JPH11248422A - Device for detecting segment position - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve safety and workability in segment assembly work, by detecting segment position with high precision related to a segment position detecting device. SOLUTION: A reflection seal 11 is pasted on a suspension piece P of a segment S, the reflection seal 11 is irradiated with a ring lighting 13, a camera 12 images the reflection light from the reflection seal 11, an image processing device 14 obtains the position of a gravity center of the suspension piece P based on the picture imaged by the camera 12, and a control device 15 drives and controls a holding mechanism 10 based on the position of gravity center of the suspension piece P obtained by the image processing device 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a segment position detecting device for detecting a grip position of a segment carried into an existing tunnel.

[0002]

2. Description of the Related Art When constructing a tunnel, segments are assembled on the inner wall surface of an existing tunnel by an erector device while excavating the tunnel by a tunnel excavator. The segment is carried into the existing tunnel by the transport mechanism, and the carried segment is transported to the erector device by the gripping mechanism.

FIG. 6 is a schematic diagram showing a segment conveying mechanism and a gripping mechanism, FIG. 7 is a schematic diagram of a conventional segment position detecting device, FIG. 8 is a control block showing a conventional segment position detecting device image processing device, and FIG. FIG. 10 shows an outline of an image taken by the camera, and FIG. 10 is a graph showing the density of the image taken by the camera.

As shown in FIG. 6, a transport mechanism 101 comprises a rail 102 laid in an existing tunnel and a transport vehicle (not shown) movable along the rail 102. A segment S is mounted on the transport vehicle. Can be carried into the existing tunnel. The gripping mechanism 103 has a fork shape and is movable in a three-dimensional direction by a support mechanism (not shown), and can grip the hanging piece P fixed to the center of gravity of the segment S.

Therefore, the segment S to which the hanging piece P is fixed is mounted on the transport mechanism 101 and carried into the existing tunnel, and the gripping mechanism 103 is hooked on the hanging piece P of the segment S mounted on the transport mechanism 101. And hold it, and move to a predetermined position. In this case, the segment S is stopped at a predetermined position by the transport mechanism 101, and the gripping mechanism 103 grips the suspended hanging piece P. However, the segment S is a heavy object, and the rail 102 of the transport mechanism 101 is bent by the weight, the position of the hanging piece P is shifted, and the gripping mechanism 103 may not be able to grip.

Therefore, conventionally, the position of the hanging piece P of the segment S is detected by the segment position detecting device, and then the gripping mechanism 103 grips the hanging piece P. This conventional segment position detecting device includes a laser slit light source 201, a camera 202, an image processing device 203, and a control device 204, as shown in FIG.

[0007] The laser slit light source 201 irradiates slit light F to the upper surface of the hanging piece P so as to be orthogonal to the transport direction of the segment S. The camera 202 captures an image of the periphery of the hanging piece P from above.

As shown in FIG. 8, the image processing device 203 includes an A / D converter 205, an image memory 206, and a binarizing device 20.
7 and right end measuring device 208 and left end measuring device 209 and center position calculator 2
10 and have. The A / D converter 205 converts an image signal of the periphery of the hanging piece P captured by the camera 202 into a digital value. The image memory 206 stores an image converted into a digital value. The binarizing device 207 binarizes the image stored in the image memory 206.
The right end measuring device 208 and the left end measuring device 209 are for obtaining the right end position and the left end position of the binarized image. The center position calculator 210 calculates the center position of the binarized image from the right end position and the left end position of the image.

Further, the control device 204 controls the position of the gripping mechanism 103 based on the position of the hanging piece P of the segment S obtained by the image processing device 203.

[0010] Therefore, as shown in FIG.
Is fixed to the transport mechanism 101 and carried into the existing tunnel. The slit light F is emitted from the laser slit light source 201 to the upper surface of the hanging piece P of the segment S, and the camera 202 captures an image of the hanging piece P from above, and as shown in FIG. capturing an image T representing the slit light image F _a. In this case, the length of the slit light F is larger than the diameter of the suspension piece P, and is a length that allows for the amount of displacement of the segment S. The field of view taken by the camera 202 also has a size that allows for the amount of displacement of the segment S.

An image (image signal) T captured by the camera 202 is output to an image processing device 203 and is converted into a digital value by an A / D converter 202 as shown in FIG.
It is temporarily stored in the image memory 206. The binarizing device 207 has a segment S previously photographed in accordance with the surrounding environmental illuminance.
And a threshold value for identifying each density of the upper surface image of the hanging piece P, and the image stored in the image memory 206 is binarized based on the threshold value. That is, as shown in FIG. 10, the image T captured by the camera 202 has a difference in the density in the length direction of the slit light F, and the threshold value is set to C ₁ (or C ₂ ) so that the upper surface of the hanging piece P only the slit light image F _a is at H (Yes concentration), the other area is converted into the binarized image and L (no concentration).

The binarized image of the area H is obtained from the right end measuring device 208 and the left end measuring device 209, and the coordinates of the right end position and the left end position are obtained. The center position calculator 210 calculates the right end position and the left end position of the image. The center position of the binarized image of the area H is obtained by calculating the average value of each coordinate of. That is,
As shown in FIGS. 9 and 10, lifting the upper surface of the piece P is a circle, since the slit light image F _a of the hanging piece P upper surface becomes strings hanging piece bisector of the chord is a circle P
Will pass through the center position O _a of the right and left directions, can obtain this center position O _a. Then, the image processing device
203 (center position calculator 210) outputs the center position O _a hanging piece P of segment S to the controller 204, the controller 20
4 the gripping mechanism 103 to position control on the basis of the center position O _a of the hanging piece P, and grasping the piece P suspended by moving to a predetermined position.

[0013]

[SUMMARY OF THE INVENTION In conventional segment position detecting apparatus described above, by irradiating the slit light F hanging piece P upper surface of the segment S, the camera 202 captures the image T of the slit light image F _a from above, identifies the region H of the slit light image F _a by binarizing based on the image processing apparatus 203 by the image T the threshold C ₁ (or C _2), the mean value from the coordinates of the right end position and a left end position by calculating, seeking the center position O _a hanging piece P.

In this case, the image processing device 203 uses the suspended piece P based on the density of the image T captured by the camera 202.
While identifying the region H of the slit light image F _a of the upper surface, when the upper surface of the hanging piece P is dirty, there is the identification error of the region H noise is generated occurs.
That is, as shown in FIG. 10, when there is no dirt on the upper surface of the hanging piece P can properly determine the area H of the slit light image F _a becomes the binarized image as shown by the solid line. However, if there is dirt on the upper surface of the suspending piece P, the reflectance is reduced and noise N as shown by a two-dot chain line is generated, and the density of a part of the binarized image is reduced and the slit light image F _a the region H becomes to determine apologizing and H _1. Then, the image processing device 20
3 the right instrument 209 error occurs in the coordinates of the right end position, the center position calculator 210 will center position of the hanging piece P is determined to O _b, it can not be determined the correct center position O _a, the gripping mechanism There is a problem that 103 cannot grip the hanging piece P.

[0015] As shown in FIG.
The threshold value C ₁ which is set at 7 by the lower threshold C _2, although it is possible to find the correct center position O _a of the hanging piece P to eliminate the influence of slight noise N, piece hanging segment S P And the boundary of the density region is ambiguous, an error occurs in the identification, and the center position of the hanging piece P cannot be obtained with high accuracy.

The present invention solves such a problem, and provides a segment position detecting device which improves the safety and workability of a segment assembling operation by detecting the position of a segment with high accuracy. The purpose is to do.

[0017]

According to a first aspect of the present invention, there is provided a segment position detecting device for suspending a segment conveyed to a predetermined position so that the segment can be grasped by a grasping mechanism. In the segment position detection device for detecting the position of the portion, a reflector provided in the hanging portion, a camera that captures an image of the periphery of the hanging portion including the reflector, and having the same optical axis as the camera, Ring illumination that irradiates the periphery of the hanging portion including a reflector, an image processing device that determines the position of the hanging portion based on an image captured by the camera, and a position of the hanging portion that is determined by the image processing device. And a control device for driving and controlling the gripping mechanism.

The segment position detecting device according to the second aspect of the present invention is characterized in that the reflector is a reflective seal.

According to a third aspect of the present invention, there is provided a segment position detecting device for detecting a position of a hanging portion of a segment so that the segment conveyed to a predetermined position can be gripped by a gripping mechanism. A heating device that heats the hanging portion, an infrared camera that captures an image of the periphery of the hanging portion, an image processing device that determines the position of the hanging portion based on an image captured by the infrared camera, and an image processing device that determines the position of the hanging portion. A control device for controlling the driving of the gripping mechanism based on the position of the hanging portion.

[0020]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a schematic diagram of a segment position detecting device according to a first embodiment of the present invention, FIG. 2 is a control block showing an image processing device of the segment position detecting device of the present embodiment, and FIG. An outline is shown.

As shown in FIG. 1, the segment S whose position is detected by the segment position detecting device of the present embodiment is:
The segment S is transported into the existing tunnel by a transport mechanism (not shown). A hanging piece P composed of a disc and a pin is fixed to the center of gravity of the upper surface of the segment S, and the fork-shaped gripping mechanism 10 can be gripped. Has become.

The segment position detecting device according to the present embodiment
A reflection seal 11 attached as a reflector to the upper surface of the hanging piece P of the segment S, a camera 12 for imaging the periphery of the hanging piece P including the reflecting seal 11, and an optical axis identical to that of the camera 12. A ring illumination 13 for irradiating the periphery of the hanging piece P including the reflective seal 11;
2 has an image processing device 14 for determining the position of the hanging piece P based on the image captured by the image processing device 2, and a control device 15 for driving and controlling the gripping mechanism 10 based on the position of the hanging piece P determined by the image processing device 14. doing.

The reflection seal 11 is a circular sticking object,
It is attached to the upper surface such that the center coincides with the center of the hanging piece P. Note that a fluorescent paint may be applied instead of the reflective seal 11. The camera 12 is mounted downward above the segment S, and captures an image having a field of view around the hanging piece P including the reflective seal 11, that is, the entire area where the hanging piece P may pass when the segment S moves. can do. The ring illumination 13 is attached around the camera 12 and has an optical axis that coincides with the optical axis of the camera 12 so as to be able to illuminate the field of view imaged by the camera 12. Therefore, light emitted from the ring illumination 13 is reflected by the reflection seal 11 and is reflected by the camera 12.
Can be imaged with high brightness.

As shown in FIG. 2, the image processing device 14 includes an A / D converter 21, an image memory 22, a binarizing device 23, an area measuring device 24, a center of gravity measuring device 25, and a height correcting device 26. And a center-of-gravity position correcting device 27. The A / D converter 21 converts an image signal of the periphery of the hanging piece P captured by the camera 12 into a digital value. The image memory 22 temporarily stores an image converted into a digital value. The binarizing device 23 binarizes the image stored in the image memory 22. The area measuring device 24 calculates the area of the hanging piece P (reflective seal 11) from the binarized image, and the center of gravity measuring device 25 calculates the hanging piece P from the binarized image and the area of the hanging piece P (reflective seal 11). The position of the center of gravity of P is obtained. The height correcting device 26 corrects the height position of the hanging piece P from the area of the hanging piece P (reflective seal 11), and the center-of-gravity position correcting device 27 calculates the center-of-gravity position of the hanging piece P and the height correction value. Is used to correct the position of the center of gravity.

Further, the control device 15 controls the position of the gripping mechanism 10 based on the position of the hanging piece P of the segment S obtained by the image processing device 14.

Therefore, as shown in FIG.
Is mounted on the transport mechanism and carried into the existing tunnel. When the upper surface of the hanging piece P of the segment S is irradiated from the ring light 13, the reflected light reflected by the reflective seal 11 is Input to the camera 12 with high brightness. The camera 12 confirms passage of the segment S based on a signal from the transport mechanism or a signal from a position sensor (not shown), captures an image of the periphery of the hanging piece P from above, and as shown in FIG. An image T of the upper surface of P is captured.

In the image (image signal) T captured by the camera 12, only the image portion 11a of the reflective seal 11 has high brightness, and the other portions have low brightness. In this case, the difference in brightness between the reflective seal 11 and the other parts can be enlarged by painting the upper surface of the hanging piece P black before attaching the reflective seal 11. Further, by narrowing down the exposure amount of the camera 12, the brightness of the image can be adjusted.

The image (image signal) T captured by the camera 12 is output to the image processing device 14 and converted into a digital value by the A / D converter 21 as shown in FIG. Is stored temporarily. In the binarizing device 23, a threshold value for identifying each luminance of the image portion 11a of the reflective seal 11 photographed in accordance with the surrounding environmental luminance and each luminance of the other portions is set in advance and stored in the image memory 22. The resulting image is binarized based on this threshold. That is, in the image T captured by the camera 12, the area of only the image portion 11a of the reflective seal 11 is H, and the other areas are converted to L and the binarized image.

Then, the area measuring device 24 obtains the area A from the binarized image by measuring the area H, that is, the number of pixels of the reflective seal 11 of the hanging piece P. in this case,
When the hanging piece P is displaced in the height direction due to the bending of the transport mechanism, the area A in the camera image T changes.
That is, when the hanging piece P is lowered and the distance from the camera 12 to the hanging piece P (reflective seal 11) is increased, the area A is reduced, and the hanging piece P is raised and the area from the camera 12 to the hanging piece P (reflective seal 11) is close. If this happens, the area A will increase. However, since the area of the reflective seal 11 is constant, the length of the camera image T in one pixel space can be calculated from the relationship between the actual area of the reflective seal 11 and the area A captured by the camera 12.

The area A measured in the camera image T can be obtained from the radius r on the camera image T and the following equation 1 since the reflective seal 11 is circular.

[0032]

(Equation 1)

Here, assuming that the actual radius of the reflective seal 11 is R, the length L of one pixel of the camera image T in the space can be obtained by the following equation (2).

[0034]

(Equation 2)

Since the actual area of the reflective seal 11 and the amount of height deviation due to the bending of the transport mechanism can be known in advance, the range of change in the area A of the reflective seal 11 on the camera image T can be predicted. It is. Therefore, the center of gravity of the extracted region H is determined by setting the allowable range of the change of the area A of the reflection seal 11 on the camera image T. In other words, at the time when the area measurement instrument 24 determine the area A of the reflective label 11, the center of gravity meter 25 obtains the gravity center position i _g in the lateral direction of the reflective label 11 formed of a region H from the following equation 3. Here, i is the horizontal coordinate of each pixel.

[0036]

(Equation 3)

The height correction device 26 determines the horizontal center of gravity of the reflective seal 11 when the hanging piece P passes without deviation as _ig0, and the deviation Δi as measured.
Can be obtained by the following equation (4).

[0038]

(Equation 4)

The center-of-gravity position correcting device 27 is
Center of gravity position X in which the height of thread P has been corrected _gIs calculated by the following equation (5).
Can be

[0040]

(Equation 5)

[0041] Thereafter, the image processing apparatus 14 (the center-of-gravity position correcting device 27) outputs the center-of-gravity position X _g of the hanging piece P of segment S to the controller 15, the controller 15 to the center-of-gravity position X _g of the hanging piece P The position of the gripping mechanism 10 is controlled based on this, and the gripping mechanism 10 is moved to a predetermined position to grip the hanging piece P.

As described above, in the segment position detecting device of the present embodiment, the reflective seal 11 is attached to the hanging piece P of the segment S, and the reflective seal 11 is irradiated by the ring illumination 13, and the camera 12 Reflective seal 11
The image processing device 14 obtains the position of the center of gravity X _g of the hanging piece P based on the image T captured by the camera 12, and the control device 15 determines the position of the hanging piece P obtained by the image processing device 14. gripping mechanism 10 on the basis of the center-of-gravity position X _g
Drive control. Accordingly, the camera 12 is securely capturing the reflected light of the reflective label 11, the image processing apparatus 14 can determine the center-of-gravity position X _g of the pieces P suspended from the image T of the camera 12 with high precision, the gripping mechanism 10 The hanging piece P is securely gripped to prevent loss or the like.
In addition, the reliability of the measurement data is improved by performing the test of the region H from the relationship between the actual area of the reflective seal 11 and the area A captured by the camera 12.

FIG. 4 shows an outline of a segment position detecting device according to a second embodiment of the present invention, and FIG. 5 shows an outline of an image captured by a camera. Note that members having the same functions as those described in the above-described embodiment are denoted by the same reference numerals, and redundant description will be omitted.

The segment position detecting device according to the present embodiment
As shown in FIG. 4, a heating device 3 for heating the hanging piece P
1, an infrared camera 32 for imaging the periphery of the hanging piece P, an image processing device 33 for obtaining the position of the hanging piece P based on the image captured by the infrared camera 32, and a hanging And a control device 34 for controlling the driving of the gripping mechanism 10 based on the position of the piece P.

The heating device 31 heats the upper surface of the hanging piece P of the segment S conveyed by the conveying mechanism, and may be any device that can heat metal, such as a sheet heater, an induction heating device, or a burner. In this case, since the hanging piece P is made of metal, it has good heat transferability and can be heated in a relatively short time, so that a large-scale heating device is unnecessary.
Further, since the segment S is made of concrete, the heat transfer property is not good, and the segment S is not heated even if the hanging piece P is heated. And this heating device 31
When the suspended piece P of the conveyed segment S comes directly below the infrared camera 33 during heating of the suspended piece P by the above, there is only a temperature difference between the upper surface of the suspended piece P and the upper surface of the segment S. What is necessary is just to heat to about 40-50 degreeC which has little influence on a human body.

The infrared camera 32 is mounted downward above the segment S, and captures an image having a field of view around the hanging piece P, that is, the entire region where the hanging piece P may pass when the segment S moves. be able to. The infrared camera 32 can capture infrared light emitted from the subject, that is, heat as an image. Note that the image processing device 33 and the control device 34 are substantially the same as the image processing device 14 and the control device 15 of the above-described first embodiment, and thus detailed description is omitted.

Accordingly, as shown in FIG. 4, the segment S transported by the transport mechanism heats the suspended piece P to about 40 to 50 ° C. by the heating device 31, and the infrared camera 32 captures an image of the periphery of the suspended piece P. Then, infrared rays emitted from the heated hanging piece P, that is, heat, are captured as an image. As shown in FIG. 5, the image (image signal) T captured by the infrared camera 32 has a high density because the image portion Pa of the hanging piece P has a high temperature, and the other portions have a low temperature. The density becomes darker.

The image (image signal) T captured by the infrared camera 32 is output to the image processing device 33, and the same processing as that of the image processing device 14 described above is performed.
_g can be obtained. Thereafter, the image processing device 33 outputs the center of gravity position X _g of the hanging piece P of the segment S to the control device 34, and the control device 34 controls the position of the gripping mechanism 10 based on the center of gravity position X _g of the hanging piece P, It moves to a predetermined position and grips the hanging piece P.

As described above, in the segment position detecting device of this embodiment, the segment S is
Is heated, and the infrared camera 32 captures an image of the periphery of the heated hanging piece P, and the image processing device 33
Obtains the position of the center of gravity X _g of the hanging piece P based on the image T captured by the infrared camera 32, and the control device 34 controls the gripping mechanism 10 based on the position of the center of gravity X _g of the hanging piece P obtained by the image processing device 33. The drive is controlled. Therefore, the infrared camera 32 determines the hanging piece P based on the temperature.
Reliably captured, the image processing apparatus 33 can determine the center-of-gravity position X _g of the pieces P suspended from the image T of the infrared camera 32 with high accuracy, the gripping mechanism 10 is securely gripping the hanging piece P deficiency Is prevented. Further, since the image processing device 33 can recognize only the hanging piece P from the high-temperature portion of the camera image T, there is no need to set a threshold value in advance as in the binarization device 23 of the first embodiment, and the threshold value in the preliminary test is not necessary. Confirmation is not required. Furthermore, since the hanging piece P is recognized using the thermal image, even if there is work lighting around the work piece, there is no disturbance and the work environment is less restricted.

[0050]

As described above in detail in the embodiment, according to the segment position detecting device of the first aspect of the present invention, the reflector is provided on the segment hanging portion, and the periphery of the hanging portion is illuminated by ring illumination. The camera images the periphery of the suspension including the reflector, the image processing device obtains the position of the suspension based on the image captured by the camera, and the control device determines the position of the suspension determined by the image processing device. Since the gripping mechanism is driven and controlled based on the camera, the camera reliably captures the reflected light of the reflector, and the image processing apparatus can accurately determine the position of the suspension from the camera image. The hanging portion can be securely grasped to prevent loss and the like, and the safety and workability of the segment assembling operation can be improved.

According to the segment position detecting device of the second aspect of the present invention, since the reflector is a reflection seal, the reflector can be easily formed, and the workability can be improved.

Further, according to the segment position detecting device of the third aspect of the present invention, a heating device for heating the hanging portion of the segment is provided, and the infrared camera takes an image of the periphery of the hanging portion,
The image processing device obtains the position of the hanging portion based on the image captured by the infrared camera, and the control device drives and controls the gripping mechanism based on the position of the hanging portion obtained by the image processing device. The suspension is reliably imaged based on the temperature, and the image processing apparatus can accurately determine the position of the suspension from the camera image. The gripping mechanism securely grips the suspension to prevent loss and the like. It is possible to improve the safety and workability of the segment assembling work.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a segment position detecting device according to a first embodiment of the present invention.

FIG. 2 is a control block diagram illustrating an image processing device of the segment position detection device according to the present embodiment.

FIG. 3 is a schematic diagram of an image captured by a camera.

FIG. 4 is a schematic diagram of a segment position detecting device according to a second embodiment of the present invention.

FIG. 5 is a schematic view of an image captured by a camera.

FIG. 6 is a schematic diagram illustrating a segment transport mechanism and a gripping mechanism.

FIG. 7 is a schematic diagram of a conventional segment position detecting device.

FIG. 8 is a control block diagram illustrating an image processing device of a conventional segment position detecting device.

FIG. 9 is a schematic view of an image captured by a camera.

FIG. 10 is a graph showing the density of an image captured by a camera.

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 gripping mechanism 11 reflective seal (reflector) 12 camera 13 ring illumination 14 image processing device 15 control device 21 A / D converter 22 image memory 23 binarization device 24 area measurement device 25 center of gravity measurement device 26 height correction device 27 Center of gravity position correction device 31 Heating device 32 Infrared camera 33 Image processing device 34 Control device S segment P Hanging piece

Claims (3)

[Claims] 1. A segment position detecting device for detecting a position of a hanging portion of a segment so that the segment conveyed to a predetermined position can be gripped by a gripping mechanism, wherein a reflector provided on the hanging portion; A camera that images the periphery of the suspension including the body, a ring illumination that has the same optical axis as the camera and irradiates the periphery of the suspension including the reflector, and based on an image captured by the camera. A segment position detecting device, comprising: an image processing device that determines the position of the hanging portion by using the control device; and a control device that drives and controls the gripping mechanism based on the position of the hanging portion determined by the image processing device. 2. The segment position detecting device according to claim 1, wherein said reflector is a reflective seal. 3. A segment position detecting device for detecting a position of a hanging portion of a segment so that the segment conveyed to a predetermined position can be gripped by a gripping mechanism, wherein the heating device heats the hanging portion, and the hanging portion. An infrared camera that captures an image of the surroundings, and an image processing device that determines the position of the suspension unit based on an image captured by the infrared camera,
A control device for controlling the driving of the gripping mechanism based on the position of the hanging portion determined by the image processing device.