JP2000329520A - Coil position detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a coil position detector capable of exactly operating the position even for a mirror shape. SOLUTION: A slit light scanner 12 for irradiating with laser slit light, a TV camera 10 photographing images, an image synthesizer 14 for extracting a part changing brightness and forming binarization processed image, a shape operation means 16 calculating the cross sectional shape data of the part of changing brightness and a coil operation device 18 for extracting the cross sectional shape data of the coil part and calculating the coil width, the width center position, coil diameter and the diameter center position. The slit light scanner 12 irradiates the coil with a laser slit light so that a plurality of the parts changing brightness exist when seeing the coil in diameter direction. The coil operation device 18 calculates the coil width and the width direction center position for the part that a plurality of cross sectional shape data exist when the cross sectional shape data is projected to the coil diameter direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for non-contact measurement of a three-dimensional shape (position) such as the position and height of an object, and more particularly to an overhead crane which is operated unmanned in a coil yard of a steelworks. And a coil position detecting device for detecting a center position of the coil and the like.

[0002]

2. Description of the Related Art As a method for easily measuring three-dimensional information such as the position and height of an object, a light cutting method has been well known. In this light cutting method, the object to be measured is irradiated with laser slit light, and the shape pattern (light cutting line) of the laser slit light projected on the surface of the object to be measured is changed from a direction different from the irradiation direction of the laser slit light. Take an image with a TV camera. At this time, if the measured object has irregularities, the light cutting line is deformed on the captured image according to the irregularities of the measured object. Therefore, the shape of the object to be measured is calculated based on the principle of triangulation from the position of the light cutting line (deformation amount) when the image is taken by the television camera and the projection angle of the laser slit light. A coil position measuring apparatus is applied to the measurement of the width, the center of the diameter, and the like of the coil in the coil yard using the object to be measured as a coil.

Next, a case where this method is applied to a coil position measuring device will be described. Take an image with a TV camera,
In the processed image, the portion of the light section line is usually bright (that is, the brightness is high). Therefore, a high-luminance portion and a low-luminance portion are divided by a binarization process, and only the high-luminance portion is extracted. Then, the three-dimensional shape of the coil is calculated based on the principle of triangulation from the extracted portion and the projection angle of the laser slit light.

[0004]

As described above, the coil position detecting device irradiates a slit-shaped laser beam onto the coil surface and images a light cutting line appearing on the coil surface to create three-dimensional shape data. Then, the center position of the coil and the like are calculated based on the shape data and the projection angle of the laser.
Then, the crane is controlled using the calculation result to carry the coil or the like. Here, if the surface property of the coil to be detected is a diffuse property of diffusely reflecting the irradiation light, the laser light irradiated on the coil surface is diffusely reflected over a wide angle. Therefore, regardless of the shape of the coil, the intensity of light input to the television camera is always stable.

However, when the properties of the coil surface to be irradiated with laser light are close to mirror-like, the irradiated laser light is not diffusely reflected but specularly reflected (= specularly reflected). Therefore, the intensity of light input to the television camera greatly changes depending on the position of the coil surface on which the laser light is irradiated.

FIG. 11 is a diagram showing a positional relationship between a coil for irradiating a laser beam and a television camera. For example, when the irradiated laser light is diffused due to the properties of the coil surface, the intensity of the light input to the television camera is substantially constant regardless of whether the laser light is applied to point A or B. On the other hand, when the irradiated laser light is regularly reflected due to the properties of the coil surface, the light that is regularly reflected is not input to the TV camera when the laser light is applied to the point A, so that the light input to the TV camera is not strong. However, when the light is applied to the point B, the light that is regularly reflected enters the television camera, so that the light at this time is very strong. Here, since the shape of the coil is usually cylindrical, the irradiation position of the laser beam when the specularly reflected light is input to the TV camera in this way depends on the arrangement of the laser light source and the TV camera and the inclination of the coil surface. Determined, and its location is limited to a specific portion of the coil surface.

FIG. 12 is a diagram showing a screen subjected to an image pickup process. If position detection is performed by a conventional method using a coil having a surface texture that causes specular reflection, regular reflection light is input to the television camera depending on the laser light source, the shape of the coil, and the positional relationship between the television camera as described above. May be done.
When extremely strong light such as specular reflection light enters the television camera, the lens and imaging surface of the television camera (for example, CC)
In the optical system composed of D), the input light is reflected,
Causes scattering and the like. Therefore, the light focused on the imaging surface has a wider range than the actual laser light. In some cases, a phenomenon such as a ghost image generated between the lens and the imaging surface may be reflected. For this reason, on the screen, a portion having a high luminance is generated even in a portion other than the irradiation portion to be actually obtained, and it is not possible to accurately detect a light cutting line due to laser light irradiation.

Therefore, depending on the position where the television camera receives the reflected light, the spread of the light generated by the regular reflection may reach outside the true coil edge. Therefore, even a portion where the coil does not actually exist is detected as if the coil exists. When the coil width and the center position are calculated by the conventional position detecting device, there is a problem that an accurate coil width or the like cannot be obtained because the coil width is detected as wide as the light is spread.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problem. Even if the surface of the coil is mirror-like,
It is an object of the present invention to obtain a coil position detecting device that can accurately calculate the position of a coil.

[0010]

A coil position detecting device according to the present invention is mounted on an overhead crane for transporting a coil, and irradiates a plurality of linear laser slit beams to the coil with a laser beam projecting means. Imaging means attached to the crane, for imaging an image with the coil as a subject,
The image pickup means processes the image taken by the image pickup means to determine and extract a portion where the brightness has changed due to the irradiation of each laser slit light, and to extract and generate a processed image. Shape calculating means for calculating three-dimensional shape data of the changed portion; and, among the three-dimensional shape data calculated by the shape calculating means, determining and extracting the three-dimensional shape data of the coil portion, and extracting the extracted three-dimensional shape data. Projecting in the radial direction of the coil to calculate at least the width of the coil and the center position of the width, and projecting the extracted three-dimensional shape data in the coil width direction to at least determine the diameter of the coil and the central position of the diameter A coil calculating means for calculating, wherein the laser light projecting means has a portion where the brightness changes due to the irradiation of the plurality of laser slit lights at any position when the coil is viewed in the radial direction. Irradiating each laser slit light so, also, the coil calculating means, when projecting the three-dimensional shape data extracted is determined that the coil portion to the coil radial direction,
At least the width of the coil and the center position in the width direction are calculated based on a portion where a plurality of three-dimensional shape data calculated by the irradiation of the plurality of laser slit lights exist. In the present invention, the laser light projecting means is attached to an overhead crane that carries the coil, and irradiates a plurality of linear laser slit lights so as to cut the coil.
When irradiating, when the coil is viewed in the radial direction, the irradiation is always performed so that there are a plurality of irradiated portions of the laser slit light at any position of the coil. An image taken by the image pickup means is processed by the image synthesizing means, and a portion whose brightness has been changed by the irradiation of each laser slit light is determined and extracted to create a processed image. The shape calculation means performs 3 based on the processed image.
Create dimensional shape data. The coil calculating means projects the three-dimensional shape data of the coil in the radial direction of the coil, obtains the center position and the coil width in the width direction of the coil, and projects the three-dimensional shape data of the coil in the width direction of the coil. The radial center position and the coil diameter are determined. The three-dimensional shape data of the coil portion is determined and extracted from among the three-dimensional shape data calculated by the shape calculation means, and the extracted three-dimensional shape data is projected in the radial direction of the coil to determine the width of the coil and the center position of the width. Is calculated. At this time, the width of the coil and the center position of the width are calculated based on the portion where the plurality of three-dimensional shape data calculated by the irradiation of the plurality of laser slit lights exist. Also, the extracted three-dimensional shape data is projected in the width direction of the coil to calculate the diameter of the coil and the center position of the diameter.

Further, in the coil position detecting device according to the present invention, the laser beam projecting means outputs a beam projecting angle signal indicating a beam projecting angle of each laser slit beam, and the coil calculating device comprises a plurality of laser slit beam projecting devices. Is determined on the basis of the projection angle signal based on the projection angle signal. In the present invention, the laser beam projecting means outputs a beam projecting angle signal which is information obtained by irradiating the laser slit light. In the radial projection, the coil calculating means determines a portion where a plurality of three-dimensional shape data exists due to irradiation of a plurality of laser slit lights based on the light projection angle signal.

Further, in the coil position detecting device according to the present invention, the laser beam projecting means irradiates a plurality of laser slit beams by scanning the laser spot two-dimensionally. In the present invention, when irradiating a plurality of laser slit lights, the laser light projecting means two-dimensionally scans and irradiates a laser spot which is a point of the laser light.

Further, in the coil position detecting device according to the present invention, when projecting the three-dimensional shape data in the radial direction of the coil, the coil calculating means sets the diameter of the coil to a perpendicular line and a line segment perpendicular to the overhead crane. Projected onto a plane parallel to. In the present invention, when projecting the three-dimensional shape data in the radial direction of the coil, the coil calculating means sets the diameter of the coil as a perpendicular,
Also, project onto a plane parallel to the vertical line segment on the overhead crane so that the highest part of the coil is always included.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. FIG. 1 is a configuration diagram for explaining the measurement principle of the coil measurement device of the present invention.
In the figure, a coil 3 is placed on a reference plane (floor surface) 1. A television camera 10 serving as an imaging unit is arranged so that its center axis is orthogonal to the reference plane 1, converts a captured image into a video signal, and transmits the video signal. The slit light scanning device 12 serving as a laser light projecting unit is arranged at a position different from the television camera 10. The slit light scanning device 12 generates the laser slit light 12 a from the laser spot light, scans the laser slit light 12 a, and irradiates the laser so as to cut the coil 3. Further, a light projection angle signal representing the light projection angle θ based on the scanning is transmitted. The image synthesizing device 14 serving as an image synthesizing unit converts the binary processed image signal and the light projection angle image signal based on the video signal transmitted from the television camera 10 and the light projection angle signal transmitted from the slit light scanning device 12. Generate processing. Shape calculation device 16 serving as shape calculation means
Calculates three-dimensional cross-sectional shape data based on the binary processed image signal and the projection angle image signal generated and processed by the image synthesis device 14. Coil calculation device 1 serving as coil calculation means
Numeral 8 determines the diameter, width, and the like of the coil 3 based on the three-dimensional cross-sectional shape data obtained by the shape calculation device 16. At that time,
A component generated by the spread of the laser spot light based on the regular reflection is removed. The configuration of the coil position detecting device is as described above. Before describing the overall operation of the coil position detecting device of FIG. 1, the measuring method, the image synthesizing method, the relationship and the shape between the position of the laser slit light and the projection angle θ are described. From the viewpoint of the operation principle,
The operation of each related device will be described.

(A) Measuring Method FIG. 2 is a diagram showing a configuration of the slit light scanning device 12. The measurement method according to the present embodiment will be described with reference to FIG. As a measuring method, a method generally called a light section method is used. In the figure, a semiconductor laser 20 emits a laser spot light. The drive motor 22a controls the rotation of the first scanning mirror 22. The first scanning mirror 22 is
The laser spot light emitted from the semiconductor laser 20 is reflected while rotating. Thereby, the laser spot light scans, and laser slit light is generated. Here, the direction of the generated laser slit light is controlled by the drive motor 22a as shown in FIG.
The rotation of the first scanning mirror 22 is controlled so as to be in the y-axis direction. Further, the drive motor 24a controls the rotation of the second scanning mirror 24, and controls the irradiation position of the generated laser slit light in the x-axis direction in FIG. Thereby, the generated laser slit light is scanned in the x-axis direction, and a plurality of laser slit lights are irradiated. At the same time, the projection angle θ determined by the second scanning mirror 24
Is transmitted to the image synthesizing device 14 as a projection angle signal.
The television camera 10 outputs the captured image to the image synthesizing device 14 as a video signal.

Then, the second scanning mirror 24 is moved from θ to Δ
Rotate by θ and execute again. Such an operation is repeated an appropriate number of times. Here, in order to measure the coil position and the like, the value of the projection angle θ is necessary. If a proper number of laser slit lights can be irradiated on the coil, and the value of θ can be determined, the value of Δθ to be rotated is changed each time. It does not matter if they are not the same.

The image synthesizing device 14 processes the video signal of the television camera 10 while synthesizing the video signal by each light cutting line. Then, a binary processed image signal and a projection angle image signal are generated from the video signal and the projection angle signal. The shape calculation device 16 performs the image processing by the image synthesis device 14.
A plurality of three-dimensional cross-sectional shape data is calculated using the value-processed image signal and the projection angle image signal. Based on these calculation results, the overall shape of the coil 3 is obtained.

Here, in order to improve the measurement accuracy, a light cutting line (laser slit light having a projection angle θ) and a light cutting line (projection angle θ) are used.
It is necessary not to irradiate the laser light unnecessarily with the laser slit light of + Δθ. Therefore, the slit light scanning device 12 shown in FIG. This is controlled in synchronization with the drive motor 24a, and until the projection angle θ of the laser slit light changes to θ + Δθ,
The laser slit light is not irradiated on the coil 3. This is because the projection angle θ of the laser slit light is θ + Δθ
The laser spot light may not be generated in the semiconductor laser 20 until it changes to. The smaller the rotation pitch Δθ of the second scanning mirror 24 is, the more the shape resolution of the coil 3 is improved. However, on the other hand, the arithmetic processing increases, and the measurement time increases.

The coil calculating device 18 calculates the center position, width, etc. of the coil based on the respective shape data and the light projection angle θ.

(B) Image Synthesizing Method FIG. 3 is a block diagram showing the configuration of the image synthesizing device 14. The video signal transmitted from the television camera 10 is A /
The signal is converted into a digital signal by the D converter 30 and input to the maximum luminance image calculation unit 31. Maximum brightness image calculation unit 31
Is composed of a comparator 31a, a selector 31b and a maximum luminance image memory 32. The maximum luminance image calculation unit 31 obtains the video signal of the maximum luminance level of each pixel area by the comparator 31a and the selector 31b, and stores the video signal in the corresponding pixel area in the maximum luminance image memory 32.

The processing procedure until the maximum luminance image calculation section 31 stores the maximum luminance image signal will be described in detail. A
If / D converter 30 the video signal a _c of the pixel region that is through is input, the comparator 31a from the maximum brightness image memory 32, reads the signal a _m of the pixel area corresponding to the video signal a _c. Then, comparing the luminance level of the signal a _m brightness level and a maximum brightness image memory 32 of the video signal a _c. Here, in the case of a _c> a _m transmits the selector signal to the selector 34a of the selector 31b and the coded image calculation unit 34. When the selector 31b selector signal is input, the signal a _m of the maximum brightness image memory 32
To the video signal a _c (that is, a _c = a
_m ). In the case of a _c ≦ a _m, not rewrite (i.e., a _m = a _m). Such processing is performed by the TV camera 1
Sequentially performed for the video signal a _c inputted from 0.
Therefore, the maximum brightness image level of each pixel region is stored in the maximum brightness image memory 32 as a maximum brightness image signal.

The projection angle signal of the laser slit light transmitted from the slit light scanning device 12 is converted into a digital signal by the A / D converter 33 and input to the coded image calculation unit 34. The coded image calculation unit 34 includes a selector 34a and a projection angle image memory 35. In the coded image calculation unit 34, the projection angle signal at the time when the maximum luminance image level is obtained for each pixel area is projected to the pixel area of the projection angle image memory 35 corresponding to the maximum luminance image memory 32. It is coded and stored as a projection angle image signal representing the angle θ.

The processing procedure for storing the projection angle signal by the coded image calculation section 34 will be described in detail. Comparator 31a of the maximum brightness image calculation unit 31 compares the luminance level of the signal a _m brightness level and a maximum brightness image memory 32 of the video signal a _c, when it is determined that satisfies the a _c> a _m, a selector signal Is output. When the selector 33a receives the selector signal, the signal b of the projection angle image memory 34 corresponding to the pixel area whose luminance level is compared
The _m, rewrites the projection angle image signals b _c obtained by coding the projection angle θ represented by the projection angle signal transmitted at that time.
Such processing is sequentially performed based on the video signal a _c input from the television camera 10 and the light projection angle signal b _c input from the slit light scanning device 12. Therefore, the angle signal image memory 35, projection angle θ when the maximum brightness image level in each pixel area is stored as the projection angle image signal b _m.

Further, the video signal transmitted from the television camera 10 is converted into a digital signal by the A / D converter 36 and input to the minimum luminance image calculation unit 37. The minimum brightness image calculation unit 37 includes a comparator 37a, a selector 37
b and a minimum brightness image memory 38. The minimum luminance image calculation unit 37 obtains the video signal of the minimum luminance level of each pixel region by the comparator 37a and the selector 37b, and stores the video signal in the corresponding pixel region in the minimum luminance image memory 38.

The minimum luminance image calculation section 37 outputs the minimum luminance image
The processing procedure up to storing the image signal will be described in detail. Ko
The comparator 37a is connected to an image via the A / D converter 36.
Video signal a of the elementary area_c Is input, the minimum brightness image
From the moly 38, the video signal a_c Of the pixel area corresponding to
Signal a_miIs read. Then, the video signal a_c Brightness
Level and signal a of minimum brightness image memory 38_miBrightness level
Compare with Where a_c <A_miIn the case of
And the selector 34 of the coded image calculation unit 34
Transmit the selector signal to a. Selector 31b is select
When the data signal is input, the signal of the minimum brightness image memory 38
a_miIs the video signal a_c (That is, a_c =
a_mi). a_c ≧ a_miIs not rewritten (that is,
a_mi= A _mi). Such processing is performed by the TV camera 10
Video signal a input from_c Are performed sequentially. did
Therefore, the minimum brightness image memory 38 stores the minimum pixel area.
The luminance image level is stored as the minimum luminance image signal.

FIG. 4 is an explanatory diagram conceptually showing the arithmetic processing of the image synthesizing device 14. FIG. 4A is a diagram illustrating the maximum luminance image level between AA ′. FIG. 4 (b)
It is a figure showing the minimum luminance image level between BB '. FIG. 4C is a diagram showing the light projection angle θ when the maximum luminance image level is obtained between CC ′ (AA ′). In FIG. 4B, the minimum luminance image level of the coil portion is higher than the luminance of the reference plane because the reflected light (background light) of the light other than the laser spot light is affected.
The image synthesizing device 14 is, as described above, the TV camera 10
Real-time processing of the video signal imaged at the step (a), the maximum luminance image level and the minimum luminance image level of each pixel area are detected, and the maximum luminance image memory 32 and the minimum luminance image memory 3 are obtained.
8 is maintained. Further, the projection angle signal at the timing when the image reaches the maximum luminance image level (normally, at the position irradiated with the laser spot light, when a corresponding point in the visual field is hit) is stored in the projection angle image memory 35 at the maximum. Brightness image memory 3
2 is recorded in the pixel area corresponding to 2. Therefore, it is possible to simultaneously obtain a maximum or minimum luminance image signal obtained by combining a plurality of laser slit lights and a projection angle image signal.

(C) Extraction of position and projection angle information of laser slit light In order to extract a light cutting line from the above-described maximum luminance image signal, minimum luminance image signal and projection angle image signal, the following equation (1) is used. ) Is performed, and the luminance level due to the influence of the background light (light generated by an influence other than the laser light) is subtracted. Luminance image level = maximum luminance image level−minimum luminance image level (1) A luminance image level from which the influence of the background light has been subtracted by the image calculation of equation (1) is calculated. To extract only a high-brightness portion (usually a light cutting line) above a threshold level as a binarized image signal. In the present embodiment,
As described above, the minimum luminance image calculation is performed at the same time, the difference between the maximum luminance level and the minimum luminance level is calculated, and then the binarization processing is performed by the comparing unit 39. Alternatively, the comparison unit 39 may perform a binarization process to extract a high luminance portion.

In the image synthesizing device 14, the luminance image memory 3
The binarized image signal stored in 9a is transmitted. In addition, the projection angle image signal is transmitted from the projection angle image memory 35.

(D) Principle of Shape Calculation Next, a binarized image signal and a projection angle image signal are used.
The calculation of three-dimensional cross-sectional shape data based on triangulation will be described. The shape calculation device 16 obtains the entire shape of the coil 3 by calculating the three-dimensional coordinates of each of the light cutting lines for the plurality of laser slit lights generated by the slit light scanning device 12. This shape calculation is based on a triangulation method. The slit light scanning device 12 emits the laser slit light 12 a onto the coil 3 at an emission angle θ. The height z of the point (x ', y') where the laser light extracted from the image obtained by capturing the state is applied
(X ', y') is expressed by the following equation (2) in consideration of the perspective effect of the captured image. z (x ′, y ′) = Z ₀ − {X ₀ − (1−z (x ′, y ′) / a) x} × tan θ (x ′, y ′) (2) x ′: Television The position of the image picked up by the camera on the reference plane (x-axis direction) y ': The position of the image picked up by the TV camera on the reference plane (y-axis direction) X ₀ : x of the laser light scanning rotation axis Coordinate Z ₀ : z coordinate of laser light scanning rotation axis a: distance between television camera and reference plane θ: laser slit light projection angle If the above equation (2) is modified, the height of the point hit by the laser slit light z (x ', y') is obtained by the following equation (3).

[0030]

(Equation 1)

The coordinates (x, y) on the three-dimensional coordinates of the point (x ', y') where the laser light is extracted on the image are given by the following equations (4) and (5). x = ｛1−z (x ′, y ′) / a｝ x ′ (4) y = ｛1−z (x ′, y ′) / a｝ y ′ (5)

As apparent from the above description, the three-dimensional coordinates (x, y) of the point where the laser slit light is detected at the coordinates (x ', y') on the image of the television camera 10 at the projection angle θ.
y, z) is obtained by the above equations (3), (4), and (5).
Here, the above equations (4) and (5) have been corrected for the perspective effect that the closer to the TV camera 10 the larger the closer to the TV camera 10 because the distance between the coil 3 and the TV camera 10 is finite. It is. It can be seen that accurate shape detection cannot be performed with a two-dimensional image obtained by simply processing a captured image, and it is necessary to perform correction.

FIGS. 5A, 5B and 5C show the optical system of FIG. 1 (TV camera 10, slit light scanning device 12).
FIG. 2 is a plan view, a front view, and an image in the field of view of the television camera 10 when the camera is placed on an overhead crane. As shown in FIG. 1A, the television camera 10 is moved clockwise in a direction
It is arranged in a direction rotated by 5 ° and its optical axis is positioned vertically downward. Further, the slit light scanning device 12 is located on the trolley 30 and the x of the television camera 10.
Installed on axis. Then, the direction of the generated laser slit light is adjusted so as to be parallel to the y-axis direction of the television camera 10. The coil 3 to be measured is placed parallel to the traversing direction or traveling direction of the overhead crane. Usually, in the yard, the coil 3 is arranged in either the traversing direction or the traveling direction of the overhead crane, and the arrangement direction is known by the system computer managing the yard.
It is possible to arrange. Therefore, in the present embodiment, the coil 3 captured by the television camera 10
Is inclined (rotated) by 45 ° in the visual field.

The slit light scanning device 12 generates laser slit light from the laser spot light, and scans the laser slit light within the visual field of the television camera 10 so as to cut the coil 3. The television camera 10 captures the state. The captured image is an image obtained by irradiating the coil 3 with the laser slit light at an angle of 45 degrees. The image synthesizing device 14 generates a synthesized image by the method described above. The shape calculation device 16 calculates the shape of the portion (light cutting line) hit by the laser slit light based on the composite image based on the above calculation formula. By performing calculations for each light cutting line, the TV camera 10
A plurality of cross-sectional shapes of the object within the measurement field of view can be obtained.

Next, the coil arithmetic unit 18 uses the cross-sectional shape data to identify the coil and the peripheral portion (the floor and the truck) from the difference in height, since the coil is higher than the floor and the truck. Then, only the shape data of the portion determined to be a coil is extracted. Further, from the extracted data on the cross-sectional shape of the coil, data on the projected shape in the radial and width directions of the coil is obtained in order to detect the position of the coil. Here, it is assumed that the projection is made on a plane perpendicular to the reference plane 1 in the radial direction of the coil.

FIG. 6 is an explanatory diagram for obtaining projection shape data of the radial projection and the width projection of the coil. 6, the number of laser slit lights and the light projection direction of the slit light scanning device 12 are different from those in FIG. 5 for simplicity of description. Here, the TV camera 1 which is a detection head
The shape of the coil 3 is projected in a direction rotated by an installation angle of 0 (45 °), that is, in a traversing direction and a traveling direction of the trolley 30. In the projection in the coil width direction, the average value of shape data in the coil width direction of each cross-sectional shape is obtained,
The value is used as data of the projection shape in the width direction. In the projection in the coil radial direction, the maximum value of the shape data in the coil radial direction of each cross-sectional shape is used as data of the radially projected shape.

FIG. 7 is a diagram showing a state in which specular reflection is applied when the properties of the coil 3 are specular. When the coil 3 has a mirror-like property, the regular reflection light of the laser slit light applied to the coil 3 may enter the television camera 10.
The case where the reflected light enters and the part where the reflected light enters vary depending on the arrangement conditions and the like, but under the same conditions, the part where the regular reflected light enters is the same. Here, a position where the reflected light enters the television camera 10 will be considered. There is no particular problem unless the position where the reflected light enters is near the region where the light to be the coil edge of the coil 3 enters. However, when specularly reflected light enters near the area where the light to be the coil edge enters, the light is strong and the light is spread and input, so the projected radial shape is also expanded, and the calculated coil is calculated. The width is
It may be wider than the actual coil width. Therefore, by performing the processing for removing such spread light before calculating the coil width or the like, the accuracy of position detection can be improved.

FIG. 8 is a diagram showing the relationship between the projection angle θ and the shape projected in the radial direction. Next, a method of removing an extra portion of the radial projection shape will be described. In the projection in the radial direction, the maximum value of the coordinates of the cross-sectional shape data at each point in the radial direction is set as the value of the projected shape data. Here, the point A of the projected shape is considered. When performing the processing of the projection shape, the maximum value of the coordinates of the cross-sectional shape data of a1, a2, a3, and a4 becomes the projection shape data at point A. Regarding the radial projection, the coil 3 sets the interval of the laser slit light so that the projection is always performed by a plurality of laser slit lights. Therefore, in FIG. When the data a1, a2, a3, and a4 are detected, the projection angles are θ5, θ6, and θ, respectively.
7, θ8.

Next, the point B of the projection shape will be considered. When performing the projection processing, the maximum value of the coordinates of each of the shape data b1, b2, and b3 is set as the projection data at the point B. According to the projection angle image signal, the sectional shape data b1, b2, b3
Are all θ5 when is detected. From this, the cross-sectional shape data calculated from the light spread by the reflected light (cross-sectional shape data calculated in the range of B ′) is recorded in the radial projection with the same projection angle image signal. It can be seen that it is. Therefore, an accurate coil width can be obtained by excluding a portion of the shape data calculated only with the same projection angle. Therefore, the coil operation device 18 removes such a portion based on the input cross-sectional shape data and the projection angle image signal.

FIG. 9 is a diagram showing a state after the influence of specular reflection light is removed. In the portion inside the coil width, the influence of the reflected light remains, but there is no effect on the calculation of the coil width.
After removing the effects of specular light, the coil width,
The width center position, diameter, and diameter center position are calculated.

FIG. 10 is a diagram showing the relationship between the projected shape of the coil width and the threshold level for width determination. Coil arithmetic unit 1
8 obtains a coil width direction position, a coil width, a coil radial direction center position, and a coil diameter from respective projection shape data obtained by projecting the cross-sectional shape in the coil width direction and the radial direction.
A certain threshold value is set for the radial direction of the coil, and FIG.
As shown in (2), from the radially projected projection shape data, points at the left and right ends of the portion equal to or larger than the threshold value are detected, and the points are recognized as the right edge and the left edge of the coil. The coil width and the width center position are obtained by the following equations (5) and (6), respectively. Coil width center position = (right edge + left edge) / 2 (5) Coil width = | right edge−left edge | (6)

Next, the data of the projection shape in the width direction will be described. In FIG. 6, laser slit light 41, 42,
At 43, for example, an average value at the illustrated points is obtained,
The average value is used as the coordinate value of a point in the projected shape in the coil width direction. Similarly, laser slit light 41, 42,
The average value of the other points 43 and 44 is also obtained, and the entire projected shape 45 in the coil width direction is obtained. In theory,
The resulting projected shape in the width direction is a semicircle.

In the coil width direction, since the projected coil shape becomes a semicircle, the center position and the diameter of the coil can be obtained by substituting the shape data into the equation of the circle. (X−c _x ) ² + (z−z _x ) ² = r ² ... (7) x, z: semicircular shape data c _x of the coil obtained by the projection, z _x: coil radially central position r: radius of the coil

Specifically, if there is projection shape data at three or more points in the coil width direction, the above equation (7) can be solved to obtain the center position and the like. Here, in order to effectively use the projection shape data in the coil width direction and improve the reliability of position detection, a plurality of combinations of three points are set for the projection shape data in the coil width direction. Numerical values that do not satisfy the rules are removed from the plurality of center positions obtained by the respective calculations, and then statistical processing is performed to obtain highly accurate and reliable coil diameters and diameter center positions.

As a method of setting and removing the prescribed values, a method of obtaining a distribution of measured values and removing points separated from a predetermined range by majority rule theory, or an average of all center positions obtained by point calculation. There is a method of deleting data of points set in advance in order of increasing distance from the value.
Such a process is naturally used also at the stage of obtaining the cross-sectional shape in the coil radial direction and for removing abnormal shape data from the obtained cross-sectional shape.

Further, a method of obtaining a true center position from a large number of calculated coil center positions includes a method of obtaining an average value of many points, and a method of dividing a distribution of many points into a mesh and taking the maximum value of the distribution. There is a method of obtaining the position, and the like.

The above description is of an example in which the arrangement direction of the coil 3 is known in advance.
Can be processed in the same manner even when the direction of is not known in advance. In this case, the direction of the coil 3 is temporarily determined, and then the projected shape in the coil width direction and the radial direction is obtained. Since the arrangement direction of the coil 3 can be determined from the obtained shape data, the arrangement direction of the coil 3 is compared with the provisionally determined arrangement direction of the coil. Ask for.

The overhead crane is controlled based on the coil width and the center position obtained by the coil position detecting device,
Carry the coil.

In this embodiment, as is apparent from the above description, the slit light scanning device 12 irradiates the coil 3 with the laser slit light by scanning the laser spot light two-dimensionally. When the light cutting line formed at that time is projected in the radial direction, the laser slit light is irradiated at intervals such that a plurality of light cutting lines are projected at any position of the coil 3.
The illuminated light cutting line is imaged by the television camera 10, and the image synthesizing device 14 synthesizes the luminance image level and the projection angle at that time by irradiating each laser slit light, and binarizes the image signal and the projection. An angle image signal is generated, and the shape calculation device 16 calculates three-dimensional cross-sectional shape data based on the binarized image signal and the projection angle image signal light. This cross-sectional shape data represents the position coordinates of the light section line. The coil calculating device 18 projects the cross-sectional shape in the radial direction, and calculates the coil width and the center position of the width. At this time, in the projection in the coil radial direction, only the shape created at the same light projection angle is removed, and then the coil width and the center position of the width are calculated. Also,
The sectional shape data is projected in the coil width direction, and the center position of the diameter and the size of the diameter are calculated. Therefore, even if the surface property of the coil 3 is mirror-like, the influence of the specular reflection light can be eliminated, and the coil width can be calculated accurately, so that a highly accurate coil position detecting device can be obtained. Further, the slit light scanning device 12 outputs a projection angle signal representing the projection angle θ of each laser slit light, which is simultaneously obtained based on the irradiation of the laser slit light, and the coil operation device 18 performs the projection in the radial direction. At this time, by irradiating a plurality of laser slit lights, a portion where a plurality of cross-sectional shape data exists is determined based on the projection angle θ, so that the accuracy can be more easily improved. When the slit light scanning device 12 irradiates a plurality of laser slit lights, the laser spot light, which is a point of the laser light, is two-dimensionally scanned and irradiated. Irradiation with slit light can also be performed. Further, according to the present invention, when projecting the three-dimensional cross-sectional shape data in the radial direction of the coil, the coil calculation means 18 projects the data on the surface perpendicular to the reference plane 1, so that the coil diameter is perpendicular to the reference plane. And projecting onto a plane parallel to a vertical line segment to the overhead crane, always including the part where the z-axis direction of the coil 3 is the largest (the part with the highest height). The accuracy of the calculation can be improved.

Embodiment 2 In the above-described embodiment, the description is limited to the coil position detecting device. However, the present invention is not limited to this, and can be applied to an object to be measured other than the coil.

[0051]

As described above, according to the present invention, when the laser beam projecting means looks at the coil in the radial direction, the portion where the brightness is changed by the irradiation of the plurality of laser slit beams at any position. Irradiates each laser slit light so that there exists, and when the coil calculating means projects the three-dimensional shape data extracted and determined in the coil radial direction in the coil radial direction, calculation is performed by irradiating a plurality of laser slit lights. Since the coil width and the center position in the width direction are calculated based on the portion where a plurality of pieces of three-dimensional shape data exist,
This can occur when the surface properties of the coil are mirror-like,
Since the three-dimensional shape data portion calculated by the specular reflection light of a certain laser slit light can be removed and the coil width can be calculated accurately, a highly accurate coil position detecting device can be obtained.

Further, according to the present invention, the laser beam projecting means outputs the beam projecting angle information indicating the beam projecting angle of each laser slit beam, which is simultaneously obtained based on the irradiation of the laser slit beam, and performs the coil calculation. The device, in radial projection,
Since a portion where a plurality of three-dimensional shape data is present is determined based on the projection angle information by irradiating a plurality of laser slit lights, a highly accurate coil position detecting device can be obtained more easily.

Further, according to the present invention, when irradiating a plurality of laser slit lights, the laser light projecting means is configured to two-dimensionally scan and irradiate a laser spot which is a point of the laser light. It is also possible to irradiate laser slit light according to the size of the coil.

According to the invention, when the coil calculating means projects the three-dimensional shape data in the radial direction of the coil,
Since the diameter of the coil is perpendicular and projected onto a plane parallel to the vertical line segment on the overhead crane, the highest part of the coil is always included, so the accuracy of calculating the width of the coil and the center position in the width direction is improved. Can be enhanced.

[Brief description of the drawings]

FIG. 1 is a configuration diagram for explaining a measurement principle of a coil measurement device of the present invention.

FIG. 2 is a diagram showing a configuration of a slit light scanning device 12.

FIG. 3 is a block diagram illustrating a configuration of the image composition device 14.

FIG. 4 is an explanatory diagram conceptually showing a calculation process of the image synthesizing device 14.

FIG. 5 is a plan view, a front view, and a view showing an image in the field of view of the television camera 10 when the optical system of FIG. 1 is arranged on an overhead crane.

FIG. 6 is an explanatory diagram for obtaining projection shape data of a radial projection and a width projection of a coil.

FIG. 7 is a diagram showing a state in which specular reflection has occurred when the properties of the coil 3 are mirror-like properties.

FIG. 8 is a diagram illustrating a relationship between a projection angle θ and a projection shape in a radial direction.

FIG. 9 is a diagram illustrating a state after removing the influence of specular reflection light.

FIG. 10 is a diagram illustrating a relationship between a projected shape of a coil width and a threshold level for width determination.

FIG. 11 is a diagram showing a positional relationship between a coil for irradiating a laser spot light and a television camera.

FIG. 12 is a diagram illustrating a screen on which an imaging process has been performed.

[Explanation of symbols]

 Reference Signs List 10 TV camera 12 Slit light scanning device 14 Image synthesis device 16 Shape calculation device 18 Coil calculation device

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Mitsuaki Uesugi 1-2-1, Marunouchi, Chiyoda-ku, Tokyo F-term (reference) 2F065 AA04 AA07 AA17 AA24 AA26 AA53 BB06 BB25 CC00 FF04 FF26 GG06 GG12 HH05 JJ03 JJ26 LL13 MM16 QQ04 QQ24 QQ25 RR02 SS02 UU01 UU05 5F072 AB13 HH02 MM11 MM17 YY11

Claims (4)

[Claims] 1. A laser beam projecting means attached to an overhead crane for transporting a coil and irradiating the coil with a plurality of linear laser slit lights; and an image attached to the overhead crane and having the coil as a subject. An image synthesizing unit that processes an image captured by the imaging unit, determines and extracts a portion whose brightness has changed due to the irradiation of each of the laser slit lights, and creates a processed image; Shape calculation means for calculating three-dimensional shape data of the portion where the brightness has changed based on the processed image; and, among the three-dimensional shape data calculated by the shape calculation means, three-dimensional shape data of the coil portion Judge and extract,
The extracted three-dimensional shape data is projected in the radial direction of the coil to calculate at least the width of the coil and the center position of the width, and the extracted three-dimensional shape data is projected in the width direction of the coil. A coil calculating means for calculating at least a diameter of the coil and a center position of the diameter, wherein the laser beam projecting means includes a plurality of laser slit lights at any position when the coil is viewed in the radial direction. Irradiating each of the laser slit lights so that there is a portion in which the brightness has changed due to the irradiation of the coil. The coil calculating means determines the coil portion and extracts the three-dimensional shape data extracted in the coil radial direction. When projected on the basis of the portion where there are a plurality of three-dimensional shape data calculated by irradiation of a plurality of laser slit light,
A coil position detecting device for calculating at least the width of the coil and the center position in the width direction. 2. The laser beam projecting means outputs a beam projecting angle signal representing a beam projecting angle of each of the laser slit beams. The coil position detecting device according to claim 1, wherein the determination of the portion where the dimensional shape data exists is performed based on the light projection angle signal. 3. The coil position detecting device according to claim 1, wherein the laser beam projecting unit irradiates the plurality of laser slit beams by two-dimensionally scanning a laser spot beam. 4. The coil calculating means, when projecting the three-dimensional shape data in a radial direction of the coil, sets the diameter of the coil as a perpendicular line and projects the surface on a plane parallel to a line segment perpendicular to the overhead crane. The coil position detecting device according to any one of claims 1, 2 and 3, wherein: