JPH11257953A - Tunnel wall surface observing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten image sensing time and image processing time of a tunnel wall surface, obtain a continuous image free from joint, and enable three- dimensional observation of an external appearance state of the tunnel wall surface. SOLUTION: A tunnel wall surface is image-sensed with three line cameras 11, image data of analog amount corresponding to the images are outputted in time series and converted to digital data via the respective three system A/D converters 12. The digital data are stored in the respective three system image storage devices 13 in such a manner that the three lines are simultaneous, line by line. When a specified amount of image data are stored in the three system image storage devices 13, these image data are recorded in a digital recorder 15 and transferred to an image processing part 18, in which the transferred image data of each line are arranged in the order of image sensing and developed in continuous images in three directions. A display part 19 displays the continuous images in the three directions on the respective display units. The continuous images in the three directions are combined and a three- dimensional image having a depth is displayed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tunnel wall observation device used for inspection of deformation in a tunnel such as a railway or an automobile road, and for investigation of geology in a horizontal shaft.

[0002]

Heretofore, in the investigation of the deformation of a tunnel, it has been general to mount a mechanical scanner or a television camera on a traveling vehicle and photograph the tunnel wall. In the case of a television camera, 60 images are switched per second in the NTSC system, so that each image is displayed about every 16.7 ms. For this reason, when photographing while traveling in a tunnel, it is necessary to reduce the traveling speed according to the resolution in order to increase the resolution of the image. For example, if the image resolution is 1
mm or less, the running speed needs to be 60 mm per second, and if converted to hourly speed, it must be 216 m / hour or less, which is quite slow.

[0003] In addition, the image of the television camera is 1 / 60th
Since the images are intermittent every second, a large amount of pixel data is rearranged when joining the captured images of the tunnel wall surface to develop a continuous image, which requires a huge amount of image processing time.

[0004] Further, in the image of the television camera, a difference in color tone or a shift occurs between a central portion and a peripheral portion due to chromatic aberration and spherical aberration of a lens. When the images are joined, an unnatural joint is formed at a joint portion. There is a problem of appearing.

Furthermore, since a television camera can capture an image only from one direction at a time, it has been difficult to three-dimensionally analyze the state of the tunnel wall surface by combining images having different viewing angles.

Accordingly, the present invention reduces the photographing time and image processing time by photographing the tunnel wall surface using a line camera instead of a conventional television camera, and obtains a continuous image without a seam. An object of the present invention is to capture images having different viewing angles at a time by using the images and combine the images so that the appearance state of the tunnel wall surface can be three-dimensionally observed.

[0007]

In order to achieve the above object, the present invention is configured as follows.

That is, an illumination device for illuminating a tunnel wall surface, a line camera for photographing one-dimensional image data of the tunnel wall surface illuminated by the illumination device with different viewing angles at a time, and the line camera is mounted to travel in a tunnel. Traveling device, recording means for respectively recording the one-dimensional image data having different viewing angles of the tunnel wall surface photographed by the line camera, and the one-dimensional image data having the different viewing angles of the tunnel wall surface recorded by the recording means are arranged in order of photographing. And a continuous image developing means for developing a continuous image.

[0009]

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

FIG. 1 shows an overall configuration diagram of a tunnel wall surface observation device embodying the present invention. The tunnel wall observation device
A photographing device 1 for photographing the tunnel wall surface, an illuminating device 2 for illuminating the tunnel wall surface, a traveling vehicle 3 running in the tunnel with these devices mounted thereon, A tilt sensor 4 for outputting a signal and a traveling vehicle 3
Of the axle 3a is detected by a pulse signal.

FIG. 2 is a block diagram of a photographing device of the tunnel wall surface observation device embodying the present invention. The photographing device 1
A three-line camera 11 that simultaneously captures three lines of one-dimensional image data, three A / D converters 12 that convert image signals output from the three-line cameras 11 into digital signals, and an A / D converter 12 , Each of which stores image data converted into a digital signal.
And a display 1 for displaying the contents of the image memory 13 respectively
4, a digital recorder 15 for recording image data as digital data when the amount of image data stored in the three systems of image memories 13 reaches a predetermined amount, and inputting signals from the tilt sensor 4 and the rotary encoder 5 Line camera 1
1, a controller 16 for controlling the A / D converter 12, the image memory 13, and the digital recorder 15 in a predetermined procedure
And an image processing unit 18 that takes in the image data recorded in the digital recorder 15 into the memory 17 and develops it into a continuous image.
And a display unit 1 for displaying a continuous image developed in the memory 17
9.

As shown in FIG. 3, the three-line camera 11 arranges three photoelectric conversion elements a, b, and c in the movement direction.
Attach a wide-angle lens with an angle of view of 180 ° or more to shoot three-dimensional one-dimensional images of a tunnel roof arch in three directions simultaneously. As the photoelectric conversion elements a, b, and c, use is made of a line sensor which is a signal transfer type image sensor in which light receiving elements such as CCDs are arranged in a straight line. This three-line camera 11
The density color information on the imaging line read by is output in a time-series manner for each line as a one-dimensional image.

The tunnel wall observing device embodying the present invention has the above-described configuration, with the optical axis of the three-line camera 11 facing the wall surface of the tunnel, traveling the traveling vehicle 3 in the length direction of the tunnel, and moving the tunnel wall surface. Shoot.

The line sensors a, b, and c incorporated in the three-line camera 11 output image data of an analog amount corresponding to the image in chronological order. The output image data is converted into digital data through three A / D converters 12, and the pulse of the rotary encoder 5 is used as a trigger to simultaneously output three lines to three lines of image memory 13 simultaneously. Is stored. At this time, 3
The pulse count value indicating the shooting position of the line camera 11 and the digitally converted output signal of the tilt sensor 4 are also recorded at the same time. When a predetermined amount of image data is stored in the three systems of image memories 13, these image data are recorded as digital data in the digital recorder 15.

The image data recorded on the digital recorder 15 is transferred to an image processing section 18. In the image processing unit 18,
The transferred image data for each line is arranged in the order of photographing, the starting point of the image data for each line is corrected according to the inclination angle output by the inclination sensor 4, and the distortion and displacement of the image are corrected. Each is developed into a continuous image. The display unit 19 displays the continuous images in the three directions on a display device, and displays the shooting position of the three-line camera 11 obtained from the pulse count value on a scale beside the screen. As described above, the state of the tunnel wall viewed from three directions can be observed in detail through a continuous image, and at the same time, the position of the image can be accurately known.

If the same image is photographed from different viewing angles by moving the three-line camera 11, a stereoscopic image with a large depth can be displayed. That is, as shown in FIG. 4, first, the line sensor a at the left end of the three-line camera 11
Captures the line A on the tunnel wall surface, and then, when the three-line camera 11 moves a predetermined distance, the line sensor c at the right end captures the same line A. When the line A on the tunnel wall surface is photographed by moving the three-line camera 11 in this manner, the images photographed by the line sensors a and c are images for the left and right eyes having binocular parallax.

A continuous image is created by arranging the images taken by the line sensor a at the left end and the line sensor c at the right end of the three-line camera 11 in the order in which they were taken, as shown in FIG.
The left and right images a and c having parallax are displayed. At this time, the display addresses of the images a and c are adjusted so that the line A is displayed at the same position on the two screens. By separately presenting the continuous images a and c having this parallax to the left and right eyes,
A space with depth before and after the display surface can be reproduced.

In order to obtain left and right parallax images by moving the three-line camera 11, it is necessary to display the left and right images with the moving direction being horizontal. That is, as shown in FIG. 5, a line A orthogonal to the moving direction of the three-line camera 11
Is displayed, the direction of the image is set such that the line A is a vertical line with respect to the left and right images.

In the case of the three-line camera 11, three recognizable points are formed on the digital image. When the corresponding points are calculated based on the position of the three-line camera 11, the focal length, and the angle of the optical axis, a tunnel is obtained. The three-dimensional coordinates of the wall surface can be calculated. By recording these three-dimensional coordinates in a computer and performing various processing, it is possible to analyze the appearance of the tunnel wall surface in three-dimensional detail.

[0020]

As described above, the tunnel wall surface observation apparatus of the present invention uses a line camera to photograph a tunnel wall surface at a speed that cannot be followed by a conventional television camera, so that the photographing time can be greatly reduced. Can be. On the other hand, since the image data captured by the line camera is output in chronological order, it is not necessary to rearrange a huge amount of pixel data, and the image processing is greatly accelerated. Further, a continuous image can be obtained without a seam portion becoming unnatural as in a television camera. Furthermore, by photographing images with different viewing angles at once using a line camera, the appearance of the tunnel wall surface can be three-dimensionally analyzed by combining these images.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a tunnel wall surface observation device embodying the present invention.

FIG. 2 is a block diagram of a photographing device of the tunnel wall surface observation device embodying the present invention.

FIG. 3 is a schematic explanatory diagram of a three-line camera.

FIG. 4 is an explanatory diagram of an angle of an optical axis of a three-line camera capable of stereoscopic viewing.

FIG. 5 is an explanatory diagram of a display position of a line A in left and right parallax images.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Imaging device 2 Illumination device 3 Traveling vehicle 4 Tilt sensor 5 Rotary encoder 11 3 Line camera 12 A / D converter 13 Image memory 14 Display 15 Digital recorder 16 Controller 17 Memory 18 Image processing unit 19 Display unit

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI G02B 23/24 G02B 23/24 C H04N 7/18 H04N 7/18 U

Claims (1)

[Claims] 1. An illumination device for illuminating a tunnel wall surface, a line camera for photographing one-dimensional image data of the tunnel wall surface illuminated by the illumination device with different viewing angles at a time, and running in the tunnel with the line camera mounted. A traveling device, recording means for recording the one-dimensional image data having different viewing angles of the tunnel wall taken by the line camera, and one-dimensional image data having different viewing angles on the tunnel wall recorded by the recording means arranged in the order of photographing. A tunnel image observing device comprising: a continuous image developing means for developing a continuous image.