JP3222664B2 - Member position / posture measuring method and member joining method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring the position and orientation of a member and a method for joining members.

[0002]

2. Description of the Related Art Heretofore, steel frame construction work has been carried out by cooperation between a husband and a crane operator, and the alignment when joining steel frames has been performed visually.

[0003]

As described above, the steel frame construction work relies on human power, and its mechanization and automation have been desired.

The present invention has been made in view of such a demand, and a purpose thereof is to automatically measure the position and posture of members such as steel frames and to automatically join those members. It is to provide a method that can be.

[0005]

In order to achieve the above-mentioned object, a first aspect of the present invention provides a process of projecting a double slit light on a member, an image of the member, and a cut line image of a projected portion. Obtaining, the step of calculating the position of the projected part, and the step of calculating the axial vector of the member based on the cutting line image, with respect to a plane orthogonal to the axial vector, Generating a projection of the cutting line image; calculating a rotation angle of the member around the axial vector based on the projection of the cutting line image; capturing the member; Calculating the part; and
This is a posture measurement method.

According to a second aspect of the present invention, the different members are moved so that the end faces of the different members coincide with each other while calculating the positions and orientations of the different members by the method for measuring the position and orientation of the members according to the first invention. This is a method for joining members, characterized in that the members are joined together.

[0007]

According to the first aspect of the present invention, the member is projected with double slit light, the member is imaged, and a cut line image of the projected portion is obtained.
Calculate the position of the projected part, calculate the axial vector of the member based on the cutting line image, generate a projection of the cutting line image on a plane orthogonal to the axial vector, and By calculating the rotation angle of the member around the axial vector based on the projection, imaging the member and calculating the end of the member,
It measures the position and orientation of the member.

Further, in the second invention, the position / posture measuring method according to the first invention is used to measure the position / posture of different members.
While calculating the posture, the different members are moved and joined so that the end faces of the different members match.

[0009]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a configuration diagram of an apparatus necessary for implementing a method for measuring the position and orientation of a member. This device has a double slit projector 3, an infrared image CCD camera 5 having an interference filter 7, a gray scale image CCD camera 9, a computer 11, and displays 13 and 15. In addition,
Reference numeral 1 denotes an H-section steel (steel frame) as a member.

The double-slit projector 3 has a cylindrical lens. Through this cylindrical lens, two slit-shaped infrared lasers (double-slit light) radiating parallel to the optical axis are irradiated by an H-shaped steel. Irradiate 1 The interference filter 7 transmits only light in the infrared region and reflects other light. The infrared image CCD camera 5 captures an image of the H-beam 1 via the interference filter 7. The gray-scale image CCD camera 9 images the H-section steel 1. The computer 11 processes image signals sent from the infrared image CCD camera 5 and the grayscale image CCD camera 9,
The position and orientation of the H-beam 1 are measured. Display 1
3 is a cutting line image 2 captured by the infrared image CCD camera 5
3 is displayed. The cutting line image 23 is a reflection image formed by irradiating the H-shaped steel 1 with the double slit light. Display 1
5 displays a gray-scale image 19 of the H-section steel 1.

Next, the procedure for measuring the position and orientation of the H-beam 1 will be described with reference to the flowchart shown in FIG. The double slit light projector 3 emits double slit light to the H-section steel 1 (step 201), and an infrared image of the H-section steel 1 is captured by the infrared image CCD camera 5 (step 202). Cutting line images 23a and 23 of the projected part
The image signal relating to b is sent from the infrared image CCD camera 5 to the computer 11, and the computer 11 calculates the position of the projected portion of the H-section 1 from the cutting line images 23a and 23b (step 203).

To calculate the position of the projected part, the principle of triangulation is used. FIGS. 3 and 4 are diagrams for explaining the principle of the triangulation. In order to simplify the description, a case where the position of an object in a two-dimensional space is measured will be described as an example.

3 and 4, reference numeral 2 denotes a light projector, 4 denotes an object, and 20 denotes a position of a lens of a CCD camera for infrared image.
Reference numeral 1 denotes an image plane (image plane) of the infrared image CCD camera. P indicates a projection point on the object 4 and P 'indicates an image on the image plane 21. The positional relationship between the infrared image CCD camera and the slit projector 2 is predetermined, and the distance is L. Further, since the mounting position of the slit light projector 2 is also determined, the angle β is known.

In FIG. 4, assuming that the coordinates of the point P are (X, Y), X = Ltan β / (tan α + tan β) (1) Y = (Ltan α + tan β) / (tan α + tan β) ( 2)

When the focal length of the camera is f (known) and the X coordinate of the image P 'on the image plane 21 is X ₀ , α = tan ^-1 (X ₀ / f) (3) Become.

Therefore, when X ₀ is measured, α is obtained from equation (3), and the coordinates of P are determined by equations (1) and (2).

Next, referring to FIG.
An axial vector 25 of the H-section steel 1 is calculated based on 3b (step 204).

The axial vector is calculated as follows. FIG. 5 shows cutting line images 23a,
3b is shown. The magnitudes τu and τv of the vertical and horizontal displacements at which the correlation between the two cut line images 23a and 23b on the image plane is maximum are obtained. Next, cutting line images 23a and 23b
And the center of gravity of this τu in the horizontal direction and τv in the vertical direction
The three-dimensional coordinates of the moved point are obtained, and an axial vector 25 connecting the two points is calculated. Next, the axial vector 2
5, the cutting line images 23a and 23b
Are projected (step 205).

FIG. 6 is a schematic diagram showing the case where this projection is performed, in which the cut line images 23a and 23b are projected on the surface 27. FIG. FIG. 7 is a diagram showing the projection 29 on the surface 27.

Next, projection 2 of cutting line images 23a and 23b
9 and the aspect table are compared to determine the rotation angle of the H-beam 1 (step 206).

FIG. 8 shows an image pattern of the H-section steel stored in the aspect table. As shown in FIG. 8, the aspect table stores an image pattern when light is projected from the A direction in accordance with the rotation of the H-shaped steel. In FIG. 8, an image indicated by a thick black line is an image when light is projected from the A direction. Although FIG. 8 shows six types of patterns rotated by 30 degrees, a large number of patterns having a small rotation angle may be stored.

In the case of this embodiment, the projection 2 as shown in FIG.
Since 9 is obtained, it is found that the angle coincides with (b) of the aspect table, and it is determined that the rotation angle of the H-section steel is 30 degrees.

Next, the edge of the H-beam 1 is calculated based on the gray-scale image of the H-beam 1 obtained by the gray-scale image CCD camera 9 (step 207).

FIG. 9 is an explanatory diagram of the calculation of the edge. The brightness level of the axial direction vector 25 on the grayscale image is as shown in FIG. 9, and the edge of the H-beam 1 can be detected by differentiating this brightness level.

As described above, in this embodiment, the double slit light projector 3, the infrared image CCD camera 5, the grayscale image CCD
The position and orientation of the H-beam can be measured using the camera 9 and the like.

FIG. 10 is an explanatory view in the case of joining steel frames using the method described above. In FIG. 10, 31, 3
Reference numeral 5 denotes an existing H-beam, and an H-beam 33 is joined between the H-beams 31 and 35. The position and posture of the H-section steel 31 are determined by a double slit projector 3a and a CCD camera 5 for infrared image.
a, Measurement is performed using the gray-scale image CCD camera 9a. In addition, as shown in FIG.
Are joined while being lifted by a lifting machine 37. That is, H
Double-slit floodlight 3
b, Measurement is performed using the infrared image CCD camera 5b and the grayscale image CCD camera 9b. Then, the lifting machine 37 is controlled so that the cross sections of the H-section steel 31 and the H-section steel 33 match.

In the above-described embodiment, an H-shaped steel is taken as an example. However, the present invention is not limited to the H-shaped steel, but is widely used for measuring the position and posture of members such as various steel materials and joining them. .

[0028]

As described above, according to the present invention, the position and orientation of members such as steel frames can be automatically measured and these members can be automatically joined.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an apparatus for measuring the position and orientation of a member.

FIG. 2 is a flowchart showing a procedure for measuring the position and orientation of a member.

FIG. 3 illustrates the principle of triangulation.

FIG. 4 illustrates the principle of triangulation.

FIG. 5 is a sectional line image 23a, 23 on the display 13.
Diagram showing b

FIG. 6 is an explanatory diagram when projecting cutting line images 23a and 23b onto a plane 27 perpendicular to the axial direction vector 25;

FIG. 7 shows a projection 29 on the surface 27.

FIG. 8 is a diagram showing an aspect table.

FIG. 9 is an explanatory diagram of edge detection of the H-section steel 1;

FIG. 10 is an explanatory view in the case of joining an H-section steel 31 and an H-section steel 33;

11 is a view showing a lifting machine 37 for lifting the H-section steel 33. FIG.

[Explanation of symbols]

 1, 31, 33: H-section steel 3: Double slit projector 5: CCD camera for infrared image 9: CCD camera for gray image 11: Computer 13, 15: Display

Continuation of the front page (72) Inventor Kazuo Nakazawa 3-11-16 Hiyoshi, Kohoku-ku, Yokohama-shi, Kanagawa Prefecture 4-C, Banno Corp. (56) References JP-A-5-231836 (JP, A) JP-A-62-1101379 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) G01B 11/00-11/30

Claims (2)

(57) [Claims] A step of projecting double-slit light onto a member; capturing an image of the member; obtaining a cutting line image of the projected portion;
Calculating the position of the projected part; calculating the axial vector of the member based on the cutting line image; and forming the cutting line image on a plane orthogonal to the axial vector. Generating a projection of, and a step of calculating a rotation angle of the member about the axial vector based on the projection of the cutting line image; capturing the member and calculating an end of the member And a method for measuring the position and orientation of a member comprising: 2. A method according to claim 1, wherein different members are moved and joined so that the end faces of the different members coincide with each other while calculating the positions and postures of the different members. Characteristic joining method of members.