JP2001124520A - Structural element provided with marker optically recognizable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a marker not to have anything to do with production technique, illumination technique and material quality. SOLUTION: A structural element 2 comprises at least one marker 1, which an optical image processing system is capable of recognizing. At least one marker 1 has at least one edge 3, and the edge is either inclined 8, bent 13 or flattened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a structural element provided with an optically recognizable marker and a method for recognizing a marker or a mounting position of an element by the marker. How to decide.

[0002]

BACKGROUND OF THE INVENTION When it is necessary to mount electronic chips or elements on structural elements very precisely, an image processing system is used, which is controlled by optical illumination techniques, observation cameras and evaluation calculators. The mounting position can be examined and the positioning system can control the elements to be mounted. Recognition of the mounting position is effected, in large part, by the production-induced, unfavorable rounding of the edge of the electronic chip mounting position. These rounded areas appear darker in the viewing camera due to the bright field illumination in the coaxial light of the illumination source and provide an appreciable contrast to the brighter appearing flat areas.

A disadvantage arises when these roundings are formed very weakly and there is not enough contrast between the roundness and the area surrounding the roundness. This may result in incorrect or no recognition of the position of the edge, or the roundness may change due to fabrication, changing the contrast and placing the element at various locations. For example, the roundness caused by punching-in depends on the sharpness of the production tool and changes over time. It is possible to adapt the image processing system to continuous changes in roundness. However, a problem arises when using multiple production systems due to the different roundness of the structural elements produced by different production systems at the same time. It is therefore also difficult to adapt the image processing system accordingly.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to make the marker independent of fabrication technology, illumination technology and material quality, so that the image processing system does not need to be adapted to changing conditions. It is to be.

[0005]

According to the invention, this object is achieved by the features according to claim 1 or 10 or 11.

[0006]

According to the invention, the contrast between the marker and its surroundings is very good, whereby the edges of the structural element and thus the mounting position of the element can be determined more accurately and can be reproduced. The time-consuming adaptation of the image processing system is eliminated and the production time is reduced. Accurate positioning improves the function of the electronic chip, for example the deposition characteristics of the sensor chip on the sensor support of the air mass measuring device. Production costs are reduced due to improved quality.

A particular advantage is that simple geometrical changes of the structural element are achieved without adversely affecting the function of the structural element.

[0008]

Advantageous embodiments of the invention are described in the dependent claims.

[0009] It is particularly advantageous to attach the markers during the fabrication process of the structural element so that the contours of the cutouts or ridges are completely understood.

[0010] Furthermore, it is advantageous to provide the marker in the range of the mounting position.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The construction of the present invention will be specifically described below with reference to the embodiments shown in the drawings.

1a to 1g show a plan view and a sectional view of a structural element 2 with various markers.

FIG. 1 a shows a plan view of a structural element 2 with a marker 1 having at least one edge 3. The marker 1 has, for example, a square cross section at the level of the surface 12 of the structural element 2. The cross section at the height of the surface 12 can also be triangular, rectangular or polygonal.

FIGS. 1b and 1c show two different embodiments of the marker 1 in a section along the line AA in FIG. 1a. The marker 1 is, for example, a triangular ridge 6 on the structural element 2 (FIG. 1b) or a triangular recess 7 in the structural element 2 (c in FIG. 1). The ridge 6 or the recess 7 has at least one slope 8. It does not matter on which side the slope 8 is configured. The different orientations of the slope 8 are shown in FIG.
B and c. The edge 3 extends, for example, perpendicular to the surface 12 in FIGS. The raised portion 6 may be formed in a conical shape, for example. Another example of the shape of the marker 1 of the structural element 2 is shown in FIG.

FIG. 1 d shows a plan view of a structural element 2 with a marker 1 having at least one edge 3. The marker 1 has, for example, a semicircular cross section at the level of the surface 12 of the structural element 2. Surface 1
The cross section at the height of 2 can be, for example, semi-elliptical. The marker 1 is shown in FIG.
It can be configured as a ridge 6, as shown in cross section along line -B. However, the markers can also be configured as recesses 7, for example. The marker 1 is here formed by a curved surface 13. The curvature of the curved surface 13 may be convex or concave. In FIG. 1 e, the edge 3 extends, for example, perpendicular to the surface 12.

Another example of the shape of the marker 1 of the structural element 2 is shown in FIG.

FIG. 1 f shows a plan view of the structural element 2 with the marker 1. The marker 1 has, for example, a circular cross section at the level of the surface 12. The cross section at the height of the surface 12 can also be configured, for example, as an ellipse. The marker 1 is shown in FIG.
It is configured as a recess 7 having, for example, a circular cross section, as shown in cross section along the line. This recess 7
Can also have a semi-circular or semi-elliptical cross-section.

FIG. 2 shows how the marker 1 is provided in, for example, a rectangular cutout 15. FIG. 2a shows a plan view of the structural element 2 with a cutout 15 at the level of the surface 12 having, for example, a rectangular shape. The notch has, for example, a rectangular bottom surface 16 separated by the edge 3.
The notch 15 and the bottom surface 16 can have, for example, another, angular and / or circular geometry.

FIG. 2b shows a cross section along the line aa in FIG. 2a with the marker 1 not yet formed directly. The edge 3 extends, for example, perpendicular to the surface 12 and / or the bottom surface 16. Incidentally, in FIG. 2C, the structural element 2 is configured as follows. That is, marker 1 exists, and this marker is
Are formed by post-machining the notched edge 3 of the structural element 2 shown in FIG.

The possible shapes of the marker 1 are shown in FIGS. 2d and e, which are cross-sectional views along the line aa in FIG. 2c.

In FIG. 2d, the edge 3 shown in FIG. 2b is cut obliquely at the height of the surface 12 by the slope 12 towards the notch 15, so that the surface 12 of the notch 15 The cross section at
Is larger than in. Instead of slope 8,
For example, a curved surface 13 that is arbitrarily curved may be provided. The slope 8 or the curved surface 13 can extend from the height of the surface 12 to the height of the bottom surface 16, but this is not necessary as shown in FIG. 2d.

However, the marker 1 can also be provided, for example, by forming a recess 7 in the bottom 16 of the notch 15, as shown in FIG. In this case, the bottom 16
Corresponds to the surface 12 of c or g in FIG. Instead of the recess 7, for example, the ridge 6 may be configured in the range of the edge 3 (FIG. 2 b). The recess 7 or the ridge 6 can be configured as already described in FIG. In particular, the alignment of the slope 8 of the recess 7 is not important.

The slope 8 of the obliquely cut edge 3 of the rectangular cutout 15 in FIG. 2d determines the position and size of the cutout, and thereby the mounting position for an electronic chip or element. Can be determined. However, notch 1
5 the entire contour of the bottom surface 16 or the surface 12 of the notch 15
It is not necessary to know the cross-section at the height of the plane. For example, it is sufficient to determine the positions of two markers that are not facing each other. This is, for example, marker 1 of f in FIG.
7, 18. These markers 17 and 18 are shown in FIG.
Or, it only forms a part of the marker 1 of e.
The marker 1 in FIG. 2C is indicated by a broken line in FIG. 2F. The configuration of the markers 17 and 18 is as described in FIGS.

The markers 17, 18 need not be in contact with each other. This is because if the shape (for example, a rectangle) of the notch 15 is known, the intersection of these two edges can be calculated. Since the size of the notch is known, the other corner vertices of the notch 15 can also be calculated, so that the element is inserted exactly into the notch 15.

The position of the notch 15 for each of the other geometries and sizes known to the image processing system, and for each of the mounting locations within the notch 15 of the electronic chip or element. And how much marker 1 is needed to determine the size and size.

The at least one marker 1 can be provided by an additional recess 7 or ridge 6 or by a structural element 2
Can be produced during the production of the structural element 2 or in an additional step as a chamfer of the at least one existing edge 3.

FIG. 3 shows, as an example of the structural element 2, a sensor support 20 which is part of a device for measuring the mass of a flowing medium, in particular the mass of the intake air of an internal combustion engine. The structure of the sensor support 20 and the air mass measuring device is DE 44 26 10
2 C2 or US-P 5,693,879, which are hereby incorporated by reference.

The sensor support 20 has a sheet metal element 22 with a plastic coating 23 which is connected to a basic support 21. The sensor support 20 has a landing edge 24
have. A sensor cavity 27 having a sensor cavity bottom surface 28 is formed in the sensor support 20. The sensor cavity bottom surface 28 is divided by a passage 35 into a support surface 36 and a sensor base surface 38. The support surface 36 has four edges 42a to 42d, and one edge 42d
Forms an edge to the passage 35. Similarly, sensor base surface 38 has four edges 43a-43d, one edge 43b of which forms an edge to passage 35. A measuring element 46, for example, shown as a dashed chip, is mounted in the sensor cavity 27 along which the medium flows. The manner of attachment will be described later. The sensor cavity 27 has two notches 47, 4
7 ', these cutouts
At the edge of the sensor cavity 27 parallel to 4. The notches 47, 47 'have a bevel 8 which already exists and was not considered as a marker 1 in the construction.

The edges 42a to 42c of the support surface 36 and the edges 43a, 43c, 43d of the sensor base surface 38 are formed with a slope 8 as shown in FIG. These slopes 8
Form a marker 1.

The marker 1 can also be formed by making the edges 42d and 43b inclined at the height of the sensor cavity bottom surface 28 of the passage 35 or the height of the bottom surface of the passage 35. Further, for example, the slope 8 on which the notches 47 and 47 'exist can be used as the marker 1.

FIG. 4 is a sectional view taken along the line IV-IV of FIG. FIG. 4 shows a sheet metal element 22 which is cast with a plastic coating 23. The marker 1 is, for example, a recess 7 in the form of a slope 8 of the sensor base 38. This marker 1 can be configured as described in FIG. The marker 1 is formed directly during the molding of the plastic coating 23 of the sensor support, for example by means of a corresponding molding tool. This makes the mounting of the measuring element 46 in the sensor cavity more accurate.

FIG. 5 shows a structural element 2 with a rectangular cutout 15, for example. In the cutout 15, an electronic chip or element, for example a measuring element 46, here shown in broken lines, must be inserted very precisely in the center. At the mounting position of the measuring element 46 and outside the notch 15, the structural element 2
For example, two markers 1, 1 'as shown in FIGS. The distance between the markers 1 and 1 ′ does not necessarily have to be equal to the length of the edge 51 of the notch 15 or the length of the edge facing the edge 51. When the markers 1 and 1 'are directly connected, a virtual line 52 is formed. This imaginary line 52 has a predetermined distance 56 from the edge 51 of the notch 15 or the edge facing the edge 51.
have. The edge 51 or an edge facing the edge 51 and the virtual line 52 extend in parallel with each other. However, it is not always necessary that the edge 51 or the edge facing it and the virtual line 52 extend in parallel with each other. It is only necessary to know the mutual positions of the virtual line 52 and the edge 51 or the edge facing it. For example, there is a coordinate system 57, which has an origin defined for the structural element 2. For example, the distance between the markers 1 and 1 ', the coordinate system 57
, The coordinates of the markers 1 and 1 ′, the virtual line 52 and the edge 5
Knowing the mutual spacing 56 between one or the opposing edges and the geometry and size of the cutout 15 allows the exact location of the mounting for the measuring element 46 to be performed.

This makes it possible to mount the markers 1, 1 'on the structural element 2 outside the mounting position. Since certain information is known, for example the shape (eg rectangle) and dimensions of the notch, at least one marker 1 on the structural element 2 is appropriately selected and the position of the marker 1 relative to the notch 15 The mounting position can be determined by appropriately selecting. It is not necessary to place the element to be mounted in the cutout 15 or on the ridge. The mounting position can also be part of the flat surface of the structural element 2.

FIG. 6 shows a camera image of the image processing system.
This camera image is processed into a dimensional image by the evaluation computer 81 (FIG. 7) according to a specific algorithm. The rounded edges form an optimal transition in image capture, and thus produce ideal contrast. For example, the bent portion 63 and the edge 64 can be accurately defined. The bent portion 63 and the edge 64 are indicated by broken lines.
The smooth glossy surface of the structural element 2 ensures that no obstructions occur in the dimensional image.

FIG. 7 schematically shows an apparatus for measuring bright field illumination. The structural element 2 is illuminated by an illumination source 70 with coaxial light 71. The camera 72 captures the reflected light 75 from the structural element 2. Camera 72 and illumination source 70
Are arranged at an angle α to each other. The scattered light 76 from the structural element 2 is not captured by the camera.
The reflective surface looks bright. This is because the reflection surface is grasped by the camera 72. The scattering surface appears dark. This is because the scattering surface is not grasped by the camera 72.

The principle of dark field illumination is similar. The illumination source 70 illuminates the structural element 2 with coaxial light. However, in this case the camera 7 shown in broken lines
2 captures the scattered light 76 because of its different position with respect to the structural element 2, so the scattering surface looks bright and the reflecting surface looks dark. The camera 72 is connected to an evaluation computer, and the evaluation computer evaluates the data of the camera 72 and sends parameters necessary for determining the mounting position to the positioning system 82.

FIG. 8 shows an ideal vertically shaped edge 3
FIG. 8a schematically shows the mode of operation of bright field illumination at (a) of FIG. Illumination source 70
The angle α between the camera and the camera 72 is the same or almost zero.

In FIG. 8a, at the ideally formed edge 3 four light rays 87 schematically shown
Are reflected, so the camera image of FIG. 8b, which is a plan view of FIG. 8a, shows a white surface.

In FIG. 8c, the edge 3 is, for example, beveled, so that the second ray 87
It cannot be reflected inside 2. This is true for all rays incident on the area of the slope 8 which serves as the marker 1. In the camera image (FIG. 8d), there is a strip having a width 88, which is equal to the vertical projection width of the marker 1 in FIG. 8c.

The mounting of the electronic chip or element into the structural element 2 takes place as follows.

After the mounting position of the electronic chip or element is optically determined and determined by the evaluation computer 81, this information is sent to a positioning system 82, which uses the positioning system 82 for positioning, for example, an element such as a measuring element. 46 is gripped by gripper system 84,
This causes the element to be moved in a plane parallel to the mounting position and then moved perpendicular to this plane into a predetermined mounting position. Depending on the arrangement of the illumination source and the camera, after the gripper system has moved in the plane,
A more accurate mounting is possible if the mounting position is determined anew and the possibly existing errors and tolerances of the gripper system are compensated for by the correction movement by the positioning system 82. The movement perpendicular to the mounting position then brings the element exactly to the mounting position.

[Brief description of the drawings]

1a-g are plan and cross-sectional views of various embodiments of a marker of a structural element.

FIGS. 2a to 2f show two possibilities for producing a marker-free recess and a marker of a structural element. FIGS.

FIG. 3 is a diagram showing an example of a sensor support of the air mass measurement device.

FIG. 4 is a sectional view taken along the line IV-IV in FIG. 3;

FIG. 5 shows two markers on the structural element outside the notch.

FIG. 6 is a diagram showing an original image of an observation camera.

FIG. 7 is a diagram schematically illustrating bright field illumination or dark field illumination.

FIGS. 8A to 8D are diagrams showing operation modes of bright field illumination in one marker.

[Explanation of symbols]

1 marker, 1 'marker, 2 structural element,
3 edges, 6 ridges, 7 recesses, 8 slopes,
12 surface, 13 curved surface, 15 notch, 1
6 bottom, 17 marker, 18 marker, 20
Sensor support, 21 basic support, 22 sheet element, 23 plastic coating, 24 sinking edge, 27 sensor cavity, 28 sensor cavity bottom,
35 passage, 36 support surface, 38 sensor base surface, 4
2a edge, 42b edge, 42c edge,
42d edge, 43a edge, 43b edge, 43c edge, 43d edge, 46 measuring elements, 47 notch, 47 'notch,
51 edge, 52 virtual line, 56 interval, 57
Coordinate system, 63 bends, 64 edges,
70 illumination source, 71 coaxial light, 72 camera, 7
5 reflected light, 76 scattered light, 81 evaluation calculator,
82 positioning system, 84 gripper system,
87 rays, 88 width, α angle

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Gerhard Huftle Germany Aspach Weierstraße 29 (72) Inventor Rainer Schart Germany Esslingen im Gaugenmeier 10 (72) Inventor Uwe Konzermann Asperk Schwa, Germany Rubenweg 14 (72) Inventor Andreas Stark Germany Lauscha Ahornsturth 16

Claims (11)

[Claims] 1. A structural element comprising at least one marker recognizable by an optical image processing system, wherein at least one marker has at least one edge (3), said edge being inclined. (8) or curved (1
3) or structural elements with optically recognizable markers, characterized in that they are flattened. 2. The slope (8) of at least one marker,
2. The structural element according to claim 1, wherein the curved surface or the flat surface is formed in such a way that a good contrast occurs in the image processing system. 3. The presence of at least one marker (1) outside or within the mounting position of the at least one element to be mounted on the structural element (2). Claim 2
The described structural element. 4. The relative position of the at least one edge (3) in the structural element (2) is determined by the image processing system and, from the position of the at least one existing edge (3), at least one edge to be attached 4. The structural element according to claim 3, wherein the mounting position of the element can be determined. 5. The method according to claim 1, wherein the at least one marker is produced by a recess provided with an edge of the structural element or a ridge. 4. Structural element according to 4. 6. The at least one marker (1) has a circular and / or angular cross section at the level of the surface (12) of the structural element (2). Item 6. The structural element according to Item 5. 7. The structural element (2) has a sensor cavity (27) as a notch (15) for receiving a measuring element (46) of an air mass measuring device, in particular a measuring device of the intake air mass of an internal combustion engine. Equipped sensor support (2
The structural element according to claim 1, wherein the structural element is 0). 8. The sensor according to claim 1, wherein the at least one marker is formed by a chamfered edge of the sensor cavity or a recess along the edge. Item 7. The structural element according to Item 7. 9. The method according to claim 1, wherein the structural element is made of metal, semiconductor material, ceramic or plastic.
Structural element described in section. 10. The method for recognizing at least one marker of a structural element according to claim 1, comprising an at least one marker recognizable by an optical image processing system, wherein the image processing system has at least one marker.
It has an optical illumination source (70), an observation camera (72) and an evaluation calculator (81), wherein at least one
A method for recognizing at least one marker of a structural element, characterized by using bright or dark field illumination in coaxial light (71) to recognize one marker. 11. The method for determining the mounting position of at least one element on a structural element according to claim 1, comprising at least one marker recognizable by an optical image processing system. By determining the relative position of the at least one marker (1) on the element (2) by the image processing system, the mounting position of the at least one element (46) is determined, and this mounting position is then transmitted to the positioning system (82). Supplying, and finally placing said at least one element (46) in a determined mounting position on the structural element (2) by means of a positioning system (82). How to determine the location.