JPH10187223A - Automatic preparation system for welding robot operation program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a welding robot operation program automatic preparation system capable of sufficiently securing teachingless enabled and highly efficient welding quality in the case of welding a work having a complicated three- dimensional shape by utilizing plural welding robots. SOLUTION: A work model is generated from the work shape information of CAD data, a welding model for a basic welding line consisting of the fitting line of a fitting member 110 is generated and a cell model is generated by dividing a work 100 by area division lines 311 to 314 for determining the operation ranges of welding robots. The existence of interference between a work and a welding robot is checked in each basic welding line, and when interference is generated, a welding line shortened to a range having no interference generation is generated, the welding direction, order and route of the welding line are determined in each area and then welding design information is specified to prepare an operation program.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the application of welding robots in heavy industries such as shipbuilding and bridges, and more particularly to the application of a plurality of welding robots to large-sized, small-volume production and large-sized complicated-shaped workpieces. In some cases,
The present invention relates to a system for automatically generating an operation program of a welding robot using a CAD / CAM system.

[0002]

2. Description of the Related Art Conventionally, a welding robot in heavy industries such as shipbuilding, bridges and steel frames has been applied in a simple form in which one welding robot is applied to one work. In such an application form, work efficiency has been improved by eliminating teaching using a welding robot at a site using an off-line teaching method using a personal computer. However, in an application mode in which a plurality of welding robots are applied to one work, teaching is necessary even in an offline mode, so that it takes too much time to teach on a personal computer. It was difficult to apply to the production. To solve this problem,
The technology disclosed in Japanese Patent Application Laid-Open No. 6-214625 according to the prior application of the present applicant has been used. This is to automatically generate operation programs for a plurality of welding robots collectively using only the work shape information and the welding design information of the CAD system, thereby enabling teaching-less. However, in this system, the operation program of the welding robot is automatically determined by a relatively simple algorithm.

[0003]

In the case where the target work is of a wide variety and small quantity and has a complicated shape including many narrow portions due to a three-dimensional mounting member, welding is performed by a simple algorithm. The welding robot operation program including the path cannot be automatically determined. In particular, the determination of the welding direction and the welding sequence in consideration of the welding quality and work efficiency largely depends on the experience of the robot operator, so that the automatic determination of the welding path by the computer was a difficult task. Further, in an application in which a plurality of welding robots simultaneously perform one or more work of welding one or more workpieces, any one of the welding robots stops for control in order to avoid interference between the welding robots. As a result, a large amount of dead time is generated. Determining the welding direction and welding order to avoid such interference between welding robots has been a major issue.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and is capable of teaching-less when welding a work having a complicated three-dimensional shape using a plurality of welding robots. Another object of the present invention is to provide a system for automatically generating a welding robot operation program that is efficient and can sufficiently secure welding quality.

[0005]

An automatic generation system for a welding robot operation program according to the present invention is registered in a CAD / CAM system when a workpiece having a plurality of mounting members is welded by a plurality of welding robots. A system for reading data and automatically generating an operation program for each of the welding robots, a means for generating a work model corresponding to the work from the work shape data of the read data, and an attachment line for a component of the work. Means for generating a welding model having a basic welding line consisting of: means for generating a cell model by dividing the work model by a region dividing line so as to equalize the workload of the plurality of welding robots; Check if the workpiece and the welding robot interfere with each other for each basic welding line Means for generating a welding line in a range where interference does not occur, and for each region divided by the region dividing line, a welding direction, a welding order, and a welding order for all welding lines after the interference check included in the region. Means for determining a welding path, and, for the determined welding line, by selecting an operation sequence group called an operation pattern previously obtained from the data, allocating data necessary for welding to a series of operations. Means for generating a program.

Here, the data registered in the CAD / CAM system is mainly CAD data. As shown in Table 1, the CAD data includes work management information, work shape information, and welding lines. Information and welding design information are classified into four types. By reading these information, a work model and a welding model are generated.

[0007]

[Table 1]

[0008] The work management information and the work shape information are data necessary for generating a work model corresponding to the work, and data such as geometric data and material are registered for each component. In addition, the welding line information and welding design information are data required when generating a welding model. Among them, data on the cross-sectional shape of the mounting member, that is, scantling data, checks for interference with the welding torch and robot arm. It is the basic data when doing.

The work model generating means generates a work shape based on the work management information and the work shape information.
For example, in the case of an outer panel for shipbuilding, a work model is generated for the outer shape of the panel of the base material and the arrangement of various mounting members such as a longge and a transformer mounted on the panel.

[0010] The welding model generating means generates a basic welding line which is a basis for attaching the constituent members of the work. In the case of an attachment member, two attachment lines are generated in principle, taking into account the thickness. Generate a welding model consisting of a three-dimensional basic welding line.

[0011] The cell model generating means divides the work by an area dividing line which defines the operation range of the plurality of welding robots,
Generate a cell model for each divided area. When dividing the area, the work amount of the welding robot is set to be equalized. Further, the basic welding line may be divided by the region dividing line.

The interference checking means checks whether or not the mounting member interferes with the welding robot for each basic welding line. At the time of this interference check, the basic robot posture is fixed to a plurality of types, and based on the basic robot posture, an interference check is performed on the interference candidate member extracted from the mounting member and its surrounding members, and interference occurs. The torch angles α and β are determined within an allowable range. Here, the basic robot posture is a welding posture in a torch angle range necessary for ensuring welding quality without causing interference with the mounting member. Therefore, the posture of the robot changes depending on whether the depth of the mounting member is small or deep. The reason why the basic robot posture is fixed to a plurality of types is that when welding a complex three-dimensional workpiece by suspending multiple articulated welding robots with three external axes that are orthogonal to each other, several degrees are required. This is because it is easier to determine the crab welding posture (robot posture) and perform the interference check. Thus, by using the predetermined basic robot posture and the scuntling data of the attachment member, that is, the scantling change point and the MAX scantling data, it is possible to easily perform the interference check by the automatic processing. .

The members to be checked for interference are:
The attachment member (own member) and the proximity members located on the back side and the side surface side thereof. Among the proximity members, a member that overlaps the extraction area set for the own member is selected as the interference candidate member. Therefore, interference is checked for the own member and the members extracted as the interference candidate members among the back surface member and the side surface member, respectively, using the scantling data. Then, as a result of the interference check, when interference occurs, a welding stop point is generated on the welding line.

For each area divided by the area dividing line by the cell model generating means, a welding direction, a welding order, and a welding path are determined for all the welding lines included in the area. When the welding line satisfies a certain condition, it is selected as a twin welding line. All others are single welding lines.

The present invention is based on well-known techniques such as high-speed rotary arc welding, end position detection of an attachment member by an arc sensor, automatic welding line profiling control, and bead joining. In the means, predetermined rules are set so that these techniques can be utilized. As this rule, for example, the end of the welding line is determined so that the end position can be detected by the arc sensor. Also, when the welding line is divided by the region dividing line or when the welding line is divided by another mounting member connected to the mounting member, the bead joint is also formed on such a divided welding line. For possible welding lines, the welding direction is set to be the same, and the welding quality of the bead joint is ensured. Further, in principle, a direction toward the counterclockwise direction with respect to the mounting member is determined as a welding direction.

In the welding order determining means, for example, a rule is set so that, for a mounting member having a groove or an inclination (falling), a side having a groove or a wide angle side of the mounting angle is welded first. Have been. In principle, the welding sequence is such that the welding start point first determines the surface including the welding line closest to the robot system coordinate origin in the mounting member, and then the welding start point of the welding line group within the determined surface is determined. The welding line closest to the robot system coordinate origin is ranked first. These basic rules of the welding direction and the welding order are designed to minimize the occurrence of interference between welding robots.

The welding route determining means determines the welding routes of all the mounting members according to a predetermined algorithm based on the welding direction and the welding order determined as described above. The welding path determining means includes an interlock area setting means for setting an interlock area for avoiding mutual interference of welding robots, and a welding line selecting means for selecting a welding line included in the set interlock area. Configuration.
Further, as a predetermined algorithm, the interlock area setting means may set the operation area of the plurality of welding robots such that when the operation area of the plurality of welding robots is divided into three in the vertical or horizontal direction, the number of welding lines at least partially included in the area on the right or upper side thereof. And the area on the right or upper side of the selected division direction is set as an interlock area. When the welding line selection means divides the operation area of the welding robot into three in the selected division direction, A welding line group extending over three regions (LCR welding line group), a welding line group included in one or both of the two regions (LC welding line group or CR welding line group)
Welding line group) and select LC
The welding path is determined in the order of the R welding line group, the LC welding line group, and the CR welding line group.

The welding pattern for which the welding direction, sequence, and path are determined in this manner is called an operation pattern stored in advance in a database using the geometric characteristics of the registered CAD data. By selecting an operation sequence, data necessary for welding is given, and a series of operation programs is generated. Then, after confirming by an operation simulation, this operation program is transmitted to each welding robot, and the welding robot is actually operated.

[0019]

1 is a flowchart of a CAM system according to a welding robot operation program generation system according to the present invention. FIGS. 2 to 6 are steps S2 to S in FIG.
12 is a sub-flowchart in each process of FIG. Also,
FIG. 7 is a plan view showing an example of a work to be welded by this CAM system, and FIG. 8 is a side view. The work is an example of a shipbuilding panel. 7 and 8 show examples of the arrangement of works on a portable surface plate. Usually, two or more works 100 are arranged in combination. 200
Is a surface plate for setting the work 100, and the surface plate 200
The workpiece 100 is supported by the tips of a number of bar-shaped projections 201 provided thereon. When the support surface of the work 100 is curved or inclined, the protrusion 2 is formed as shown in FIG.
01 length is supported.

FIG. 9 illustrates an outline of a robot mechanism in which a plurality of welding robots are combined in one welding robot stage. An articulated robot 300 having six rotation axes each has three external axes. It is supported by a portal frame 304 in a suspended manner so that it can move up and down, left and right, and back and forth by slide mechanisms 301, 302, and 303 whose axes are orthogonal to each other. Ten welding robots 300 having nine axes in total are combined. Robot mechanism. A welding torch 1 capable of performing a known high-speed rotating arc welding is attached to the tip of each welding robot 300, which also detects the end position of the mounting member, detects a bead joint, and detects a welding line using a known arc sensor. Automatic copying control is possible. The work 100 supported on the surface plate 200 is transported below the robot mechanism by a transporting means such as a conveyor, and the welding robot 300 performs welding on the work 100. In addition, as shown in FIG. 7, region dividing lines 311, 312, 313, and 314 that define the operation region of each welding robot with respect to the workpiece 100 are set vertically and horizontally. Therefore, some of the welding lines of the mounting member are divided by these region dividing lines.

First, an outline of the shipbuilding panel will be described. The panel base material 101 of the work 100 has three panel pieces 102, 103,
104, which are connected by butt welding lines 105 and 106, respectively. It is assumed that an opening peripheral member 108 that forms the periphery of the opening 107 is attached to the center panel piece 103 in the previous step. The attachment member indicated by the reference numeral 110 is a member to be welded to the panel base material 101 in accordance with a procedure described below. Here, since each mounting member 110 has a symmetrical arrangement,
The left part from the center of the work 100 will be described. The right part will be referred to as necessary. The attachment members on the left side are represented by A, B, C,... S as shown below.
Cross members A and B are attached across three panel pieces 102-104. The vertical members C, D, E, F, G, H and the horizontal members I, J are attached to the left panel piece 102. The cross members K and L are attached across the left panel piece 102 and the center panel piece 103. The vertical member M and the diagonal members N and P, and the reinforcing member Q of the opening peripheral member 108,
R and S are attached to the center panel piece 103.

Next, a procedure for generating a welding robot operation program created for welding the work 100 as described above will be described with reference to FIGS.

(1) Reading of CAD Data (Step S1) Since the CAD system outputs the CAD data shown in Table 1 above, the CAD data is stored in a predetermined area in the CAM system.
The work shape information is sequentially read and stored while referring to the work management information in the AD output data.

(1-1) Work Management Information Work management information is used when work shape information and welding line information for a specific work are repeatedly extracted. As shown in Table 1, since the name of the assembling process is described in each mounting member, only the welding line information on the mounting member for the base material can be extracted at the corresponding welding robot stage.

(1-2) Work Shape Information Work shape information is output as data of position information from a specific work coordinate origin. This work shape information is used for checking the interference between the work and the robot in the robot simulator. FIG. 10 shows vertex data (V1 to V8) and edge line data (E1 to E8) as workpiece shape information.
12) and a method of defining plane data (F1 to F6).

(1-3) Welding line information The welding line information defines information on welding for each member. This welding line information is information serving as a basis for generating a welding robot program. When welding line information of a base material is used as the basis of welding line information as in the case of shipbuilding and bridge members, welding line information output from CAD is output only on one side (reference surface) of the member, and is output on the opposite side ( The welding line information on the back side may be generated in a welding model generation process.

(A) Member name This is the name of the mounting member.

(B) Member type Member type classification (for example, deck, trans panel,
Longines, frames, etc.). Basically, it is a classification in design, but is used as a selection parameter of a welding condition database for the purpose of determining welding conditions for each member type and controlling the welding order.

(C) Member end type The shape classification of the member end (for example, flat, scalloped,
Smip etc.). Used to determine the welding process at the end of the member.

(D) Target plane data This is used to specify which side of the mounting member is the welding line.

(E) Front and back type When the mounting line information of the base material is the basis of the welding line information as in the case of shipbuilding and bridge members, the welding line information output from CAD is one side (reference plane) of the member. Is output, and the welding line information on the opposite side (back side) may be generated in a welding model generation process. Here, the reference plane side is defined as front and the opposite reference plane side is defined as back.

(F) Welding line data Welding line numbers and welding point numbers related to the welding lines are defined. In the welding model generation processing, the basic welding line is the welding line in this unit.

(G) Processing Steps The steps in which the welding line is processed are shown. If a name other than the processing step name of the robot is described, it means that welding is performed in another step.

(H) Welding process When the welding process is changed for each welding line, a welding process name is designated. If the welding process is not a robot, even if the processing steps are the same, they are excluded from the robot.

(I) Weld point data Position data of a weld point included in a welding line. Generally, it indicates the end point of the member, but when the member is not a straight line, the change point is also output. Further, it is also output at a point where the shape (skunt ring) of the mounting member changes.

(J) Weld point type This is a type classification of the weld points. This classification characterizes the welding point. For example, it can be recognized that the scantling change point is a point used for interference check. The position where the welding point is output from the CAD is as follows. Position where welding starts or ends (example: end of member) Since the welding direction has not been determined, it cannot be determined at this stage which will be the welding start point. The position where the scan ring of the mounting member is changing The position where the mounting angle of the mounting member is changing (when the angle gradually changes, the predetermined angle pitch) The position where the mating member changes (for example, the joint portion of the base material) ) The position where the welding direction changes (other than an arc, eg a bent member) Both end positions and intermediate positions of the arc The position where the inclination angle of the welding line changes (If it changes gradually, the predetermined angle pitch) Welding Position where design information changes (eg, change point of leg length)

(K) Scan ring type This is a classification of the sectional shape of the member. By defining the member shape based on the member cross-sectional shape called scan ring, it is a major feature that the interference check with the welding torch and the robot arm can be performed more easily than the interference check using a simple three-dimensional model.

(L) Scanning data Shape data that can define the cross-sectional shape of a member. FIG.
(A) to (f) show scantling data of some member types. In the figure, L1 is the web height, L2 is the web thickness, L3 is the flange width, L4 is the flange thickness, L5
Represents the distance between the web surface and the flange end or the distance between the web end and the flange surface (in the case of a deformed member).

(M) Mounting Angle As shown in FIG. 12, the mounting angle θF of the mounting member.
By rotating the scan ring data by this angle, the shape of the mounting member in the sectional direction can be defined. Wma in the figure
x and Hmax are M in the horizontal and vertical directions at the mounting angle θF.
Represents AX scanning data.

(N) Inclination Angle As shown in FIG. 13, when the welding line is inclined, how much the welding line is inclined in the front-rear direction of the welding progress with respect to the horizontal plane (vertical inclination angle θL ) And how much the camera is inclined in the left-right direction (left-right inclination angle θT). It is a parameter for selecting welding conditions in inclined welding.

(O) Name of mating member This is the name of the mating member to which the mounting member is attached. Generally, a base material is a mating member. As an exception, other attachment members may be mating members. For example, a vertical welding line at the intersection of two attachment members. When performing an interference check, a member shape is referred to by this name.

(1-4) Welding design information Information on what kind of welding is to be performed in design.

(A) Name of welding method Classification of welding method such as fillet welding, butt welding and horizontal,
It is a classification of welding posture such as vertical.

(B) Groove Type This is a classification of groove shapes such as a groove, an X groove and a V groove.

(C) Groove data This is shape data on the classified groove shapes. When the groove type is fillet welding, the leg length is defined. FIG. 14 shows an example of fillet welding and V-shaped groove data. In the figure, θ
v is the groove angle, BL is the groove width, Ga is the root gap,
tb is the throat thickness.

(2) Generation of Work Model (Step S)
2) The work model generation process includes, as shown in FIG. 2, generation of a panel base material (step S21) and generation of an attachment member (step S22). That is, referring to the work management information in Table 1, first, a panel base material as a base is generated by connecting several base material shape data (step S21). Next, a three-dimensional three-dimensional work shape is generated by repeating the process of reading the workpiece shape information of the mounting members mounted on each base material and further reading the mounting member information that is secondarily attached to each mounting member. (Step S22). In this work model generation processing, the following processing is performed.

(2-1) Member Shape Stretching Process When a work model is generated, as shown in FIG.
0, each magnification x, X, Y, Z
The member shape is changed by designating v and w. Point P '
Is a coordinate position when the coordinates of the point P are extended by a predetermined calculation formula. This is a processing on processing in consideration of shrinkage change after welding.

(2-2) Mirror processing In the case of a work which is symmetrical with respect to a specific center line such as the shape of a ship, data conversion is performed for the symmetry line.
Generate a symmetric shape. FIG. 16 shows an example of the mirror processing.
A left-right symmetric shape is generated by inverting the left figure shape with respect to the symmetry line 10. Thereby, the data generation process can be simplified.

(2-3) Reverse Distortion Addition Processing When welding a panel-shaped work, a problem is
This is thermal deformation after welding. Normally, a straightening process is performed by a press or the like after welding, but if reverse distortion is added to the panel before welding, thermal deformation is suppressed. For this purpose, it is a process of deforming the work shape on the CAM. Specifically, a line segment that gives reverse distortion and the amount of reverse distortion are specified, and only the component in the height direction of the work is changed.

FIG. 17 is a flowchart of a processing screen in the inverse distortion adding processing. First, when a button 401 on the reverse distortion processing screen 400 is pressed, a small group name list 402 is displayed. When one small group 403 is selected from the small group name list 402, the shape 404 of the selected small group 403 is graphically displayed. Then, a reference line 40 for giving reverse distortion
5 is designated by two points Pa and Pb. Next, a point PC is designated on the inverse distortion reference line 405. Next, a window 406 for inputting the amount of reverse distortion is displayed, and the amount of reverse distortion 407 is input. A message 408 indicating that the inverse distortion processing is being performed is displayed, and the inverse distortion processing is performed. When the inverse distortion processing ends, the screen returns to the original screen 400.

FIGS. 18 and 19 show how to give the amount of reverse distortion. The inverse distortion reference line 405 is designated by two points Pa and Pb, and a position Pc on the inverse distortion reference line 405 at which reverse distortion is applied is designated. As shown in FIG. 19A, the distortion amount λc at the Pc point
Is set, for each point between the member and the welding line between Pa and Pc, the amount of strain λ according to the reverse strain reference line 405 is added in the Z direction. Similarly, a distortion amount λ corresponding to the inverse distortion reference line 405 is added between Pc and Pb. In addition, each point of the member and the welding line other than between Pa-Pc-Pb has zero strain.
In the above example, the number of intermediate points Pc between Pa and Pb is one, but a plurality of points can be specified as shown in FIG.

(3) Generation of Weld Model (Step S3) As shown in FIG. 3, the generation process of the weld model includes generation of a basic welding line (step S31), generation of a back surface basic welding line (step S32), and unnecessary processing. Deletion of welding line (step S3
3), connection of basic welding lines (step S34), and generation of welding lines (step S35). Based on the welding line information output from the CAD data, the basic necessary for robot welding for each welding line unit. This is a step of generating operation data such as a robot posture, a torch angle, and avoiding interference, and determining welding conditions.

(3-1) Generation of Basic Weld Line (Step S3)
1) One welding line is generated by joining the welding point data of the welding line information. Since a portion where the attachment member needs to be welded is recognized, this continuous line segment will be referred to as a basic welding line. Basic welding lines include not only straight lines but also arcs and broken lines.

(3-2) Generation of Back Basic Weld Line (Step S)
32) If the welding line information output from the CAD data is defined only on the surface (reference plane) of the member, the welding line information is set to the position separated by the thickness using the thickness data of the scantling data. To generate a basic welding line on the back side. Weld line information
If the back side welding line information is output, the information is read. If the back surface welding line information is not output, the back surface information is copied when the welding line is generated.

(3-3) Deletion of unnecessary welding line (step S3)
3) When the welding line information output from the CAD data includes that of a plurality of welding robot stages, or when the same stage is manually pre-welded,
Delete those welding line information. Specifically, in the following cases, the welding line is excluded from the target. Different processing steps Different welding processes

(3-4) Connection of Basic Weld Line (Step S3)
4) A welding line whose starting or ending position is the same as the other basic welding lines is connected to form a single welding line. For example, when two members having different plate thicknesses are welded in the previous process to form one attachment member, two welding lines are output from the CAD. In this case, since welding can be performed continuously, one basic welding line is used. The connection conditions and connection disable conditions of the welding line are as follows. a. Welding line connection conditions The processing steps of the two basic welding lines to be connected must be the same. The welding process of two connected basic welding lines is the same. The welding design information of two connected basic welding lines is the same. b. Conditions for disabling connection of welding lines If two or more basic welding lines are connected and the operation range of the welding robot is exceeded, connection is disabled (turning range is exceeded).

(3-5) Generation of Welding Line (Step S35) Based on the basic welding line, the welding torch posture and the basic robot posture are determined, and interference between members near the welding line and the welding robot is checked. That is, the nearby members are classified into three members, a self member, a back member, and a side member, interference with each member is checked, and interference avoidance processing is performed. As one of the interference avoiding processes, the basic welding line may be divided into a plurality of welding lines. By this interference avoidance processing, a welding line at which the welding robot can operate is determined. At that time, some new welding points are created and added. An executable welding line for robot welding that has undergone these processes is simply defined as a welding line. a. Welding point added by interference avoidance processing Point at which torch angles α and β change by interference avoidance processing Point at which welding line is divided by interference avoidance processing b. The case where the welding point is deleted by the interference avoidance process. The interference check was performed at the own member scantling change point, but it is not necessary to change the torch angles α and β. Even if the mounting angle changes, the torch angle α , Β need not be changed c. Other When the welding design information does not change even if the mating member changes

FIG. 4 shows a flowchart of the interference check process in the welding line generation process. In this interference check processing, first, an interference check of the own member (steps S351 to
S354), then, the interference check of the back member (Steps S355 to S359), and the interference check of the side members (Steps S360 to S365).

(3-5-1) Generation of Own Member Interference Check Point (Step S351) The scantling change point included in the welding line information of the attached member is generated as the own member interference check point.

(3-5-2) Determination of Torch Angle αmax (Step S352) As shown in FIG. 20, at the interference check points (change points of the scuttling) of the own member, the respective scuttling points K0 to
The interference between K12 and the welding torch outline T1 to T3 at the tip of the robot is checked, and the torch angle αmax at which any point of K contacts the line T is determined. The torch angle α is
This is the angle of inclination of the welding torch 1 with respect to the horizontal plane. α is
It is in the range of 22.5 ° to 90 °. In the case of fillet welding, α is generally 45 °.

(3-5-3) Determination of Basic Robot Posture (Step S353) When the torch angle changes as a result of the interference check, the position of the connection point between the robot arm 305 and the welding torch 1 also changes. Therefore, using the torch angle αmax, as shown in FIG. 21, the torch connection point r1 of the arm outline approximation line segment R1 in the basic robot posture is corrected for the own member.

(3-5-4) Checking for Interference with Own Member (Step S 354) Using MAX scanning data of the own member to check for interference with arm outline approximation lines R 1 and R 2, and to make interference Check with the following basic robot posture. Here, the basic robot posture refers to a posture defined in a plurality of forms as shown in FIG. 22, and is a robot posture that can correspond to a depth depth by an attachment angle of an attachment member or the like. The range of the shaded portion 310 in FIG. 22 is the interference range between the robot arm and the workpiece in the basic robot posture. In the figure, Ti and To are the inner and outer ridges of the welding torch 1, Ri1 and Ri2 are the inner lines of the robot arm 305, and Ro1 and Ro2 are the outer lines of the robot arm 305.

The basic robot posture is the welding torch 1
The horizontal offset amount LH between the tip of the robot arm 305 and the center of the support block 306 of the robot arm 305 is determined to three types, and the respective basic postures are set. At the time of the interference check, first, the presence or absence of interference is checked in the basic robot posture, and in the case of interference, the check is performed in the next basic robot posture.
If there is further interference, the robot is checked in the basic robot posture. If the interference still cannot be avoided, the welding line is divided at that point, and the division point is additionally generated as a new welding point. By limiting the basic robot postures to some, automatic interference avoidance processing on a computer is enabled.

(3-5-5) Selection of Interference Candidate Member of Back Member (Step S355) Next, the robot back member is set to the basic robot posture determined as a result of the interference check with its own member. Select an interference candidate member. For this purpose, first, as shown in FIG. 23, an area for extracting an interference candidate member is set around the own member, and a member covering this area is set as an interference candidate member. In FIG. 23, Wc1 × Lmc is a region for extracting a back surface interference candidate member when the basic robot posture is set, and Wc2
× Lmc is a region for extracting a back surface interference candidate member when the basic robot posture is set. Although the area for extracting the rear interference candidate member in the basic robot posture is not shown,
Similarly, an area of Wc3 × Lmc can be set.
Lsc and Les are areas for extracting interference candidate members as side members, which will be described later. Lc is the total length of the extraction area, and t is the plate width (including the flange width) of the own member.

(3-5-6) Generation of Interference Check Point of Back Member (Step S356) When a candidate interference member on the back surface is extracted by the above method, the scantling change point of the interference candidate member is extracted. , A perpendicular to the welding line of the member is lowered, and an intersection with the perpendicular is generated as an interference check point. For example, in the case where the determined basic robot posture is, the members covering the region Wc1 are the B member and the D member in FIG. Therefore, B
From the scantling change point Kb1 of the member to the welding line 1 of the member
The intersection P1 with the perpendicular drawn down to 20, and the connection points P3 and P4 between the D member and the own member are generated as interference check points.
When the basic robot posture is determined, the interference candidate members become the B member, the C member, and the D member, and the interference check points are lowered from the P1 of the B member and the scantling change point Kc1 of the C member. The point of intersection P2 with the perpendicular is the point P3, P4 of the D member.

(3-5-7) Determination of Torch Angle αmin (Step S357) At each of the above interference check points, as shown in FIG. 25, torch outlines T4 and T5 and scantling point K0.
To K3, and the torch angle .alpha.min at which any point of K contacts the line segment T is determined.

(3-5-8) Interference Check with Back Member Based on Basic Robot Posture (Step S358) As in step S353, using the torch angle αmin, as shown in FIG. The torch connection point r4 of the line segment R3 is corrected, and the line segments R3, R
An interference check between 4 and the back member selected as the interference candidate member is performed at each interference check point.

(3-5-9) Determination of Torch Angle α (Step S)
359) αmax at each interference check point (scanning change point) obtained by interference check with own member and back member,
The torch angle α is determined from αmin. That is, αmin
If ≦ 45 ° ≦ αmax, the torch angle α = 45 °. This angle is the standard torch position that ensures stable quality in fillet welding. In addition, the above-described interference check processing may result in a case where the basic robot posture cannot be obtained,
If the torch angles αmin and αmax are inappropriate values for welding, for example, αmax <22.5 ° and αmin> 60 °,
The basic weld line is divided at the interference check point.

(3-5-10) Selection of Interference Candidate Member for Side Member (Step S360) In FIG. 23, the members extracted as the interference candidate members for the side member are the start end region Lsc or the end end region Lec. A member hung on two regions Lsc and Wci (i = 1 to 3) or Lec and Wci. However, the member has been subjected to the interference check as described above as an interference candidate member of the back member,
As a result of the interference check processing, if no interference occurs, it means that there is no interference with the side member, and the side member is not selected. However, since this member is related to the start or end of the welding line of its own member, if interference occurs, it is further selected as a side member, and the following interference check is performed.

(3-5-11) Generation of Interference Check Point of Side Member (Step S 361) As shown in FIG. 26, when A is the own member and B is the extracted side member as an interference candidate member, Member B has already been checked for interference as a back member, and here interference occurs at point P1. That is, the member B
From the point P2 where the end point B0 of the welding torch 1 is projected on the own member A, the point Bc at which the torch outline comes into contact with the member B when the posture of the welding torch 1 is moved while maintaining α = 45 ° and β = 0 °. The intersection P with the perpendicular drawn from the point Bc to the own member A
By obtaining 1, P1 is generated as an interference check point.

(3-5-12) Adjustment of Torch Angle γ (Step S)
362) At the interference check point P1, the torch angle γ is adjusted so that the welding torch 1 is parallel to the inclination of the side member B as shown in FIG. This torch angle γ is shown in FIG.
As shown in FIG. 8, the adjustment is performed by rotating the joint shaft 307 of the first robot arm 305a and the second robot arm 305b.

(3-5-13) Adjustment of Torch Angle β (Step S
363) As shown in FIG. 26, the torch angle β is adjusted so that the welding torch 1 is parallel to the surface of the side member B at the interference check point P1. Here, the torch angle β is the angle of inclination of the welding torch 1 in the horizontal plane with respect to the welding line, and generally β = 0 °, but β is changed within a range of −45 ° to + 45 ° at a location where there is a risk of interference. .

(3-5-14) Check for Interference with Own Member and Side Member (Steps S364 and S365) At each point of P0 and P1, own member A and side member in the torch postures of α, β and γ described above. Check for interference with B.

Checking interference with own member When welding torch 1 is moved from point P1 to point P0 with torch angle α determined as described above, welding torch 1 may interfere with own member A. For example, as shown in FIG. 29 which is a view taken in the direction of arrow a in FIG. 26, when the flange width or the web height of the own member A changes in this section, interference occurs. Accordingly, when interference occurs, α is corrected to 45 ° or less or 45 ° or more within the range of αmin and αmax obtained as described above. If the corrected value of α is smaller than the allowable lower limit value or larger than the allowable upper limit value, the point P1 is generated as a welding end point (weld stop point).

Checking for Interference with Side Member Even if the torch angles β and γ adjusted as described above, P
The welding torch 1 may interfere with the side surface member B as shown in FIG. FIG. 30 shows FIG.
FIG. If such interference occurs, β is changed within the above-mentioned angle range. If β does not fall within the allowable angle range, the point P1 is generated as a welding end point (a welding stop point).

Table 2 shows the results of the interference check and the presence and absence of interference at points P0 and P1.

[0077]

[Table 2]

Since a plurality of works are arranged on the surface plate 200, the above processing of steps S1 to S3 is repeated n times (see FIG. 1).

(4) Generation of Cell Model (Step S4) As shown in FIG. 5, the cell model generation process selects the target work (Step S41), arranges the work (Step S42), and divides the area (Step S43). ), Generation of a welding line (step S44), selection of a twin welding line (step S44).
45), determination of the welding direction (step S46), determination of the welding order (step S47), and determination of the welding path (step S48).

(4-1) Selection of Target Work (Step S4)
1) From the work management information in Table 1 above, select a work to be welded.

(4-2) Arrangement of Work (Step S42) A work to be welded is arranged on a cell model composed of the following robot arrangement data. a. Robot arrangement data Origin position of each robot in the system coordinate system: ROBOT1
(X1, T1, Z1) ··· The operating area of the external axis in the system coordinate system: (X1, Y1, Z1,
X2, Y2, Z2, X3, Y3, Z3, X4, Y4, Z4) Robot's area dividing line in the system coordinate system: (X1, Y
1, Z1, X2, Y2, Z2, X3, Y3, Z3, X4, Y4, Z4) Width of overlap area

B. Automatic work placement processing Checks whether the work outline approximation rectangle fits within the rectangle indicating the robot operation area. As the workpiece approximate outer shape, a right triangle may be considered in addition to the quadrangle. In this case, the same processing is performed. When a plurality of work sets are possible in the square of the surface plate, a setting with a small number of divisions of the basic welding line by the region dividing line is selected.

FIG. 32 is a flowchart of the automatic work placement processing. First, the selected n works are read from the work list (step S421). Next, for example, in the case of a work shape as shown in FIG. 33A, the base material vertices B1 and B1 are obtained from the base material vertex data as shown in FIG.
The coordinates of 2, B3, and B4 are obtained (step S422), and the approximate line segments B1, B2, B2, B3, B3, B4, and B4B1 are obtained (step S423).
近似 B4 is determined (step S42).
4). However, squares whose outlines extend outside the square are excluded. In the case of FIG. 33 (a), the line segment B3 B4 has a convex outer shape, which makes it difficult to arrange the work. Therefore, a square based on this line segment is excluded. Then, the one having the smallest area as shown in FIG. 3C is selected as the optimum approximate outer shape (step S425). The length of the long side of the work approximating rectangle is set as BL, and the length is compared with the platen area size to determine the setting of the work (step S426).

In step S427, the squares included in the surface plate are classified into the following three cases. FIG. 34 shows the outer shape of the surface plate 200 and the element squares of the surface plate included therein. RW and RL are the horizontal and vertical widths of the element rectangle. As shown in FIG. 34, for the element rectangles A to E, the long side length BL and the platen width R of the work approximation rectangle in order.
The work setting is determined by comparing W and RL (steps S428 to S430). Case 1: BL ≦ RW At this time, the work is set horizontally in the A element as shown in FIG. Case 2: RW <BL ≦ RL In this case, the work is set vertically in the A element as shown in FIG. Case 3: RL <BL In this case, since it does not fit within the A element, it is compared with the next element rectangle B as described above.

Next, in the work setting determined as described above, it is checked whether there is any welding line outside the robot operation area (step S431). When the welding line protrudes from the robot operation area, the work approximate rectangle is shifted in parallel so as to enter the operation area.

The recalculation of the surface area in step S432 is performed as follows. As shown in FIG. 36, there are eight types of squares A to H that can be considered in the L-shaped surface plate remaining after one work is set. A to H
Sorts in ascending order of RL and determines the order. The above steps S428 to S433 are repeated n times for the number of selected works.

(4-3) Region Division (Step S 43) A plurality of welding robots capable of performing the same work in a finite work area are arranged, and in order to complete the work in the shortest time, individual It is desirable to level the workload of the welding robot. However, the individual robots are
In the case where the robot is arranged in a suspended manner as shown in FIG. It is divided into two areas: a work area (unique area) assigned to each limited robot, and an area (lap area) that can be assigned to adjacent robots. FIG. 37 shows a flowchart of the dividing process of the work area of the robot.

First, the average load of each ideal robot in the work area is calculated by the following equation (step S434). Ave. = (Total work amount) / (number of robots) Next, as shown in Table 3, the work amount of the unique region and the work amount of the lap region are obtained (steps S435 and S436).

[0089]

[Table 3]

Next, the work amount of the lap area is divided as shown in FIG. 38, and each robot is assigned (step S4).
37). In FIG. 38, a = Ave. -FL1 b = FL1 -a a2 = Ave. −FL2 ′ (where FL2 ′ = FL2 + b) b2 = LL2−a2

After the processing in step S437, the workload of the robot is Ave. If there is more than two robots, there are two adjacent robots. However, the robot No., which is the start of the processing, 1 and 1 if the last robot is at its peak. If there are three or more peak robots, the work amount dividing process in step S439 is not performed. Therefore, in step S438, it is determined how many peak robots exist after the processing in step S437, and only when there are two robots, the work amount is divided as described below (step S439). FIG.
Example 9 shows a case where two peak robots exist.

Ave. Is obtained from the following equation. Pv = Σ (FLn-ave.) Next, the average value Pave is obtained from the following equation. Pave = Pv / 3 Attention is paid to the peak robot having the largest amount of work in the unique area (the robot No. 3 in the example of FIG. 39 corresponds to this). Here, the difference of the movable lap area is obtained from Pave, and the work amount is sequentially moved as shown in FIG. Further, in step S440, the number of peak robots after the work amount division processing is determined, and the above processing is repeated only when the number is two. As described above, the workload of the robot is leveled.

(4-4) Generation of Welding Line (Step S44) When the welding line is divided by an area dividing line representing the operation area of the welding robot, the division point is generated as a welding point. Therefore, one basic welding line is composed of a plurality of welding lines.

FIG. 41 shows a region dividing line 311 of the welding robot.
14 shows an example of a work 100 divided by 314.
Here, one work 100 is divided into eight regions. In the drawing, reference numeral 120 denotes a welding line of each mounting member.

(4-5) Selection of Twin Weld Line (Step S4)
5) After the weld line has been generated as described above, the twin weld lines are:
Selected only if the following criteria are met: The length of the welding line on both sides of the mounting member must be the same. The welding design conditions must be the same. The two welding robots do not interfere with each other. For welding lines that do not satisfy the above three conditions, a single welding line is selected.

(4-6) Determination of Welding Direction (Step S46) The welding direction is determined for each welding line in the divided area generated as described above. The rules for determining this welding direction are:
For example:

Rule R1: The welding direction is set such that the end that can be detected by the arc sensor is the welding end point (end). Since the allowable range of the end detection sensor (arc sensor) has a restriction that the basic torch angle β is within ± 45 °, the side where the basic torch angle β at the end of the welding line falls within this range is set as the welding end point. . For example, in the case where another mounting member 113 is connected to one side of the mounting member 110 as shown in FIG. 42 (a), the torch angle β is set so as to avoid interference between the welding torch 1 and the work. The member 113 is greatly inclined with respect to the welding line (β> 45 °). On the other hand, since the opposite end has no interference, the torch angle β is within the allowable range of the end detection sensor. Therefore, with respect to the mounting member 110, the end on the mounting member 113 side is the welding start point WS, and the end on the side without interference is the welding end point WE, and the welding direction is determined in the direction shown by the arrow. . On the other hand, as shown in FIG. 42 (b), when the attachment member 110 is sufficiently separated from the attachment member 113, either of them may be set as the welding start point. In such a case, a rule R4 described later is used. Is used to set the welding direction in a counterclockwise direction with respect to the mounting member 110. In this case, turning welding may be performed at the end of the mounting member 110. When turning welding is performed, the welding start point and the welding end point match.

Further, as another example, when a plurality of welding lines are present on one side of the mounting member, for example, as shown in FIG. 43, the mounting member 110 is connected to the other mounting members 114 and 115. In such a case, three welding lines 121, 122, and 123 (for the sake of convenience in the following description, the symbols that represent the welding line and the welding direction at the same time) are present on one side of the mounting member 110. In such a case, the welding directions of the welding line 121 and the welding line 123 are divided into a clockwise direction and a counterclockwise direction according to the above rule R1. On the other hand, since the welding line 122 is outside the allowable range of the terminal detection sensor on both sides, the welding direction is not determined. Also in such a case, the welding direction is set to the counterclockwise direction with respect to the mounting member 110 using the rule R4 described later.

Rule R2: When one or both of the welding lines are to bead joints, the welding direction is a direction from the side closer to the robot system coordinate origin to the side farther. This is, for example, when one welding line is divided due to interference or the like even within the same welding robot operation area as shown in FIG.
When the connection of 123 is possible, the welding direction is defined as one, so that the bead joints 141 and 142 can be welded in one way to stabilize the welding quality. In the example of FIG.
Since the other mounting members 116 and 117 connected to 10 are provided with scallop portions 118, beads can be spliced through the scallop portions 118.

Rule R3: When one or both of the welding lines are divided by a region dividing line that defines the operation region of the welding robot, the welding direction of the welding line is directed from a side closer to the robot system coordinate origin to a side farther away. Direction. This is because, as shown in FIG. 45, one attachment member 110 extends over a plurality of operation regions of the welding robot, and the welding lines 121 to 123 and welding lines 124 to 126 on both sides are divided by region dividing lines 311 and 312. In such a case, by defining the welding direction in one direction, the welding quality of the bead joint at the region division points 151 and 152 is stabilized.

Rule R4: If the welding direction is not uniquely determined by the rules of R1 and R2, the welding direction of the welding line is assumed to be a counterclockwise direction. The above rules are applied in the order of R3 → R2 → R1 → R4.

(4-7) Determination of Welding Order (Step S47) The principle rule Ra for determining the welding order is as follows. First, the surface including the welding line whose welding start point is closest to the robot system coordinate origin in the mounting member is determined. That is, it is determined which of the front and back sides of the mounting member is to be welded first. In order to determine the surface including the welding line to be welded first, it is determined whether or not the normal vector of the surface is directed to the robot system coordinate origin.
For example, in FIG. 43, the robot system coordinates OXY
Is taken as shown, the surface 110 of the mounting member 110
The normal vector Va perpendicular to a is directed toward the robot system coordinate origin O (X component Va of the normal vector Va).
Since the sum of x and Y component Vay becomes a minus sign, it is directed toward the origin O). On the other hand, the back surface 1 of the mounting member 110
The normal vector Vb perpendicular to 10b points in the direction opposite to the robot system coordinate origin O (the sum of the X component Vbx and the Y component Vby of the normal vector Vb is a + sign, Become). Therefore, the mounting member 11
For 0, the welding line included in the surface 110a is first welded. Next, welding is started with the welding line whose welding start point is closest to the robot system coordinate origin O as the first place among the welding line group included in the surface. In the example of FIG. 43, among the welding line groups 121 to 123 included in the surface 110a,
Since the welding line at which the welding start point WS is closest to the robot system coordinate origin O is the welding line 121, the welding line 121 is welded first. Therefore, the welding order is the surface 110a.
Welding line 121 → welding line 122 → welding line 123 →
The order of the welding lines 124 on the back surface 110b is determined.

Further, the following rules are applied. Rule Rb: The side with the groove is welded first. This rule is to minimize the occurrence of defects such as blowholes caused by the primer, such as when the groove is coated with a primer. For example, FIG.
In the case of the mounting member shown in FIG. 6, the groove 112 side (left side)
Are welded first.

(4-8) Determination of Welding Route (Step S48) Based on the welding direction and welding order for each welding line determined above, interference between the welding robots should be minimized.
The welding path is determined so that the air cut time is as short as possible. In the case of a multi-robot, minimizing interference between welding robots is an important factor for improving the arc time rate. As shown in FIG. 47, the specific processing includes an interlock area setting means 481 for avoiding interference, a welding line selecting means 482 for selecting a welding line included in the set interlock area, and The welding path determination means 483 determines a welding path for each welding line. As a method of avoiding interference between the welding robots, the welding robots perform welding while taking an interlock (synchronization) for each of the above-described regions, thereby minimizing the probability that two welding robots will simultaneously enter adjacent regions. I keep it low.

Interlock area setting means The setting of the interlock area for avoiding interference depends on the number of welding lines included in the operation area of the welding robot.
In the interlock area setting means 481, of the two division methods as shown in FIG. 48, the welding line included in the R area (the right or upper interlock area in the operation area of the welding robot) is the most. Choose a splitting method that will increase. In the method shown in (a), focusing on the interference between the left and right welding robots, the operation area of each welding robot is divided into three in the vertical direction, and the hatched portions on each right side are interlocked areas 321, 322, and 323. It is set as. On the other hand, the method shown in (b) focuses on the interference between the upper and lower welding robots, divides the operating area of each welding robot into three parts in the horizontal direction, and interlocks the interlock area in the upper hatched part in the lower area. 324 is set. The division ratio of the operating region of the welding robot is usually equal, but may be different depending on the work. In the example of FIG. 48, the welding line length included in the method (a) is longer than the welding line length included in the method (b).
The method (a) in which the probability of occurrence of the interference problem is high is adopted.

Welding line selection means As shown in FIG. 49, the welding line selection means 482 provides three regions in the operation region of the welding robot, and classifies the welding lines for each region. Specifically, a welding line group (LCR welding line group) extending over three regions of L, C, and R; a welding line group (LC welding line group) included in one or both of the two regions of L and C; It is classified into a welding line group (CR welding line group) included in one or both of the two regions C and R.

Welding path determining means The welding path is determined in the order of the LCR welding line group, the LC welding line group, and the CR welding line group. At the time of actual welding, the interlock is taken for each area by the welding robot group control system. The welding path for each area is selected so that the air cut is minimized. Specifically, start from the mounting member whose welding start point is closest to the robot system coordinate origin, and select another mounting member with the welding start point closest to the welding end point of the last welding line of that mounting member. repeat.

The relationship between the welding path and the interlock is shown in FIG.
Shown in Referring to this figure, first, step S
In the welding of the 481 LCR welding line group, it is checked whether the LCR welding line group exists in the operation area of the welding robot. If the LCR welding line group exists and the LCR welding line group also exists in the left welding robot adjacent to the left side of the welding robot, the welding is waited until the left welding robot completes welding (welding is not started). If the left welding robot is waiting for the interlock, no interference occurs between the left and right welding robots, and the welding of the welding robot is started. Next, LC
When the R welding line group does not exist and the LC welding line group exists, when the welding of the LCR welding line group of the left welding robot is completed, the welding of the LC welding line group of the welding robot is started (step). S482). Finally, if neither the LCR welding line group nor the LC welding line group exists in the welding robot and the CR welding line group exists, if the welding of the LC welding line group of the right welding robot is completed, the welding robot (Step S483). Then, in the welding of each welding line group, welding is started from a mounting member having a welding start point closest to the robot system coordinate origin, and from the welding end point of the last welding line of the mounting member to the welding end point most. Move to another mounting member with a closer welding start point.
This minimizes air cut.

(5) Generation of operation program (step S
5) As shown in FIG. 6, the processing for generating the operation program includes selecting an operation pattern (step S51), checking for interference based on the operation pattern (step S52), generating a welding line for avoiding interference (step S53), and selecting an operation pattern. (Step S54), selection of welding conditions (Step S5)
5) and generation of an operation program (step S56).

(5-1) Selection of Operation Pattern (Step S5)
1) Based on the member shape characteristics at each welding point of the welding line generated for each mounting member, an operation pattern that seems to be optimal is sequentially selected and assigned. Here, the member shape characteristic is the upper part that specifies the welding operation at each welding point such as the presence or absence of a side member at the end of the welding member. The basic operation pattern is
It is related to approach, starting end detection (touch sensing), starting end / intermediate / end end welding, end detection (arc sensor), retract, wire cut, nozzle cleaning, and air cut. Then, a management table of these basic operation patterns is provided, and an optimal execution pattern is selected and allocated.

(5-2) Interference Check by Operation Pattern (Step S52) It is checked whether or not the welding robot does not interfere with its own member and adjacent members at a specific position in the operation sequence allocated as described above. At the time of this interference check, a check is made with the basic robot posture having the torch angles α and β determined as described above.

(5-3) Generation of Welding Line for Avoiding Interference (Step S53) In the interference check in the above step S52, the welding line having interference with its own member and the adjacent member is treated as a fixed process. The interference is avoided by shortening the welding line to a position where no interference occurs in the operation pattern. Basic motion pattern (robot posture) assigned to avoid interference
In principle, we do not change this. This is because if the basic operation pattern is changed, it becomes difficult to secure the welding quality.

(5-4) Development of Operation Pattern (Step S5)
4) The assigned operation pattern is developed according to the welding path determined in step S48. The processing is
The position of each operation sequence point is calculated and obtained from the member position data.

(5-5) Selection of welding conditions (step S55) Welding conditions are assigned to each welding line on the welding path. For example, the welding condition data code in the case of horizontal fillet welding is described as shown in FIG. The codes of the respective elements are set in sub-tables as shown in FIGS. 7B to 7G, and the optimum code corresponding to the property of the welding line is set at the position of the welding condition code in the welding condition data bank. The welding conditions are stored.

(5-6) Generation of Operation Program (Step S
56) As described above, welding line data for the work 100 is created, and this is edited as an operation program of the welding robot.

(6) Operation Simulation (Step S)
6) Simulate the operation of the welding robot with the above operation program, and finally check whether there is any problem. After that, this operation program is transmitted to each welding robot, and provided for actual welding.

FIG. 52 shows a specific example of the welding path. The origin O of the robot system coordinates is set at the lower left corner of the surface plate 200, and the L, C, and R regions are set according to the method shown in FIG. As shown in FIG. No. 1 to No. Shown at 8. 53 to 56 show NO. 1 to NO. The weld line in the area of No. 4 is shown in a sectional view. The welding line of each mounting member is shown by adding a numeral to the lowercase alphabet. In the figure, 151
Reference numerals 168 denote area division points on the left side of the workpiece 100.

First, the welding robot NO. In region 2, since the LCR welding line group includes the divided welding line of the J member, the welding path is set to the welding lines j1, j2, j in a counterclockwise direction.
3, j4. Next, since the LC welding line group includes the divided welding lines of the C member, the welding routes are c1, c2, c
The order is 3. Finally, since the CR welding line group includes the division welding line of the B member and the welding lines of the G and H members, the welding path is defined by the welding lines b1, b2 counterclockwise from the B member near the robot system coordinate origin O. , B3, b4, and then move to the G member based on the rule of the minimum air cut, and counterclockwise turn welding lines g1, g2, then the welding line h of the H member.
1, then h2.

Next, the welding robot NO. In area 1,
Since the LCR welding line group includes the split welding line of the I member,
The welding path is in the order of i1, i2, i3, and i4 in the counterclockwise direction, and then in the order of the divided welding lines c4, c5, and c6 of the C members included in the LC welding line group. Finally, among the A, E, and F members included in the CR welding line group, the welding lines e1, e2, and then the A member are moved from the E member near the robot system coordinate origin O to the divided welding lines a1, a2, a3. , A4, and finally the welding lines f1, f2 of the F member.

In the area of the welding robot N0.4, the LCR
Since the welding line group includes the divided welding lines of the B member, the welding paths are in the order of b5, b6, b7, b8, and then LC
Since the welding line group includes the divided welding lines of the J and D members and the welding line of the L member, first, the welding lines j5 and j6 are moved from the J member near the robot system coordinate origin O to the D member, and the welding lines are moved. d1, d2, d3, d4, and then the welding lines l1, l2 of the L member. Finally, since the M and P members are included in the CR welding line group, the divided welding lines m1,
The order is m2, m3, m4, and the welding line p1 of the P member. The back side of the P member is not welded. Further, twin welding lines r1, r2, s1, and s2 are selected for the R and S members, respectively. The twin welding lines r1 and r2 of the R member are the welding robot NO. 4 and NO. 3 perform welding in synchronization with each other, and the twin welding lines s1 and s2 of the S member are set to the welding robot NO. 4 and N
O. 6 performs welding in synchronization.

The welding robot NO. In region 3, LCR
Since the welding line group includes the division welding line of the A member, the welding paths are in the order of a1, a2, a3, and a4, and then the LC welding line group has the division welding lines of the I and D members and the K member. Since the welding line is included, first, the divided welding lines i5 and i6 of the I member, and then to the D member, and the divided welding lines d5, d6, d7, d
8, and then the welding lines k1 and k2 of the K member. Finally, since the CR welding line group includes the M member split welding line and the N member welding line, the M member split welding lines m5, m6, m
7, m8, and then the welding line n1 of the N member. The back side of the N member is not welded similarly to the P member. Q and R members are twin welding lines q1 and q in the same manner as above.
2, r1 and r2 are selected. In the same manner, the welding path of the welding line for the right portion of the
Is determined as shown in FIG.

After the welding of the panel base material and each mounting member is completed as described above, a vertical welding line is welded to join the mounting members. The vertical weld line is
In the operation area of each welding robot, welding is performed in ascending order from a welding line close to the robot system coordinate origin.

[0123]

As described above, according to the present invention, CAD /
Using only the workpiece shape information and welding design information of the CAD data registered in the CAM system, operation programs for a plurality of welding robots can be automatically generated,
Automatic welding of large-sized workpieces with complicated three-dimensional shapes can be performed with high efficiency and high quality. In addition, since the cross-sectional shape data of the mounting member (scanning data) and the basic robot postures fixed to a plurality of types are used to check for interference between the mounting member and neighboring members in the vicinity thereof, a complicated three-dimensional shape can be obtained. There is an advantage that interference check can be easily performed.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a procedure for generating a welding robot operation program according to the present invention.

FIG. 2 is a flowchart in a work model generation process of FIG. 1;

FIG. 3 is a flowchart in a welding model generation process of FIG. 1;

FIG. 4 is a flowchart of an interference check process in the welding line generation process of FIG. 3;

FIG. 5 is a flowchart in a cell model generation process of FIG. 1;

FIG. 6 is a flowchart in an operation program generation process of FIG. 1;

FIG. 7 is a plan view showing an example of a work.

FIG. 8 is a side view of FIG. 7;

FIG. 9 is a schematic diagram of a robot mechanism including a plurality of welding robots.

FIG. 10 is an explanatory diagram of a method of defining each data of work shape information.

FIG. 11 is an explanatory diagram of a method for defining scanling data of various attachment members.

FIG. 12 is an explanatory diagram of a method of defining MAX scanning data.

FIG. 13 is an explanatory diagram showing a vertical inclination angle and a horizontal inclination angle of a welding line.

FIG. 14 is an explanatory diagram of a method for defining groove shape data.

FIG. 15 is an explanatory diagram of a member shape extending process.

FIG. 16 is an explanatory diagram of mirror processing of a member shape.

FIG. 17 is a flowchart of a reverse distortion addition processing screen.

FIG. 18 is an explanatory diagram of a method for giving an inverse distortion amount.

FIG. 19 is an explanatory diagram of a method for giving an inverse distortion amount.

FIG. 20 is an explanatory diagram of a method of determining a torch angle αmax by checking an interference with the own member.

FIG. 21 is a diagram illustrating an outline of a robot arm.

FIG. 22 is an explanatory diagram of a basic robot posture.

FIG. 23 is an explanatory diagram of an extraction area of an interference candidate member.

FIG. 24 is an explanatory diagram of interference check points.

FIG. 25 is an explanatory diagram of a method of determining a torch angle αmin by checking interference with a back member.

FIG. 26 is an explanatory diagram of an interference check method for a side member.

FIG. 27 is a view showing that a welding torch is inclined in parallel with the side member in the interference check with the side member.

FIG. 28: α, β, γ of welding torch and robot arm
It is explanatory drawing of a shaft.

FIG. 29 is a view as seen from the arrow a in FIG. 25.

30 is a view as viewed in the direction of the arrow b in FIG. 25.

FIG. 31 is an explanatory diagram showing a method of repeatedly checking between the end portions P0 to P1 of the own member in the interference check with the side member.

FIG. 32 is a flowchart of an automatic work placement process.

FIG. 33 is an explanatory diagram of a method of generating a work approximate rectangle in the automatic work placement processing.

FIG. 34 is an explanatory diagram of an element square of a surface plate in the automatic work placement processing.

FIG. 35 is an explanatory diagram of a method of arranging element squares and a work approximate square on a surface plate.

FIG. 36 is an explanatory view showing a method of arranging the surface plate on the remaining portion after arranging one work.

FIG. 37 is a flowchart of a process of dividing a work area of the welding robot.

FIG. 38 is an explanatory diagram of a method of dividing the work amount of the welding robot.

FIG. 39 is an explanatory diagram of a method for leveling the work amount of the welding robot.

FIG. 40 is an explanatory diagram of a method for leveling the work amount of the welding robot.

FIG. 41 is a plan view showing a welding line of each mounting member on the work.

FIG. 42 is an explanatory diagram showing a start end and an end of a welding direction.

FIG. 43 is an explanatory view showing the welding direction and the order of the attachment members.

FIG. 44 is an explanatory diagram showing a welding direction and an order when connection of a welding line is possible.

FIG. 45 is an explanatory diagram showing a welding direction and an order when a welding line is divided.

FIG. 46 is an explanatory view of a mounting member having a groove.

FIG. 47 is a block diagram of means for determining a welding path.

FIG. 48 is an explanatory diagram showing a method of dividing the operation area of the welding robot.

FIG. 49 is an arrangement diagram of L, C, and R regions according to the dividing method of FIG. 47;

FIG. 50 is a flowchart for determining a welding path based on welding lines in the L, C, and R regions and an interlock of a welding robot.

FIG. 51 is an explanatory diagram of welding condition data names of horizontal fillet welding lines and respective optimum welding condition tables.

FIG. 52 is an explanatory diagram of a welding path of a work.

53. FIG. It is a division diagram of two areas.

54. FIG. FIG. 3 is a partial view of one area.

55. FIG. It is a division diagram of four areas.

56. FIG. It is a division diagram of three areas.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Welding torch 100 Work 101 Panel base material 110 Mounting member 120 Basic welding line 200 Surface plate 300 Welding robot 305 Robot arm 311 to 314 Area division line

Claims (13)

[Claims] When a workpiece having a plurality of mounting members is welded by a plurality of welding robots, a CAD / C is used.
A system that reads data registered in an AM system and automatically generates an operation program of each of the welding robots; a unit configured to generate a work model corresponding to the work from work shape data of the read data; Means for generating a welding model having a basic welding line consisting of attachment lines of components of the workpiece; and a cell model by dividing the work model by a region dividing line so as to equalize the workload of the plurality of welding robots. Means for generating whether or not the workpiece and the welding robot interfere with each other for each of the basic welding lines, and generating a welding line in a range in which no interference occurs; and an area divided by the area dividing line. Direction, welding order, and welding conditions for all the weld lines after the interference check included in that area. Means for deciding a path, and for the determined welding line, assigning data necessary for welding by selecting an operation sequence group called an operation pattern obtained in advance from the data, a series of operation programs And a means for generating a welding robot operation program. 2. The interference checking means fixes a basic robot posture to a plurality of types, and performs an interference check on an interference candidate member extracted from the mounting member and its peripheral members according to the basic robot posture. 2. The system according to claim 1, further comprising means for determining a torch angle. 3. The interference checking means sets an area for extracting the interference candidate member on the back side and the side surface of the mounting member, and sets the cross-sectional shape data of the interference member on the mounting member and the extraction area. 3. The system for automatically generating a welding robot operation program according to claim 2, wherein the system is configured to check for interference by using a program. 4. The apparatus according to claim 1, wherein said interference checking means has means for generating a welding stop point on a welding line when interference occurs as a result of the interference check.
An automatic generation system for a welding robot operation program according to claim 2 or 3. 5. The automatic system according to claim 1, further comprising means for selecting a twin welding line when the generated welding line satisfies a predetermined condition. 6. An interlock area setting means for setting an interlock area for avoiding mutual interference of the welding robots, and a welding line included in the set interlock area. The system for automatically generating a welding robot operation program according to claim 1, further comprising welding line selection means. 7. The welding robot according to claim 1, wherein, when the welding direction with respect to the mounting member is determined by the welding direction determining means, the end of the welding line is set so that the end position can be detected by an arc sensor. Automatic operation program generation system. 8. A welding line divided by the region dividing line, or a welding line divided by another mounting member connected to the mounting member, wherein the welding line can bead jointed. 8. The system according to claim 7, wherein the welding direction determining means sets the same welding direction. 9. The method according to claim 7, wherein when the welding direction determining means determines a welding direction with respect to the mounting member, the welding direction is a counterclockwise direction with respect to the mounting member. 8. An automatic generation system for a welding robot operation program according to item 8. 10. When the welding sequence determining means determines the welding sequence for the mounting member, first, a surface including a welding line whose welding start point is closest to the robot system coordinate origin is determined on the mounting member. 2. The system for automatically generating a welding robot operation program according to claim 1, wherein a welding order in which a welding start point of the group of welding lines in the plane is closest to the origin of the robot system coordinates is set as a first order. 11. The welding sequence determining means gives priority to a welding line on a side having a groove or a wide angle side of a mounting angle for a mounting member having a groove or a slope. Automatic generation system of the described welding robot operation program. 12. The interlock area setting means,
When the operation area of the plurality of welding robots is divided into three in the vertical or horizontal direction, a division direction is selected such that the welding line included even in a part on the right side or the upper side is the largest, and the division direction is selected according to the selected division direction. 7. The automatic generation system according to claim 6, wherein the right or upper area is set as an interlock area. 13. The welding line selecting means, when the operating region of the welding robot is divided into three in the selected dividing direction, a welding line group (LCR welding line group) extending over three regions, A welding line group (LC welding line group or CR welding line group) included in one or both is selected, and the LCR welding line group, the L
The welding robot operation program automatic generation system according to claim 6, wherein a welding path is determined in the order of the C welding line group and the CR welding line group.