KR100942379B1 - Crack detection apparatus and method of box culvert for electric power transmission using three-dimension laser scanner - Google Patents

Abstract

PURPOSE: A crack detection device and method of box culvert for electric power transmission using a three-dimensional laser scanner are provided to reduce the time for exploring for oil and to improve the accuracy of the deformity discovery. CONSTITUTION: A crack detection device and method of box culvert for electric power transmission using a three-dimensional laser scanner(30) comprises an optical scanner(32), and an image processing device(40). The laser scanner collects and outputs 3D video data about a wall and ceiling of the electric power conduit pipe and the laser scanner. The optical scanner comprises a beam projector and a photo diode. The optical scanner collects and outputs the 3D video data. The image processing device compares the saved two dimensional monoscopic image and new two dimension monoscopic image and detects the defect from the electric power conduit pipe.

Description

Crack Detection Apparatus and Method of Box Culvert for Electric Power Transmission Using Three-Dimension Laser Scanner}

The present invention relates to the field of power sphere defect detection using a three-dimensional laser scanner, and more particularly, to scan the interior of the power sphere with a three-dimensional laser scanner and then analyze the image data to determine whether a defect such as a crack has occurred. The present invention relates to an apparatus and method for detecting power sphere defects using a laser scanner.

In general, transmission and distribution lines are installed over long distances to supply electric power from power plants to consumers. Previously, transmission and distribution lines were installed in the air with high pylons or telephone poles, but recently, when power transmission and distribution lines were installed in the basement because power towers or telephone poles interfere with the aesthetics of the city and interfere with the construction of roads and buildings. Is increasing a lot.

However, in the case of electric power tools that are constructed underground using concrete, deterioration such as cracks, leaks, sinking, and hole displacement caused by external force occurs in terms of durability.

Conventionally, defects (such as cracks, leaks, sinking, and displacement of holes due to external forces) of electric power tools are visually observed or confirmed using strain gauges.

In the case of visual inspection, there is a possibility of missing a minute defect, and the variation of the result is large depending on the ability of the inspector, and in the case of using a strain gauge, there is a problem that it takes a lot of time and money to install, measure, and analyze. .

The present invention has been made in view of the above, and by using a three-dimensional laser scanner to scan the inner surface of the power bulb and analyze the scanned image data to determine whether a defect occurs, it is quick and accurate to detect the defect of the power bulb It is an object of the present invention to provide an apparatus and method for detecting a power sphere defect using a three-dimensional laser scanner.

In accordance with an aspect of the present invention, there is provided a power sphere defect detecting apparatus using a three-dimensional laser scanner, and the power sphere defect detecting unit using the three-dimensional laser scanner collects and outputs three-dimensional image data on the wall and ceiling of the power sphere. Laser scanners; And an image processing apparatus for converting the collected 3D image data into 2D image data using depth information, wherein the image processing apparatus includes a previously collected and stored 2D planar image and a newly generated 2D planar image. In contrast, the defect of the power tool is detected.

The power tool defect detector using the 3D laser scanner may further include an optical scanner including a beam projector on one side and a light receiver on the other side, and collecting and outputting 2D and 3D images.

The image processing apparatus may include an image collecting unit collecting images from the laser scanner and an optical scanner, an image storing unit storing images collected by the image collecting unit, and images collected by the image collecting unit. An image converter for converting a 3D image stored in the unit into a 2D image, a frequency converter for performing a frequency conversion on the 2D image converted by the image converter, and converting the data into a frequency domain data, and the frequency conversion A filtering unit for separating high frequency components from the image data converted from the data into the frequency domain data, a differential for generating a linear differential image of the depth information to remove linear inclination, and a final generated through the respective components. And an image output unit for displaying 2D image data on a display. Can be.

A base frame configured to be movable by installing a wheel at a lower end of the power tool defect probe using the 3D laser scanner; And it may further include a support that is installed to the height adjustment to the base frame.

The power tool defect inspection device using the three-dimensional laser scanner may be installed on one side of the support and may further include a digital camera for capturing an image of the inner surface of the power tool.

In accordance with another aspect of the present invention, there is provided a power sphere defect detection method using a three-dimensional laser scanner for detecting a defect inside a power sphere, and the power sphere defect detection method using the three-dimensional laser scanner includes an image of a wall and a ceiling of a power sphere. Providing a scanning device including a laser scanner or an optical scanner for collecting and outputting data, and an image processing apparatus for converting the collected 3D image data into 2D image data using depth information; Collecting image data by scanning the wall surface and the ceiling of the power tool using the laser scanner or the optical scanner; Processing the collected image data; And detecting a defect in the power sphere from the processed image data.

The processing of the image data may include converting a 3D image into a 2D image among the collected image data, converting the converted 2D image into data of a frequency domain by performing a frequency conversion on the converted 2D image, Separating the high frequency components from the image data converted into the data in the frequency domain, generating a second derivative image of the depth information, eliminating linear inclination, and outputting the final image data passed through the step to the display It may include the step.

According to an apparatus and method for detecting a power sphere defect using a three-dimensional laser scanner according to the present invention, after collecting three-dimensional image data using a laser scanner and processing the collected image data, a defect in the power sphere is detected and thus required for exploration. It is possible to minimize the time it takes, and accurate detection of the defect of the power bulb is possible.

In addition, according to the apparatus for detecting power sphere defects using the three-dimensional laser scanner and the method of the present invention, it is possible to further check the inspection result by the laser scanner using a digital camera, so that more accurate detection is possible.

Hereinafter, the same reference numerals will be described in detail with reference to the accompanying drawings, with reference to the same components preferred embodiments of the present invention. The terms or words used in the specification and claims are not to be construed as being limited to conventional or dictionary meanings, but should be construed as meanings and concepts corresponding to the technical matters of the present invention.

The embodiments described in the specification and the configuration shown in the drawings are preferred embodiments of the present invention, and do not represent all of the technical idea of the present invention, various equivalents and modifications that can be substituted for them at the time of the present application are There may be.

1 is a view showing a power sphere defect probe using a three-dimensional laser scanner according to an embodiment of the present invention.

Referring to Figure 1, the power sphere defect detection apparatus 100 using a three-dimensional laser scanner according to an embodiment of the present invention is the base frame 10, the base frame (10) is configured to be movable by installing a wheel at the bottom And a support 20, an image processing apparatus 40, and a laser scanner 30 installed on the support 20, the height of which can be adjusted to 10.

The base frame 10 may be configured to include a dolly or the like moving along a track. The support 20 may be composed of a tripod (for example, a tripod of the camera, etc.) capable of stable support with three-point support. Dolly and tripods are generally well known and widely used and detailed descriptions thereof will be omitted.

The power tool defect detecting apparatus 100 may install an optical scanner 32 in addition to the laser scanner 30 and / or replace the upper portion of the support 20.

The laser scanner 30 may be configured to include a light emitting part for irradiating a laser beam to the wall or ceiling of the power sphere on one side and a light receiving unit for receiving the laser beam reflected from the wall or ceiling of the power sphere on the other side.

The optical scanner 32 may include a beam projector on one side and a light receiver on the other side.

In the laser scanner 30 and the optical scanner 32, the light receiving unit may be configured using a charge coupled device (CCD) camera.

The laser scanner 30 may acquire the external shape of the subject by a rotatable robot using a slit light laser, and the optical scanner 32 employs a spatial coding type three-dimensional scanner using a pattern beam. It is possible.

The laser scanner 30 and the optical scanner 32 may be integrally formed and configured to scan simultaneously. Alternatively, the laser scanner 30 and the optical scanner 32 may be configured to perform scanning while being replaced and installed.

When the laser scanner 30 and the optical scanner 32 are configured as a separate type, the weight and weight of the laser scanner 30 may be easy to transport and handle.

A rotary stage is installed at the upper end of the support 20 on which the laser scanner 30 and the optical scanner 32 are installed to scan in a predetermined angle range (for example, 120 ° to 180 °). Can be configured. The rotary table may be configured to automatically reciprocate rotation at a constant speed using a motor or the like.

The image processing apparatus 40 may be located on the support 20 to receive measurement data and analyze the data in real time.

The support 20 may further include a power supply device 60 for supplying power to the laser scanner 30, the optical scanner 32, the notebook computer 40, and the like.

The power supply device 60 can also be configured to supply alternating current power to direct current power.

The image processing apparatus 40 may be connected to the laser scanner 30 or the optical scanner 32 by a data line to receive and process measurement data from the laser scanner 30 and the optical scanner 32.

The power tool defect detecting apparatus 100 using the 3D laser scanner according to the present invention may further include a digital camera 50 on one side of the support 20 for capturing an image of the power bulb inner surface.

2 is a schematic block diagram of an image processing apparatus of a power sphere defect detecting apparatus using a 3D laser scanner according to an embodiment of the present invention.

Referring to FIG. 2, the image processing apparatus 40 included in the power tool defect detecting apparatus 100 using the 3D laser scanner according to an embodiment of the present invention may include an image collecting unit 41 and an image storing unit 42. ), An image converter 43, a frequency converter 44, a filter 45, a differentiator 46, and an image output unit 47.

The image collecting unit 41 collects an image from the laser scanner 30 or the optical scanner 32.

The image storage unit 42 stores the image collected by the image collecting unit 41. In this case, the database can be sorted and stored sequentially.

The image converter 43 converts the image collected by the collector 41 or the image stored in the image collector 41 into a 2D image when the image is a 3D image. In this case, the conversion may be performed based on depth information included in the 3D image.

The frequency converter 44 converts the two-dimensional image converted by the image converter 43 into data of a frequency domain by performing frequency conversion such as Fourier transform. The reason for the frequency conversion is that the defects such as cracks usually included in the power sphere are deep, and therefore, such an image may appear at a high frequency when the image is converted into data in the frequency domain.

The filtering unit 45 separates high frequency components from image data converted from the frequency converter 44 into data of a frequency domain. Therefore, the filtering unit 45 may be a high frequency filter (HPF).

The differentiator 46 serves to remove linear inclination by generating a second differential image of depth information, for example, a depth value.

The image output unit 47 allows the final two-dimensional image data generated via the respective components to be displayed on the (not shown) display.

By the above configuration, the power sphere defect detection apparatus 100 using the three-dimensional laser scanner according to an embodiment of the present invention is a two-dimensional plane image previously collected in the (not shown) display and stored in the image storage unit 42 And the newly generated two-dimensional plane image are displayed together so that the user can contrast the two plane images with each other to detect defects effectively.

3 is a flow chart of a power sphere defect detection method using a three-dimensional laser scanner according to an embodiment of the present invention.

Referring to FIG. 3, a method for detecting a power sphere defect using a 3D laser scanner according to an embodiment of the present invention may include installing an exploration apparatus 100 (S10), collecting image data (S20), and an image. Processing the data (S30), and detecting the defect (S40).

In the step S10 of installing the exploration apparatus 100, the exploration apparatus 100, which is configured as shown in FIG. 1, is installed to be movable inside the power tool to be explored.

In this case, it is possible to continuously scan the inner surface (wall and ceiling) of the power sphere sequentially while moving the probe 100 at a constant speed or at regular intervals along the track.

In the collecting of the image data (S20), the wall surface and the ceiling of the power tool are scanned by the laser scanner 30 to collect 3D image data.

At this time, it is also possible to additionally collect image data using the optical scanner 32 as needed.

The 3D image data collected as described above is transmitted to and stored in the image processing apparatus 40.

In operation S20, 3D image data obtained by photographing may be output by the digital camera 50 and stored in the image processing apparatus 40.

In the processing of the image data (S30), a two-dimensional plane image is generated by using depth information of the three-dimensional image data collected by the image processing apparatus 40.

In this case, the image processing apparatus 40 may generate a two-dimensional planar image by using depth information of the collected and stored three-dimensional image data and extending the three-dimensional image data into a frequency domain to separate a high frequency region.

In addition, the second derivative (calculation of the difference of the actual coordinates for each pixel) of the depth value is performed to remove linear inclination and generate a planar image.

When the high frequency region is separated in the above, various bendings and nonlinear warpages exist on the wall of the electric power sphere, and the height difference generated when the 2D plane is visualized using the depth information of the 3D data of the nonlinear object. It is possible to solve the problem that it is impossible to generate a readable (readable) image by widening the normalization area, and it is possible to restore the readable digital defect image.

In the process of processing the data in the image processing apparatus 40, extracting and rotating the principal normal vector of the three-dimensional shape data (for example, by analyzing the principal direction component of the three-dimensional image data) By rearranging in a direction perpendicular to the measurement point), distortion of the shape can be minimized.

In the detecting of the defect (S40), a defect such as a crack is detected in comparison with an image previously collected and stored in the two-dimensional plane image obtained by processing the image data (S30).

Based on the two-dimensional plane image, the matching points are searched for two images including the same region, and the feature points that are invariant to the rotation and the change of the size of the image are extracted to reflect the consideration of the rotation and movement during the scanning operation. To increase the matching probability.

In the detecting of the defect (S40), the obtained two-dimensional plane image may be enlarged and displayed on a monitor of the image processing apparatus 40 so that the user may observe the defect and determine whether a defect in the power bulb occurs.

With the above configuration, it is not only possible to scan the monitor of the image processing apparatus 40 in real time and to confirm the presence of a defect, as well as to store the image data of the main surveillance zone to identify the behavior over a long period of time. Therefore, if stable maintenance of an electric power tool is possible, it is possible to ensure safety.

4 is a view showing a two-dimensional planar image image output by the laser scanner 30 in the power sphere defect detection device using a three-dimensional laser scanner according to an embodiment of the present invention, Figure 5 is a portion of the crack occurs Real picture. In addition, Figure 6 is a view showing a two-dimensional planar image output by the optical scanner 32 in the power sphere defect detection device using a three-dimensional laser scanner according to an embodiment of the present invention, Figure 7 is a crack is generated Real picture of the part.

As shown in Fig. 4 to Fig. 7, according to the power tool defect detection apparatus and method using the three-dimensional laser scanner according to the present invention can be more sure the defects of the power tool such as cracks.

The technical spirit of the present invention has been described above with reference to the accompanying drawings, but this is by way of example only and not by way of limitation to the present invention. In addition, it is obvious that any person skilled in the art can make various modifications and imitations without departing from the scope of the technical idea of the present invention.

1 is a view showing a power sphere defect probe using a three-dimensional laser scanner according to an embodiment of the present invention;

2 is a schematic block diagram of an image processing apparatus of a power sphere defect detecting apparatus using a 3D laser scanner according to an embodiment of the present invention;

3 is a flow chart of a power tool defect detection method using a three-dimensional laser scanner according to an embodiment of the present invention;

4 is a view showing a two-dimensional planar image image output by the laser scanner in the power sphere defect detection device using a three-dimensional laser scanner according to an embodiment of the present invention,

5 is an actual photograph of a cracked portion;

6 is a view showing a two-dimensional plane image image output by the optical scanner in the power sphere defect detection device using a three-dimensional laser scanner according to an embodiment of the present invention; And

7 is an actual photograph of a portion where a crack has occurred.

Claims (7)

delete A laser scanner that collects and outputs three-dimensional image data of the wall and ceiling of the power tool; An optical scanner including a beam projector at one side and a light receiver at the other side, and collecting and outputting 3D image data; And And an image processing apparatus for converting 3D image data collected by the laser scanner or the optical scanner into 2D image data using depth information. And the image processing apparatus detects a defect of the power sphere by comparing a previously collected and stored two-dimensional plane image with a newly generated two-dimensional plane image. The image processing apparatus of claim 2, wherein the image processing apparatus comprises: An image collecting unit collecting images from the laser scanner and the optical scanner; An image storage unit storing the image collected by the image collecting unit; An image converting unit converting the image collected by the image collecting unit or the 3D image stored in the image collecting unit into a 2D image; A frequency converter for performing frequency conversion on the two-dimensional image converted by the image converter to convert the data into a frequency domain data; A filtering unit for separating high frequency components from the image data converted from the frequency converter into data of a frequency domain; A differentiator for generating a linear differential image of the depth information to remove linear inclination, and And an image output unit for displaying at least one of the two-dimensional image and the second differential image on a display. The method of claim 3, wherein A base frame having a wheel installed at the bottom thereof and configured to be movable; And Power sphere defect detection device using a three-dimensional laser scanner, characterized in that the base frame further comprises a support that is installed to be adjustable. The apparatus of claim 4, further comprising a digital camera installed at one side of the support for capturing an image of the inner surface of the power bulb. delete A power sphere defect detection method using a three-dimensional laser scanner for detecting a defect inside the power sphere, A scanning device includes a laser scanner or an optical scanner for collecting and outputting image data on a wall and a ceiling of an electric power tool, and an image processing apparatus for converting the collected 3D image data into 2D image data using depth information. Providing; Collecting image data by scanning the wall surface and the ceiling of the power tool using the laser scanner or the optical scanner; Processing the collected image data; And Detecting a defect in the power sphere from the processed image data, The processing of the image data may include: Converting a 3D image into a 2D image among the collected image data; Performing frequency conversion on the converted 2D image to convert the data into frequency domain data; Separating high frequency components from image data converted into data of the frequency domain; Generating a linear differential image of the depth information to remove linear tilt, and And outputting the final image data passed through the above steps to the display.

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