JP3330386B2 - Automatic teaching method of industrial robot and industrial robot device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a teaching / playback type industrial robot, and more particularly to an industrial robot used for operations such as arc welding, spot welding, painting, deburring, sealing, and thermal spraying. Teaching method
And equipment .

[0002]

2. Description of the Related Art Teaching / playback type robots are mainly used as industrial robots.
Therefore, the efficiency of teaching (teaching) work for it has been one of the major propositions that need to be solved conventionally.

[0003] For this reason, for the teaching method of the robot, various techniques have been conventionally proposed. For example, in Japanese Patent Application Laid-Open No. 61-175805,
A method for facilitating robot teaching by using motion trajectory sequence data obtained from a three-dimensional position measuring device as position and orientation data for arm movement in a robot control program is disclosed. 62
Japanese Unexamined Patent Publication No. 274308 discloses a method of teaching the posture and position of a tool by displaying the relationship between a work model and a work tool on a CRT screen. Therefore, danger in the robot teaching operation can be reduced.

[0004]

The above-mentioned prior art only discloses that teaching can be performed off-line, but does not consider automation of teaching, and has the following problems. . First, in the prior art, regardless of online teaching / offline teaching, when the work to be worked is different, the difference is that even if there is only a slight difference, such as only a part of the size of the work is different. , For new workpieces,
All of them had to be taught again one point at a time.

More specifically, as shown in FIGS. 11 and 12, a work A for welding a strip member A2 to a tubular member A1 and a work B for welding a strip member B2 to a tubular member B1 are also provided. These are the lengths of the tubular members A1 and B1, the lengths of the strip members A2 and B2, the mounting position of the strip member A2 on these tubular members A1, and the strips on the tubular member B1. It is assumed that only the attachment position of the shape member B2 is different, and among them, as for the work A, as shown in FIG. 11, the operation path of the robot has already been taught, and the teaching data exists. Even in this case, in order to obtain the teaching data of the work B, conventionally, as shown in FIG. If It was bought. In FIGS. 11 and 12, P100, P20, P30, and P4
To P15 each represent a teaching point.

[0006] In addition, the teaching work requires various knowledges,
It is not possible to obtain accurate teaching simply by specifying the position. For example, in arc welding, knowledge of the torch attitude during welding, welding speed, etc. is required,
In the teaching work, a person with such knowledge must teach. Therefore, the conventional technique has a problem that the teaching operation always requires a high degree of skill and a great amount of time.

An object of the present invention is to provide only a slight difference, such as when a work having teaching data (hereinafter referred to as a reference work) is partially different from the work. For another new work (hereinafter referred to as the actual target work or the target work), knowledge of the teaching work is not required, and accurate teaching data is automatically obtained only by teaching simple positions of a part of the work. Automatic teaching method and industrial robot for industrial robot
It is to provide a device .

[0008]

An object of the present invention is to provide a manipulator having at least two degrees of freedom, which is provided on a reference work.
The teaching data taken from a plurality of specified auxiliary points
Find coordinate points of reference data and represent them in robot coordinate system
Robot operation path teaching data of the reference work being performed
Is the motion path represented by the coordinate system of this reference work.
After converting it to teaching data, it is
Dimension data of workpieces and deviations of component mounting positions
Using the correction data obtained from
After converting to road teaching data, it is
By conversion to that motion path teaching data, the automatic teaching method for an industrial robot which is controlled by the teaching playback system and to obtain a motion path teaching data for purposes workpiece, executes the robot at each taught point
This welding operation to be, tack welding, sensing operations, in accordance with at least one working air cut work,
The teaching point becomes the motion path teaching point that matches the target work
The working conditions taught before and after each teaching point.
Training according to the procedure set in advance for each of the tasks
Automatic teaching operation that automatically analyzes the data in order from the beginning
Line processing, and the automatic teaching
This is achieved by creating motion path teaching data for a target work . In addition, the above object is to provide a manipulator having at least two degrees of freedom, and to set a plurality of
The reference data is obtained from the teaching data
Of the robot coordinate system and expressed in the robot coordinate system.
The robot movement path teaching data of the reference work
Motion path teaching data expressed by the coordinate system of the quasi-work
After converting it to parts of the reference work and the target work
Obtained from the dimensional data and the deviation of the component mounting position
Path data for the target workpiece using the correction data
After converting the data to a robot path,
In an industrial robot apparatus controlled by a teaching / playback method in which operation path teaching data for a target work is obtained by converting the data into teaching data ,
Main welding work, tack welding work, sensing work, air cut work to be performed by the robot at each teaching point
In accordance with at least one type of work, the teaching point is
Of each teaching point so that the motion path teaching point matches the
Based on the working conditions taught before and after,
From the beginning of the teaching data according to the procedure set for each
Automatic teaching execution processing means for automatically analyzing in order is provided,
By this automatic teaching execution processing means, the
This is also achieved by a configuration in which the motion path teaching data is created .

[0009]

[0010]

[0011]

When the above-described relationship between the reference work and the target work is established, the above-described configuration is used to input the above-described component dimension data and the component mounting position data of the reference work and the target work. The teaching of the robot motion path to the target work can be automatically given only by obtaining the teaching data from the set predetermined number of auxiliary points. Therefore, the robot motion path to the target work is point-by-point teaching. There is no need to perform the teaching operation, and no knowledge of the teaching operation is required, and anyone can easily teach.

Further, by the above-mentioned solution means, during the automatic teaching, the work to be performed by the robot at each teaching point is automatically analyzed based on the working conditions before and after the teaching point, and the robot is moved to the movement path of the target work. Since the conversion method is automatically determined, any teaching data can be automatically taught.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An automatic teaching method and an industrial robot apparatus for an industrial robot according to the present invention will be described below in detail with reference to the illustrated embodiments. FIG. 2 is an overall configuration diagram showing an example of a robot device to which the present invention is applied. In this example, a case where the present invention is applied to a welding robot is shown.
In FIG. 1A, reference numeral 1 denotes a main body of a personal computer. A CRT screen 2 displays various processing menus and execution states. Reference numeral 3 denotes a floppy disk driver (hereinafter, referred to as FDD). The reference teaching data and the auxiliary point data stored in the floppy disk (hereinafter, referred to as FD), which are taught by a robot to a reference work, are taken in from here. The function of storing the teaching data automatically created by this device in the FD is provided.

Next, 4 is a keyboard and 5 is a mouse. Input of data necessary for automatic teaching, selection of a process, and execution are performed by the keyboard 4 and the mouse 5. Reference numeral 6 denotes a printer for printing an execution result of the automatic teaching. Although this embodiment is described using a personal computer, the present invention can be similarly implemented using a workstation, a large-scale computer, a robot control device, or the like.

In FIG. 2B, reference numeral 7 denotes a robot body (manipulator) which is driven by six actuators. 8 is a robot control unit. Reference numeral 9 denotes a playback console for starting and stopping during automatic operation. Reference numeral 10 denotes a programming unit for performing a teaching operation, an operation speed, and a real-time change of a weaving frequency of the robot. Reference numeral 11 denotes a welding machine, which includes a welding power supply unit and an interface unit. 12
Is a welding wire, which is driven by the wire supply device 13. Reference numeral 14 denotes a torch as a working tool. Reference numeral 15 denotes an FDD for a robot, which is used to transfer teaching data.

In this embodiment, the transfer of the teaching data is performed by the FD, but the transfer may be performed by communication. Further, as described above, in this embodiment, a case where the present invention is applied to a welding robot is described, but the same applies to a robot for deburring, sealing, assembling, painting, and the like.

FIG. 3 is a block diagram of a personal computer in this embodiment. The CPU 21 controls various controls of the personal computer (memory management, task management, etc.).
The calculation of the automatic teaching execution process is also performed here. The memory 22 is an area for loading a processing procedure performed by the CPU 21 and an area for storing data being executed. The hard disk 23 has a function of storing various files, and stores therein a program describing an automatic teaching execution processing procedure, operation path teaching data of a robot, and dimension data of a work component. The ROM 24 stores a program describing initial processing to be performed when the power of the personal computer is turned on. The numerical calculator 25 performs a process regarding a decimal point calculation in a program describing a processing procedure. FDDi
/ F26 is FDD27, keyboard i / f28 is keyboard 29, and CRTi / f30 is CRT31.
And an interface for exchanging data.

Next, a software data flow in this embodiment will be described with reference to FIG. First, the reference work motion path teaching data 41 created by the robot
And the reference work auxiliary point teaching data 42 are supplied by the FD. It is fetched by the reference work teaching data fetching process 43 and stored in the hard disk 23 (reference work operation path teaching data 44, reference work auxiliary point teaching data 45). Here, examples of the reference work motion path teaching data 41 and the reference work auxiliary point teaching data 42 are shown in FIGS.
Respectively. Next, under the control of the reference workpiece component dimension input processing 47 and the target workpiece component dimension input processing 50, the operators 46 and 49 input the component dimensions of the reference workpiece and the target workpiece, respectively. Table 1 shows the input items.

[0019]

[Table 1]

That is, a dimension input screen is displayed on the CRT 31, and component dimensions are inputted by the operators 46 and 49, and the reference work part dimension data 48 and the target work part dimension data 51 are stored in the hard disk 23. Next, each data 44, 4 created in this way
An automatic teaching execution process 52 is performed based on 5, 48, and 51 to create target work operation route teaching data 53. The automatic teaching execution processing 52 will be described later.

Finally, data 53 created by the automatic teaching execution process 52 and stored in the hard disk 23
Is output to the FD by the target work teaching data output processing 54 to create target work operation path teaching data 55.
Therefore, the target work motion path teaching data 5 is obtained from the FD created in this way by the robot FDD 15.
By reading 5, for example, automatic teaching using the work A in FIG. 11 as a reference work and the work B in FIG. 12 as a target work can be obtained. Here, each of the processes 43, 47, 50, 52, and 54 is activated by being designated by the operator each time by a menu selection method.

Next, the contents of the processing by the automatic teaching execution processing 52 will be described with reference to the flowchart of FIG. First, in a process 61, a robot coordinate system / work coordinate system conversion matrix R is obtained and set. here,
The matrix R is expressed as (Equation 1), and the a vector is obtained by (Equation 2) using the auxiliary points P1 and P2 in FIG.

[0023]

(Equation 1)

[0024]

(Equation 2)

The vector o is, as shown in (Equation 3), a unit vector of a vector obtained by subtracting the projection vector s of the vector w from the auxiliary points P1 to P3 in FIG. Become.

[0026]

(Equation 3)

Further, the vector n is obtained by the cross product of the vector a and the vector o as shown in (Equation 4).

[0028]

(Equation 4)

The inverse matrix invR of the matrix R is given by (Equation 5)
It becomes as shown in.

[0030]

(Equation 5)

Next, in step 62, the reference work operation path teaching data is extracted, and the contents of the data are converted into the processing corresponding to each of the point conversion processing 66 to 69 by the determination processing of 63 to 65. Sorting,
Execute one of them. Here, reference numeral 66 denotes a point conversion process for performing actual welding, 67 denotes a point conversion process for performing tack welding, 68 denotes a point conversion process for performing sensing, and 69 denotes an air cut point conversion process.

Next, after performing the point processing of each instruction,
It is determined whether or not all the teaching data has been converted by the process 70.
If not, the process returns to step 62, and the process is repeated. In process 71, the target work motion path teaching data 5
5 is stored in the hard disk 23 and the process is terminated.

Next, the main welding point conversion processing 66 will be described with reference to FIG. First, the main welding start point Ps and end point Pe are extracted from the reference work operation path teaching data. Then, this point is multiplied by the inverse matrix invR shown in (Equation 5) to obtain the point data Psb and Peb in the work coordinate system.
(Equation 6).

[0034]

(Equation 6)

Next, the point data Psb and Peb are set so that the welding quality of the reference work and the target work is the same.
Data dsx, dex, dsz, and dez indicating the positional relationship with the workpiece are obtained by (Equation 7), (Equation 8), (Equation 9), and (Equation 10), respectively.

[0036]

(Equation 7)

[0037]

(Equation 8)

[0038]

(Equation 9)

[0039]

(Equation 10)

Here, Tb: plate thickness of the reference work flat part Db: diameter of the reference work cylindrical part Lfb: length of the reference work flat part To: plate thickness of the target work flat part Do: diameter of the target work cylindrical part Lfo : Assuming that the length of the target workpiece flat part, the X and Z components of the points Pso and Peo of the target workpiece are expressed as follows.

[0041]

[Equation 11]

[0042]

(Equation 12)

[0043]

(Equation 13)

[0044]

[Equation 14]

For the Y component, first, the XY of the points Pso and Peo of the target work are calculated by (Equation 15) and (Equation 16) so that the converted point is located on the cylindrical work.
The angles Theta1 and Theta2 in the plane are obtained.

[0046]

(Equation 15)

[0047]

(Equation 16)

Then, the angles Theta1 and Theta2 are
The Y components of Pso and Peo are obtained by substituting into (Equation 17) and (Equation 18).

[0049]

[Equation 17]

[0050]

(Equation 18)

Finally, the points Pso and Peo of the target work expressed in the work coordinate system are converted into the robot coordinate system according to (Equation 19), and the process ends.

[0052]

[Equation 19]

Next, the tacking welding point conversion process 67 will be described with reference to FIG. First, the data of the tack welding start point Ps and the end point Pe are extracted from the reference work operation teaching path data. Then, this point is multiplied by the inverse matrix invR shown in (Equation 5) and converted into point data Psb and Peb in the work coordinate system (Equation 6). Next, the point data Psb and Peb and the data dsx, dex, dsz and dez indicating the positional relationship of the work are respectively expressed by (Equation 7) and (Equation 8) so that the quality of the reference work and the target work is the same. , (Equation 9) and the following (Equation 20).

[0054]

(Equation 20)

Here, as described above, Tb: thickness of the reference work flat part Db: diameter of the reference work cylindrical part Lfb: length of the reference work flat part To: plate thickness of the target work flat part Do: target work Assuming that the diameter Lfo of the cylindrical part is the length of the flat part of the target work, the X and Z components of the points Pso and Peo of the target work are represented by (Equation 11), (Equation 13), (Equation 21), and (Equation 22). It is represented as

[0056]

(Equation 21)

[0057]

(Equation 22)

As for the Y component, as in the main welding point conversion processing 66, (Equation 15), (Equation 16), and (Equation 1)
7) and (Equation 18). Finally, according to (Equation 19), the points Pso and Peo of the target work expressed in the work coordinate system are converted into the robot coordinate system, and the processing is completed.

Next, the sensing point conversion processing 68 will be described with reference to FIG. First, the sensing points P ₁ , P ₂ ,
Take out P ₃ and P ₄ . Then, these points are multiplied by the inverse matrix invR shown in (Equation 5) and converted into point data P _1b , P _2b , P _3b , P _4b in the work coordinate system (Equation 6). Subsequently, data d _2y and d _2z indicating the positional relationship between the point P _2b and the work are obtained by ( _Equation 23) and ( _Equation 24).

[0060]

(Equation 23)

[0061]

(Equation 24)

Here, as described above, Tb: thickness of the reference work flat part Db: diameter of the reference work cylindrical part Lfb: length of the reference work flat part To: plate thickness of the target work flat part Do: target work Assuming that the diameter Lfo of the cylindrical part is the length of the flat part of the target work, the point P _{2O of the} target work is expressed by (Equation 25),
It is obtained by (Equation 26) and (Equation 27).

[0063]

(Equation 25)

[0064]

(Equation 26)

[0065]

[Equation 27]

On the other hand, the points P _1O and P _3O may be converted so as to be parallel to the X axis of the work coordinate system.
Data d _1X indicating the positional relationship between the point P _1b and the workpiece
If the data d _1X is obtained by (Equation 28) and the data d _1X is substituted into (Equation 29), the X components of the points P _1O and P _3O can be obtained.

[0067]

[Equation 28]

[0068]

(Equation 29)

The Y component and the Z component of the points P _1O and P _3O are calculated as shown in ( _Equation 30) and ( _Equation 31).
Has the same value as

[0070]

[Equation 30]

[0071]

(Equation 31)

The X and Z components of the point P _4O are
As shown in (expression 32) and (Equation 33), the same value as the point P _1O.

[0073]

(Equation 32)

[0074]

[Equation 33]

Further, as for the Y component of the point P _4O , first, the angle Theta of the point P _4O of the target work on the XY plane is _obtained by ( _Equation 34) so that the converted point is located on the cylindrical work. . And this angle T
By substituting heta into (Equation 35), the Y component of the point P ₄₀ is obtained.

[0076]

(Equation 34)

[0077]

(Equation 35)

Thereafter, as the last process, the points P _1O , P _2O , P _3O , and P _4O of the target work expressed in the work coordinate system are converted into the robot coordinate system according to ( _Equation 36), and the process ends. You do it.

[0079]

[Equation 36]

Finally, the air cut point conversion processing 69 will be described with reference to FIG. First, the air cut point P is extracted from the reference work operation teaching path data. Then, to this point, (5) to be multiplied by the inverse matrix invR shown to convert the point data P _b by work coordinate system (number 37).

[0081]

(37)

Next, data dx, dy, and dz indicating the positional relationship between the point _Pb and the work are respectively _{expressed by} (Equation 38),
It is determined by (Equation 39) and (40).

[0083]

(38)

[0084]

[Equation 39]

[0085]

(Equation 40)

Here, as described above, Tb: the thickness of the reference work flat part Db: the diameter of the reference work cylindrical part Lfb: the length of the reference work flat part To: the thickness of the target work flat part Do: the target work Assuming that the diameter Lfo of the cylindrical part is the length of the flat plate part of the target work, the X component, the Y component, and the Z component of the point P _O of the target work are obtained by (Expression 41), (Expression 42), and (Expression 43). .

[0087]

[Equation 41]

[0088]

(Equation 42)

[0089]

[Equation 43]

Finally, the point P _{O of the} target work expressed in the work coordinate system is converted into the robot coordinate system according to (Equation 44), and the processing is terminated.

[0091]

[Equation 44]

Therefore, according to this embodiment, the robot teaching data for attaching various shaped parts to the cylindrical part such as the work B by welding is taught only once for the reference work A. Thereafter, there is an effect that anyone can easily and automatically create the data by a simple operation.

[0093]

According to the present invention, the following effects can be obtained.

(1) Work A as shown in FIGS. 11 and 12
And the work B, it is possible to automatically teach the operation path of the robot to one of the works A, so that it is not necessary to teach the operation path of the robot to the work 2 one by one. In addition, accurate teaching can be performed even with little knowledge of teaching work.

(2) During the automatic teaching, the work to be performed by the robot at each teaching point is automatically analyzed and the method for conversion is automatically determined, so that any teaching data is automatically taught. can do.

[Brief description of the drawings]

FIG. 1 is a flowchart showing an automatic teaching execution process in an embodiment of an industrial robot automatic teaching method according to the present invention.

FIG. 2 is an overall configuration diagram illustrating an example of a robot system to which an embodiment of the present invention has been applied.

FIG. 3 is a block diagram of a personal computer main body according to an embodiment of the present invention.

FIG. 4 is an explanatory diagram of a software data flow in one embodiment of the present invention.

FIG. 5 is an explanatory diagram of an auxiliary point teaching process in one embodiment of the present invention.

FIG. 6 is a vector diagram based on auxiliary points in one embodiment of the present invention.

FIG. 7 is an explanatory diagram of a main welding point conversion process in one embodiment of the present invention.

FIG. 8 is an explanatory diagram of tacking welding point conversion processing in one embodiment of the present invention.

FIG. 9 is an explanatory diagram of a sensing point conversion process in one embodiment of the present invention.

FIG. 10 is an explanatory diagram of an air cut conversion process in one embodiment of the present invention.

FIG. 11 is an explanatory diagram of a teaching operation performed on a workpiece A by a robot.

FIG. 12 is an explanatory diagram of a teaching operation on a work B by a robot.

[Explanation of symbols]

 63-65 Automatic interpretation of teaching data 66 Main welding point conversion processing 67 Temporary welding point conversion processing 68 Sensing point conversion processing 69 Air cut point conversion processing

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Shinichi Sarugaku 7-1-1, Higashi-Narashino, Narashino-shi, Chiba Within Hitachi Keiyo Engineering Co., Ltd. (72) Inventor Masami Otomo 7-1-1, Higashi-Narashino, Narashino-shi, Chiba No. Hitachi Keiyo Engineering Co., Ltd. (72) Inventor Minoru Fujita 7-1-1, Higashi-Narashino, Narashino-shi, Chiba Hitachi-Keiyo Engineering Co., Ltd. (72) Nobuyuki Chiba 7-1-1, Higashi-Narashino, Narashino-shi, Chiba Hitachi Keiyo Engineering Co., Ltd. (72) Inventor Tomoya Tamura 7-1-1, Higashi-Narashino, Narashino-shi, Chiba Investigator, Hitachi, Ltd. Narashino Plant Inspector Makoto Yagi (56) Reference JP-A-1-252381 (JP, A JP-A-3-251378 (JP, A) JP-A-62-298806 (JP P, A) (58) investigated the field (Int.Cl. ^7, DB name) G05B 19/18 - 19/46 B25J 3/00 - 3/04 B25J 9/10 - 9/22 B25J 13/00 - 13 / 08 B25J 19/02-19/06

Claims (2)

(57) [Claims] 1. A manipulator having at least two degrees of freedom, comprising a plurality of auxiliary points set on a reference work.
The coordinate point of the reference data is obtained from the input teaching data,
Robot of reference work represented by robot coordinate system
Set the operation path teaching data to the coordinate system of this reference work.
After converting it to the motion path teaching data expressed by
Dimension data and parts of reference work and target work
Using the correction data obtained by the displacement of the mounting position
After converting the data into motion path teaching data for the target workpiece,
Is converted to motion path teaching data in the robot coordinate system.
In the automatic teaching method of the industrial robot controlled by the teaching / playback method in which the movement path teaching data for the target work is obtained, the main welding work to be executed by the robot at each teaching point, Welding work, sensing work, air cut work
In accordance with at least one type of work, the teaching point is
Of each teaching point so that the motion path teaching point matches the
Based on the working conditions taught before and after,
From the beginning of the teaching data according to the procedure set for each
Performs automatic teaching execution of automatically analyzed in turn by the automatic teaching execution processing operation for the purpose workpiece
An automatic teaching method for an industrial robot, wherein route teaching data is created . And a manipulator having at least two degrees of freedom, wherein the manipulator is provided with a plurality of auxiliary points set on a reference work.
The coordinate point of the reference data is obtained from the input teaching data,
Robot of reference work represented by robot coordinate system
Set the operation path teaching data to the coordinate system of this reference work.
After converting it to the motion path teaching data expressed by
Dimension data and parts of reference work and target work
Using the correction data obtained by the displacement of the mounting position
After converting the data into motion path teaching data for the target workpiece,
Is converted to motion path teaching data in the robot coordinate system.
The Rukoto, the industrial robot system is controlled by the teaching playback system and to obtain a motion path teaching data for purposes workpiece, the welding operation to be executed by the robot at each taught point, tack welding operation, Sensing work, air cut work
In accordance with at least one type of work, the teaching point is
Of each teaching point so that the motion path teaching point matches the
Based on the working conditions taught before and after,
From the beginning of the teaching data according to the procedure set for each
An automatic teaching execution processing means for automatically analyzing in order is provided, and the automatic teaching execution processing means
An industrial robot apparatus configured to generate motion path teaching data .