JP5346674B2 - Marking control system and method for aligning members marked using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a marking control system that properly aligns two members by marking at any position or angle, even in pattern matching by a camera from any position, and to provide a method of aligning the members marked by the same. <P>SOLUTION: The marking control system 1 equipped in a marking machine for putting marks on first and second members includes: a plane derivation processing part 8 acquiring information from an assembly plan database 2 and a camera database 3 storing camera information, and deriving a camera plane image seen from the camera; and a mark deformation processing part 9 for deforming the mark to a shape that can be pattern-matched by the camera, from a marking database 4 storing marking position information and a mark database 5 storing a shape of the mark. Deformation mark conversion information is transmitted to a marking means equipped in the marking machine 7. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a marking control system that can mark a member (particularly, a plate material) with a mark that can be easily pattern-matched by a camera, and a method for aligning members marked using the marking control system.

  Patent Literature 1 discloses a positioning device that adjusts the relative positional relationship between two objects using a monitor image of one image input device. In this method, the positions on the monitor screen of positioning marks previously marked on two objects are detected, and the objects are positioned and moved so that the respective mark positions or relative positions satisfy a predetermined condition. In the positioning device of Patent Literature 1, the positions of the linear marks attached to both members (objects) are aligned so that they are aligned in a straight line. As described above, as a method of aligning positions using marks, as disclosed in Patent Document 2 and Patent Document 3, methods of overlapping or arranging circular marks are disclosed.

  Such alignment by marks is performed by pattern matching using image recognition by a camera. However, Patent Documents 1 to 3 do not consider how the mark is recognized when viewed from the camera when recognizing the image of the mark. For example, when the members to be aligned are joined at an angle, when marks attached to them are viewed from the same camera position, the marks may appear different depending on the angle. Therefore, even if the same mark is given to the two members, it may be recognized as a different mark by pattern matching, and alignment may not be performed normally.

Japanese Patent Laid-Open No. 7-72930 Japanese Patent Laid-Open No. 10-272758 JP 2004-4373 A

  The present invention takes the above-mentioned prior art into consideration, and in the case of aligning two members by marking, the camera can be used from any position to align both members at any position and angle. An object of the present invention is to provide a marking control system capable of accurately aligning positions with each other even when pattern matching is performed, and a method for aligning members marked using the marking control system.

In order to achieve the above object, according to the first aspect of the present invention, the first and second marks serving as indices for aligning the positions of the first member and the second member assembled with each other are provided. A marking control system for a marking machine attached to each of the members, wherein the assembly plan database stores mutual position and angle information after alignment of the first member and the second member, and The position and angle information of the camera with respect to the first and second members is stored in order to pattern-match the image of the mark imaged by the same camera at the time of alignment of the first and second members by image processing. Each information obtained from the camera database, the assembly plan database, and the camera database, and the first member after alignment and A plane derivation processing unit for deriving a camera plane image when the two members are viewed from the camera, and a marking in which marking position information which is a position to attach the mark in the first member and the second member is stored A database; a mark database in which the shape of the mark is stored; and the marking position information is obtained from the marking database; the mark shape is selected from the mark database; and the mark shape is displayed on the camera plane image. A mark deformation processing unit for deforming into a deformable mark that can be pattern-matched, and the mark deformation processing unit includes the mark attached to the first and second members by the marking machine on the camera plane image. In the marking means of the marking machine to be projected as a mark (before deformation) Providing a marking control system characterized by transmitting the image command.

  According to a second aspect of the present invention, there is provided a method for aligning the marked members using the marking control system according to the first aspect, wherein the first and second members are abutted, and then the camera From each deformation mark (projected as a mark before deformation on the camera plane image) applied to the marking surfaces of the first and second members on the planar image, toward the intersection of the marking surfaces An auxiliary line is drawn, a first intersection where the auxiliary line from the deformation mark of the first member intersects the intersecting line, and an auxiliary line from the deformation mark of the second member intersects the second intersecting line Provided is a method for aligning members marked using a marking control system, wherein the first member and the second member are aligned based on a positional relationship with an intersection.

  According to a third aspect of the present invention, in the second aspect of the present invention, the deformation mark is a line-drawn figure having a reference side extending in a direction perpendicularly intersecting at least the intersection line, while the auxiliary line has the reference side. It is a straight line extending to the intersection line, and when the distance from the first and second intersection points is less than an allowable value, it is determined that the positions of the first and second members are aligned. Yes.

  According to the invention of claim 1, the position and angle of each of the first member and the second member after alignment are obtained from the assembly plan database, and the position and angle of the camera used for pattern matching are obtained from the camera database. It is possible to obtain the camera plane image when the first member and the second member are viewed from the camera by the plane derivation processing unit. Further, the marking positions for the first member and the second member are respectively obtained from the marking database, the mark to be added this time is selected from the mark database, and the mark is derived when the mark is attached to the acquired marking position. In order to determine what shape is recognized in the camera plane image, a deformation mark is created by the mark deformation processing unit, and this is transmitted to the marking means provided in the marking machine so as to be attached to the marking position. Therefore, since the deformation mark that can be surely pattern-matched by the camera is attached to the member in advance for positioning, both members can be quickly and accurately positioned without erroneously recognizing the mark. Further, if the camera position is the same, the derived camera plane image can be used repeatedly, so that the mark can be quickly deformed and the workability is improved.

According to the invention of claim 2, from the deformation marks attached to the first and second members, the auxiliary lines are drawn toward the intersecting lines, respectively, and based on the positional relationship between these first and second intersecting points, Since the first and second members are aligned, it is possible to efficiently align both members by a simple method.
According to the invention of claim 3, the deformed mark having the reference side perpendicularly intersecting the line of intersection on the marking surface with the first and second members coincides with the auxiliary line obtained by extending the reference side. As described above, since the first and second members are marked, it is possible to ensure the alignment of both members by confirming that the intersecting points where the auxiliary line and the intersecting line intersect each other coincide. . Furthermore, since it is possible to determine the alignment by setting the distance between the two intersections to be equal to or less than the allowable value, it is possible to perform the alignment of both members with an accuracy corresponding to the member to be aligned.

1 is a schematic block diagram of a marking control system according to the present invention. It is explanatory drawing of a camera plane and a member plane. It is explanatory drawing of the positioning method of the members marked using the marking control system which concerns on this invention. It is a flowchart of the positioning method of the members marked using the marking control system which concerns on this invention.

FIG. 1 is a schematic block diagram of a marking control system according to the present invention, and FIG. 2 is an explanatory diagram of a camera plane and a member plane.
The marking control system 1 according to the present invention includes an assembly plan database 2, a camera database 3, a marking database 4, a mark database 5, and a mark deformation module 6. The marking control system 1 acquires each information from each of the databases 2, 3, 4, and 5 and processes them by the mark deformation module 6 to create a deformation mark and attach the mark together with the drawing position information on the member It is transmitted to the marking machine (means) 7.

  The assembly plan database 2 stores information such as assembly positions and assembly angles of assembly members. For example, it is information on what position and angle the second member contacts the first member with respect to the first member to be assembled. The camera database 3 stores information on the position and orientation (angle) of the camera for pattern matching. For example, in the scene where the first member and the second member are actually assembled, the information indicates from which position and angle the camera is visually recognized when aligning the two members.

The marking database 4 stores positioning mark drawing position information on the assembly member. For example, information such as which part (position) of the first member and the second member is to be marked. The mark database 5 stores a mark-shaped pattern when the (positioning) mark faces the camera.
The mark deformation module 6 includes a plane derivation block 8 and a plane conversion block 9. The plane derivation block 8 acquires the assembly position / angle of the first member and the second member, as well as the position / angle information of the camera from the assembly plan database 2 and the camera database 3, and assembles from the camera position / angle. A camera plane image when the member is photographed is obtained by calculation. That is, as shown in FIG. 2, the actual member plane Q is recognized as the camera plane q based on the position and angle of the camera. A camera plane q with respect to the member plane Q is obtained by calculation.

  The derivation of the camera plane image can use homography conversion, which is a method of projecting from one plane in the three-dimensional space to another plane. This homography transformation is a method of transforming a point Q (X, Y, Z) in a three-dimensional space into a plane q (x, y) using a 3 × 3 homography matrix. As a result, it is possible to determine how the mark attached to the actual member plane is deformed and recognized by the camera.

  The plane conversion block 9 acquires information of the camera plane image derived by the plane deriving block 8 and information from the marking database 4 and the mark database 5. By combining these pieces of information, how an arbitrary mark selected from the mark database 5 is added to a predetermined location of the first and second members based on the assembly plan database 2 is reflected in the camera plane image. Ask for. That is, a deformed mark in which an arbitrary mark selected from the mark database 5 is recognized by the camera plane image is obtained.

  The deformation mark is subjected to, for example, the reverse conversion of the above-described conversion from Q to q so that the deformation mark can be recognized in the camera plane image, that is, the points q1 and q2 in the camera plane image are members. It is converted into Q1 and Q2 on the plane. The deformation mark conversion information is transmitted to the marking machine 7 as a drawing command of a drawing position on the member and its mark pattern information. Then, the marking member (not shown) provided in the marking machine 7 marks the first member and the second member in such a manner that the deformation mark can be pattern-matched with the camera plane image.

  As described above, since the deformation marks that can be surely pattern-matched by the camera are attached to the members in advance for positioning, both members can be quickly and accurately positioned without erroneously recognizing the marks. Further, if the camera position is the same, the derived camera plane image can be used repeatedly, so that the mark can be quickly deformed and the workability is improved.

FIG. 3 is an explanatory diagram of a method for aligning members marked using the marking control system according to the present invention.
As shown in the figure, in this example, a configuration in which the second member 11 is vertically assembled on the first member 10 is recognized by a camera plane image. A deformation mark 12 is marked on each of the first and second members 10 and 11. When the camera that performs pattern matching recognizes the deformation mark 12 and determines that it is the same figure, it then aligns both members 10 and 11 based on the deformation mark 12.

Note that the figures (marks) for pattern matching are not limited to the same figure, and various figures (for example, arrows) can be used even if they are not right triangles as shown. Such pattern matching can be performed by setting correspondence of image recognition by the camera in advance.
When the deformation mark is a right triangle as shown in the figure, when the right triangle is marked to face the member, a right triangle 12a indicated by a dotted line in the figure is obtained. When this is recognized by a camera plane image (when viewed from the angle shown), both marks are distorted and cannot be recognized as the same mark. Therefore, in order to perform pattern matching, a deformation mark is obtained so as to be the same mark in the camera plane image, and both members are marked in advance.

  If the mark is simple (for example, a straight line), it may be erroneously recognized as a joint between members, an edge of the member, a shadow, or the like. In order to automatically detect a mark by a camera, a method is used in which a mark pattern registered in advance and an image on the screen are matched, and a matching degree is extracted to a predetermined value or more. Specifically, there are a normalized correlation method that performs pattern matching of the entire region including the mark, a method that performs pattern matching of the contour shape of a mark obtained by extracting a light and shade contour from an image, and the like.

  For alignment of both the members 10 and 11, an auxiliary line 14 (broken line in the drawing) is drawn from the deformation mark 12 toward the intersection line 13 on the marking surface of both the members 10 and 11. For example, when the deformation mark 12 as shown is a right triangle and an extension line of one side (reference side B) intersects the intersection line 13 perpendicularly, the extension line is set as an auxiliary line 14. That is, the reference side B is formed perpendicular to the intersection line 13. The points where the auxiliary line 14 intersects the intersection line 13 are defined as the intersection points 10a and 11a. When the distance between these intersection points is equal to or less than the allowable value, it is determined that both the members 10 and 11 are in alignment. Therefore, in such a case, the first and second members are marked in advance so that the intersections 10a and 11a coincide. Note that the method of drawing the auxiliary line 14 and the determination criteria based on the intersections 10a and 11a are not limited to this.

FIG. 4 is a flowchart of a method for aligning members marked using the marking control system according to the present invention.
Step S1:
The first member and the second member are transported by a robot arm or the like to the work table for alignment, and are placed in contact with each other at the assembly position. The deformation mark in the camera plane image is detected by a camera for pattern matching of the placed first member and second member. This deformation mark is marked on both members in advance.

Step S2:
An auxiliary line is drawn from the deformation mark to the intersection line on the marking surface of both members. Further, the position of the intersection of the auxiliary line and the intersection line is calculated. The deformation mark is marked on the first member and the second member in advance at different locations in consideration of how to draw the auxiliary line so that the intersections coincide with each other. An example of how to draw the auxiliary line is as shown in FIG.

Step S3:
It is determined whether the distance between the intersections is less than the allowable value.
Step S4:
When the distance between the intersections is larger than the allowable value, one or both of the members are moved so that the intersections approach each other (so that the distance between the intersections is equal to or less than the allowable value). After the movement, the process returns to step S1.

Step S5:
If the distance between the intersections is less than or equal to the allowable value in step S3, it is determined that the alignment of both members has been completed, and temporary welding is performed. After that, in order to carry out formal welding, it is conveyed while being temporarily welded to a predetermined place.
As described above, the deformation mark having a reference side perpendicularly intersecting the intersection line on the marking surface with the first and second members is aligned with the auxiliary line extending the reference side so that the intersection line coincides with the auxiliary line. Since the first and second members are marked, it is possible to ensure the alignment of both members by confirming that the intersections of the auxiliary lines and the intersecting lines coincide with each other. Furthermore, since it is possible to determine the alignment by setting the distance between the two intersections to be equal to or less than the allowable value, it is possible to perform the alignment of both members with an accuracy corresponding to the member to be aligned.

1 Marking Control System 2 Assembly Plan Database 3 Camera Database 4 Marking Database 5 Mark Database 6 Mark Deformation Module 7 Marking Machine 8 Plane Derivation Block 9 Plane Conversion Block 10 First Member 11 Second Member 12 Deformation Mark 13 Crossing Line 14 Auxiliary line

Claims (3)

A marking control system for a marking machine that marks each of the first and second members with a mark serving as an index for aligning the position between the first member and the second member assembled to each other Because
An assembly plan database storing mutual position and angle information after the alignment of the first member and the second member;
The position and angle information of the camera with respect to the first and second members is stored in order to perform pattern matching on the image of the mark captured by the same camera when the first and second members are aligned. Camera database,
A plane derivation processing unit for obtaining respective information from the assembly plan database and the camera database and deriving a camera plane image when the first member and the second member after alignment are viewed from the camera;
A marking database storing marking position information, which is a position to attach the mark in the first member and the second member;
A mark database storing the shape of the mark;
A mark deformation processing unit for acquiring the marking position information from the marking database, selecting the shape of the mark from the mark database, and transforming the shape of the mark into a deformable mark that can be pattern-matched on the camera plane image; Have
The mark deformation processing unit is arranged on the marking unit of the marking machine so that the mark attached to the first and second members by the marking machine is displayed as the mark (before deformation) on the camera plane image. A marking control system characterized by transmitting a drawing command. Using the marking control system according to claim 1, a method for aligning marked members,
After the first and second members are brought into contact with each other, the respective markings applied to the marking surfaces of the first and second members on the camera plane image (projected as untransformed marks on the camera plane image). An auxiliary line is drawn from the deformation mark toward the intersection line of the marking surface, the first intersection point where the auxiliary line from the deformation mark of the first member intersects the intersection line, and the second member Using a marking control system, wherein the first member and the second member are aligned based on a positional relationship between an auxiliary line from a deformation mark and a second intersection where the intersection line intersects. Positioning method for marked members.   The deformation mark is a line drawing figure having a reference side extending in a direction perpendicular to at least the intersection line, while the auxiliary line is a straight line extending the reference side to the intersection line, The marking using the marking control system according to claim 2, wherein when the distance to the second intersection is equal to or less than an allowable value, it is determined that the positions of the first and second members are aligned. Method for aligning the formed members.

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