KR101764640B1 - image-based portable surface crack detecting apparatus - Google Patents

image-based portable surface crack detecting apparatus Download PDF

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KR101764640B1
KR101764640B1 KR1020150186425A KR20150186425A KR101764640B1 KR 101764640 B1 KR101764640 B1 KR 101764640B1 KR 1020150186425 A KR1020150186425 A KR 1020150186425A KR 20150186425 A KR20150186425 A KR 20150186425A KR 101764640 B1 KR101764640 B1 KR 101764640B1
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crack
image
main body
scale member
present
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KR20170076902A (en
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윤혁진
조현우
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한국철도기술연구원
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B11/00—Measuring arrangements characterised by the use of optical techniques
    • G01B11/14—Measuring arrangements characterised by the use of optical techniques for measuring distance or clearance between spaced objects or spaced apertures
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B11/00—Measuring arrangements characterised by the use of optical techniques
    • G01B11/24—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures
    • G01B11/255—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures for measuring radius of curvature
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B3/00—Measuring instruments characterised by the use of mechanical techniques
    • G01B3/002—Details
    • G01B3/004—Scales; Graduations
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/84—Systems specially adapted for particular applications
    • G01N21/88—Investigating the presence of flaws or contamination
    • G01N21/8806—Specially adapted optical and illumination features
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T7/00—Image analysis
    • G06T7/0002—Inspection of images, e.g. flaw detection
    • G06T7/0004—Industrial image inspection

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  • Engineering & Computer Science (AREA)
  • Immunology (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Pathology (AREA)
  • Health & Medical Sciences (AREA)
  • Quality & Reliability (AREA)
  • Computer Vision & Pattern Recognition (AREA)
  • Theoretical Computer Science (AREA)
  • Length Measuring Devices By Optical Means (AREA)
  • Investigating Materials By The Use Of Optical Means Adapted For Particular Applications (AREA)

Abstract

The present invention relates to an image-based portable surface crack measuring apparatus, and more particularly, to a crack detecting apparatus capable of measuring crack size quickly by measuring a crack size by photographing a crack generated on a concrete surface with a digital camera, In addition, the present invention relates to an image-based portable surface crack measuring apparatus capable of precisely measuring a crack on a curved surface such as a column.
According to an aspect of the present invention, there is provided a surface crack measuring apparatus comprising: a body; a portable device fixed to the body, the body having a camera; a pair of first supporting legs provided at a lower portion of the body; And a scale member provided between the first support legs. The scale member is made of a transparent material, and has a mark of a predetermined size attached thereto at a predetermined interval.

Description

[0001] The present invention relates to an image-based portable surface crack measuring apparatus,

The present invention relates to an image-based portable surface crack measuring apparatus, and more particularly, to a crack detecting apparatus capable of measuring crack size quickly by measuring a crack size by photographing a crack generated on a concrete surface with a digital camera, In addition, the present invention relates to an image-based portable surface crack measuring apparatus capable of precisely measuring a crack on a curved surface such as a column.

In general, the maintenance plan for the current type 1 facility under the Special Law on Facilities Safety Management includes the precise inspections carried out at least once every three years and the one type facilities that have passed 10 years after completion There is precision safety diagnosis carried out above.

The overhaul is a check to ensure that the planned status of the facility is accurately determined by the planned periodic inspection, that the change from the original or previously recorded status is confirmed, and that the structure still meets the current usage requirements.

The precision safety diagnosis is a close inspection including a measurement with a precise visual inspection and measurement equipment performed in order to detect defective parts which can not be easily found through an inspection process.

In the maintenance of industrial facilities through the above-mentioned precision inspection and precise safety diagnosis, inspection of cracks is an inspection target for important damage. For this purpose, in the past, the inspector carried a field of view, a crack width measurer, or a crack sensor, and approached the field to measure the crack width in an analog manner and then write it in the field. Therefore, the objective judgment of the inspector was intervened to secure systematic and objective data And there is a disadvantage in that it takes much time and manpower because the crack width measurer or the crack width measurement is required to visually confirm cracks.

Therefore, there are many difficulties in field work, and there is a problem that different results may be recorded in the field or report due to the subjective judgment of the expert (expert) or non-expert (non-expert) .

In addition, in order to measure long-term behavior characteristics such as crack propagation, conventionally, there is a method in which a tester periodically measures the variation amount of a crack tip in the field after installing a crack tip, or a data logger is installed near a crack gauge Or periodically the data logger was carried by the tester. However, periodic measurement by installing a crack tip or attaching a crack gauge can not effectively prevent sudden damage. The installation of a crack gauge and the installation of a data logger nearby have a disadvantage in that the facility investment cost is very expensive.

In order to solve such a problem, Korean Unexamined Patent Application Publication No. 10-2005-0018773 as shown in FIGS. 1 and 2 has been proposed. The camera captures an image of a camera, a lighting unit, To allow a quantitative conversion of the crack width to be possible; A grip portion 202 that is easy to carry and has a shooting switch and a screen display portion; An image acquisition switch 203; A memory unit 209 and a CPU arithmetic unit 210 for storage of the acquired image, image processing, and calculation of a crack width; A magnifying glass 205 for magnifying and reducing the magnification by a predetermined magnification so as to facilitate measurement of fine cracks; An image acquisition camera 206 for acquiring an image; An illumination unit 207 for facilitating measurement even in a dark place such as a tunnel and providing light for securing a resolution of photographed image data; And a screen display unit 208 for displaying the calculated crack width in digital values.

However, the technique disclosed in Korean Patent Publication No. 10-2005-0018773 has an advantage that cracks can be measured more accurately and quickly because the cracks are measured through the image. However, when the surface is not flat and rounded, There is a problem that the size of the crack can not be accurately measured.

SUMMARY OF THE INVENTION The present invention has been conceived to solve the problems described above. An object of the present invention is to fix a portable device having a camera on a main body and to measure the size of a crack formed on the concrete surface by photographing the surface of the concrete. A scale member is provided between a pair of first support legs provided at a lower portion of the scale member, and a mark having a size set at a predetermined interval is attached to the scale member to be photographed like a crack formed on the concrete surface, Based surface crack measuring apparatus capable of accurately measuring the size of a crack through a relationship with a pixel.

It is another object of the present invention to provide a scale member that is provided between a pair of first supports so as to be in contact with a concrete surface, wherein the scale member is formed of a well-bending material, It is possible to attach the scale member to the concrete surface having a curvature like a column without changing the length of the scale member and to accurately measure the curvature according to the interval of the mark and the mark size which are already set, Based portable surface crack measuring apparatus capable of accurately measuring a surface-based portable surface crack.

SUMMARY OF THE INVENTION [0006]

An image-based portable surface crack measuring apparatus comprising: a main body; a portable device fixed to the main body, the main body including a camera; a pair of first supporting legs provided at a lower portion of the main body; And a scale member formed on the base member.

Here, the scale member is made of a transparent material, and marks of a set size are attached at regular intervals.

At this time, an elastic member is provided at one or both ends of the scale member, and is connected to the lower end of the first support leg.

The main body is provided with a fixing member for fixing the portable device.

Here, the main body is provided with a length adjusting member for adjusting the length of the fixing member.

Meanwhile, a second support leg may be further provided on the lower center of the main body.

In this case, the first and second support legs are adjustable in length.

In the portable device, the curvature and spatial resolution of the concrete surface are measured through the distance between the actual mark and the measured mark.

According to the present invention having the above-described structure, a portable device having a camera is fixed to a main body, and a size of a crack formed on the surface of the concrete is measured by photographing the surface of the concrete. And a mark having a size set at a predetermined interval is attached to the scale member so as to be photographed like cracks formed on the surface of the concrete so as to accurately measure the size of the crack Can be measured.

According to the present invention, the scale member is provided between the pair of first supports so as to be in contact with the surface of the concrete, and the scale member is formed of a well-bending material, and elastic members capable of changing the length are provided at both ends of the scale member It is possible to accurately measure the curvature according to the interval of the marks and the mark size, and also to measure the crack size of the curved surface accurately. There is an effect to be able to do.

1 is a perspective view of a conventional crack measuring apparatus.
2 is a block diagram of a conventional crack measuring apparatus.
3 is a perspective view of an image-based portable surface crack measuring apparatus according to the present invention.
4 is an exploded perspective view of an image-based portable surface crack measuring apparatus according to the present invention.
FIG. 5 is a bottom view of a scale member of an image-based portable surface crack measurement apparatus according to the present invention.
FIG. 6 is a state view of the image-based portable surface crack measuring apparatus according to the present invention in a state where a scale member is attached to a column.
FIG. 7 is a front view showing a state where a scale member of a video-based portable surface crack measurement apparatus according to the present invention is attached to a column.
FIG. 8 is a state diagram showing an example of an image of a surface taken by an image-based portable surface crack measuring apparatus according to the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The same reference numerals are used for the same constituent elements in the drawings and redundant explanations for the same constituent elements are omitted. It is to be understood that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

FIG. 3 is a perspective view of an image-based portable surface crack measuring apparatus according to the present invention, FIG. 4 is an exploded perspective view of an image-based portable surface crack measuring apparatus according to the present invention, FIG. 6 is a state view showing a state where a scale member of the image-based portable surface crack measuring apparatus according to the present invention is attached to a column, FIG. 7 is a view showing a state of a surface- FIG. 8 is a state view showing an example of an image of a surface taken by the image-based portable surface crack measuring apparatus according to the present invention.

The present invention relates to an image-based portable surface crack measuring apparatus, and as shown in FIGS. 3 and 4, comprises a main body 300 and a portable device (not shown) fixed to the main body 300 A pair of first support legs 330 installed at a lower portion of the main body 300 and a scale member 350 provided between the first support legs 330.

At this time, the main body 300 and the first support legs 330 are connected to each other by a connection part 370.

The main body 300 is formed in a U shape and an opening 305 is formed at the center of the main body 300. The camera of the portable device 400 is connected to the lower portion of the main body 300 through the opening 305 of the main body 300, So that the cracks on the concrete surface and the scale member 350 are simultaneously photographed.

At this time, the main body 300 may be formed as a square frame having an opening 305 formed therein.

The scale member 350 connects the end portions of the pair of first support legs 330 and may have a rectangular shape. However, if the first support legs 300 can be connected to each other, It may be done in shape.

Here, the scale member 350 is made of a transparent material, and the mark 360 is attached to the scale member 350 at regular intervals. The mark 360 is also formed to have a predetermined size.

At this time, an elastic member 352 is provided on both sides or one end of the scale member 350. A contact portion 332 is provided at the lower end of the first support leg 330, An installation groove 334 into which the elastic member 352 is inserted is formed.

The lower surface of the first support leg 330 and the lower surface of the scale member 350 are located on the same plane so that when the first support leg 330 is brought into contact with the concrete surface to be measured, Is brought into complete contact with the surface.

6, when the scale member 350 is placed in the longitudinal direction in the direction in which the curvature is formed, the scale member 350 (see FIG. 6) The elastic member 352 is made of an elastic material whose length is adjustable and is long enough to warp the scale member 350 so that the elastic force of the elastic member 352 The length is kept constant.

6, the spacing between the marks 360 becomes narrower toward both ends of the scale member 350 as shown in FIG. 7, when photographing a column or the like on which the surface is formed to be rounded.

Thus, it is possible to calculate the curvature of the concrete surface through the distance between the actual marks 360 and the distance between the measured marks 360, and thereby to measure the spatial resolution of the image, It is possible to accurately measure the size of cracks formed in the cracks.

On the other hand, a method of measuring the width of the cracks formed on the rounded surface is as follows. As shown in FIG. 8, the lengths of the crack widths w1 and w2 can be obtained by the trigonometric function as follows.

Figure 112015127017480-pat00001

If a1 is occupied by a1 p and b1 p is occupied by a captured image, a1 p = 4 and b1 p = 5. In order to measure the length of the actual crack, the measured value of the pixel unit in the image should be converted into the actual distance in mm. For conversion, we need to know the spatial resolution, which is the actual length of a pixel in an image. The spatial resolution of the image is expressed in mm / pixel.

The spatial resolution can be obtained by using a mark that already knows the actual size in the image. The spatial resolution (mm / pixel) can be obtained by dividing the actual size of the mark by the pixel occupied by the mark in the image.

If the actual lengths of a1 and b1 are denoted by a1 d , b1 d and w1 d , the actual crack width is

Figure 112015127017480-pat00002
.

To calculate a d and b d , we need to know the spatial resolution of each pixel, but when we take a surface, the spatial resolution changes along the curved surface. Therefore, the length and width of the cracks formed on the curved surface can not be obtained with only one mark.

In order to obtain the crack width formed on the curved surface, the intervals of the marks arranged at equal intervals can be used. The mark formed on the scale member is curved along the curved surface when it is brought into close contact with the curved surface, and is spaced apart from the center of the image.

By dividing the distance d1 d between the marks that already know the distances by the number d1 p of pixels occupied by the image d1, it is possible to obtain the spatial resolution considering the curvature. The spatial resolutions a1 g and a2 g of a1 and a2 can be obtained as follows.

Figure 112015127017480-pat00003

Figure 112015127017480-pat00004

When a cylindrical column of concrete columns is photographed, it is assumed that the spatial resolution in the vertical direction is almost the same, and b1 g and b2 g are the actual length of the mark and the number of pixels occupied by the mark in the image. Where b1 g and b2 g are the spatial resolutions of b1 and b2.

The formula for finding the actual length of the crack (w1 d )

Figure 112015127017480-pat00005
Is expressed as follows.

Figure 112015127017480-pat00006

The above equation can be used to measure the actual crack length and w2 d can be obtained in the same way. In addition to the cracks on the concrete surface, the steel pipe can be applied to other members.

The main body 300 is provided with a fixing member 320 for fixing the portable device 400 and the fixing member 320 is adjustable in length by the length adjusting member 310.

Thus, it is possible to measure the cracks by fixing the portable device 400 of various sizes to the main body 300.

A second support leg 340 is further provided at the lower center of the main body 300. A contact portion 342 is formed at the lower end of the second support leg 340 to measure cracks in the concrete or the surface. When the first and second support legs 330 and 340 are brought into contact with the surface for the first and second support legs 330 and 340, the surface is prevented from being damaged.

At this time, the body 300 and the second support leg 340 are connected by a connection part (not shown).

The first and second support legs 330 and 340 are formed to be adjustable in length by a sliding method, so that the first and second support legs 330 and 340 can be appropriately adjusted in length according to the situation of the field.

Here, the configuration for adjusting the lengths of the first and second support legs 330 and 340 and the configuration of the length adjuster 310 are already known, and therefore, a detailed description thereof will be omitted.

While the present invention has been described in connection with certain exemplary embodiments, it is to be understood that the scope of the present invention is not limited to the disclosed embodiments, It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

The present invention relates to an image-based portable surface crack measuring apparatus, and more particularly, to a crack detecting apparatus capable of measuring crack size quickly by measuring a crack size by photographing a crack generated on a concrete surface with a digital camera, In addition, the present invention relates to an image-based portable surface crack measuring apparatus capable of precisely measuring a crack on a curved surface such as a column.

300: main body 310: length adjusting portion
320: fixing member 330: first supporting leg
340: second support leg 350: scale member
360: Mark 400: Mobile device
500: Column

Claims (8)

An image-based portable surface crack measuring apparatus comprising:
A main body,
A portable device fixed to the main body and having a camera;
A pair of first support legs provided at a lower portion of the main body,
And a scale member provided between the first support legs,
Wherein the scale member is made of a transparent material,
Wherein the elastic member is provided at one or both ends of the scale member and connected to the lower end of the first support leg.
delete delete The method according to claim 1,
Wherein the main body is provided with a fixing member for fixing the portable device.
5. The method of claim 4,
Wherein the main body is provided with a length adjusting member for adjusting the length of the fixing member.
The method according to claim 1,
And a second support leg is further provided at a lower center of the main body.
The method according to claim 6,
Wherein the first and second support legs are adjustable in length.
The method according to claim 1,
Wherein the portable device measures the curvature and spatial resolution of the concrete surface through the distance of the actual mark and the distance of the measured mark.
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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101972768B1 (en) 2019-01-10 2019-04-29 주식회사 다산컨설턴트 Crack Length Measuring Device for Structural Safety Inspection
KR20190087179A (en) 2018-01-16 2019-07-24 주식회사 지오멕스소프트 A measuring method for detecting cracks on the structure surface and the recording medium thereof
KR102016531B1 (en) 2019-01-03 2019-08-30 (주)한국종합시설안전 Crack Length Measuring Device for Safety Diagnosis
KR102069122B1 (en) 2019-09-04 2020-01-22 주식회사 수성엔지니어링 Crack Length Measuring Device for Structural Safety Check
KR20220045502A (en) 2020-10-05 2022-04-12 주식회사 한국건설방재연구원 Portable electronic crack measurement device
KR102582597B1 (en) 2022-11-16 2023-09-26 (주)천일이엔에스 Crack Length Measuring Device for Structural Safety Check

Families Citing this family (1)

* Cited by examiner, † Cited by third party
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KR101876887B1 (en) * 2017-04-12 2018-07-10 (주)지구환경전문가그룹 Apparatus and method for measurement control of crack using smartphone

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JP2011191282A (en) 2010-03-12 2011-09-29 Hironobu Horiuchi Displacement measuring method using moire fringe
KR101316451B1 (en) * 2012-10-18 2013-10-08 현대건설주식회사 Concrete surface crack detecting apparatus, detecting method, smart phone and public computer
KR101439282B1 (en) * 2014-06-23 2014-09-12 (주)정우구조엔지니어링 Crack measuring apparatus of structure for combining into smart phone using fixture
JP2017049152A (en) 2015-09-03 2017-03-09 株式会社 日立産業制御ソリューションズ Crack width measuring system

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Publication number Priority date Publication date Assignee Title
JP2011191282A (en) 2010-03-12 2011-09-29 Hironobu Horiuchi Displacement measuring method using moire fringe
KR101316451B1 (en) * 2012-10-18 2013-10-08 현대건설주식회사 Concrete surface crack detecting apparatus, detecting method, smart phone and public computer
KR101439282B1 (en) * 2014-06-23 2014-09-12 (주)정우구조엔지니어링 Crack measuring apparatus of structure for combining into smart phone using fixture
JP2017049152A (en) 2015-09-03 2017-03-09 株式会社 日立産業制御ソリューションズ Crack width measuring system

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20190087179A (en) 2018-01-16 2019-07-24 주식회사 지오멕스소프트 A measuring method for detecting cracks on the structure surface and the recording medium thereof
KR102016531B1 (en) 2019-01-03 2019-08-30 (주)한국종합시설안전 Crack Length Measuring Device for Safety Diagnosis
KR101972768B1 (en) 2019-01-10 2019-04-29 주식회사 다산컨설턴트 Crack Length Measuring Device for Structural Safety Inspection
KR102069122B1 (en) 2019-09-04 2020-01-22 주식회사 수성엔지니어링 Crack Length Measuring Device for Structural Safety Check
KR20220045502A (en) 2020-10-05 2022-04-12 주식회사 한국건설방재연구원 Portable electronic crack measurement device
KR102582597B1 (en) 2022-11-16 2023-09-26 (주)천일이엔에스 Crack Length Measuring Device for Structural Safety Check

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