JP2002228419A - Dimension measuring apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dimension measuring apparatus whose constitution is comparatively simple. SOLUTION: The dimension measuring apparatus is provided with an imaging part 1 used to photograph a specimen, a plurality of spot light sources 1d by which spotlike beams of light L are irradiated in parallel toward the front at prescribed intervals from the imaging part 1 so as to be displayed inside the photographing screen of the imaging part 1 and an image display means 4 used to display the photographing screen.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a size measuring device for measuring the size of a measurement object from a photographed image.

[0002]

2. Description of the Related Art When measuring the size of an object to be measured such as a foreign matter, which is present in a pipe or the like that cannot be directly viewed by an operator, a small CCD camera attached to the end of a cable or the like is used. Is being inserted into a pipeline, and the dimensions of a measurement object such as the foreign substance are measured based on a captured image in the pipeline captured by the imaging device. In such a dimension measurement method based on a captured image, for example, a method of measuring the distance between an imaging device and a measurement target based on parallax when capturing the measurement target from different directions and measuring the dimension of the measurement target Also, a special linear shadow is projected on the measurement target, and the distance between the imaging device and the measurement target is measured based on where the linear shadow is located on the shooting screen, and the dimension of the measurement target is determined. How to measure,
Etc. are known.

[0003]

However, the above-mentioned prior art has a problem that the configuration of the whole apparatus is complicated, and as a result, the handling is complicated and the cost is increased. That is, in each of the above-described prior arts, the position of parallax or a linear shadow is detected by performing digital image processing on a shooting screen, and the distance between the imaging device and the measurement target is calculated based on the detection result. Since the actual dimensions of the measurement object projected on the photographing screen are calculated based on the calculation results, a calculation device for performing such various calculations is required.

In addition, the configuration of an optical system, that is, an imaging device, is complicated in order to photograph an object to be measured from different directions or to project a special linear shadow on the object to be measured.
As a result, the handling is complicated and the cost is increased, and the failure rate is increased.

The present invention has been made in view of the above-mentioned problems, and has as its object to provide a dimension measuring apparatus having a relatively simple configuration.

[0006]

In order to achieve the above object, according to the present invention, as a first means relating to a dimension measuring device, an image pickup section for photographing an object to be measured and a photographing screen of the image pickup section are provided. A means comprising a plurality of spot light sources for projecting a spot light beam in parallel forward from the imaging unit at a predetermined interval so as to be projected, and image display means for projecting the photographing screen is adopted.

[0007] As a second means relating to the dimension measuring apparatus, in the first means, the spot light source employs means for irradiating a spot-shaped laser beam to the object to be measured as a spot-shaped light beam.

[0008] As a third means relating to the dimension measuring device,
In the first or second means, means for adding an illumination light source to the imaging unit is employed.

As fourth means relating to the dimension measuring device,
In any one of the first to third means, the image pickup unit includes a small CCD camera, the small CCD camera is provided at a front end of a long signal cable, and an image display unit is provided at a rear end. I do.

As a fifth means relating to the dimension measuring device,
In the fourth means, a means is adopted in which the cross-sectional shape of the imaging section is cylindrical.

As a sixth means relating to the dimension measuring device,
In the fourth means, a means is employed in which the cross-sectional shape of the imaging section is substantially crescent-shaped.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a dimension measuring device according to the present invention will be described with reference to the drawings. In the present embodiment, the present invention is applied to an inspection in a pipeline of a power pipe buried underground.

FIG. 1 is a system configuration diagram showing the overall configuration of the present embodiment. In this figure, reference numeral 1 denotes an imaging unit,
2 is a signal cable, 3 is a drum, and 4 is a monitor (image display means). The imaging unit 1 is attached to a distal end of the signal cable 2, and the monitor 4 is connected to a rear end of the signal cable 2. As shown in the drawing, the imaging unit 1 is sequentially sent into an electric power pipe by an operator operating the signal cable 2 and photographs the state of each part in the electric power pipe.

An image photographed by the image pickup unit 1 is transmitted as a video signal to a monitor 4 via a signal cable 2.
And displayed on the monitor 4 as an image pickup screen. In addition, the drum 3 winds the long signal cable 2 corresponding to the length of the electric power pipe, and is provided on the ground.

As shown in FIG. 2, the imaging section 1 comprises a main body 1a, a small CCD camera 1b, illumination light sources 1c, 1c, a pair of laser spot light sources 1d, 1d, and the like. The main body 1a houses a small CCD camera 1b and illumination light sources 1c, 1c, and has a substantially crescent-shaped cross section orthogonal to the axial direction of the signal cable 2. Further, the distal end face 1e of the main body 1a is orthogonal to the axial direction of the signal cable 2 similarly to the above-mentioned cross section, and is therefore formed in a substantially crescent shape. The imaging unit 1 having such a main body shape is sequentially fed into the power pipe along a gap between the cylindrical power pipe and a power cable inserted into the power pipe.

The small CCD camera 1b is set so that the photographing direction is directed from the front end face 1e to the front, and uses the photographed image in the power pipe as a video signal as a signal cable 2.
Is supplied to the monitor 4 via. Lighting sources 1c, 1c
Indicates that the illumination direction is the tip surface 1 as in the case of the small CCD camera 1b.
e, and a pair is provided on both sides of the small CCD camera 1b. By providing the illumination light sources 1c, 1c, the small CCD camera 1b can reliably capture an image in the power pipe in a dark power pipe.

A pair of laser spot light sources 1d, 1d are provided on the distal end face 1e and further outside the illumination light sources 1c, 1c at symmetrical positions with respect to the small CCD camera 1b. These laser spot light sources 1d, 1d
Is a small CCD camera 1 such that strip-shaped spot lights L, L are projected on the photographing screen of the small CCD camera 1b.
Spot light L, L (spot-like laser beam) is irradiated in parallel forward at a predetermined interval D from b.

Next, the measurement of the dimension of the object to be measured using the present dimension measuring apparatus thus configured will be described in detail with reference to FIG.

FIG. 3A is an imaging screen G1 showing a state in which the size of the foreign matter W in the power pipe as the object to be measured is measured. In this case, the worker irradiates the spot light L, L to the foreign matter W by adjusting the feed amount (length) of the signal cable 2 to the power pipe. By the irradiation of the spot lights L, L, two light spots P, P are formed on the foreign matter W. In this state, the imaging screen G1
The distance between the light spots P, P projected on the spot is the same as the distance D between the spot lights L, L. The width D can be easily measured by comparing the width of the foreign matter W with the distance D as a reference dimension. Can be.

On the other hand, FIG. 3B is an imaging screen G2 showing the measurement state of the dimension d of the step W 'at the joint of the power pipe as the measurement object. In this embodiment,
Since the operator sends the imaging unit 1 into the power pipe by manually operating the signal cable 2, the imaging position of the imaging unit 1 in the power pipe cannot be freely changed.
The step size d can be easily measured by relative comparison with the distance D between the light spots P, P in the imaging screen G2.

As described above, according to the present embodiment, the distance D between the light spots P, P in the imaging screens G1, G2 and the foreign matter W
The size of the foreign matter W or the step W ′ in the power pipe can be measured with a very simple configuration only by relative comparison with the step or the step W ′. It does not require digital image processing or complicated arithmetic processing unlike the prior art.

Note that the present invention is not limited to the above embodiment, and for example, the following modifications can be considered. (1) Instead of the above embodiment, as shown in FIG.
It is conceivable to set the cross-sectional shape of a 'to a cylindrical shape. In the case of the imaging unit 1A, a circular tip surface 1g is used.
, A small CCD camera 1b is arranged at the center thereof, and a plurality of (six in total) illumination light sources 1c,...

(2) In the above embodiment, one pair of laser spot light sources 1d, 1d are provided on the left and right sides of the small CCD camera 1b. Further, two pairs of laser spot light sources 1d, 1d may be provided not only on the left and right but also on the upper and lower sides.

(3) Further, in the above embodiment, the present invention is applied to the inspection of the inside of the electric power piping, but the present invention is not applicable only to such inspection of the electric power piping. . The present invention can be applied to dimension measurement of various measurement objects.

[0025]

As described above, according to the present invention,
An imaging unit that captures an object to be measured, a plurality of spot light sources that irradiate parallel spot-like rays forward from the imaging unit at predetermined intervals so as to be displayed in the imaging screen of the imaging unit, and an image that projects the imaging screen Display means,
The dimensions of the object to be measured can be measured very easily only by comparing the interval between the spot-shaped light beams in the image screen and the object to be measured.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram showing an overall configuration of an embodiment of the present invention.

FIG. 2 is a perspective view illustrating a configuration of an imaging unit according to the embodiment of the present invention.

FIGS. 3A and 3B are a plan view and a plan view showing an imaging screen for foreign matter in a pipeline and an imaging screen of a pipeline step in an embodiment of the present invention. FIGS.

FIG. 4 is a perspective view showing a modification of the imaging unit according to the embodiment of the present invention.

[Description of Signs] 1 ... Imaging unit, 1a ... Main body, 1b ... Small CCD camera, 1c ... Light source for illumination, 1d ... Laser spot light source, 2 ... Signal cable, 3 ... Drum, 4 ... ... Monitor (image display means), L ... Spot light, P ... Light spot

Claims (6)

[Claims] An imaging unit (1) for imaging a measurement object, and a spot-like light beam (L) forward from the imaging unit (1) at a predetermined interval so as to be displayed on an imaging screen of the imaging unit (1). ,
L) A plurality of spot light sources (1d, 1d) for parallel irradiation
And an image display means (4) for projecting the photographing screen. 2. The dimension measuring apparatus according to claim 1, wherein the spot light source (1d, 1d) irradiates a spot-shaped laser beam to the object to be measured as a spot-shaped beam (L, L). 3. The dimension measuring device according to claim 1, wherein an illumination light source is added to the imaging unit. 4. An imaging unit (1) includes a small CCD camera (1).
4. A small-sized CCD camera (1a) is provided at an end of a long signal cable (2), and an image display means (4) is provided at a rear end, respectively. The dimension measuring device according to any one of the above. 5. The dimension measuring device according to claim 4, wherein the cross-sectional shape of the imaging section is cylindrical. 6. The dimension measuring device according to claim 4, wherein the cross-sectional shape of the imaging section is substantially crescent-shaped.