JP2010205139A - Method for eliminating hole of three-dimensional shape data - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily and quickly select and eliminate a hole shape irrelevant to welding when the hole shape is included in three-dimensional shape data. <P>SOLUTION: This method for eliminating a hole of three-dimensional shape data designates a surface forming an inner side of a hole shape in a work graphic displayed on a display screen extracts an adjacent surface as a continuous surface if an angle between the surface designated in an inner surface designation step and the adjacent surface is within the range of a prescribed angle, extracts an unextracted surface as a continuous surface if an angle between the continuous surface and the unextracted surface is within the a prescribed angle with respect to the extracted continuous surface, arranges all continuous surfaces as an inner surface group constituting inner surfaces of the hole shape after extracting all of the continuous surfaces, and eliminates three-dimensional shape data corresponding to the prepared inner surface group from initial three-dimensional shape data. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an operation trajectory creation technique (offline teaching technique) of a welding robot that displays three-dimensional shape data of a work stored in a computer on a display screen and teaches an operation trajectory such as a welding line of the robot.

Conventionally, three-dimensional shape data (three-dimensional CAD data) input to a computer is displayed on a display screen, a welding line to be welded is designated from graphic data constituting a workpiece, and a robot trajectory is created. An off-line teaching system that teaches a desired welding operation is used to teach the robot.
In recent years, three-dimensional shape data (three-dimensional CAD data) created by CAD tends to become more precise due to improvements in computer processing capacity and increase in usable memory. In the off-line teaching of a robot that performs a welding operation, the workpiece graphic displayed on the display screen includes a number of hole shapes into which bolts, screws, and the like that are completely unrelated to the welding operation are inserted. As the size of the three-dimensional shape data increases in this way, when off-line teaching is performed using the three-dimensional shape data, the graphic drawing speed, the coordinate conversion calculation speed during simulation, and the collision detection calculation speed due to interference check are reduced. Performance has declined and it has become difficult to operate efficiently.

  By the way, since the three-dimensional shape data is converted into a general-purpose data format and then taken into the offline teaching system, parameters such as hole information associated with the CAD data are eliminated, and the three-dimensional shape data is composed of minute polygonal surfaces. Consists of multiple surfaces. Therefore, when it is desired to delete a hole shape that is not related to the welding operation, it is necessary to select and delete a plurality of surfaces constituting the hole shape without excess or deficiency so as not to cause inconsistency as a three-dimensional CAD model. There is. Since such a deletion operation has a large number of polygonal surfaces constituting a hole shape, it is time consuming and impractical for an operator to specify the entire surface.

By the way, some techniques for simplifying the shape of the three-dimensional shape data and reducing the data amount have been developed (the following Patent Documents 1 and 2).
Patent Document 1 extracts a 3D shape part using a GUI unit that accepts designation of a three-dimensional (3D) shape part to be displayed and designation of a shape parameter related to the 3D shape, and a shape parameter accepted by the GUI part as a threshold value. Accepts the specification of the shape extraction unit and the removal of the 3D shape part extracted by the shape extraction unit, and accepts the non-removal specification of the 3D shape part received by the GUI unit, and removes it according to the received specification. A shape simplification device including a shape removal unit that performs non-removal processing is disclosed.

  Patent Document 2 uses a storage unit that stores three-dimensional shape data, an input unit, a display unit, and a control unit that displays a three-dimensional shape model on the display unit using the three-dimensional shape data. The appearance of the part is composed of a combination of multiple group surfaces made up of multiple unit surfaces, and a group surface including the surfaces forming the appearance of the 3D shape model is selected based on operations from the input means And a deletion step for deleting the group plane not selected in the appearance selection step based on the operation from the input means, and a three-dimensional shape model after the deletion step based on the operation from the input means. A storage step of storing reduced 3D shape data for display in a storage means is disclosed.

  In particular, a process of selecting a group surface including a surface that is irradiated with virtual plane light from a displayed viewpoint position on a three-dimensional shape model from a plurality of viewpoint positions is displayed. A technical feature is to select a group surface including a surface forming an appearance from the three-dimensional shape model.

JP 2006-072855 A JP 2006-330927 A

However, the technique of Patent Document 1 is suitable for creating an illustration using three-dimensional shape data, and is not applied to welding work, and deletes hole shapes not related to welding work. The technology to do is not disclosed. Therefore, even if it tries to use the data amount reduction technique disclosed in Patent Document 1 when deleting the hole shape, it is difficult to apply the technique.
The technique of Patent Document 2 applies a virtual planar light to a three-dimensional shape model and selects an external surface including a surface on which virtual light has been applied, and a surface on which virtual light is not applied. This technique is difficult to adopt in order to select and delete the inner surface of the hole shape.

  Therefore, in view of the above-described problems, the present invention provides a 3D shape data hole deletion method that can easily and quickly select and delete such a hole shape when the 3D shape data includes a hole shape unrelated to welding. The purpose is to provide. By using the three-dimensional shape data after applying this hole deletion method, it is possible to easily create a work locus and interference check of the welding robot.

In order to achieve the above-described object, the present invention takes the following technical means.
The 3D shape data hole deletion method of the present invention is a 3D shape data hole deletion method for deleting hole shape data from a work figure of 3D shape data displayed on a display screen, If the angle between the “inner surface designating step” for designating the surface constituting the inner side of the hole shape in the workpiece graphic displayed on the surface and the surface designated in the inner surface designating step and the adjacent surface is within a predetermined angle range, The adjacent surface is extracted as a continuous surface, and if the angle between the continuous surface and the unextracted surface adjacent to the extracted continuous surface is within a predetermined angle range, the unextracted surface is Extracting as a continuous surface, extracting all the continuous surfaces, and then collecting all the continuous surfaces as an inner surface group constituting a hole-shaped inner surface; Corresponding to the “hole shape editing step” for adding a continuous surface that could not be extracted in the shape creation step or deleting a predetermined continuous surface from the inner surface group, and the inner surface group created through the hole shape editing step A “hole shape deleting step” for deleting the three-dimensional shape data from the original three-dimensional shape data.

  According to this hole deletion method, when the work of automatically selecting a welding line to be welded by the welding robot is performed based on the work figure of the three-dimensional shape data displayed on the display screen, When deleting hole shape data from the dimension shape data, specify the surface that forms the inside of the hole shape displayed on the display screen, and if the angle between the surface and the adjacent surface is within a certain angle range Extracting as a continuous surface, and extracting the surfaces that are not extracted within the range where the angle between the extracted surface and the adjacent surface is within a certain angle range. You can make an inner group that constitutes.

In addition, it is possible to edit the inner surface group by adding or deleting individual surfaces as necessary. It is necessary to designate each of the polygon figures constituting the hole shape one by one by deleting the inner group (surface, line and point data constituting the group) thus obtained from the original three-dimensional shape data. The hole shape data can be deleted easily and in a short time.
By using the “three-dimensional shape data from which the hole shape data has been deleted” obtained through such work, it is possible to perform interference check and offline teaching of the welding robot with high performance.

  Further, the 3D shape data hole deleting method of the present invention is a 3D shape data hole deleting method for deleting hole shape data from a work figure of 3D shape data displayed on a display screen, wherein the display The “graphic designating step” for designating the work graphic displayed on the screen, the angle between one surface constituting the work graphic designated in the graphic designating step and the surface adjacent to this one surface is predetermined. If the angle is within the range, the adjacent surface is extracted as a continuous surface, and the angle between the continuous surface and the unextracted surface adjacent to the extracted continuous surface is within a predetermined angle range. For example, after extracting the unextracted surface as a continuous surface and extracting all the continuous surfaces, a “continuous surface creation step” for collecting all the continuous surfaces as a surface group, and one hole for the surface group. The inside of The "hole shape creation step" that combines all continuous surfaces into one inner surface group, and the continuous surface that cannot be extracted in the hole shape creation step is added to the inner surface group created by the hole shape creation step Or, “a hole shape editing step” for deleting a predetermined continuous surface from the inner surface group, and three-dimensional shape data corresponding to the inner surface group created through the continuous surface editing step is deleted from the original three-dimensional shape data “ A hole shape deleting step ”.

According to this hole shape deletion method, for a work figure having a plurality of hole shapes, only the work figure displayed on the display screen is designated, and the surface of the designated figure data is sequentially If the angle between the adjacent surfaces is within a certain angle range, it is extracted as a continuous surface. Similarly, the angle between the adjacent surface and the adjacent surface is within the certain angle range. By extracting the non-extracted surfaces one after another, a continuous surface group constituting a continuous surface can be extracted.
Thereafter, it is possible to determine whether or not the extracted continuous surface group is an inner surface group constituting the hole shape, and perform editing to add or delete surfaces individually as necessary. It is necessary to designate each of the polygon figures constituting the hole shape one by one by deleting the inner group (surface, line and point data constituting the group) thus obtained from the original three-dimensional shape data. The hole shape data can be deleted easily and in a short time.

By using the “three-dimensional shape data from which the hole shape data has been deleted” obtained through such work, it is possible to perform interference check and offline teaching of the welding robot with high performance.
Preferably, in the hole shape creation step, all the continuous surfaces constituting the inner surface of one hole are defined as one inner surface group by using a normal vector in each surface of the surface group extracted by the continuous surface creation step. It is good to put together.
Furthermore, an “inner surface integration step” of integrating at least two of the plurality of inner surface groups created in the hole shape editing step as one inner surface group, an inner surface group formed by the hole shape editing step, or the It is preferable to include a “target specifying step” that enables specification of whether or not the inner surface group integrated by the inner surface integration step is the target of the hole shape deletion step.

  By doing so, it becomes possible to reliably specify the hole shape data to be deleted.

  By using the three-dimensional shape data hole deletion method of the present invention, when a hole shape irrelevant to welding is included in the three-dimensional shape data, the three-dimensional shape data can be selected and deleted easily and quickly. An object of the present invention is to provide a method for removing holes. By using the three-dimensional shape data after applying this hole deletion method, it is possible to easily create a work locus and interference check of the welding robot.

1 is an overall configuration diagram of a robot system according to a first embodiment. It is the flowchart which showed the procedure of deletion of the hole shape data which concerns on 1st Embodiment. It is a figure which shows an example of the workpiece | work used as welding object. It is a figure which shows the state which extracted the deletion object (hole shape data) in the workpiece | work of FIG. It is a figure which shows the state which deleted the hole shape data in the workpiece | work of FIG. It is sectional drawing which shows the example of the hole shape made into deletion object. It is a figure for demonstrating the angle which an adjacent surface comprises. It is the flowchart which showed the procedure of deletion of the hole shape data which concerns on 2nd Embodiment. It is a figure for demonstrating the procedure which recognizes whether it is the surface (inner surface) which comprises a hole shape. It is a figure which shows the example of application to the workpiece | work provided with many holes. It is a figure which shows the deletion result in FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.
Furthermore, in the following, a vertical articulated 6-axis welding robot will be described. However, the present invention is not limited to a robot having such a type, number of axes, and application.
[First Embodiment]
With reference to FIG. 1, the overall configuration of the robot system according to the first embodiment of the present invention will be described.

As shown in FIG. 1, a robot system 1 includes a welding robot 2 having vertical articulated six axes, a control device 4 having a teaching pendant 3, and a personal computer 5 (hereinafter referred to as a personal computer). Including. Further, a slider for moving the welding robot itself and a positioner for gripping the workpiece W in a state where the posture can be changed may be provided.
The welding robot 2 is provided with a welding torch 6 as a processing tool. The control device 4 includes an arithmetic device and controls the welding robot 2 according to a program that teaches the operation of the welding robot 2 in advance. The teaching program may be created using the teaching pendant 3 connected to the control device 4 or may be created using an offline teaching system using the personal computer 5.

In any case, the teaching program is created in advance before the actual operation. The program created by the personal computer 5 is delivered to the control device 4 via a medium or the like that magnetically stores data, or transferred to the control device 4 by data communication.
The personal computer 5, that is, the off-life teaching system includes a display (CRT) that can display graphics as a display device, and includes a keyboard or a mouse as an input device. In addition, a magnetic storage device or a communication device is provided in order to capture CAD information of the workpiece W.

  In the off-line teaching system, CAD information of the workpiece W is converted into a predetermined data format and graphic data is taken in. The taken-in work shape is rotated and moved to a predetermined position with respect to the welding robot 2 and installed at a position where the actual work W is attached. Teaching data is created while looking at the graphic screen on the personal computer 5 with respect to the positional relationship arranged with respect to the welding robot 2. In this way, in the process of creating teaching data, a welding check operation is frequently performed by performing a simulation operation for interference check or operation check, or changing the viewpoint of the graphic screen.

  Regarding the three-dimensional shape data of the workpiece W taken in, it includes information other than the shape for defining the welding operation, for example, shape data such as a hole into which a bolt is inserted. There is no direct relationship. When there are many pieces of shape data irrelevant to such welding work, calculation time such as interference check, operation simulation, and viewpoint operation performed in the course of teaching work becomes long, and work efficiency deteriorates. Therefore, when the three-dimensional shape data (three-dimensional CAD data) of the workpiece W is captured, the processing described below is performed to delete unnecessary data in advance, thereby improving the operation efficiency of the subsequent teaching work. This is a feature of the robot system 1 according to the present embodiment.

With reference to FIG. 2, a method for deleting a hole in the three-dimensional shape data according to the present embodiment will be described. This process is executed by the off-line teaching system, that is, the personal computer 5.
First, in S100 which is an inner surface designation step, the operator selects a surface having a hole shape on the CRT of the personal computer 5, that is, an inner surface to be deleted.
Next, in S110, which is a hole shape creation step, continuous faces (polygon faces) are extracted from the selected inner face and grouped as an inner face group.
In S120, which is the hole shape editing step, the inner surface that is not deleted or the surface that is to be added as a deletion target is edited for the inner surface group as necessary. This process is performed on the CRT by the operator.

In S130, it is determined whether there is another hole shape to be deleted. If there is another hole shape to be deleted (YES in S130), the process returns to S100 and S100 to S120 are repeated. If not (NO in S130), the process proceeds to S140.
In S140, which is a hole shape deletion step, the graphic information (hole shape data) of the extracted inner surface group is deleted from the original three-dimensional shape data.
Detailed operation of each step will be described below.
First, the operator who views the graphic screen displayed on the CRT of the personal computer 5 clicks one of the inner surfaces constituting the hole to be deleted with the mouse (S100).

With respect to the inner surface selected by the mouse, the personal computer 5 automatically extracts adjacent surfaces which can be regarded as continuous surfaces one after another, and manages them as a group as a group (S110). At this time, a surface within a predetermined angle range (for example, an angle as shown in FIG. 7 within a range of θ = 180 ° ± 40 °) is automatically extracted as a continuous surface. Note that this angle range changes depending on the precision of the converted graphic data, so that the operator can set it as necessary.
Further, the operator adds the inner surface that could not be extracted (the inner surface forming the hole shape) to the extracted inner surface group (S120). As the “inner surface to be deleted” that could not be extracted, for example, in the case of a hole with a step as shown in FIG. 6B, a step surface (indicated by a thick line), a non-through hole as shown in FIG. In this case, the bottom surface (indicated by a thick line) corresponds. The counterbore surface of the hole (shown by a thick line) as shown in FIG. 6C and the sloped bottom surface of the non-through hole (shown by a thick line) as shown in FIG. There is a possibility.

At this time, it is also possible to automatically extract continuous surfaces from the inner surface to be added and add a plurality of surfaces. The hole shape shown in FIG. 3 is the chamfered hole shape shown in FIG. 6C, and the inner surface group to be deleted is set by adding a counterbore surface to the inner surface group.
Furthermore, if necessary (YES in S130), another hole-shaped inner surface group is set (S100 to S120). FIG. 4 shows a state in which the operations of steps S100 to S120 are performed three times for each of the three hole shapes.
After that, even if the set inner surface group is deleted, it is confirmed whether or not there is a contradiction in the original three-dimensional shape data, and the hole shape data to be deleted (surface, line and point data constituting it) ) Is deleted from the original three-dimensional shape data. (S140).

In this way, the hole shape shown in FIG. 3 can be obtained by performing the click operation of the surface with the mouse a plurality of times (once or three times). Can be easily removed.
[Second Embodiment]
Hereinafter, a second embodiment of the present invention will be described.
In the first embodiment described above, when there are a plurality of hole shapes in the target graphic, it is necessary to perform an operation of designating the inner surface one by one, but a huge number (for example, several hundreds) For the three-dimensional shape data having a hole shape, the work becomes complicated and the work time increases. Therefore, in the present embodiment, a technique is disclosed in which hole shape data can be selected in a lump and can be deleted.

The robot system in the present embodiment is also the same as the robot system in the first embodiment, and the processing content (program control structure) shown below is different.
With reference to FIG. 8, a method for deleting holes in the three-dimensional shape data according to the present embodiment will be described. This processing is also realized in the form of a program on the personal computer 5 and is executed by the personal computer 5.
First, in S200, which is a graphic designating step, the operator selects a member (work graphic) having a hole shape on the CRT of the personal computer 5. The work figure here is, for example, a horizontally long rectangular member indicated by A in FIG.

Next, in S210, it is determined whether or not the extraction work of the inner surface group constituting the hole shape described later has been completed for all the planes constituting the selected work graphic (whether the investigation has been completed). . When the survey is completed for all planes of the selected graphic model (YES in S210), the process proceeds to S240. If not (NO in S210), the process proceeds to S220.
In S220 which is a continuous surface creation step, it is determined whether or not a continuous surface can be extracted from the surface of the selected work figure. If a continuous surface can be extracted for the surface of the selected graphic model (YES in S220), the process proceeds to S230. If not (NO in S220), the process returns to S210.

In S240, which is the hole shape creation step, only the inner surface group constituting the hole shape is selected from the extracted continuous surface group. In other words, all the continuous surfaces constituting the inner surface of one hole are collected as one inner surface group.
In S250, the selected inner surface group is displayed as a list and displayed on the CRT.
In S260, which is the hole shape editing step, the inner surface that is not deleted or the surface that is to be added as a deletion target is edited for the inner surface group as necessary. This process is performed on the CRT by the operator. Furthermore, in S260, a certain inner surface group and other groups are integrated (inner surface integration step), and it is determined whether or not the extracted inner surface group is to be deleted (target specifying step).

In S270, which is a hole shape deletion step, the information on the inner surface group (hole shape data) that is the object of deletion is deleted from the original three-dimensional shape data.
Detailed operation of each step will be described below.
First, an operator who sees the graphic displayed on the CRT selects a work figure (target member) having a hole to be deleted with the mouse (S200).
Then, the personal computer 5 extracts, as all the continuous surfaces, the surfaces whose adjacent surfaces are within the set angle range with respect to all the surfaces of the selected work graphic A (S220, S230). For example, a surface whose angle is in the range of θ = 180 ° ± 40 ° as shown in FIG. 7 is automatically extracted as a continuous surface. Next, as shown in FIG. On the other hand, it is determined whether or not the group forms a hole shape. As a determination method, for example, a normal vector is set for all the extracted surfaces, and a group of surfaces in which the normal vectors intersect with each other at approximately one point (the normal vector faces inward) is defined as an inner surface group. This inner surface group shall constitute the inner surface of the hole. (S240).

After that, the extracted inner surface group is displayed as a list on the CRT and the selected surface is displayed graphically (S250).
For the displayed inner surface group, addition or deletion of other planes or integration of other inner surface groups is performed as necessary. In addition, for the inner surface group that is not a deletion target, a setting not to be processed is performed so that unnecessary deletion processing is not performed (S260).
After that, even if the set inner surface group is deleted, it is confirmed whether or not there is a contradiction in the original three-dimensional shape data, and the hole shape data to be deleted (surface, line and point data constituting it) ) Is deleted from the original three-dimensional shape data. (S270).

Thereby, unnecessary figure data can be deleted with a simple operation on a work figure having a plurality of hole shapes.
FIG. 10 shows the result of performing the hole shape deletion processing according to the present embodiment on the graphic data (FIG. 10A) having about 10 hole shapes. As shown in FIG. 10B, it can be seen that the hole shape is surely deleted after the processing.
Before and after applying this hole shape deletion method, as shown in FIG. 11, the number of elements of points, lines, and faces is reduced by 80% or more with respect to the original graphic data, thereby converting the coordinates of each vertex. The number of operations, the number of surfaces to be drawn, and the number of vertices, lines, and surfaces for performing interference check operations are reduced, and a dramatic effect is obtained.

The present invention is not limited to the above-described embodiments, and various modifications can be made. For example, although the embodiment has been described by taking an offline teaching system for a welding robot as an example, the application of the present invention can also be applied to various CAM systems where the hole shape does not affect the target work, such as an offline teaching system for a painting robot. .
It should be thought that embodiment disclosed this time is an illustration and restrictive at no points. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 1 Robot system 2 Welding robot 3 Teaching pendant 4 Control apparatus 5 Personal computer 6 Welding torch

Claims (4)

A 3D shape data hole deletion method for deleting hole shape data from a 3D shape data work figure displayed on a display screen,
"Inner surface designation step" for designating a surface constituting the inside of the hole shape in the work graphic displayed on the display screen,
If the angle between the surface designated in the inner surface designation step and the adjacent surface is within a predetermined angle range, the adjacent surface is extracted as a continuous surface, and the continuous surface is extracted from the continuous surface. If the angle with the adjacent unextracted surface is within a predetermined angle range, the unextracted surface is extracted as a continuous surface, all the continuous surfaces are extracted, and then all the continuous surfaces are formed as hole-shaped inner surfaces. `` Hole shape creation step '' to collect as an inner group that constitutes
For the inner surface group, add a continuous surface that could not be extracted in the hole shape creation step, or delete a predetermined continuous surface from the inner surface group, "hole shape editing step",
“Hole shape deletion step” for deleting the three-dimensional shape data corresponding to the inner surface group created through the hole shape editing step from the original three-dimensional shape data;
A method for deleting holes in three-dimensional shape data. A 3D shape data hole deletion method for deleting hole shape data from a 3D shape data work figure displayed on a display screen,
“Graphic designating step” for designating a work graphic displayed on the display screen;
If the angle between one surface constituting the work graphic specified in the graphic specifying step and the surface adjacent to the one surface is within a predetermined angle range, the adjacent surface is extracted as a continuous surface. If the angle between the extracted continuous surface and the unextracted surface adjacent to the continuous surface is within a predetermined angle range, the unextracted surface is extracted as a continuous surface, and all the continuous surfaces are extracted. After extracting the `` continuous surface creation step '' that summarizes all the continuous surfaces as a surface group,
“Hole shape creation step” in which all continuous surfaces constituting the inner surface of one hole are grouped as one inner surface group with respect to the surface group;
To the inner surface group created by the hole shape creation step, add a continuous surface that could not be extracted in the hole shape creation step, or delete a predetermined continuous surface from the inner surface group, "hole shape editing step",
3. Hole deletion of 3D shape data, comprising: a “hole shape deletion step” for deleting 3D shape data corresponding to the inner surface group created through the continuous surface editing step from the original 3D shape data Method.   In the hole shape creation step, all the continuous surfaces constituting the inner surface of one hole are grouped as one inner surface group using the normal vector in each surface of the surface group extracted by the continuous surface creation step. The hole deletion method for three-dimensional shape data according to claim 2. An “inner surface integration step” of integrating at least two or more of the plurality of inner surface groups created in the hole shape editing step as one inner surface group;
`` Target designation step '' that allows designation of whether or not the inner surface group formed by the hole shape editing step or the inner surface group integrated by the inner surface integration step is the target of the hole shape deletion step,
The hole deletion method for three-dimensional shape data according to claim 2 or 3, characterized by comprising: