TEACHING POINT GENERATION DEVICE FOR GENERATING TEACHING POINTS BASED ON SENSOR OUTPUT, ROBOT CONTROL DEVICE, AND TEACHING POINT GENERATION METHOD

Abstract

In the present invention, a robot control device comprises: a search point calculation unit that calculates the position of a search point on the basis of at least one teaching point; and a command unit that drives a robot such that the position of the robot corresponds to the search point. The robot control device comprises a teaching point setting unit that sets the positions of the teaching points on the basis of a working position detected by a laser sensor. The robot control device sets the positions of a plurality of teaching points arranged along a work line by repeating: the calculation of the position of the search point by the search point calculation unit; the driving of the robot by the command unit; and the setting of the positions of the teaching points by the teaching point setting unit.

Description

[Technical field]

[0001] The present invention relates to a teaching point generating device that generates teaching points based on the output of a sensor. , a robot control device, Also, the present invention relates to a teaching point generating method. [Background technology]

[0002] The robot device includes a robot, a work tool attached to the robot, and a control device that controls the robot. The control device drives the robot and the work tool based on a work program. An operator can teach the robot teaching points in advance to determine the position and posture of the robot during the work. The work program is created based on the positions of the teaching points.

[0003] The positions of the teaching points can have a significant effect on the quality of work performed by a robot device. For example, in a robot device performing arc welding, the robot moves a welding torch along a work path determined based on the teaching points. If the work path deviates from a desired path, the welding position will deviate.

[0004] In order to correct such a deviation in the welding position, a control is known in which a laser sensor is placed on the welding torch and the work path is corrected while welding is being performed. For example, the work position where welding should be performed is detected by the laser sensor while welding is being performed. It is known that the control device corrects the work path determined by the work program based on the work position detected by the laser sensor (for example, JP-A-9-277045 and JP-A-8-166813).

[0005] Also, a control method is known in which a work path is generated in advance by specifying a start point and an end point, and the position of the robot is advanced along the work path while the position where welding is to be performed detected by a laser sensor is set as a teaching point (for example, JP-A-7-104831). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 9-277045 [Patent Document 2] Japanese Patent Application Publication No. 8-166813 [Patent Document 3] Japanese Patent Application Publication No. 7-104831 Summary of the Invention [Problem to be solved by the invention]

[0007] In order for a robot device to perform work with high quality, it is preferable to set teaching points accurately. For example, the teaching points defined in the work program are set by an operator operating a teaching operation panel to change the position and posture of the robot so that the work tool is in the desired position and posture. Then, when the position and posture of the robot are in the desired position and posture, a teaching operation can be performed to set the teaching points.

[0008] However, there are cases where it is difficult to perform this teaching operation. For example, when manually adjusting the position and posture of a robot to perform arc welding, the distance between the weld line to be welded and the tip point of the welding torch becomes short. An operator may have to adjust the position of the tip point of the welding torch with an accuracy of 1 mm or less. Since many teaching points must be set along the weld line, the work time increases. Furthermore, the operator needs to have high skill. In particular, when the weld line includes a curve, many teaching points need to be generated in the range where the direction of the weld line changes. There is a problem that the operator needs a lot of time to generate the teaching points.

[0009] In addition, by attaching a laser sensor to the robot device, the work path for performing the welding can be corrected based on the output of the laser sensor while performing the actual welding work. However, in order to perform this control, it is necessary to set teaching points in advance. In other words, it is necessary to determine teaching points that serve as references for the work path in advance. [Means for solving the problem]

[0010] A first teaching point generating device of the present disclosure generates teaching points for a robot device including a robot and a work tool. Supported by robots, The robot device includes a sensor for detecting a work position on a work line where the robot device performs work on a workpiece. The teaching point generation device includes a search point calculation unit that calculates the position of a search point for determining a next teaching point along the work line based on at least one teaching point, and a command unit that drives the robot so that the robot's position moves to a movement point corresponding to the search point. The teaching point generation device includes a teaching point setting unit that sets the position of the teaching point based on a work position detected by the sensor after the robot's position moves to the movement point. The teaching point generation device sets the positions of multiple teaching points along the work line by repeating setting control including calculation of the position of the search point by the search point calculation unit, driving of the robot by the command unit, and setting of the position of the teaching point by the teaching point setting unit. If the sensor cannot detect the work position after the robot's position moves to the movement point, the command unit drives the robot to rotate the sensor around a predetermined rotation axis, and the sensor detects the work position at the position after the rotation. A second teaching point generating device of the present disclosure generates teaching points for a robot device including a robot and a work tool. Supported by robots,The robot device includes a sensor for detecting a work position on a work line where the robot device performs work on a workpiece. The teaching point generation device includes a search point calculation unit that calculates the position of a search point for determining a next teaching point along the work line based on at least one teaching point, and a command unit that drives the robot so that the position of the robot moves to a movement point corresponding to the search point. The teaching point generation device includes a teaching point setting unit that sets the position of the teaching point based on the work position detected by the sensor after the robot moves to the movement point. The teaching point generation device sets the positions of multiple teaching points along the work line by repeating setting control including calculation of the position of the search point by the search point calculation unit, driving of the robot by the command unit, and setting of the position of the teaching point by the teaching point setting unit. If the sensor cannot detect the work position after the robot's position has moved to the movement point, the search point calculation unit calculates the position of the revised search point by making the distance from the teaching point to the search point shorter than the distance from the current teaching point to the search point, the command unit drives the robot so that the robot's position moves to the movement point corresponding to the revised position of the search point, and the sensor detects the work position.

[0011] A first teaching point generating method of the present disclosure generates teaching points for a robot device including a robot and a work tool. The teaching point generating method includes a search point calculating step of calculating the position of a search point for determining a next teaching point along a work line based on at least one teaching point, and a driving step of driving the robot so that the position of the robot moves to a movement point corresponding to the search point. After the position of the robot moves to the movement point, the teaching point generating method includes: Supported by a robotThe method includes a position detection step of detecting, by a sensor, a work position on a work line where the robot device performs work on a workpiece. The teaching point generating method includes a teaching point setting step of setting the position of the teaching point based on the work position detected by the sensor. The positions of a plurality of teaching points along the work line are set by repeating a setting step including a search point calculation step, a driving step, a position detection step, and a teaching point setting step. If the work position cannot be detected by the sensor after the position of the robot has moved to a movement point corresponding to the search point, a step of driving the robot to rotate the sensor around a predetermined rotation axis and a step of detecting the work position at the position after the sensor has rotated are performed. A second teaching point generating method of the present disclosure generates teaching points for a robot device including a robot and a work tool. The teaching point generating method includes a search point calculating step of calculating the position of a search point for determining a next teaching point along a work line based on at least one teaching point, and a driving step of driving the robot so that the position of the robot moves to a movement point corresponding to the search point. After the position of the robot moves to the movement point, the teaching point generating method includes: Supported by a robot The method includes a position detection step of detecting a work position on a work line where the robot device performs work on a workpiece by a sensor. The teaching point generation method includes a teaching point setting step of setting the position of the teaching point based on the work position detected by the sensor. The positions of a plurality of teaching points along the work line are set by repeating a setting step including a search point calculation step, a driving step, a position detection step, and a teaching point setting step. When the work position cannot be detected by the sensor after the position of the robot has moved to a movement point corresponding to the search point, the method includes a step of calculating the position of a corrected search point by making the distance from the teaching point to the search point shorter than the distance from the current teaching point to the search point, a step of driving the robot so that the position of the robot moves to a movement point corresponding to the corrected position of the search point, and a step of calculating the work position by the sensor. of A step of detecting is carried out. A first robot control device of the present disclosure includes: A teaching point is generated for a robotic device including a robot and a work tool. The robot control device includes: At least one processor Equipped At least one processor The method includes a search point calculation step of calculating a position of a search point for determining a next teaching point along a work line based on at least one teaching point, and a driving step of driving the robot so that the position of the robot moves to a moving point corresponding to the search point. After the position of the robot moves to the moving point, the at least one processor executes a position detection step of detecting a work position on the work line where the robot device performs work on a workpiece using a sensor supported by the robot, and a teaching point setting step of setting the position of the teaching point based on the work position detected by the sensor. The at least one processor sets the positions of the multiple teaching points along the work line by repeating a setting step including the search point calculation step, the driving step, the position detection step, and the teaching point setting step. When the sensor cannot detect the work position after the position of the robot moves to the moving point corresponding to the search point, the at least one processor executes a step of driving the robot so as to rotate the sensor around a predetermined rotation axis, and a step of detecting the work position at a position after the sensor has rotated. A second robot control device of the present disclosure includes: A teaching point is generated for a robotic device including a robot and a work tool. The robot control device includes:At least one processor Equipped At least one processor The method includes a search point calculation step of calculating a position of a search point for determining a next teaching point along a work line based on at least one teaching point, and a driving step of driving the robot so that the position of the robot moves to a moving point corresponding to the search point. After the position of the robot moves to the moving point, the at least one processor executes a position detection step of detecting a work position on the work line where the robot device performs work on a workpiece using a sensor supported by the robot, and a teaching point setting step of setting the position of the teaching point based on the work position detected by the sensor. The at least one processor sets the positions of the multiple teaching points along the work line by repeating a setting step including the search point calculation step, the driving step, the position detection step, and the teaching point setting step. When the sensor cannot detect the work position after the position of the robot moves to the moving point corresponding to the search point, the at least one processor executes a step of calculating a corrected position of the search point by making the distance from the teaching point to the search point shorter than the distance from the current teaching point to the search point. At least one processor executes a step of driving the robot so that the position of the robot moves to a movement point corresponding to the position of the corrected search point, and a step of detecting the work position with a sensor. Effect of the Invention

[0012] According to an aspect of the present disclosure, a teaching point generating device that automatically sets the position of a teaching point , a robot control device, And a teaching point generating method can be provided. [Brief description of the drawings]

[0013] [Figure 1] 1 is a schematic diagram of a robot device according to an embodiment. [Diagram 2] FIG. 1 is a block diagram of a robot device according to an embodiment. [Diagram 3] 1 is a perspective view of a workpiece and a welding torch when a robot device according to an embodiment is performing welding. FIG. [Figure 4] FIG. 2 is an enlarged perspective view of a welding torch and a laser sensor according to an embodiment. [Diagram 5] FIG. 2 is a perspective view of a workpiece and a welding torch when a start teaching point for starting welding is set. [Figure 6] FIG. 13 is a perspective view of the workpiece and the welding torch when the welding torch is retracted from the start teaching point. [Figure 7] 1 is a perspective view of a workpiece and a welding torch when the welding torch is moved to a position corresponding to a search point. FIG. [Figure 8] 11A and 11B are diagrams illustrating control for setting the positions of a search point and a next teaching point based on two teaching points. [Figure 9] 13 is another diagram illustrating the control for setting the positions of the search point and the next teaching point based on two teaching points. FIG. [Figure 10] 11A and 11B are diagrams illustrating teaching points generated by setting control in the embodiment. [Figure 11] 1 is a perspective view of a workpiece and a welding torch when the welding torch has advanced to a position corresponding to an end teaching point. FIG. [Figure 12]FIG. 11 is a diagram illustrating a first step of control when a work position where welding is to be performed cannot be detected by a laser sensor. [Figure 13] 11 is a diagram illustrating a second step of control when the laser sensor cannot detect a work position where welding is to be performed. FIG. [Figure 14] FIG. 1 is a diagram of a welding path when welding along a weld line including straight and curved lines. [Figure 15] FIG. 2 is a perspective view of a workpiece and a welding torch when regeneration control is being performed in an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] A teaching point generating device and a teaching point generating method according to an embodiment will be described with reference to Fig. 1 to Fig. 15. In the present embodiment, a robot device that fixes a plurality of workpieces by arc welding will be described as an example.

[0015] Fig. 1 is a schematic diagram of a robot device in this embodiment. Fig. 2 is a block diagram of the robot device in this embodiment. With reference to Figs. 1 and 2, a robot device 8 includes a welding torch 2 as a work tool, and a robot 1 that moves the welding torch 2. Robot 1 in this embodiment is an articulated robot including a plurality of joints.

[0016] The robot 1 includes a base 14 and a swivel base 13 supported by the base 14. The base 14 is fixed to an installation surface. The swivel base 13 rotates relative to the base 14. The robot 1 includes an upper arm 11 and a lower arm 12. The lower arm 12 is supported by the swivel base 13 via a joint. The upper arm 11 is supported by the lower arm 12 via a joint. The robot 1 includes a wrist 15 connected to an end of the upper arm 11. The wrist 15 is supported by the upper arm 11 via a joint. The welding torch 2 is fixed to a flange 16 of the wrist 15. The work tool is not limited to a welding torch, and any device can be used depending on the work performed by the robot device.

[0017] The robot 1 of this embodiment has six drive shafts. The robot 1 includes a robot drive device that drives the components of the robot 1, such as the upper arm 11. The robot drive device of this embodiment includes a plurality of robot drive motors 22 for driving the upper arm 11, the lower arm 12, the swivel base 13, and the wrist 15. The position and posture of the robot 1 change as the orientation of the components of the robot 1 changes at the joints.

[0018] The control device 10 of the robot device 8 includes a robot control device 4 that controls the robot 1. The robot control device 4 includes an arithmetic processing device (computer) having a CPU (Central Processing Unit) as a processor. The arithmetic processing device has a RAM (Random Access Memory), a ROM (Read Only Memory), etc., connected to the CPU via a bus.

[0019] Robot device 8 includes a wire supplying device 18 for supplying wire 19 to welding torch 2. Wire supplying device 18 supplies wire 19, which is consumed as welding is performed, to welding torch 2. Wire supplying device 18 in this embodiment is fixed to robot 1.

[0020] The control device 10 of the robot device 8 includes a welding control device 5 that controls the welding torch 2 and the wire supply device 18. The welding control device 5 includes an arithmetic processing device having a CPU as a processor and a RAM etc. connected to the CPU via a bus. The welding control device 5 also includes an electric circuit that supplies electricity to the welding torch 2 and the wire supply device 18. The welding control device 5 is formed so as to be able to communicate with the robot control device 4. The welding control device 5 supplies electricity to the welding torch 2 and supplies wire 19 in accordance with the operation of the robot 1. The welding control device 5 of this embodiment is controlled by the robot control device 4.

[0021] The robot control device 4 includes a teaching operation panel 3 serving as an operation panel for the worker to manually operate the robot device 8. The teaching operation panel 3 includes an input section 3a for inputting information relating to the robot 1 and the welding torch 2. The input section 3a is composed of components such as a keyboard and a dial. The teaching operation panel 3 includes a display section 3b for displaying information relating to the control of the robot device 8. The display section 3b is composed of a display panel such as a liquid crystal display panel. The display section 3b may include a touch panel type display panel. In this case, the display section 3b has the function of the input section 3a.

[0022] Robot control device 4 drives the robot and the work tool in accordance with operation program 40. Operation program 40 in this embodiment includes an operation program 41 for causing robot device 8 to perform a predetermined operation such as welding. The position and posture of robot 1 are changed based on teaching points defined in operation program 41. Welding control device 5 supplies current to welding torch 2 and controls wire feeder 18 based on operation program 41.

[0023] The robot control device 4 includes a storage unit 42 that stores information related to the control of the robot 1 and the welding torch 2. The storage unit 42 can be configured with a non-transitory storage medium capable of storing information, such as a volatile memory, a non-volatile memory, or a hard disk. An operation program 40 including a task program 41 and a teaching point generating program 47 is stored in the storage unit 42.

[0024] In the work program 41, teaching points for driving the robot device 8 are defined. The robot control device 4 includes a motion control unit 43 that sends out motion commands for the robot 1 and the welding torch 2. The motion control unit 43 corresponds to a processor that drives in accordance with the work program 41. The processor functions as the motion control unit 43 by reading the work program 41 and implementing the control defined in the work program 41. Alternatively, the processor functions as the motion control unit 43 by driving the robot 1 based on a command from the processing unit 51 or a command from the playback control unit 60.

[0025] The operation control unit 43 sends an operation command for driving the robot 1 to the robot driving unit 45. The robot driving unit 45 includes an electric circuit for driving the robot driving motor 22. The robot driving unit 45 supplies electricity to the robot driving motor 22 based on the operation command. The operation control unit 43 also controls the operation of the welding torch 2. The operation control unit 43 sends an operation command for driving the welding torch 2 and the wire supply device 18 to the welding control device 5 based on the work program 41. The welding control device 5 supplies electricity to the welding torch 2 and the wire supply device 18 based on the operation command.

[0026] The robot 1 includes a state detector for detecting the position and posture of the robot 1. The state detector in this embodiment includes a position detector 23 attached to the robot drive motor 22. The orientation of the members of the robot 1 in each drive shaft can be obtained from the output of the position detector 23. For example, the position detector 23 detects the rotation angle when the robot drive motor 22 is driven. In this embodiment, the position and posture of the robot 1 are detected based on the outputs of the multiple position detectors 23.

[0027] A world coordinate system 71 is set in the robot device 8 of this embodiment. In the example shown in FIG. 1, the origin of the world coordinate system 71 is located on the base unit 14 of the robot 1. The world coordinate system 71 is also referred to as the reference coordinate system of the robot device 8. The world coordinate system 71 is a coordinate system in which the position of the origin is fixed and the orientation of the coordinate axes is fixed. Even if the position and posture of the robot 1 change, the position and orientation of the world coordinate system 71 do not change. The world coordinate system 71 has, as its coordinate axes, an X-axis, a Y-axis, and a Z-axis that are orthogonal to each other. In addition, the W-axis is set as the coordinate axis around the X-axis. The P-axis is set as the coordinate axis around the Y-axis. The R-axis is set as the coordinate axis around the Z-axis.

[0028] In this embodiment, a tool coordinate system is set with an origin set at an arbitrary position of the work tool. The origin of the tool coordinate system 72 in this embodiment is set at the tool tip point. The tool coordinate system 72 has an X-axis, a Y-axis, and a Z-axis that are mutually orthogonal as coordinate axes. The tool coordinate system 72 has a W-axis around the X-axis, a P-axis around the Y-axis, and an R-axis around the Z-axis. In the example shown in FIG. 1, the tool coordinate system 72 has an origin set at the tip point of the wire 19. The tool coordinate system 72 is also set so that the extension direction of the Z-axis is parallel to the extension direction of the wire 19 protruding from the tip of the welding torch 2.

[0029] When the position and posture of the robot 1 change, the position and orientation of the origin of the tool coordinate system 72 change. For example, the position of the robot 1 corresponds to the position of the tool tip point (the position of the origin of the tool coordinate system 72). Moreover, the posture of the robot 1 corresponds to the orientation of the tool coordinate system 72 with respect to the world coordinate system 71.

[0030] The robot device 8 includes a teaching point generating device that generates teaching points for the robot device 8 including the robot 1 and the welding torch 2. In this embodiment, the robot control device 4 functions as the teaching point generating device. The robot control device 4 includes a laser sensor 27 as a sensor for detecting a work position on a work line of a workpiece on which the robot device 8 performs work. In this embodiment, a welding position as a work position on the welding line of the workpieces 81, 82 is detected based on the output of the laser sensor 27. In addition, a teaching point generating program 47 that drives the robot device 8 to generate teaching points is generated in advance.

[0031] The sensor for detecting the work position where the robot device 8 performs work is not limited to a laser sensor, and any sensor capable of detecting the work position can be used. For example, a three-dimensional sensor can be used as the sensor. As the three-dimensional sensor, a TOF (Time of Flight) camera that captures distance images using a time-of-flight method or a stereo camera that detects a three-dimensional position based on the parallax of images captured by two two-dimensional cameras can be used.

[0032] The robot control device 4 includes a processing unit 51 that processes the output of the laser sensor 27 to generate a teaching point. The processing unit 51 includes a work position detection unit 52 that detects a work position where the welding torch 2 performs work based on the output of the laser sensor 27. The processing unit 51 includes a search point calculation unit 53 that calculates the position of a search point for determining a next teaching point along a work line based on at least one teaching point. The processing unit 51 includes a command unit 54 that drives the robot 1 so that the position of the robot 1 moves to a movement point corresponding to the search point. The processing unit 51 also includes a teaching point setting unit 55 that sets the position of the teaching point based on the work position detected by the laser sensor 27 after the position of the robot 1 moves to the movement point. The setting of the teaching point in this embodiment includes setting the position of the teaching point and setting the attitude of the robot at the teaching point.

[0033] Each unit of the processing unit 51, the work position detection unit 52, the search point calculation unit 53, the command unit 54, and the teaching point setting unit 55 corresponds to a processor that operates according to the teaching point generation program 47. The processor reads the teaching point generation program 47 and performs the control defined in the teaching point generation program 47, thereby functioning as each unit.

[0034] Fig. 3 shows an enlarged perspective view of a workpiece and a welding torch when welding is being performed by the robot device in this embodiment. With reference to Figs. 1 and 3, in this embodiment, a workpiece 81 is placed on the upper surface of a stand 89. A workpiece 82 is placed on the upper surface of the workpiece 81. In this embodiment, the workpieces 81 and 82 are plate-shaped members. In this embodiment, the surfaces of the workpieces 81 and 82 are each flat. The workpieces 81 and 82 are fixed to the stand 89 by a jig (not shown).

[0035] Robot device 8 welds the portion where the top surface of workpiece 81 and the end surface of workpiece 82 come into contact. The boundary between the top surface of workpiece 81 and the end surface of workpiece 82 becomes a weld line WL1 as a work line along which work should be performed. Robot control device 4 changes the position and posture of robot 1 so that the tool tip point of welding torch 2 moves along weld line WL1, as shown by arrow 91. A bead 80 is formed in the welded portion. The teaching point generating device of this embodiment generates teaching points for robot device 8 that performs such work.

[0036] FIG. 4 shows an enlarged perspective view of the welding torch and the laser sensor in this embodiment. The laser sensor 27 in this embodiment is supported by the robot 1. The laser sensor 27 is fixed to the welding torch 2 via a support member 27a. The laser sensor 27 in this embodiment emits laser light in an irradiation range 30 with a predetermined emission angle. The irradiation range 30 is planar. In particular, the irradiation range 30 in this embodiment is fan-shaped. FIG. 4 shows a state in which the planar surface of the workpiece is irradiated with laser light. An irradiation line 32 along which the laser light is irradiated is defined on the surface of the workpiece in correspondence with the irradiation range 30. In this embodiment, a line passing through a predetermined point on the laser sensor 27 and the midpoint of the width W of the irradiation line 32 is referred to as a center line 31 of the irradiation range 30.

[0037] As the laser sensor 27, any sensor having a mechanism for emitting laser light in a sector-shaped irradiation range 30 can be used. For example, a sensor in which the laser light is deflected and scanned can be used. The sensor in which the laser light is deflected and scanned includes a swing mirror that changes the emission direction of the laser light. The swing mirror swings, so that the laser light is emitted within a range of a predetermined emission angle. In addition, this laser sensor includes a light receiving element that receives the laser light reflected on the surface of the workpiece. Based on the direction of the laser light emitted by the swing mirror and the position of the laser light on the light receiving element, the position where the laser light is reflected on the workpiece can be detected. In particular, the position along the width direction of the irradiation range and the distance from the laser sensor to the surface of the workpiece can be detected. The position where the laser light is reflected can be calculated in the coordinate system of the sensor set for the laser sensor.

[0038] The position where the laser light is reflected on the surface of the workpiece can be calculated by the coordinate system of the sensor. Then, a line connecting the multiple positions detected by scanning the laser light can be generated. A welding position on the welding line can be detected based on the line connecting the multiple positions. For example, a point where the line connecting the multiple positions bends can be set as a welding position where welding should be performed. Also, based on the position and posture of the robot 1, the welding position expressed in the coordinate system of the sensor can be converted to a welding position expressed in the world coordinate system 71.

[0039] FIG. 5 shows a perspective view of the workpiece and the welding torch when the robot is positioned at the start teaching point where welding starts. First, the worker sets the start teaching point TPS, which is a teaching point indicating the start of welding. The worker can set the start teaching point TPS by manually driving the robot 1. The worker operates the input unit 3a of the teaching operation panel 3 to change the position and posture of the robot 1. Then, the worker adjusts the position of the robot 1 so that the tip of the wire 19 (tool tip point) is placed at the start point of welding. In addition, the worker adjusts the posture of the robot 1 so that the welding torch 2 has the desired target angle and forward angle. In this embodiment, the forward angle is taken as an example for explanation, but the backward angle may also be used.

[0040] At this time, it is preferable for the worker to adjust the rotational position of the flange 16 of the wrist 15 so that the laser sensor 27 is disposed in the direction in which the weld line WL1 extends. In particular, it is preferable to dispose the laser sensor 27 so that the weld line WL1 to be welded is within the irradiation range 30 of the laser light.

[0041] In this manner, in this embodiment, the start teaching point is set in advance. The start teaching point can be set by any method. For example, the operator may set the start teaching point TPS by inputting coordinate values ​​of a predetermined coordinate system from the input unit 3a of the teaching pendant 3. Next, the operator operates the input unit 3a of the teaching pendant 3, and the robot control device 4 starts control for automatically generating a teaching point.

[0042] FIG. 6 shows a perspective view when the welding torch is retracted in a predetermined direction from the start teaching point. With reference to FIGS. 1, 2 and 6, the command unit 54 of the processing unit 51 executes control to retract the welding torch 2 from the workpieces 81, 82 in a predetermined direction and at a predetermined distance from the start teaching point TPS. In this example, the command unit 54 changes the position of the robot 1 so as to move the welding torch 2 in the direction of the Z axis of the tool coordinate system 72. The position of the robot 1 moves from the start teaching point TPS to the movement point MPS. As shown by the arrow 93, the tip point of the wire 19 moves in a direction away from the start teaching point TPS. The direction in which the welding torch 2 is retracted is not limited to the direction of the Z axis of the tool coordinate system 72, and any direction away from the workpieces 81, 82 can be adopted. At this time, it is preferable to move the welding torch 2 in a direction and at a distance that allows the laser sensor 27 to capture an image of the welding line WL1.

[0043] Robot control device 4 performs setting control to set the position of the teaching point while moving welding torch 2 along weld line WL1. In this embodiment, the setting of the position of the teaching point is repeated while maintaining a state in which welding torch 2 is retracted from workpieces 81, 82. That is, with the tool tip point separated from weld line WL1, the position of the teaching point is set while moving welding torch 2 in a direction along weld line WL1.

[0044] In this embodiment, during the period in which the setting control for setting the position of the teaching point is performed, the robot 1 is set to a predetermined posture. For example, the worker can input the posture of the robot 1 for performing the setting control in advance to the robot control device 4. Alternatively, the posture of the robot 1 when the worker sets the start teaching point TPS may be maintained.

[0045] First, the teaching point setting unit 55 sets the position of the teaching point TP1 based on the position of the start teaching point TPS. A welding line WL1 as a work line is arranged inside the irradiation range 30 of the laser light of the laser sensor 27. The irradiation range 30 intersects with the direction in which the welding line WL1 extends. The work position detection unit 52 detects the position of the welding line WL1, that is, the welding position where welding should be performed, based on the output of the laser sensor 27. The teaching point setting unit 55 in this embodiment sets this welding position to the position of the teaching point TP1.

[0046] Fig. 7 shows a perspective view of a welding torch and a workpiece for explaining the control for setting the position of the next teaching point. Fig. 8 shows a diagram for explaining the control for setting the position of the next teaching point. With reference to Figs. 7 and 8, processing unit 51 generates the next teaching point TP2 along the welding line WL1 based on teaching points TPS and TP1 that have already been set.

[0047] The search point calculation unit 53 performs a search point calculation process of calculating the position of a search point for determining a next teaching point along the weld line WL1 based on at least one teaching point. The search point calculation unit 53 calculates a straight line extending from the start teaching point TPS to the teaching point TP1, as shown by an arrow 94. The search point calculation unit 53 sets a search point SP2 on an extension of the straight line of the arrow 94, as shown by an arrow 95. The distance from the reference teaching point to the search point can be determined in advance. In this example, the straight line distance from the teaching point TPS to the search point SP2 can be determined in advance.

[0048] Next, the command unit 54 executes a drive step of driving the robot 1 so that the position of the robot 1 moves to a movement point MP2 corresponding to the search point SP2. The command unit 54 calculates the position of the movement point MP2, which is the position of the robot 1 corresponding to the search point SP2. The command unit 54 calculates the position of the movement point MP2 obtained by moving the position of the robot 1 from the movement point MPS in the same direction and distance as the direction and distance from the teaching point TP1 toward the search point SP2 (the direction and distance indicated by the arrow 95). The command unit 54 drives the robot 1 so that the robot 1 is located at the position of the calculated movement point MP2. The command unit 54 moves the welding torch 2 as indicated by the arrow 96.

[0049] Next, the work position detection unit 52 performs a position detection process of detecting the work position on the weld line WL1 by the laser sensor 27. After the position of the robot 1 moves to the movement point MP2 corresponding to the search point SP2, the work position detection unit 52 detects the welding position where welding is performed on the workpieces 81, 82 based on the output of the laser sensor 27.

[0050] Next, the teaching point setting unit 55 performs a teaching point setting process in which the teaching point is set based on the welding position detected by the laser sensor 27. The teaching point setting unit 55 of this embodiment acquires the welding position from the work position detection unit 52, and sets this welding position to the position of the teaching point TP2. In the example shown in Fig. 7 and Fig. 8, the teaching point TP2 is slightly shifted from the search point SP2.

[0051] In this embodiment, the control including the calculation of the positions of the search points by the search point calculation unit 53, the driving of the robot 1 by the command unit 54, and the setting of the positions of the taught points by the taught point setting unit 55 is referred to as setting control. The robot control device 4 generates multiple taught points along the weld line WL1 by repeating the setting control. The robot control device 4 also sets the positions of the multiple taught points. In other words, the robot control device 4 sets the positions of the multiple taught points along the weld line WL1 by repeating a setting process including a search point calculation process, a driving process, a position detection process, and a taught point setting process.

[0052] Fig. 9 is a diagram for explaining the control for setting the position of the next teaching point. With reference to Fig. 7 and Fig. 9, the processing unit 51 repeats the same setting control as the setting control for setting the position of the teaching point TP2. The processing unit 51 of this embodiment sets the teaching point TP3 based on the teaching points TP1 and TP2 set in the nearest control.

[0053] The search point calculation unit 53 calculates a straight line from the teaching point TP1 to the teaching point TP2, as shown by an arrow 96. The search point calculation unit 53 sets a search point SP3 on an extension of the straight line shown by the arrow 96, as shown by an arrow 97. A predetermined distance can be adopted as the distance from the teaching point TP2 to the search point SP3. For example, the distance from the teaching point TP2 to the search point SP3 can be set to be the same as the distance from the teaching point TPS to the search point SP2. The search point calculation unit 53 calculates the position of the search point SP3 for determining the next teaching point TP3 based on the position of the teaching point TP2 set in the previous setting control and the position of the teaching point TP1 set before the teaching point TP2 set in the previous setting control.

[0054] The command unit 54 calculates the position of the movement point corresponding to the search point SP3. The command unit 54 calculates the direction and distance from the search point SP2 to the search point SP3. The command unit 54 calculates the position of the movement point corresponding to the search point SP3 based on the direction and distance from the search point SP2 to the search point SP3 and the position of the movement point MP2. The command unit 54 moves the position of the robot 1 to the movement point corresponding to the search point SP3. Here, the command unit 54 changes the position of the robot 1 so that the center line 31 of the irradiation range 30 passes through the search point SP3. In this embodiment, the extension direction of the irradiation line 32 at this time is parallel to the irradiation line 32 when the workpieces 81, 82 are irradiated with the laser light at the movement point MP2.

[0055] After moving the robot 1 to a movement point corresponding to the search point SP3, the work position detection unit 52 detects the welding position based on the output of the laser sensor 27. Then, the teaching point setting unit 55 sets the teaching point TP3 based on the welding position detected by the work position detection unit 52.

[0056] Fig. 10 shows a welding path generated by repeating the setting control. The path passing through teaching points TPS, TP1, TP2, and TP3 becomes a welding path WP1 as a work path. In this way, the teaching point generating device of this embodiment can generate teaching points and set their positions by repeating the setting control. Also, in the teaching point generating method of this embodiment, the setting process is repeated to generate teaching points and set their positions.

[0057] The teaching point setting unit 55 can calculate a working path based on the positions of the teaching points. The teaching point setting unit 55 can set the posture of the robot 1 at each teaching point based on the working path. For example, the teaching point setting unit 55 can set the posture of the robot 1 based on the generated working path so that the posture of the welding torch becomes a predetermined forward angle or backward angle and a predetermined target angle. The teaching point setting unit 55 can calculate the posture of the robot 1 for each teaching point.

[0058] In the teaching point generating device and teaching point generating method of the present embodiment, teaching points can be generated without generating a reference robot path in advance. Furthermore, since teaching points can be generated automatically, even workers with low skills can easily generate teaching points. Furthermore, workers can generate teaching points in a short time. Furthermore, since a sensor detects a welding position on a weld line, teaching points can be set at accurate positions.

[0059] In this embodiment, the search point calculation unit 53 calculates the position of the search point for determining the next teaching point based on the position of the teaching point set in the previous setting control and the position of the teaching point set before the teaching point set in the previous setting control. This control makes it possible to set a search point in the vicinity of the next teaching point using the teaching point already set. In particular, the search point calculation unit 53 of this embodiment calculates the position of the search point based on the position of the teaching point set in the previous setting control and the position of the teaching point set in the setting control two times before. That is, the search point calculation unit 53 calculates the position of the search point based on the positions of two consecutive teaching points. The control of calculating the position of the search point based on the positions of two consecutive teaching points can reduce the amount of calculation to calculate the search point.

[0060] The search point calculation unit 53 may calculate the position of a search point corresponding to the next teaching point based on the positions of three or more teaching points. For example, the search point calculation unit may calculate a straight line by the least squares method based on the positions of three or more teaching points, and set a search point on this straight line. In the above embodiment, the search point is set on the extension of the straight line connecting the multiple teaching points, but this is not limited to this embodiment. For example, the search point calculation unit may set a search point on the extension of a curve such as a circular arc that passes through the multiple teaching points.

[0061] In this embodiment, the setting control is performed while maintaining the welding torch 2 in a state of being retracted from the workpieces 81 and 82. By performing this control, it is possible to prevent the welding torch 2 from colliding with the workpieces 81 and 82 or with fixed members or the like arranged around the workpieces 81 and 82. For example, when the workpiece is curved, the welding torch may collide with the workpiece when the welding torch moves in a straight line to the movement point corresponding to the search point. By setting the position of the teaching point with the welding torch separated from the workpiece, it is possible to prevent the welding torch from colliding with other objects. Note that the setting control may be performed without retracting the welding torch from the workpiece. In other words, the position of the teaching point may be set while maintaining the state in which the tool tip point is arranged in the vicinity of the weld line.

[0062] The sensor in this embodiment is a laser sensor 27 that emits laser light in a planar irradiation range 30 with a predetermined emission angle. By adopting this configuration, the position of the welding torch 2 can be controlled using the width direction of the irradiation range 30 of the laser light and the center line 31 of the irradiation range 30.

[0063] FIG. 11 shows a perspective view of the workpiece and the welding torch when the welding position detected by the laser sensor reaches the end point of welding by repeating the setting control. In the example shown in FIG. 11, a start teaching point TPS, teaching points TP1 to TP4, and an end teaching point TPE are shown. The condition for ending the setting control can be determined in advance. For example, the range of the position of the search point at which the setting control ends can be determined in advance. When the search point calculated by the search point calculation unit 53 reaches within a predetermined position range, the teaching point detected corresponding to the search point can be set as the end teaching point TPE, which is the teaching point at which the work ends.

[0064] Alternatively, the range of the position of the end teaching point can be determined in advance. If the newly generated teaching point is within the range of the position of the end teaching point, the teaching point can be set as the end teaching point TPE, and the setting control can be terminated.

[0065] Alternatively, the setting control may be terminated if, after the position of the robot has moved to a movement point corresponding to the search point, the work position detection unit 52 cannot detect the welding position based on the output of the laser sensor 27. In this case, the teaching point setting unit 55 can set the last teaching point set among the teaching points that have already been set as the end teaching point TPE.

[0066] Alternatively, when the laser beam reaches the vicinity of the welding end point, the operator may end the setting control by operating the teaching operation panel 3. Then, the operator may operate the teaching operation panel 3 to move the welding torch 2 and set the end teaching point TPE.

[0067] FIG. 12 is a diagram for explaining control when the welding position cannot be detected by the laser sensor. In the example shown in FIG. 12, a teaching point is generated along the welding line WL4. The welding line WL4 has a curved portion with a small radius of curvature. In this example, a search point SP2 is calculated based on the start teaching point TPS and the teaching point TP1. Furthermore, the position of the robot 1 is moved to a moving point corresponding to the search point SP2, and the position of the teaching point TP2 is set.

[0068] Next, the search point calculation unit 53 calculates the position of the search point SP3 based on the positions of the teaching points TP1 and TP2. The command unit 54 calculates the position of the movement point corresponding to the search point SP3. The command unit 54 changes the position of the robot 1 so that the center line 31 of the irradiation range 30 of the laser light passes through the search point SP3. However, the irradiation line 32 of the laser light is away from the welding line WL4. For this reason, the work position detection unit 52 cannot detect the welding position based on the output of the laser sensor 27. In this way, there are cases where the welding position cannot be detected based on the output of the laser sensor 27 after the position of the robot 1 moves to the movement point.

[0069] In this case, command unit 54 can drive robot 1 to rotate laser sensor 27 around a predetermined rotation axis 101. With reference to Figs. 4 and 12, in this example, the drive axis of flange 16 of robot 1 is set to rotation axis 101. Command unit 54 performs control to rotate welding torch 2 around rotation axis 101, as shown by arrow 92. The rotation of welding torch 2 rotates laser sensor 27.

[0070] The angle by which the laser sensor 27 is rotated can be determined in advance. For example, the command unit 54 can rotate the laser sensor 27 within a range of a predetermined angle with respect to the direction from the teaching point TP2 toward the search point SP3, as indicated by the arrow 97. The command unit 54 can stop the rotation of the laser sensor 27 at each predetermined angle. Then, the work position detection unit 52 detects the work position at the position after the rotation.

[0071] Fig. 13 shows the state when the laser sensor is rotated. With reference to Fig. 12 and Fig. 13, by rotating the laser sensor 27 around the rotation axis 101, the welding line WL4 passes within the range of the irradiation line 32. The work position detection unit 52 can detect the welding position based on the output of the laser sensor 27.

[0072] In this way, when the work position cannot be detected from the output of the laser sensor 27, it is possible to perform a periphery search control for detecting the welding position by rotating the laser sensor 27. The teaching point setting unit 55 sets the welding position detected by the periphery search control to the position of the teaching point TP3. By performing this control, when the welding line WL4 is in the vicinity of the irradiation range 30 of the laser sensor 27, the welding position can be detected.

[0073] In this embodiment, the drive shaft of the flange 16 is used as the rotation axis for rotating the laser sensor 27, but this is not limited to the embodiment. The laser sensor can rotate around any rotation axis. For example, the Z axis of the tool coordinate system 72 can be used as the rotation axis. Also, any axis passing through the tool tip point can be used as the rotation axis. Furthermore, a rotation axis set at a position away from the welding torch may be used. With reference to FIG. 6, this periphery search control may be performed when the next teaching point TP1 cannot be detected from the output of the laser sensor 27 at the position where the welding torch 2 is retracted from the start teaching point TPS to the moving point MPS.

[0074] 12, if the welding position cannot be detected by laser sensor 27 after robot 1 has moved to a movement point corresponding to the search point, search point calculation unit 53 can implement control to shorten the distance from teaching point TP2 to search point SP3, as indicated by arrow 97. That is, control can be implemented to shorten the movement distance of welding torch 2 when moving from the movement point corresponding to search point SP2 to the movement point corresponding to search point SP3.

[0075] The search point calculation unit 53 sets the distance from the teaching point TP2 to the search point to be shorter than the distance from the current teaching point TP2 to the search point SP3. That is, the movement distance indicated by the arrow 97 is shortened to calculate the position of the corrected search point. The method of setting the distance from the teaching point TP2 to the corrected search point can be determined in advance. Then, the command unit 54 drives the robot 1 to the movement point corresponding to the corrected search point. After this, the work position detection unit 52 detects the welding position based on the output of the laser sensor 27.

[0076] In this way, when the work position cannot be detected based on the output of the laser sensor 27, a travel distance change control for shortening the distance from the teaching point to the search point can be performed. By performing this control, the distance from the already generated teaching point to the search point is shortened. Even if the welding line WL4 is bent or curved, the distance from the search point to the welding line can be shortened. As a result, the possibility that the welding position can be detected by the laser sensor 27 is improved. The travel distance change control can be repeatedly performed. For example, when the work position cannot be detected even after performing the travel distance change control to shorten the distance from the teaching point to the search point, the travel distance change control can be further performed.

[0077] The above-mentioned periphery search control and the movement distance change control can be implemented in combination. For example, the processing unit 51 can implement the movement distance change control when the welding position cannot be detected even after implementing the periphery search control. Alternatively, the processing unit 51 can implement the periphery search control when the welding position cannot be detected even after implementing the movement distance change control.

[0078] Fig. 14 is a diagram for explaining control for setting the positions of teaching points for a welding line including a straight welding line and a curved welding line. The welding line WL5 includes a straight portion and a curved portion. In Fig. 14, the irradiation lines 32 of the laser light at the respective teaching points TP1 to TP6 are shown on the welding line WL5. As described above, when the welding line is curved, there are cases where the welding position on the welding line cannot be detected after the position of the robot 1 moves to the search point.

[0079] Therefore, when the weld line WL5 along the path from the teaching point to the search point is linear, the search point calculation unit 53 can set the distance from the teaching point to the search point to a first distance. In each section IL1, the weld line WL5 extends linearly, so the distance from the teaching point to the search point is set to the first distance. On the other hand, when the weld line WL5 along the path from the teaching point to the search point is curved, the search point calculation unit 53 can set the distance from the teaching point to the search point to a second distance smaller than the first distance. In each section IL2, the weld line WL5 extends curved, so the distance from the teaching point to the search point is set to the second distance. The interval between the teaching points in the section IL2 is narrower than the interval between the teaching points in the section IL1.

[0080] The section in which the search point is detected at the first distance and the section in which the search point is detected at the second distance can be determined in advance. For example, for the position of the search point, the range of the section IL1 in which the search point is detected at the first distance and the range of the section IL2 in which the search point is detected at the second distance can be determined in advance.

[0081] Alternatively, the operator can change the distance from the teaching point to the search point by operating the teaching operation panel 3. The input section 3a of the teaching operation panel 3 in this embodiment is formed so that the distance from the teaching point to the search point can be adjusted. For example, a distance change button for changing the distance is disposed on the input section 3a. When the distance change button is not pressed, the search point calculation section 53 can set the distance from the teaching point to the search point to a first distance. Also, when the distance change button is pressed, the search point calculation section 53 can set the distance from the teaching point to the search point to a second distance.

[0082] The worker checks the position of the welding torch 2 while the welding torch 2 is moving and the position of the teaching point is being set. The worker can change the distance from the teaching point to the search point by operating the distance change button. The worker can manually adjust the distance from the teaching point to the search point based on the position of the welding torch 2 while the setting control is being performed. Note that three or more sections for changing the travel distance may be set. Also, the travel distance may be changed using three or more types of travel distance.

[0083] Fig. 15 shows a perspective view of a workpiece and a welding torch when the robot device is actually driven based on the teaching points generated by the setting control. With reference to Figs. 2 and 15, the robot control device 4 includes a playback control unit 60 that performs playback control to drive the robot 1 based on the teaching points generated by the setting control. The playback control unit 60 corresponds to a processor that drives according to the teaching point generation program 47. The processor functions as the playback control unit 60 by reading the teaching point generation program 47 and performing control defined in the teaching point generation program 47.

[0084] The playback control unit 60 acquires the positions of the teaching points set by the teaching point setting unit 55. The playback control unit 60 also acquires the posture of the robot 1 at the teaching points set by the teaching point setting unit 55. The posture of the robot 1 when performing playback control may be the posture of the robot 1 when performing setting control. The playback control unit 60 sends a command to the operation control unit 43 to drive the robot 1 so as to move the welding torch 2 without driving the welding control device 5. The worker can check the changes in the position and posture of the robot 1 when actually performing welding.

[0085] The tip point of the wire 19 (tool tip point) moves along the welding line WL1 as indicated by an arrow 99. At this time, the work position detection unit 52 may detect the welding position again based on the output of the laser sensor 27. The teaching point setting unit 55 may correct the positions of the teaching points that have already been generated, based on the welding position detected by the work position detection unit 52.

[0086] In this embodiment, when performing playback control, the playback control unit 60 reduces the moving speed of the welding torch 2 in the vicinity of the end teaching point TPE, which is the end of the work. The playback control unit 60 performs control to reduce the drive speed of the robot 1. The range of positions of the robot 1 where the moving speed of the welding torch 2 is reduced can be determined in advance. Furthermore, the playback control unit 60 may gradually reduce the drive speed of the robot 1 as it approaches the end teaching point TPE.

[0087] The operator stops the playback control by operating the teaching operation panel 3 in the vicinity of the end teaching point TPE. Next, the operator can set the position of the end teaching point TPE by operating the input unit 3a of the teaching operation panel 3 to manually drive the robot 1. That is, the operator can correct the position of the end teaching point TPE. The teaching point setting unit 55 corrects the position of the end teaching point TPE in response to the operator's operation of the input unit 3a. The corrected teaching point can be stored in the memory unit 42.

[0088] For example, when the work position detection unit 52 cannot detect the welding position, the setting control may be terminated. The end teaching point may be set to a position that is different from the desired end teaching point. In this case, the worker can manually correct the end teaching point. Alternatively, since the end teaching point at which welding ends is an important teaching point that greatly affects the quality of the workpiece, the worker can set the position of the end teaching point more accurately.

[0089] The playback control unit 60 of this embodiment executes control to reduce the drive speed of the robot 1 within a predetermined range near the end teaching point. By performing this control, the moving speed of the welding torch 2 is reduced, so that the operator can easily stop the robot 1 at a desired position.

[0090] Incidentally, when actually performing welding work, the robot device 8 places the tip point of the welding torch 2 at a movement point near the start teaching point TPS before starting the actual work, and then controls the welding torch 2 to approach the start teaching point TPS. Such a movement point near the start teaching point TPS is called an approach point. In other words, the robot control device 4 positions the robot 1 at the approach point, and then positions it at the start teaching point TPS.

[0091] With reference to FIG. 6, the teaching point setting unit 55 can set the position and posture of the robot 1 where the welding torch 2 is retracted in a predetermined direction and at a predetermined distance from the start teaching point TPS as the approach point. For example, the teaching point setting unit 55 can set the point where the welding torch 2 is retracted in the direction of the Z axis of the tool coordinate system from the start teaching point TPS as the approach point. With this control, the processing unit 51 can automatically generate a teaching point corresponding to the approach point even if the operator does not teach the approach point. Also, the processing unit 51 can generate the approach point during the period when the control for generating a plurality of teaching points is being performed. The number of teaching points set by the operator can be reduced.

[0092] 15, when the actual welding work is completed, the robot device 8 positions the tip point of the welding torch 2 at a point away from the workpieces 81, 82, and then changes the position and posture of the robot 1 to perform the next work. That is, the robot control device 4 positions the robot 1 at a movement point retreated from the end teaching point TPE, and then changes the position and posture of the robot 1 to perform the next work. This movement point is called an escape point. The teaching point setting unit 55 of this embodiment can automatically set the escape point when the end teaching point TPE is set.

[0093] The teaching point setting unit 55 can set, as the escape point, the position of the robot 1 where the welding torch 2 is retracted from the workpieces 81, 82 in a predetermined direction and at a predetermined distance from the end teaching point TPE, as shown by an arrow 100. For example, the teaching point setting unit 55 can set, as the escape point, a movement point where the welding torch 2 is retracted from the end teaching point TPE in the direction of the Z axis of the tool coordinate system. With this control, the processing unit 51 can automatically generate a teaching point corresponding to the escape point, even if the operator does not teach the escape point. The number of teaching points set by the operator can be reduced.

[0094] In this embodiment, fillet welding is taken as an example to weld a part where two members come into contact and form a corner, but the present invention is not limited to this embodiment. The control of generating the teaching point of this embodiment can also be implemented in butt welding, in which the end faces of two members are welded so that they face each other. In addition, the surface of the workpiece in this embodiment is flat, but the present invention is not limited to this embodiment. The control of this embodiment can also be applied when working on a workpiece that includes a curved surface. For example, when working on a curved surface, the control of this embodiment can be implemented by shortening the distance from the teaching point to the search point.

[0095] Furthermore, in the present embodiment, a robot apparatus that performs arc welding has been described as an example, but the present invention is not limited to this. The control of the present embodiment can be applied to any robot apparatus that performs work along a work line. For example, the control of the present embodiment can be applied to a robot apparatus that performs laser welding or a robot apparatus that includes a work tool that applies adhesive.

[0096] The above-mentioned embodiments can be combined as appropriate. In each of the above-mentioned drawings, the same or equivalent parts are given the same reference numerals. Note that the above-mentioned embodiments are examples and do not limit the invention. In addition, the embodiments include modifications of the embodiments shown in the claims. [Explanation of symbols]

[0097] 1. Robot 2. Welding torch 3 Teaching operation panel 3a Input section 4 Robot control device 8 Robotic Device 10 Control device 27 Laser Sensor 30 Irradiation range 31 Chuo Line 32 Radiation 40 Operation Program 52 Work position detection unit 53 Search point calculation unit 54 Command Department 55 Teaching point setting section 60 Playback control section 81,82 Work 101 Rotation axis TP1~TP6 Teaching points SP1~SP3 Search points MP2 Movement Point WL1,WL4,WL5 welding lines

Claims

1. A teaching point generation device that generates teaching points for a robot device including a robot and a work tool, a sensor supported by the robot for detecting a work position on a work line where the robot device performs a work on a workpiece; a search point calculation unit that calculates a position of a search point for determining a next teaching point along the work line based on at least one teaching point; A command unit that drives the robot so that the position of the robot moves to a movement point corresponding to the search point; a teaching point setting unit that sets a position of a teaching point based on a work position detected by the sensor after the position of the robot has moved to a movement point, a control unit for controlling the robot to move the robot by the command unit and the teaching point setting unit to set the positions of the teaching points along the work line; When the sensor cannot detect a work position after the position of the robot has moved to a movement point, the command unit drives the robot to rotate the sensor around a predetermined rotation axis; A teaching point generating device in which the sensor detects the working position at the position after rotation.

2. A teaching point generation device that generates teaching points for a robot device including a robot and a work tool, a sensor supported by the robot for detecting a work position on a work line where the robot device performs a work on a workpiece; a search point calculation unit that calculates a position of a search point for determining a next teaching point along the work line based on at least one teaching point; A command unit that drives the robot so that the position of the robot moves to a movement point corresponding to the search point; a teaching point setting unit that sets a position of a teaching point based on a work position detected by the sensor after the position of the robot has moved to a movement point, a control unit for controlling the robot to move the robot by the command unit and the teaching point setting unit to set the positions of the teaching points along the work line; when the sensor cannot detect a working position after the position of the robot has moved to the movement point, the search point calculation unit calculates a corrected position of the search point by shortening a distance from a teaching point to the search point to be shorter than a distance from a current teaching point to the search point; the command unit drives the robot so that the position of the robot moves to a movement point corresponding to the position of the corrected search point; The sensor detects a work position. A teaching point generating device.

3. a control panel for manually controlling the operation of the robot device; 3. The teaching point generating device according to claim 1, wherein the operation panel has an input section capable of adjusting a distance from a teaching point to a search point.

4. A teaching point generation device as described in any one of claims 1 to 3, wherein the search point calculation unit sets the distance from the teaching point to the search point to a first distance when a work line along a path from the teaching point to the search point is straight, and sets the distance from the teaching point to the search point to a second distance shorter than the first distance when the work line along the path from the teaching point to the search point is curved.

5. A start teaching point which is a teaching point indicating the start of the work is determined in advance, The command unit executes control to retract the work tool from the workpiece in a predetermined direction and at a predetermined distance from a start teaching point, The teaching point generating device according to claim 1 , wherein the setting control is performed while the work tool is kept retracted from a workpiece.

6. A start teaching point which is a teaching point indicating the start of the work is determined in advance, The teaching point generating device according to any one of claims 1 to 5, wherein the teaching point setting unit performs control to set a position where the work tool is retracted from the workpiece in a predetermined direction and a predetermined distance from a start teaching point as the position of an approach point before starting actual work, and control to set a position where the work tool is retracted from the workpiece in a predetermined direction and a predetermined distance from an end teaching point, which is a teaching point indicating the end of the work, as the position of an escape point after the actual work is completed.

7. an operation panel for manually operating the robot device; a reproduction control unit that performs reproduction control to drive the robot based on the teaching points generated by the setting control, the operation panel has an input unit configured to manually change the position and posture of the robot, the playback control unit, when performing playback control, performs control to reduce a drive speed of the robot so that a movement speed of the work tool decreases within a predetermined range in the vicinity of an end teaching point, which is a teaching point that indicates an end of work, and stops the playback control in response to an operation of the operation panel by a worker; The teaching point generating device according to claim 1 , wherein the teaching point setting unit corrects a position of an end teaching point in response to an operation of an input unit by an operator.

8. A teaching point generation method for generating teaching points for a robot device including a robot and a work tool, comprising: a search point calculation step of calculating a position of a search point for determining a next teaching point along the work line based on at least one teaching point; a driving step of driving the robot so that a position of the robot moves to a movement point corresponding to the search point; a position detection step of detecting, after the position of the robot has been moved to a movement point, a work position on a work line where the robot device performs work on a workpiece by a sensor supported by the robot; a teaching point setting step of setting a teaching point position based on the work position detected by the sensor, By repeating a setting process including a search point calculation process, a drive process, a position detection process, and a teaching point setting process, positions of a plurality of teaching points along the work line are set; A teaching point generating method which, when the sensor cannot detect a working position after the robot's position has moved to a moving point corresponding to a search point, carries out the steps of driving the robot to rotate the sensor around a predetermined rotation axis, and detecting the working position at the position after the sensor has rotated.

9. A teaching point generation method for generating teaching points for a robot device including a robot and a work tool, comprising: a search point calculation step of calculating a position of a search point for determining a next teaching point along the work line based on at least one teaching point; a driving step of driving the robot so that a position of the robot moves to a movement point corresponding to the search point; a position detection step of detecting, after the position of the robot has been moved to a movement point, a work position on a work line where the robot device performs work on a workpiece by a sensor supported by the robot; a teaching point setting step of setting a teaching point position based on the work position detected by the sensor, By repeating a setting process including a search point calculation process, a drive process, a position detection process, and a teaching point setting process, positions of a plurality of teaching points along the work line are set; a step of calculating a corrected position of the search point by shortening a distance from the teaching point to the search point compared to a current distance from the teaching point to the search point when the sensor cannot detect a working position after the position of the robot has moved to a movement point corresponding to the search point; driving the robot so that the position of the robot moves to a movement point corresponding to the position of the corrected search point; detecting a work position by the sensor.

10. A robot control device for generating teaching points for a robot device having a robot and a work tool, comprising: At least one processor; The at least one processor a search point calculation step of calculating a position of a search point for determining a next teaching point along the work line based on at least one teaching point; a driving step of driving the robot so that a position of the robot moves to a movement point corresponding to the search point; a position detection step of detecting, after the position of the robot has been moved to a movement point, a work position on a work line where the robot device performs work on a workpiece by a sensor supported by the robot; a teaching point setting step of setting a teaching point position based on the work position detected by the sensor; By repeating a setting process including a search point calculation process, a drive process, a position detection process, and a teaching point setting process, positions of a plurality of teaching points along the work line are set; A robot control device that executes a process of driving the robot to rotate the sensor around a predetermined rotation axis when the sensor cannot detect a working position after the robot's position has moved to a movement point corresponding to a search point, and a process of detecting the working position at the position after the sensor has rotated.

11. A robot control device for generating teaching points for a robotic device having a robot and a work tool, comprising: At least one processor; The at least one processor a search point calculation step of calculating a position of a search point for determining a next teaching point along the work line based on at least one teaching point; a driving step of driving the robot so that a position of the robot moves to a movement point corresponding to the search point; a position detection step of detecting, after the position of the robot has been moved to a movement point, a work position on a work line where the robot device performs work on a workpiece by a sensor supported by the robot; a teaching point setting step of setting a teaching point position based on the work position detected by the sensor; By repeating a setting process including a search point calculation process, a drive process, a position detection process, and a teaching point setting process, positions of a plurality of teaching points along the work line are set; a step of calculating a corrected position of the search point by shortening a distance from the teaching point to the search point compared to a current distance from the teaching point to the search point when the sensor cannot detect a working position after the position of the robot has moved to a movement point corresponding to the search point; driving the robot so that the position of the robot moves to a movement point corresponding to the position of the corrected search point; and detecting a work position by the sensor.

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