be adjusted by the operation of the scanning unit 7 in addition to the operation of the robot arm 2b.
Specifically, with the galvano mirrors 7a and 7b arranged at a reference angle (for example, 0°), the laser processing head 3 is positioned so that the laser light L substantially moves toward the reference point P by the operation of the robot arm 2b. To be done. Subsequently, the laser beam L is swung by the swing of the Galvano mirrors 7a and 7b, and the swing angle of the laser beam L is set to the angle at which the reflected laser beam L′ along the emission optical axis A is detected by the detection unit 4. Adjusted.

In this case, the control unit 5a calculates the adjustment amount of the swing angle of the laser light L from the swing angles of the Galvano mirrors 7a and 7b, and the scanning unit 7 does not adjust the swing angle of the laser light L ( A state in which the laser processing head 3 is aligned with a position where the laser beam L specularly reflected along the emission optical axis A is detected by the detection unit 4 in a state where the Galvano mirrors 7a and 7b are arranged at the reference angle). The position and the posture of the tip of the robot arm 2b at are calculated.

Although a hemispherical mirror is used as the reflecting surface 10a in the above embodiment, the reflecting surface 10a having another shape may be used.
For example, the reflecting surface 10a may be a partial spherical surface having a solid angle smaller than that of the hemispherical surface, and the curvature center P serving as a reference point may exist outside the reflecting member 10.
Alternatively, the reflecting surface 10a may be a polyhedral surface having a plurality of flat surfaces centered on the reference point P. In this case, the laser beam L traveling toward the reference point P is regularly reflected along the emission optical axis A at one specific point on each flat surface. The reflecting surface 10a may be an arbitrary curved surface having such a specific point.

In the above embodiment, the position of the focus F in the Z-axis direction in each posture of the robot arm 2b is calculated, but instead of this, the distance from the laser processing head 3 to the focus F in the Z-axis direction. May be measured by other means. For example, the distance to the reflecting surface 10a may be measured by the laser distance measuring device provided in the laser processing head 3 in a state where the focal point F coincides with the reflecting surface 10a.

1 Laser processing robot 2b Robot arm 3 Laser processing head 4 Detection part 4a Detection surface 5a Control part 7 Scanning part, Galvano scanner 10a Reflective surface A Emission optical axis A'Reflected optical axis F focus, Processing point L Laser light L'Reflected laser Light P Reference point, center of curvature Σt Tool coordinate system

Claims (8)

A robot arm,
A laser processing head attached to the tip of the robot arm for emitting laser light;
A detection unit provided on the laser processing head and detecting a laser beam specularly reflected along an emission optical axis of the laser beam from a reflection surface arranged outside the laser processing head to the laser processing head;
A control unit that controls the robot arm and sets the coordinate system of the laser processing head,
The reflection surface is a spherical surface or a polyhedron surface having a predetermined reference point as a center, and specularly reflects the laser light toward the predetermined reference point along an emission optical axis of the laser light,
The control unit is
By operating the robot arm, the laser processing head is aligned to a position where the laser light specularly reflected along the emission optical axis is detected by the detection unit,
Calculating the direction of the emission optical axis based on the position and orientation of the tip of the robot arm in a state where the laser processing head is aligned, and the position of the predetermined reference point;
A laser processing robot that sets an axis of a coordinate system of the laser processing head based on the calculated direction of the emission optical axis. The detection unit has a two-dimensional detection surface on which the laser light specularly reflected along the emission optical axis is incident, and the detection surface of the laser light specularly reflected along the emission optical axis. The laser processing robot according to claim 1, wherein the optical axis is arranged so as to be located at the center of the detection surface. The laser processing head emits the laser light that converges to a focal point outside the laser processing head,
The detection unit detects the luminous flux diameter or the brightness of the laser light regularly reflected along the emission optical axis,
The control unit,
By operating the robot arm, the laser processing head is aligned at a position where the luminous flux diameter of the laser light specularly reflected along the emission optical axis detected by the detection unit is minimum or maximum brightness. Then
The position and orientation of the tip of the robot arm in a state where the laser processing head is aligned, the position of the predetermined reference point, and the distance from the predetermined reference point to the reflecting surface, Calculate the position of the focus with respect to the tip of the robot arm,
The laser processing robot according to claim 1, wherein a tool center point of the laser processing head is set based on the calculated position of the focus. The laser processing robot according to claim 1, wherein the laser processing head includes a scanning unit that swings the laser light around a swing axis that intersects the emission optical axis. The control unit,
After the positioning of the laser processing head by the operation of the robot arm, the scanning section is operated to specularly reflect the swing angle of the laser beam around the swing axis along the emission optical axis. Adjust the laser light to the angle detected by the detector,
The direction of the emission optical axis based on the position and posture of the tip of the robot arm in a state where the laser processing head is aligned, the position of the predetermined reference point, and the swing angle of the laser beam. The laser processing robot according to claim 4, wherein: A method for setting a tool coordinate system of a laser processing head attached to a tip of a robot arm using a reflecting surface, wherein the reflecting surface is arranged outside the laser processing head and is centered on a predetermined reference point. Is a spherical surface or a polyhedral surface, and specularly reflects the laser light toward the predetermined reference point along the emission optical axis of the laser light,
Positioning the laser processing head at a position where the laser light is specularly reflected along the emission optical axis by the reflecting surface by operating the robot arm;
Calculating the direction of the emission optical axis based on the position and orientation of the tip of the robot arm in a state where the laser processing head is aligned, and the position of the predetermined reference point;
Setting a coordinate system axis of the laser processing head based on the calculated direction of the emission optical axis. The laser processing head emits the laser light that converges to a focal point outside the laser processing head,
Aligning the laser processing head to a position where the beam diameter of the laser light specularly reflected along the emission optical axis is minimum or maximum by operating the robot arm,
Based on the position and posture of the tip of the robot arm in a state where the laser processing head is aligned, the position of the predetermined reference point, and the distance from the predetermined reference point to the reflecting surface, Calculating the position of the focal point relative to the tip of the robot arm;
7. The tool coordinate system setting method according to claim 6, further comprising: setting a tool center point based on the calculated position of the focus. The tool coordinate system setting method according to claim 6 or 7, wherein the reflecting surface is a convex spherical surface having a constant curvature and having the predetermined reference point as a center of curvature.

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