JP3051968B2 - Off-line teaching method of machining robot - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an off-line teaching method for a machining robot capable of teaching a three-dimensional operation of an end effector based on a planar image of a processing object (work).

[0002]

2. Description of the Related Art As a method of teaching a three-dimensional operation of an end effector such as a three-dimensional groove cutting operation in a conventional processing robot, for example, a cutting robot, a teaching playback method using a robot body is used. Display the three-dimensional images of the work and the end effector,
An off-line teaching method for teaching the operation of the end effector while moving it on this image is adopted.

[0003]

In the teaching playback method, it is necessary to stop the operation of the robot during the teaching, so that the operating rate of the robot is reduced. Is difficult to perform. On the other hand, in the offline teaching method using a three-dimensional image,
There is a problem that a great deal of labor is required for teaching.
In the conventional offline teaching method in which a planar image of a workpiece is displayed and teaching is performed on the image, teaching is easy as long as the two-dimensional operation of the end effector is taught, but three-dimensional operation is taught. Is difficult.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and has a process capable of efficiently and accurately teaching a three-dimensional groove cutting operation of an end effector and other three-dimensional operations. An object of the present invention is to provide a method of teaching a robot offline.

[0005]

[0006]

Means for Solving the Problems] claim 1 according to the present invention
The offline teaching method for a machining robot according to (1) is a method for teaching the operation of a machining robot by displaying a planar image of a workpiece on an image display means. A step of collectively registering the movement of the end effector of the machining robot in a three-dimensional space as pattern data in advance, and (b) a planar image of the workpiece input by two-dimensional CAD including a shape to be machined, Displaying on the image display means, (c) specifying the pattern data registered in the step (a), and (d) specifying a reference point of the pattern data on the plane image together with its position. (E) applying the content specified in the pattern data specified in the step (c) to the reference specified in the step (d). In what has been further defined by the position of the one in which and a step of creating teaching data operation on the three-dimensional space including a posture of the end effector.

According to a second aspect of the present invention, there is provided an off-line teaching method for a machining robot, wherein a planar image of a workpiece is displayed on an image display means to teach an operation of the machining robot. Wherein the processing robot is a cutting processing robot,
(A) displaying, on the image display means, a two-dimensional CAD image of the workpiece including a shape to be cut, which is input by the two-dimensional CAD; and (b) displaying the shape to be cut on the two-dimensional image. Specifying a cutting line along the cutting line, and (c) specifying a cutting condition having a groove angle, a root face, and a cutting width in cutting along the cutting line,
(D) Including the attitude of the end effector of the machining robot
Teaching data activity on the non-three-dimensional space, wherein step (b)
And a step of creating based on the cutting line specified in the step (c) and the cutting condition specified in the step (c).

According to a third aspect of the present invention, there is provided the offline teaching method for a machining robot according to the second aspect , wherein the step (d) is performed in the offline teaching method for a machining robot according to the second aspect.
(D-1) a step of creating the teaching data so that a target position of the end effector in the center axis direction of the end effector is located on the surface of the workpiece.

[0009]

[0010]

According to the first aspect of the present invention, in the offline teaching method for a machining robot, pattern data relating to the three-dimensional operation of the end effector which needs to be designated is created and registered in advance, and the plane of the workpiece is displayed on the image display means. The teaching is performed by displaying an image, designating the registered pattern data, and designating a reference point of the pattern data on the planar image to designate a position required by the pattern data.

[0011] In off-line teaching method of processing robot according to claim 2 and 3 in the present invention, displaying the plane image of the workpiece on the image display unit, the cutting line specified on the plane image, open associated with cut line above angle, by entering the cutting conditions such as the root face, the figure of the end effector
Teaching of complicated three-dimensional movement including force .

According to a third aspect of the present invention, the offline teaching method for a machining robot is most suitable for cutting the target position of the end effector in the center axis direction based on the taught cutting line and cutting conditions. Cutting at the position on the surface of the work, which is the right position.

[0013]

【Example】

[Schematic Configuration of Cutting Robot and Its Teaching Device] FIG.
1 is a schematic perspective view showing a configuration of a cutting robot system for performing a three-dimensional cutting of a plate-shaped work by applying the present invention. The cutting robot RB includes columns 2a, 2a vertically set on two bases 1a and 1b, respectively.
In addition, a beam 3 is erected on the top of the columns 2a and 2b, and a rail 4 is provided on the beam 3. A left and right moving body 5 is mounted on the rail 4 and can move in the T1 direction along the rail 4. One end of each of the two arms 6a, 6b is rotatably supported by the left and right moving body 5, and the other end of each of the arms 6a, 6b rotatably supports the head 7, and the arms 6a, 6b Maintain a parallel positional relationship with each other. The arms 6a and 6b rotate in a direction indicated by α3 around a fulcrum supported rotatably by the left and right moving body 5, and with this rotation, the head 7 moves up and down and back and forth while keeping its posture constant. Moving.

The head 7 rotatably supports the arm 8 so as to rotate in a direction α1 about a vertical axis. Similarly, the arm 8 rotatably supports the arm 9 so as to rotate in the α2 direction about a vertical axis. The arm 9 is rotatably supported so that the arm 10 rotates around a vertical axis in the α4 direction. Further, a torch 11 as an end effector is rotatably supported on the arm 10 so as to rotate in a direction α5 around a horizontal axis. Movement in the T1 direction,
The rotations in the directions α1 to α5 are all driven by a motor (not shown).

A combustible gas and an oxygen gas are delivered to a torch 11 by a flexible gas pipe 12. In the vicinity of one end of the beam 3, an ignition device 13 that constantly blows a flame for igniting a pilot flame on the torch 11 is provided. Motor for driving the movement in the T1 direction and the rotation in the α1 to α5 directions, and the cutting robot RB for controlling the amount of gas sent to the torch, etc.
Is controlled by the robot control panel 14. The robot control panel 14 has six axis coordinate values T1, α1 to α5,
In addition, teaching data relating to the amount of gas sent to the torch is stored, and the operation of the torch 11 is controlled according to the teaching data. The work to be cut is fixedly mounted on a work mount (not shown) located in front of the beam 3 so that the work is located within the movable range of the torch 11.

A personal computer 15 as an offline teaching device is connected to the robot control panel 14. This personal computer 15 has a CRT 16,
A keyboard 17, a mouse 18, a hard disk 19, a printer 20, and the like are provided. The operator first
Using this personal computer 15, teaching data is created without operating the cutting robot RB body, and the created teaching data is transferred to the robot control panel 14 and stored.

[Schematic Procedure of Operation of Cutting Robot RB] FIG. 3 shows a cutting robot R based on the teaching data.
6 is a flowchart showing a schematic procedure of the operation of B. First, preprocessing is performed in step S1. That is, torch 1
1 moves from the standby position to the ignition device 13, and the flammable gas is sent to the torch 11 at a relatively small rate. This allows
A pilot flame ignites on the torch 11. Subsequently, the torch 11 moves to a position where the next step S2 is started.

In step S2, sensing for detecting the position of the work is performed. FIG. 4 is a schematic diagram showing a schematic configuration of a device for performing sensing. The torch 11 is provided with a conductive probe 22 such that the tip is located at a point corresponding to a target position for cutting in the flame 21 blown out from the tip. An energizing path 23 is provided between the probe 22 and the work W, and a voltage source 24 for applying a voltage between the probe 22 and the work W is provided in the energizing path 23.
And a detector 25 for detecting the energization along the energization path 23 is inserted. When the tip of the probe 22 comes into contact with the workpiece W, a current flows through the power supply path. The detector 25 detects this current. When performing sensing, the torch 11 is moved near the work W so that the tip of the probe 22 appropriately contacts the work W. At this time, the position of the work W is detected from the position of the torch 11 when the power is detected by the detector 25.

The teaching data defining the operation of the torch 11 in the cutting operation and other steps in step S4 described later is corrected based on the information on the position of the work W obtained by the sensing performed in step S3. You. That is, as a result of the sensing, if a deviation is found between the mounting position of the work W and the mounting position of the work W assumed by the teaching data, the coordinates defining the position and orientation of the torch 11 in the teaching data to correct the deviation. Modify the value. Thus, it is possible to prevent an erroneous cutting operation due to an error in the mounting position of the work W.

In step S3, an approach operation is performed.
That is, the torch 1 is moved to the point where the cutting of the workpiece W is started.
1 and preheating the work W at the cutting start point. Further, before starting the cutting along the first cutting line, the torch 11 is moved so as to be smoothly introduced to the starting point of the cutting in order to smooth the finish of the cutting at the starting point of the cutting. Thereafter, the process proceeds to step S4.

In step S4, a cutting operation is performed along one cutting line of the work W. The cutting line is made up of a straight line or an arc. In step S4, cutting is performed along one straight line or one arc.

In step S5, it is determined whether or not another cutting line is to be cut. If all cutting along the cutting line of the workpiece W has been executed, it is determined that there is no other cutting line to be cut anymore, and the process proceeds to step S8. Conversely, if there is still a cutting line that has not been cut from the workpiece W, it is determined that another cutting line is to be cut, and the process proceeds to step S6.

In step S6, it is determined whether or not to perform a corner process. When corner processing is not required, such as when the cutting line that has been cut last and the cutting line to be cut next are smoothly connected, the process proceeds to step S4 and the next cutting line is performed without performing corner processing. Perform cutting along. Conversely, if corner processing is required, step S
Move to 7.

In step S7, a corner process is performed. That is, in addition to cutting along the cutting line, extra cutting is performed near the connecting point so that the finish of the cutting at the connecting point of the two cutting lines becomes smooth. When the corner processing is completed, the process proceeds to step S4, and cutting is performed along the next cutting line.

At step S8, an escape operation is performed. That is, after the cutting along the last cutting line is completed, the torch 11 is moved so as to be smoothly separated from the last cutting point in order to smooth the finish of the cutting at the last cutting point. Thereafter, the process proceeds to step S9.

In step S9, post-processing is performed. That is, the torch 11 is moved to a predetermined standby position to extinguish the pilot flame.

[Schematic Procedure of Teaching] FIG. 1 shows a robot control panel 1 in which teaching data for defining the operation of the torch 11 is created.
4 is a flowchart illustrating a schematic procedure of a teaching operation that includes a content to be transferred to No. 4; The creation of the teaching data is performed using the personal computer 15 shown in FIG.

First, in step S11, it is determined whether to newly create pattern data or to modify already registered pattern data. If the already registered pattern data is to be used as it is, the process directly proceeds to step S13 because it is not any of the above. Conversely, when creating new pattern data or modifying already registered pattern data, the process proceeds to step S12. Here, the pattern data refers to a series of operations in a three-dimensional space of the end effector (the torch 11 in this example) of the cutting robot RB at each stage of the cutting, as will be described later in detail with reference to an actual example. This is registered in advance and is quoted at the stage of teaching the operation procedure of the cutting robot RB, and is related to the gist of the present invention.

In step S12, pattern data is created or corrected. The pattern data is individually created or corrected for each stage of the cutting process, that is, for each step in the flowchart of FIG. The pattern data is created using a three-dimensional CAD, or a cutting robot R
This is executed by a teaching playback method in which a skilled technician teaches while operating the torch 11 of B. In this process, the complicated movement of the torch 11 that requires advanced skill and belongs to the so-called technical know-how can be included in the pattern data.

The created or modified pattern data is registered. That is, the storage device of the personal computer 15, for example, the hard disk 1
9 together with a name that can be distinguished from other pattern data. When the work of creating or modifying necessary pattern data and registering it is completed, the process proceeds to step S13.

In step S13, graphic data relating to the shape of the workpiece W and the shape of the cutting line to be cut is created. A system for creating two-dimensional graphic data using a computer is used to create these graphic data.
Use dimensional CAD. More specifically, a commercially available two-dimensional C
The graphic data is created by incorporating (installing) the AD software into the personal computer 15. The shape of the cutting line is expressed as a set of straight lines or circular arcs. Creation of two-dimensional graphic data by two-dimensional CAD can be performed much easier than creation of three-dimensional graphic data by using three-dimensional CAD. One of the advantages of the present invention is that two-dimensional graphic data easily created by two-dimensional CAD is sufficient for graphic data to be prepared for performing a cutting operation in a three-dimensional space. . When the creation of the graphic data is completed, the process proceeds to step S14.

In step S14, the cutting robot R
The operation procedure of B is taught. Personal computer 15
The two-dimensional CAD graphic created in step S13 is displayed on the CRT 16 attached to, and points are appropriately designated on the two-dimensional CAD graphic, and necessary pattern data is appropriately selected from registered pattern data. To specify the procedure related to the three-dimensional operation of the cutting robot RB. The groove angle, root face, cutting width, etc. in the cutting work are also specified at the same time. These designations can be easily executed by inputting these numerical values using the keyboard 17. Along with this point, as described above, a series of three-dimensional operations of the cutting robot RB are registered in advance as pattern data, and teaching is performed by referring to the pattern data. It is possible to easily teach a procedure relating to a complicated three-dimensional operation of the cutting robot RB on a two-dimensional CAD figure.

Along with the operation in step S14, teaching data for defining the operation of the cutting robot RB is created in a predetermined storage area of the hard disk 19 attached to the personal computer 15. This teaching data is
Expressed in coordinates (work coordinate system) relative to the work W,
Instruct the target position and direction of the torch 11 in order,
It is a series of signals. When teaching is completed, the operation proceeds to step S
Move to 15.

In step S15, the teaching data in the work coordinate system is converted into the teaching data in the NC format. At this time,
Enter the relationship between the work coordinate axis and the NC coordinate axis. That is, an NC coordinate value expressing a position and an orientation in one axis of the work coordinate system, for example, the NC coordinate system of the x-axis is input by operating the keyboard 17.

The teaching data in the NC format expresses the target position and orientation of the torch 11 in five degrees of freedom coordinates (NC coordinate system) relative to the main body of the cutting robot RB. The teaching data in the NC format expressed in the NC coordinate system is expressed in a format that is not limited to the robot model and has a character as a common language among various robots. Therefore, there is an advantage that once the teaching data is converted into the NC format and stored in some storage medium, it can be applied to various kinds of cutting robots. Upon completion of the conversion of the teaching data, the process proceeds to step S16.

In step S16, the teaching data is converted into teaching data in the robot coordinate system. The robot coordinate system is generally a coordinate that defines the position and orientation of the end effector with reference to a coordinate axis specific to the type of the robot. In the cutting robot RB shown in FIG. T1, α1 to α specified in degrees
5 means 6 variables. In step S16, the teaching data in the NC format is used to determine the operation of the torch 11 as T1, α1.
It is converted into teaching data in a robot coordinate system expressed by six variables of? 5. If there is no need to use the teaching data in the NC format, step S15 does not need to be executed,
The process may shift directly from step S14 to step S16 (dotted line in FIG. 1). In this case, in step S16, the teaching data in the work coordinate system is directly converted into the teaching data in the robot coordinate system. When the conversion into the teaching data in the robot coordinate system is completed, the process proceeds to step S17.

In step S17, the teaching data in the robot coordinates is transferred to the robot control panel 14 and stored. Thus, the teaching operation is completed.

[Example of Creating Pattern Data] An example of the pattern data created in step S12 will be described below.

<Pattern Data of Pre-Processing> FIG. 5 shows an example of pattern data of the pre-processing (step S1). The pattern data of the preprocessing is expressed in the NC coordinate system. The three axes (X, Y, Z) depicted in FIG. 5 are coordinate axes in the NC coordinate system. The relationship between the NC coordinate system and the robot coordinate system is as follows. For example, the Z axis of the NC coordinate system matches the upward direction of the cutting robot RB, the X axis of the NC coordinate system matches the T1 direction of the robot coordinate system, and the NC coordinate system Correspond to the direction from the beam 3 of the cutting robot RB toward the front where the torch 11 is located. The work W has a plate-like shape and is mounted, for example, at a position of about Z = 0 so that its main surface is horizontal and within a range of Y> 0. In FIG. 5, the torch 1
The position and orientation of 1 are represented by a cone for convenience (the same applies to the following figures). The tip of the cone represents a target position for cutting in the flame 21 ejected from the torch 11. The direction from the bottom of the cone toward the tip is the direction in which the flame 21 blows out.

The torch 11 is initially located at the point P1 which is a standby position. The point P1 is, for example, when the torch 11 is at the center of the beam 3 and is sufficiently away from the workpiece W (for example, 1000
mm) (2500, 0, 1000) located above.
The coordinate values are coordinate values in the NC coordinate system, and are expressed in millimeters (mm). Next, the torch 11 moves horizontally to the point P2, which is a position directly above the ignition device 13. The point P3 which is the position of the flame of the ignition device 13 is, for example, at the position (5000, 0, 0). When the torch 11 reaches the point P2, it descends toward the point P3, and when the torch 11 reaches the point P3, the supply of the flammable gas to the torch 11 is started. Thus, a pilot flame is ignited on the torch 11. At this time, the supply rate of the combustible gas is a relatively small rate. Next, the torch 11 returns from P3 to P2, further returns to the point P1, and then moves to the next step, that is, the point P4 which is the start position of sensing (step S2).

The coordinate value of the point P4 is not specified by a specific numerical value but is given by a variable. When the teaching data is converted to the teaching data in the NC coordinate system in step S15, or when the teaching data is converted to the teaching data in the robot coordinate system in step S16, the pattern data of the preprocessing and the preprocessing are performed. Is combined with the sensing pattern data that follows, and at this time, a specific numerical value of the sensing pattern data is substituted for the variable.

<Sensing Pattern Data> FIG. 6 shows an example of sensing (step S2) pattern data. The operation position is determined based on two reference points B11 and B12 located on a plane defined by z = 0 in the work coordinate system (x, y, z). Reference points B11, B12
Are given while teaching the operation procedure of the cutting robot RB in step S14. Torch 11
(Accurately, the target position in the flame 21. The same applies to the following.) A point P11 which is an initial position is, for example, on the z-axis from a point 50 mm away from B11 on an extension line extending from the reference point B12 to B11. It is a position 10mm away in the forward direction. This point P1
1 is the same position as the point P4, and the coordinate value of the point P11 is given as the coordinate value of the point P4 in step S15 or S16 as described above.

At the initial position P11, the torch 11
First, in a plane parallel to the z-axis and including the reference points B11 and B12, an orientation is selected in a direction at 45 degrees to the z-axis as shown in FIG. Next, the torch 11 moves from the initial position P11 toward the point P12. Point P12 is a reference point B11
10mm from the reference point B12 on the extension from B12 to B12
The position is further away from the distant position by 10 mm in the positive direction of the z-axis. When the torch 11 reaches the point P12, z
It moves toward point P13 which is 20 mm away in the negative direction of the axis.
In this process, the current is detected by the detector 25 and the probe 2
When it is found that the workpiece 2 has come into contact with the work W, the coordinate value corresponding to the position of the torch 11 at that time is stored, and the torch 11 reverses the moving direction and returns to the point P12.
When returning to the point P12, it moves toward the point P14. Point P
Reference numeral 14 denotes a position on the extension line extending from the reference point B12 to B11, at a position 10 mm away from a point 40 mm away from B11 in the positive direction of the z-axis, and located on a line connecting the points P11 and P12. When the torch 11 reaches the point P14, the torch 11 moves toward the point P15 which is 20 mm away from the point P14 in the negative direction of the z-axis. When the torch 11 reaches the point P15, it moves toward the point P13. During the movement from the point P15 to the point P13, if it is found that the power is detected by the detector 25 and the probe 22 has come into contact with the workpiece W, the coordinate value corresponding to the position of the torch 11 at that time is stored. At the same time, the torch 11 reverses the moving direction and returns to the point P15. Further, the process returns from the point P15 to the point P14, and then moves to a next step, for example, a point P16 which is a start position of the approach operation (step S3).

The coordinate value of the point P16 is not defined by specific numerical values as in the case of the point P4, but is given by a variable. When the teaching data is converted to the teaching data in the NC coordinate system in the above-described step S15, or when the teaching data is converted to the teaching data in the robot coordinate system in the step S16,
The pattern data of the sensing and the pattern data of the next step are combined, and at this time, a specific numerical value of the pattern data of the next step is substituted for the variable.

By the above operation, the position of the work W in the z direction and the position of the line segment connecting the two reference points can be detected. In the sensing process (step S2), not only is the sensing pattern data executed once,
By setting a plurality of pairs of reference points, it is also possible to execute sensing pattern data a plurality of times, whereby the position of the work W can be completely grasped. Also, the above-described sensing pattern data is merely an example, and any number of other sensing pattern data can be prepared.

<Pattern Data of Approach Operation> FIG.
Is an example of the pattern data of the approach operation (step S3). In the work coordinate system (x, y, z), z =
Two reference points B21 located on a plane defined by 0
The position of the operation is determined based on B22. Reference point B2
1, the coordinate values of B22 are given while teaching the operation procedure of the cutting robot RB in step S14. The reference point B22 coincides with the starting point of the cutting operation (step S4) following the approach operation (step S3). Torch 1
The point P21 which is the initial position of No. 1 is, for example, a reference point B2
This is a position 20 mm away from a point 50 mm away from B21 on the extension line extending from 2 to B21 in the positive direction of the z-axis. This point P21 is at the same position as the above-mentioned point P16 in the sensing pattern data cited last, and the coordinate value of the point P21 is given as the coordinate value of the point P16 in step S15 or S16 as described above.

The torch 11 is moved from the initial position P21 to a point P2.
Move toward 2. Point P22 is B from reference point B22.
It is a position 20 mm away from the reference point B 21 on the extension line extending to 21. When the torch 11 reaches the point P22, it goes to the reference point B22 via the reference point B21. When the torch 11 reaches the reference point B22, it temporarily stops. During this temporary stop, the vicinity of the cutting start point of the work W is preheated by the seed flame of the torch 11. After the torch 11 has been stopped for a certain period of time, the supply rate of the combustible gas supplied to the torch 11 is increased, and oxygen gas is supplied. Thus, the flame 21 ejected from the tip of the torch 11 becomes an oxygen flame that can cut the work W. At the reference point B22, the ejection of the oxygen flame is started, and the approach operation ends. The pattern data of the approach operation is not limited to the above example, and a plurality of types of pattern data can be prepared.

While teaching the operation procedure of the cutting robot RB in step S14, as will be described later, a groove angle, a root face, and a cutting width at the time of cutting are specified, but based on these specified values. Thus, the pattern data of the approach operation is corrected. The direction of the torch 11 is determined by giving a designated value of the groove angle. FIG. 7 illustrates a case where the designated value of the groove angle is zero. These will be described in detail when describing FIG.

<Pattern Data of Corner Processing> FIG. 8 shows an example of pattern data of the corner processing (step S7). An operation position is determined based on one reference point B31 located on a plane defined by z = 0 in the work coordinate system (x, y, z). The coordinate value of the reference point B31 is given while teaching the operation procedure of the cutting robot RB in step S14. The reference point B31 coincides with the end point of the cutting (step S4) along one cutting line L31 and the starting point of the cutting (step S4) along the next cutting line L32. In the corner processing, the reference point B31 is a start point and an end point.

In the corner processing, the torch 11 continues to emit the same oxygen flame as in the cutting (step S4). First, the torch 11 is moved from the reference point B31 to the cutting line L3.
It moves by a distance of 20 mm along a tangent line at one reference point B31. Next, the torch 11 moves so as to draw an arc around the reference point B31, and moves along the reference point B31 of the cutting line L32.
When the point P33 on the tangent at is reached, it moves toward the reference point B31 along this tangent. When the torch 11 reaches the reference point B31, the corner processing ends. The direction of the tangent is determined by L31 and L32. In the above step S15, the teaching data is N
When the teaching data is converted into the teaching data in the C coordinate system, or when the teaching data is converted into the teaching data in the robot coordinate system in step S16, the teaching data of the cutting processing prior to the corner processing and the teaching data subsequent to the corner processing. The teaching data of the cutting process is combined with the teaching data of the corner process. At this time, the calculation is executed by the personal computer 15 and the direction of the tangent is determined from the data of L31 and L32.

The pattern data of the corner processing is the same as the above 1
Not only examples but also a plurality of types of pattern data can be prepared. In teaching the operation procedure of the cutting robot RB in step S14, the pattern data of the corner processing is corrected based on the specified groove angle, root face, and cutting width at the time of cutting. The direction of the torch 11 is determined by giving a designated value of the groove angle. FIG. 8 illustrates a case where the designated value of the groove angle is zero. These will be described in detail when describing FIG.

<Pattern Data of Escape Operation> FIG. 9 shows an example of pattern data of the escape operation (step S8).
An operation position is determined based on two reference points B41 and B42 located on a plane defined by z = 0 in the work coordinate system (x, y, z). The coordinate values of the reference points B41 and B42 are given while teaching the operation procedure of the cutting robot RB in step S14. The reference point B41 is a cutting operation (step S8) immediately before the escape operation (step S8).
It matches the end point of 4).

The torch 11 reduces the supply rate of the combustible gas at the reference point B41 and stops the supply of the oxygen gas. As a result, the torch 11 stops blowing the oxygen flame,
It shifts to the ejection of a seed flame with relatively weak thermal power. Torch 1
1 further moves from the reference point B41 toward the reference point B42, passes through the reference point B42, and then moves from the reference point B41 to B
Move further on the extension to 42, 20mm from the reference point B42
When it reaches the point P41 located at the distance of, it moves toward the point P42. The point P42 is located at a distance of 50 mm from the reference point B42 on the extension line from the reference point B41 to B42.
It is a position 20 mm away in the positive direction of the z-axis. When the torch 11 reaches the point P42, the escape operation ends.

The pattern data of the escape operation is not limited to the above example, and a plurality of types of pattern data can be prepared. In step S14, the cutting robot R
In teaching the operation procedure of B, correction is made to the pattern data of the corner processing based on the specified groove angle, root face, and cutting width at the time of cutting. The direction of the torch 11 is determined by giving a designated value of the groove angle. FIG. 9 illustrates a case where the designated value of the groove angle is zero. These will be described in detail when describing FIG.

<Pattern Data of Post-Processing> FIG. 10 shows an example of pattern data of post-processing (step S9). The post-processing pattern data is expressed in the NC coordinate system. FIG.
Three axes (X, Y, Z) drawn at 0 are coordinate axes in the NC coordinate system.

The point P51 corresponds to a point P42 which is the end point of the immediately preceding process, ie, the escape operation (step S8). The torch 11 linearly moves from the point P51 to a point P52 which is a standby position of the torch 11. The point P52 is, for example, at the same position as the point P1 in FIG. 5, that is, (2500, 0, 1000) in the NC coordinate system.

The coordinate value of the point P51 is not specified by a specific numerical value but is given by a variable. When the teaching data is converted into teaching data in the NC coordinate system in step S15 described above,
Alternatively, when the teaching data is converted into teaching data in the robot coordinate system in step S16, the escape operation pattern data and the post-processing pattern data following the escape operation are combined, and at this time, the escape The coordinate value of the point P42 included in the operation pattern data is substituted.

[Operation of Torch 11 During Cutting] FIG.
FIG. 4 is an operation explanatory diagram for explaining the operation of the torch 11 at the time of the upper groove cutting. In step S14, when teaching the operation procedure of the cutting robot RB, the teaching point (T1, T2, T3...) Corresponding to the end of the cutting line is designated to specify the cutting line (L1, L2, L3). ...). At the same time, the numerical values of the groove angle θ, the root face r, the thickness d of the work W, and the cutting width w are taught. In the example shown in FIG. 11, the cutting line L1 is a straight line, and the cutting lines L2 and L3 are arcs. Each cutting line is smoothly connected at the teaching point. Based on such teaching data, the torch 11 operates as shown by a cone in FIG. That is, the torch 11 has lines M1, M2, M on the main surface PS1 of the work W whose target positions are separated from the cutting lines L1, L2, L3.
3 and the central axis Ax is represented by lines M1, M2, M3
.. Are always perpendicular to each other and form an angle θ with respect to the normal line of the main surface PS1 of the work W. The distance d1 is given by Expression 1.

[0059]

(Equation 1)

Thus, the cut surfaces C1, C2, C3,... Having the specified groove angle θ and the root face r.
Is realized. Moreover, the cutting can be performed while maintaining the target position of the torch 11 in the direction of the central axis Ax on the surface of the work W which is the optimum position for performing the effective cutting.

FIG. 12 shows the torch 11 at the time of lower groove cutting.
FIG. 4 is an operation explanatory diagram for explaining the operation of FIG. As in the case of teaching the upper groove cutting, when teaching the operation procedure of the cutting robot RB in step S14, a teaching point (T11, T12, T13...) Corresponding to the end of the cutting line is designated. The cutting lines (L11, L12, L13
At the same time, the numerical values of the groove angle θ, the root face r, the thickness d of the work W, and the cutting width w are taught. The shape of the cutting line in the example shown in FIG.
11 is a straight line, and the cutting lines L12 and L13 are circular arcs. Each cutting line is smoothly connected at the teaching point. Based on such teaching data, the torch 11 operates as shown by a cone in FIG. That is, the torch 11 always has the cutting lines L11, L12, L13.
Are perpendicular to... And form an angle θ with the normal to the main surface PS1 of the work W, and the target position is the cutting line L11, L12, L1.
The main surface P of the work W separated by a distance d2 from 3 ...
Positions further moved from the lines N11, N12, N13... On the extension surface of S1 along the axis Ax toward the tip of the torch 11 with a distance s, that is, cutting lines L11, L1.
2, L13..., The edge surface PS2 of the workpiece W forming a distance t
It operates so as to follow the upper lines M11, M12, M13. The distances d2, s, and t are given by Equations 2, 3, and 4, respectively.

[0062]

(Equation 2)

[0063]

(Equation 3)

[0064]

(Equation 4)

Thus, the cut surfaces C11, C12, C13 having the specified groove angle θ and the root face r
... is realized. Moreover, the torch 1 in the central axis Ax direction
The cutting can be performed while maintaining the first target position on the surface of the work W which is the optimum position for performing the cutting effectively.

[Example of Teaching Process] In the following, in order to perform the work of cutting the workpiece W according to one example, step S1 is performed.
The step of teaching the operation of the cutting robot RB in 4 will be described. FIG. 13 is an image displayed on the screen S of the CRT 16 at the final stage of teaching. FIG. 14 is a list of sets of teaching data that are input for each teaching stage and displayed in the lower column of the CRT 16.

<Display on the screen of the CRT 16> In order to teach the operation of the cutting robot RB in step S14, graphic data created using two-dimensional CAD in step S13 before that is used. On the screen S, a plan view of a flat work W is shown as shown in FIG. At the four corners of the area for displaying the work W on the screen S, coordinate values in the work coordinate system are displayed. The coordinate axes x and y displayed on the screen S represent the coordinate axes of the work coordinate system. That is, the coordinate axes x and y of the work coordinate system are the work W
And z is perpendicular to the main surface.

The position of the cursor CS can be freely changed on the screen S by operating the mouse 18. By moving the cursor CS to the position where the coordinate value is displayed and clicking a button (not shown) of the mouse 18, the coordinate value can be changed. In this state, a numerical value is input by using the keyboard 17. The coordinate values of the four corners can be easily changed. That is, by operating the keyboard 17 and the mouse 18, the screen S
The scale on the work coordinate system can be easily changed. In the example of FIG. 13, the width of the area for displaying the work W on the screen S is 300 mm, and the vertical width is 200 mm. In the area below the screen S, a set of teaching data input in one stage of teaching is displayed.

In this example, regarding the plate-shaped work W displayed on the screen S, lines L41, L42 and L sandwiched by lines on the right edge of the work W, ie, points 4 to 7
Using 43 as a cutting line, groove angle 30 °, root face 5m
Teaches upper groove cutting with m and cutting width 0. First, the thickness of the work W is input as 10 mm by operating the keyboard 17.

<Teaching of Sensing> Subsequently, the cursor CS is moved to instruct the display "step" at the lower left of the screen S, and the mouse 18 is clicked here to indicate the first teaching step. Is ready for inputting the data set. At this time, 1 is displayed as a step number in the column below the display "step" (the row of step 1 in FIG. 14). This step number is an index for identifying each stage in teaching, and at the same time, the cutting robot R
B corresponds to the order of the steps performed. Step 1, that is, a set of teaching data in the first teaching stage is input as shown in the row of step 1 in FIG. First, cursor C
After instructing "No" on the screen S in S, the mouse 18 is clicked. At this time, the user can enter a numerical value in the lower column of “No”, and operates the keyboard 17 to input a numerical value “1”.
Enter “No” means a point number.

Subsequently, the cursor CS is moved on the screen S, and the position of the point with the point number 1 on the screen S (abbreviated as point 1; the same applies hereinafter) is designated. The x-coordinate value and the y-coordinate value of the position indicated by the cursor CS are displayed in the lower columns of “X” and “Y” on the screen S, respectively, as the cursor CS moves on the screen S. Also changes. The mouse 18 is clicked after the cursor CS is appropriately moved so that the coordinate value becomes (120.0, 20.0). As a result, as shown in FIG. 13, a black circle is displayed on the screen S at a position corresponding to the coordinate value, and "1" is displayed near the black circle at the same time. “X” and “” on screen S
In the lower column of Y ", the determined coordinate value of point 1 is displayed.

Next, "processing" on the screen S is
Instruct by S and click the mouse 18. Then, screen S
Displays a list of registered pattern data names (not shown). On this list display, for example, the third pattern data is selected from a plurality of registered sensing pattern data. That is, the cursor CS
Is clicked with the mouse after indicating the name of the corresponding pattern data. Then, the list display disappears from the screen S, the original image appears, and “Process” is displayed in the lower column.
At this time, the "reference point" is displayed in the lower column of the "mode." That is, since the sensing pattern data is selected as the pattern data, the point 1 is automatically set as the reference. In this case, it is assumed that the third pattern data of the selected sensing is the above-described pattern data shown in FIG.

As described above, the data set input at the teaching stage of step 1 is as shown in the row of step 1 in FIG. When the sensing pattern data is selected, it is not necessary to input conditions such as a groove angle, a cutting width, a route face, and a moving speed of the torch 11. Therefore, the lower columns of “groove”, “cut width”, “root”, and “condition” are left blank or a symbol of input prohibition (FIG. 1).
The symbol "-" in 4 is displayed.

Next, a set of teaching data is input in step 2 which is the second teaching stage. First, the cursor CS
Is clicked, and the mouse 18 is clicked. As a result, the display in the lower column of “Step” is changed to “2”.
Changes to Thereafter, in the same manner as above, a data set is input as shown in the row of step 2 in FIG. Since the third pattern data for sensing is selected in step 1 and step 2, point 1 taught in step 1 and point 2 taught in step 2 correspond to reference points B11 and B12 in FIG. 6, respectively. Can be The smaller point number, that is, point 1 is associated with the reference point B11. That is, as the coordinate values of the reference points B11 and B12, the points 1 and
The coordinate value of point 2 is substituted. Point 2 which is a second reference point at the time of sensing is set on the contour of the work W.

<Teaching of Approach Operation> Next, in steps 3 and 4, which are the third and fourth teaching stages, an approach operation is taught. The display in the lower column of the screen S at the end of the input in each step is as shown in each row of steps 3 and 4 in FIG. In steps 3 and 4, the pattern data of the approach operation is selected as the pattern data. For example, the second pattern data is selected from various registered pattern data of the approach operation. As a result, in the lower column of “processing” of the screen S, “
Approach 2 "is displayed. Here, it is assumed that the second pattern data of the selected approach is the above-described pattern data shown in FIG.

In steps 3 and 4, points 3 and 4 are taught as shown in FIG. Points 3 and 4 are respectively associated with reference points B21 and B22 in FIG.
The smaller step number, that is, the point 3 taught in step 3, is associated with the reference point B21. That is, the coordinate values of point 3 and point 4 are substituted for the coordinate values of reference points B21 and B22, respectively. Since the reference point B22 is a cutting start point, as shown in FIG.
41 is taught at the lower right corner on the contour of the work W, which is one end point of the work W and is a cutting start point of the work W. The reference point B21 is a point that determines the direction approaching the first cutting line. Torch 11
Desirably smoothly approaches the cutting line, and therefore, the position of the reference point B21 is preferably determined so that the reference point B21 is located on a tangent to the cutting start point of the cutting line L41 to be cut first. Therefore, point 3 should be taught on an extension of L41 which is a cutting line to be cut first in FIG. Since the pattern data of the approach operation is selected as the pattern data, "reference point" indicating that point 3 or point 4 is automatically regarded as the reference point is displayed in the lower column of "mode". .

Since the pattern data of the approach operation is selected as the pattern data, conditions such as a groove angle, a cutting width, a root face, and a moving speed of the torch 11 are also input. In order to improve the finish of the cut surface at the cutting start point, it is preferable that these input data be the same as the input data in the cutting process. Therefore, the groove angle is 30.0 degrees, the cutting width is 0.0 mm, and the root face is 5.0 mm
Enter In order to input these numerical values, for example, "groove" is indicated by the cursor CS, the mouse 18 is clicked, and then the numerical value 30.0 is input by the keyboard 17.
The procedure is as follows. If the numerical value input in the lower column of “groove” is positive, it means upper groove cutting, and if negative, it means lower groove cutting. Therefore, in this example, the upper groove cutting at a groove angle of 30 degrees is taught.

The robot control panel 14 stores a torch 11 of a different type from the teaching data created and transferred by the personal computer 15 in a storage device (not shown) in the robot control panel 14.
Control data relating to the operation of. This is a set of signals indicating the moving speed of the torch 11, the supply rate of the flammable gas, the supply rate of the oxygen gas, and the like. Several sets are prepared, and one can be selected from among them. it can.
By inputting a number in the lower column of “condition” on the screen S, each one of these sets is selected. In this example, for example, a set corresponding to the number “6” is designated, and thus “6” is displayed in the lower column of “condition”. The method of inputting the number in the lower column of “condition” is the same as the method of inputting the numerical value of the lower column such as “groove”.

<Teaching of Cutting along First Cutting Line> Next, in step 5, which is a fifth teaching stage, a cutting operation along the first cutting line L41 is taught. Step 5
The display in the lower column of the screen S at the time when the input in step S is completed is as shown in the row of step 5 in FIG.

First, as shown in FIG.
The point 5 is taught at the position of the cutting end point. Next, cutting is selected as the type of processing. As a result, "
"Disconnect" is displayed in the lower column of "Process." At this time, "Line segment" is displayed in the lower column of "Mode" on the screen S. In step 5, disconnection is selected as the type of process. Therefore, point 5 taught in step 5 and step 5
L41 connecting point 4 taught in step 4 immediately before
Is regarded as a cutting line. Since the cutting line L41 is input as a straight line using the two-dimensional CAD in the previous step S13, the cutting line L4 is displayed in the lower column of the “mode” of the screen S.
"Line segment", which means that 1 is a straight line, is displayed as described above.

The teaching data of the cutting created by the teaching has a content instructing the torch 11 to perform the cutting operation as shown in FIG. 11 or FIG. Since cutting is selected as the type of processing, conditions such as a groove angle, a cutting width, a root face, and a moving speed of the torch 11 are also input. That is, 30.0 degrees, a cutting width of 0.0 mm, and a root face of 5.0 mm are input as the groove angle. As in the teaching of the above-described approach operation, a set of the control data such as the moving speed of the torch 11 corresponding to the number “6” is designated. Therefore, “6” is displayed in the lower column of “condition”.

<Teaching corner processing> First cutting line L4
1 and the subsequent second cutting line L42 are not smoothly connected at point 5, which is the connection point. Therefore, after the cutting of the cutting line L41 is completed, the cutting line L42
If the cutting is continuously performed as it is, there is a possibility that the finish of the cut surface at the connection point 5 may be in a defective state.
In order to avoid this, it is desirable to perform corner processing at point 5. In particular, when the groove angle is not zero, the need for corner processing is high. Therefore, in step 6, which is the sixth teaching stage, the pattern data of the corner processing is selected as the pattern data. The display in the lower column of the screen S at the time when the input in step 6 is completed is shown in FIG.
As shown in the row of step 6 of FIG.

First, a numerical value “
5 "is input. Next, 1 is selected from the pattern data of the corner processing in which a plurality of types are registered as the pattern data. For example, the pattern data of the third corner processing is selected. As a result, the screen is displayed. "Processing" of S
"Corner 3" is displayed in the lower column. At the same time, a "reference point" is displayed in a lower column of "mode" on the screen S. That is, it is displayed that the point 5 is automatically regarded as the reference point because the pattern data of the corner processing is selected as the pattern data. Here, it is assumed that the third pattern data of the selected corner process is the above-described pattern data shown in FIG. Therefore, the point 5 is associated with the above-described reference point B31, and the coordinate value of the point 5 is substituted as the coordinate value of the reference point B31.

Since the pattern data of the corner processing is selected as the pattern data, conditions such as a groove angle, a cutting width, a root face, and a moving speed of the torch 11 are also input. That is, the groove angle is 30.0 degrees, the cutting width is 0.0 mm,
Enter the root face 5.0mm. Also, as in the teaching of the cutting operation described above, a set of the control data such as the moving speed of the torch 11 corresponding to the number “6” is designated.
Therefore, “6” is displayed in the lower column of “condition”.

<Teaching of Cutting Along Second Cutting Line> Next, in step 7, which is a seventh teaching stage, a cutting operation along the second cutting line L42 is taught. Step 7
The display in the lower column of the screen S at the end of the input in step S is as shown in the row of step 7 in FIG.

First, as shown in FIG.
The point 6 is taught at the position of the cutting end point. Next, cutting is selected as the type of processing. As a result, “Disconnect” is displayed in the lower column of “Process” on the screen S, and at the same time,
In the lower column of "mode", "arc" is displayed. In this step 7, since cutting is selected as the processing type, the line L42 connecting the point 6 taught in step 7 and the point 5 taught in step 6 immediately before step 7 is regarded as a cutting line. The cutting line L42 corresponds to the previous step S13
Since the arc is input using the two-dimensional CAD, the "arc" indicating that the cutting line L42 is an arc is displayed in the lower column of the "mode" on the screen S as described above. .

Next, the groove angle is 30.0 degrees and the cutting width is 0.0 m.
m and the root face 5.0 mm. Further, as in the teaching of the corner processing described above, a set of the control data such as the moving speed of the torch 11 corresponding to the number “6” is designated. Therefore, “6” is displayed in the lower column of “condition”.

<Teaching of Cutting along Third Cutting Line> Next, in step 8, which is the eighth teaching stage, a cutting operation along the third cutting line L43 is taught. Step 8
The display in the lower column of the screen S at the end of the input in step S is as shown in the row of step 8 in FIG.

First, as shown in FIG.
The point 7 is taught at the position of the cutting end point. Next, cutting is selected as the type of processing. As a result, “Disconnect” is displayed in the lower column of “Process” on the screen S, and at the same time,
In the lower column of "mode", "line segment" is displayed. In this step 8, since cutting is selected as the type of processing, the line L43 connecting the point 7 taught in step 8 and the point 6 taught in step 7 immediately before step 8 is regarded as a cutting line. The cutting line L43 corresponds to the previous step S13
Since the line is input as a straight line using the two-dimensional CAD, a "line segment" indicating that the cutting line L43 is a straight line is displayed in the lower column of the "mode" on the screen S as described above. I do.

Next, the groove angle was 30.0 degrees and the cutting width was 0.0 m.
m and the root face 5.0 mm. Further, as in the teaching of the corner processing described above, a set of the control data such as the moving speed of the torch 11 corresponding to the number “6” is designated. Therefore, “6” is displayed in the lower column of “condition”.

Since the cutting line L42 and the cutting line L43 are smoothly connected at the connection point 6, the corner processing at the point 6 is not required. Therefore, the cutting line L
Following the cutting along the cutting line 42, it is taught that the cutting along the cutting line L43 is continued.

<Teaching of escape operation> Finally, at step 9 which is the ninth teaching stage, the escape operation is taught. The display in the lower column of the screen S at the time when the input in step 9 is completed is as shown in the row of step 9 in FIG.
The escape operation pattern data is selected as the pattern data. For example, the second pattern data is selected from various registered escape operation pattern data.
As a result, "Escape 2" is displayed in the lower column of "Process" on the screen S. Here, it is assumed that the selected pattern data of the second escape operation is the above-described pattern data shown in FIG.

In step 9, point 8 is taught as shown in FIG. Points 7 and 8 correspond to reference points B41 and B42 in FIG. 9, respectively. Point 7 which is the younger step number, that is, the point taught in step 8
Is associated with the reference point B41. That is, the coordinate values of the points 7 and 8 are substituted as the coordinate values of the reference points B41 and B42, respectively. The reference point B42 is a point that determines the direction away from the final cutting line. It is desirable that the torch 11 be separated smoothly from the cutting line, and therefore, the reference point B4
It is preferable to determine the position of the reference point B42 so that No. 2 is located. Therefore, the point 8 should be taught on the extension of L43 which is the cutting line to be finally cut in FIG. Since the escape operation pattern data is selected as the pattern data, "reference point" indicating that point 8 is automatically regarded as the reference point is displayed in the lower column of "mode".

Since the escape operation pattern data is selected as the pattern data, conditions such as a groove angle, a cutting width, a root face, and a moving speed of the torch 11 are also input. In order to improve the finish of the cut surface at the cutting end point, it is preferable that these input data be the same as the input data in the cutting process. Therefore, enter 30.0 degrees, a cutting width of 0.0 mm, and a root face of 5.0 mm as the groove angle. Also, as in the above teaching of cutting, a set of the control data such as the moving speed of the torch 11 corresponding to the number “6” is designated. Therefore, “6” is displayed in the lower column of “condition”.

[Operation Based on Teaching Data of FIG. 14] FIG.
FIGS. 5 and 16 are operation explanatory diagrams schematically showing how the torch 11 operates based on the above-described teaching data shown in FIG. The teaching data shown in FIG. 14 created in step S14 is converted into NC format teaching data in step S15. At this time, the pattern data of the pre-processing and the pattern data of the post-processing described above are added to the teaching data from the sensing to the escape operation shown in FIG. 14 and converted into the teaching data in the NC format. In a case where the teaching data is not directly converted into the teaching data in the NC format in step 15 but directly proceeds from step S14 to step S16 and is converted into teaching data in the robot coordinate system, in step 16, the preprocessing is performed. And the post-processing pattern data are added to the teaching data from sensing to the escape operation shown in FIG. 14 and converted into teaching data in the robot coordinate system.

In FIGS. 15 and 16, the numbers in parentheses are point numbers. That is, (1) to (8) are point numbers of points corresponding to points 1 to 8 in FIG. Numerical values without parentheses indicate distances in millimeters (mm). Symbols P1 to P52,
And the symbols B11 to B42 correspond to the position of the torch 11 and the reference point represented by the same symbols in FIGS. Coordinate axes X, Y, Z are coordinate axes in the NC coordinate system, and coordinate axes x, y,
It is assumed that z has been set to be parallel to each of these. A work W having a shape shown in FIG. 13 and having a thickness of 10 mm is mounted and fixed at a predetermined position on a work mount WF, and then a cutting robot RB based on the teaching data.
Start operation.

<Preprocessing> When the operation of the cutting robot RB is started, first, the torch 11 performs preprocessing. That is, the torch 11 moves from the standby position P1, which is the initial position, to the point P3 via the point P2, ignites a pilot flame, and returns to the point P1 again via the point P2. Then, it moves to point P4 (or point P11) which is the start point of sensing.

<Sensing> Next, the torch 11 performs sensing. First, the torch 11 changes its direction at the position of the point P11 so as to form an angle of 45 degrees with the Z axis. Subsequently, the torch 11 starts moving from the point P11, and performs sensing while moving to the point P13 after passing through the point P12. When the detector 25 detects that the tip of the probe 22 attached to the torch 11 has come into contact with the surface of the work W, the position, particularly the Z coordinate value, is stored, and the direction of the movement of the torch 11 is changed. , Back to the point P12. Then, it moves toward the point P14, and the point P14,
After passing through the points P15 in order, the flow goes to the point P13, and sensing is performed again therein. The position of the torch 11 when the tip of the probe 22 comes into contact with the surface of the work W, in particular, the Y coordinate value is stored. After the sensing, the torch 11 changes its moving direction and returns to the point P15. Subsequently, the torch 11 is at the point P
After passing through point P16, which is the starting point of the approach operation
(Or move to point P21).

The Z coordinate value and the Y coordinate value stored in the above sensing are compared with the original Z coordinate value and the Y coordinate value of the corresponding position of the work W. Correction is made by subtracting these deviations from the Z coordinate value and the Y coordinate value of the torch 11 in the teaching data relating to the operation. However, the pattern data in which the position of the torch 11 is given in the NC coordinate system from the beginning, that is, the coordinate values related to the post-processing pattern data are not corrected. Therefore, for example, the coordinate values of points P16 to P51 and points 3 to 8 are corrected, but the coordinate values of point P52 are not corrected.

In order to detect and correct the deviation in the X direction of the mounting position of the work W in the X direction and the deviation of the mounting position including the direction of the work W, it is necessary to further perform sensing on a large number of locations on the work W. In this example, for the sake of simplicity, only the deviation in the Z direction and the Y direction of the mounting position of the workpiece W is corrected as described above. FIGS. 15 and 16 show the case where there are no deviations in order to avoid complicating the drawing. Therefore, the corresponding coordinate axes (for example, the z axis and the Z axis) of the workpiece coordinate system and the NC coordinate system are parallel to each other.

<Approach Operation> Point P16 (or point P2
The torch 11 that has reached 1) subsequently starts an approach operation. Point 3 (reference point B21) is the first cutting line L41
At a distance of 20 mm from point 4 (reference point B22). The point P22 is located at a distance of 20 mm from the point 3 on the extension line, and the point P22 is located at a position further 20 mm away from the point P21 on the extension line at a distance of 30 mm in the positive direction of the z-axis.

The torch 11 has points P21, P21, 3
A trajectory obtained by translating each line segment connecting (reference point B21) and point 4 (reference point B22) with a predetermined direction and distance based on a specified value of a groove angle, a cutting width, and a root face is traced. And moves while maintaining a predetermined direction determined by the groove angle. First, the torch 11 moves the point 21 from the point 21 to the point Q21 which has been translated in the above-described manner, and further changes its direction to the predetermined direction. After that, it moves along the above-mentioned trajectory while maintaining its orientation, and reaches the point Q22 where the point 4 is translated in the above-described manner.

The torch 11 temporarily stops at the point Q22, and preheats the work W with a pilot flame. When the preheating is completed, the torch 11 starts jetting an oxygen flame. The trajectory of the torch 11 and the predetermined direction will be described in the description of the next cutting.

<Cutting> The torch 11 starts cutting the work W from the point Q22. Groove angle 30.0 degrees, cutting width 0.0mm
Since the root face is specified to be 5.0 mm, the cutting along the first cutting line L41 is a line on the main surface of the work W separated from the cutting line L41 by a distance of 2.89 mm based on Equation 1. The processing is executed according to M41. Point Q22 is line M41
Is located at one end of. The center axis Ax of the torch 11 is always perpendicular to the line M41, and forms an angle of 30 °, which is a groove angle with the z-axis, to perform the upward groove cutting.

The torch 11 in the above approach operation
Is determined in the same manner as the trajectory and direction of the torch 11 in cutting. That is, in the approach operation, the groove angle, the cutting width, and the root face are designated to the same values as in the cutting, and accordingly, the target positions of the torch 11 are set to the points P21, P22, and P3. Each line segment connecting (reference point B21) and point 4 (reference point B22)
The robot moves along a trajectory obtained by performing parallel translation at a distance of 2.89 mm given by Equation 1 in a direction perpendicular to each of these line segments and the z-axis. The central axis Ax of the torch 11 is always perpendicular to the trajectory and forms an angle of 30 degrees with the z axis, which is a groove angle.

Therefore, the torch 11 smoothly moves from the approach operation to the cutting along the first cutting line while keeping the same posture and along a predetermined trajectory. For this reason, at the starting point of the cutting along the first cutting line, a good finish of the cut surface is realized.

After the cutting along the first cutting line, corner processing, cutting along the second cutting line, and cutting along the third cutting line follow. The cutting along the second and third cutting lines is executed in the same manner as the cutting along the first cutting line. That is, the torch 11 follows the lines M42 and M43 on the main surface of the work W separated from the cutting lines L42 and L43 by a distance of 2.89 mm given by Equation 1, and the central axis Ax is the line M42. The workpiece W is always perpendicular to M43 and moves so as to form an angle of 30 degrees with the normal to the main surface of the work W. As a result, the linear cutting line L41
Not only that, but also along the cutting lines L42 and L43 having an arc shape, a groove cutting having a predetermined groove angle, a root face, and the like is realized.

<Corner processing> Based on the teaching data,
At the connection point (point 5) between the cutting along the cutting line L41 and the cutting along the cutting line L42, a corner process is performed.
FIG. 16 shows an enlarged operation of the torch 11 in the corner processing. In FIG. 16, a line segment L51 is on the extension of the line segment L41 which is a cutting line, and is a line segment having a length of 20 mm and having one end at a point 5 which is an end point of the line segment L41. The line segment L52 is also on the extension line, and has a length adjacent to the line segment L51.
2.89mm line segment. The length 2.89 mm is the distance given by Equation 1. Since the groove angle, cutting width, and root face in the corner processing are specified to be the same values as in the cutting, the distance given by Equation 1 is the cutting. Has the same value as the above distance. Line segment L53 is line segment L51 and line segment L
A line segment having a length of 2.89 mm and having the connection point P61 of 52 as one end intersects the line segment L51 at right angles. The line segment L57 is a line segment having a point 5 having a length of 20 mm on the tangent line at the point 5 of the arc L42, which is a cutting line, as one end. The line segment L56 is also on the tangent line and is a line segment having a length of 2.89 mm adjacent to the line segment L57. Line segment L55 is a connection point P between line segment L56 and line segment L57.
A line segment having a length of 2.89 mm and having 62 as one end, and a line segment L57
Cross at right angles. The arc L54 is an arc having a radius of 20 mm with both ends of the points P61 and P62.

The torch 11 has a target position of a line or an arc M51 to M57 on the main surface of the work W or an extension plane thereof at a distance of 2.89 mm from each of the line or the arc L51 to L57 and L42. , And move so that the central axis Ax thereof is always perpendicular to the line segment or the arcs M51 to M58 and forms a groove angle of 30 degrees with the normal to the main surface of the work W. For this reason, the torch 11 is
When it is located at a point Q61 which is a connection point of the line segment M53 and a point Q62 which is a connection point of the line segment M55 and the line segment M56, the direction of the central axis Ax is changed.

In the corner processing, the torch 1
1 operates, the cutting plane C41 formed by cutting along the first cutting line L41 and the cutting plane C42 formed by cutting along the second cutting line L42 are both
The two lines form a sharp edge at the boundary line D41 and are connected without being disturbed near the boundary line D41.

<Escape Operation> The torch 11 is the end point of the cutting along the third cutting line L43 and the point 7 (reference point B4
When the point Q41 corresponding to 1) is reached, the cutting is terminated and the operation shifts to the escape operation. Point 8 (reference point B42) is a distance of 20 mm from point 7 on the extension of the third cutting line L43. Point P41 is at a distance of 20 mm from point 8 on the extension line,
Point P42 (P51) is 30 points from point P41 on the extension line.
It is further 20 mm away from the distance of mm in the positive direction of the z-axis.

The torch 11 translates each line segment connecting the point 7, the point 8, the point P41, and the point P42 in a direction perpendicular to the line segment and the z-axis at a distance of 2.89 mm given by Expression 1. The trajectory moves along the obtained trajectory, and the central axis Ax is always perpendicular to the trajectory and maintains an angle of 30 degrees with the z-axis, which is a groove angle. The distance given by Expression 1 has the same value (2.89 mm) as the distance in cutting since the groove angle, cutting width, and root face in the relief operation are designated to the same values as in cutting. The oxygen flame spouted by the torch 11 is extinguished at the point P41, and the seed flame is maintained thereafter.

Since the escape operation is performed as described above, the torch 11 smoothly moves along the predetermined trajectory from the cutting along the third cutting line to the escape operation while maintaining the same posture. . Therefore, at the end point of the cutting along the third cutting line, a good finish of the cut surface is realized.

<Post-Processing> When the torch 11 reaches the final point Q42 of the escape process, the torch 11 executes the post-process. The torch 11 changes its orientation to Z at point Q42.
It changes in the direction along the axis, and moves to the point P51. When the torch 11 reaches the point P51, the torch 11 is at the standby position P52 (P
Move to 1) and stop, and end all the operations based on the teaching data.

[Effects of this embodiment] As described above, in the cutting robot RB of this embodiment, the pattern data is obtained for each operation stage of pre-processing, sensing, approach operation, corner processing, escape operation, and post-processing. Create and register in advance. These operations are shown in FIGS.
As shown in FIG. 2, one example of each operation is a complicated operation that includes the operation of the torch 11 in a three-dimensional space and also incorporates the advanced skills of a skilled person. Once these pattern data are registered, the CR
Only by selecting the menu on the screen of T16, it is possible to easily teach the operation of the cutting robot RB that reflects the advanced skills of the skilled person.

In each of the above operation stages, it is necessary to designate the position and direction of the operation of the torch 11 for the pattern data relating to the sensing, approach operation, corner processing and escape operation. The position and direction of the torch 11 to be specified can be easily determined only by using the mouse 18 to specify a predetermined reference point in the two-dimensional shape of the work W created by the two-dimensional CAD and displayed on the screen of the CRT 16. Can be taught.

In each of the above-mentioned operation steps, the cutting conditions such as the groove angle, the root face, the cutting width and the like relating to the three-dimensional groove cutting can be obtained by simply inputting these numerical values using the keyboard 17. Easy to teach. Torch 11
Is based not only on the line but also on the arc-shaped cutting line based on the two-dimensional CAD data on the cutting line and the above conditions, while keeping the target position of the torch 11 at the optimum position also in the direction of the central axis Ax. In addition, complicated three-dimensional groove cutting can be performed.

In each of the operation steps described above, the pattern data relating to the approach operation, corner processing, and relief operation leading to the cutting, as well as the conditions for the complicated three-dimensional groove cutting, are the same as in the teaching of the cutting operation. Can be easily taught. As a result, these operations are smoothly connected to the cutting operation, and a good cut surface can be formed.

[Other Embodiments] The present invention, in which pattern data including a complicated three-dimensional operation of an end effector is created and registered in advance, and teaching is performed by selecting from the registered pattern data, is described above. Not only the cutting robot shown in the embodiment but also a general processing robot such as a welding robot can be used.

[0120]

[0121]

According to the first aspect of the present invention, there is provided an offline teaching method for a machining robot, wherein a planar image of a workpiece is displayed on an image display means, teaching is performed based on the planar image, and the workpiece is prepared and registered in advance. In addition, teaching is performed by designating a three-dimensional operation of the end effector which requires designation of a position, and further designating a reference point on a planar image to designate the position. For this reason, the teaching of a complicated three-dimensional operation including the posture of the end effector, which also incorporates the advanced skills of a skilled person, is performed by an operation equivalent to the conventional technology of teaching the two-dimensional operation of the end effector based on a planar image. There is an effect that can be executed with ease and efficiency.

In the off-line teaching method for a machining robot according to the second and third aspects of the present invention, a plane image of the workpiece is displayed on the image display means, teaching is performed based on the plane image, and the cutting line is displayed on the plane image. specified, included angle associated with the cutting line, by entering the cutting conditions such as the root face, complex 3 including the attitude of the end effector
Teaches dimensional motion. For this reason, the teaching of complicated three-dimensional groove cutting is performed by the end effector 2 based on the planar image.
Ease of operation equivalent to conventional technology teaching dimensional motion,
There is an effect that can be executed efficiently.

In the off-line teaching method for a machining robot according to a third aspect of the present invention, the target position of the end effector in the direction of the center axis is most determined when cutting based on the taught cutting line and cutting conditions. Achieve cutting at a suitable position on the surface of the workpiece. For this reason, the teaching of the optimal target position in the center axis direction of the end effector can be performed with the same ease and efficiency as the conventional technique of teaching the two-dimensional operation of the end effector based on the planar image. There is an effect that can be done.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a schematic procedure of a teaching operation according to an embodiment of the present invention.

FIG. 2 is a schematic perspective view showing a configuration of a cutting robot system according to one embodiment of the present invention.

FIG. 3 is a flowchart showing a schematic procedure of an operation of the cutting robot according to one embodiment of the present invention.

FIG. 4 is a schematic diagram showing a schematic configuration of an apparatus for performing sensing according to an embodiment of the present invention.

FIG. 5 is an operation explanatory diagram for explaining the contents of an example of preprocess pattern data according to an embodiment of the present invention;

FIG. 6 is a diagram illustrating an example of sensing pattern data according to an embodiment of the present invention;

FIG. 7 is an operation explanatory diagram illustrating an example of pattern data of an approach operation according to an embodiment of the present invention;

FIG. 8 is an operation explanatory diagram illustrating an example of the contents of pattern data of corner processing according to an embodiment of the present invention;

FIG. 9 is an operation explanatory diagram illustrating an example of the content of pattern data of an escape operation according to an embodiment of the present invention;

FIG. 10 is an operation explanatory diagram for explaining the contents of an example of post-processing pattern data according to an embodiment of the present invention;

FIG. 11 is an operation explanatory diagram for explaining an operation of the torch at the time of upper groove cutting according to an embodiment of the present invention;

FIG. 12 is an operation explanatory diagram for explaining an operation of the torch at the time of lower groove cutting according to an embodiment of the present invention;

FIG. 13 is an image displayed on a CRT screen at the final stage of teaching according to an embodiment of the present invention.

FIG. 14 shows C at each teaching stage according to an embodiment of the present invention.
It is a list of a set of teaching data displayed in the lower column of RT.

FIG. 15 is an operation explanatory view schematically showing how the torch operates based on the teaching data shown in FIG. 14 according to one embodiment of the present invention.

FIG. 16 is an enlarged operation explanatory view schematically and enlargedly showing a state in which the torch executes a corner process based on the teaching data shown in FIG. 14 according to one embodiment of the present invention;

[Explanation of symbols]

 11 Torch 14 Robot control panel 15 Personal computer 16 CRT RB Cutting robot W Work Ax Center axis of torch S CRT screen B11-B42 Reference point

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G05B 19/42 G05B 19/4093

Claims (3)

(57) [Claims] An operation of a machining robot is taught by displaying a planar image of an object to be machined on an image display means.
In the offline teaching method for a machining robot, (a) a step of collectively registering, in a predetermined stage of machining, an operation of the end effector of the machining robot in a three-dimensional space as pattern data in advance; and (b) two-dimensional CAD. A step of displaying, on the image display means, a planar image of the input object including a shape to be processed; (c) a step of specifying the pattern data registered in the step (a); (D) a step of specifying a reference point of the pattern data together with its position on the plane image; and (e) a step of specifying the contents specified in the pattern data specified in the step (c) in the step (d). further defines the contents, and a step of creating teaching data operation on the three-dimensional space including a posture of the end effector in at the position of the reference point specified Off-line teaching method of engineering robot. 2. The operation of a machining robot is taught by displaying a planar image of an object to be machined on an image display means.
In the offline teaching method for a processing robot, the processing robot is a cutting processing robot, and (a) a planar image including a shape to be cut of the processing target input by two-dimensional CAD is displayed by the image display means. (B) specifying a cutting line along the shape to be cut on the plane image; and (c) a groove angle, a root face, and a cut in the cutting along the cutting line. And specifying a cutting condition having a cutting width, and (d) including a posture of an end effector of the processing robot.
Teaching data activity on the non-three-dimensional space, wherein step (b)
A step of creating based on the cutting line specified in step (c) and the cutting conditions specified in step (c). 3. The step (d) includes: (d-1) generating the teaching data so that a target position of the end effector in a center axis direction of the end effector is positioned on a surface of the workpiece. The offline teaching method for a machining robot according to claim 2 , comprising the steps of: