Reinforcement inspection device, reinforcement inspection method, and program

The reinforcement inspection device uses a monocular camera and LiDAR to integrate three-dimensional point cloud data for accurate rebar measurement, addressing the need for multiple image captures in existing systems and simplifying the inspection process.

JP7814237B2Active Publication Date: 2026-02-16MITSUBISHI ELECTRIC ENG CO LTD
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Patent Information

Application Number
JP2022076809
Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
Filing Date
2022-05-09
Publication Date
2026-02-16
Estimated Expiration
2042-05-09

AI Technical Summary

Technical Problem

Existing reinforcement inspection systems require multiple images from different angles using a monocular camera to obtain three-dimensional information about the bar arrangement surface, necessitating complex equipment setups.

Method used

A reinforcement inspection device that utilizes a monocular camera and LiDAR to capture a single image, integrating three-dimensional point cloud data to identify and measure rebar arrangement without requiring multiple photographs, including a three-dimensional information acquisition unit, plane identification, image conversion, and detection units to determine rebar diameter, number, and spacing.

Benefits of technology

Enables efficient reinforcement inspection using a monocular camera and LiDAR to interpolate three-dimensional information, allowing for accurate measurement of rebar diameter, number, and spacing without the need for multiple image captures, simplifying the inspection process and reducing equipment complexity.

✦ Generated by Eureka AI based on patent content.

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Abstract

To provide a reinforcement inspection device, a reinforcement inspection method and a program capable of performing reinforcement inspection without photographing a reinforcement plane a plurality of times.SOLUTION: A reinforcement inspection device 1 includes a three-dimensional information acquisition part 11 that inputs a photographed image obtained by photographing with a monocular camera 2 a reinforcing bar on which an inspection sheet is laid in the longitudinal direction and three-dimensional point cloud data obtained by three-dimensional measurement of reinforcing bar by a lidar, and specifies an inspection sheet range determined by the inspection sheet from the photographed image and acquires three-dimensional point cloud data of the inspection sheet range, a plane specification part 12 that specifies a reinforcement plane to be inspected, an image conversion part 13 that converts the photographed image into a positive-pair image, a detection part 14 that detects a position information of the reinforcing bar, and a reinforcing bar diameter determination part 16 that determines a reinforcing bar diameter of the reinforcing bar based on the pixel value distribution indicated by pixel value scanning lines set for each pixel in the direction intersecting the longitudinal direction of the reinforcing bar indicated by the position information, and a measurement result information generation part 19 that generates and outputs measurement result information indicating the reinforcing bar diameter of the reinforcing bar in the inspection sheet range.SELECTED DRAWING: Figure 1
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Description

[Technical Field]

[0001] The present disclosure relates to a reinforcement inspection device, a reinforcement inspection method, and a program. [Background technology]

[0002] In the construction of reinforced concrete structures, after the rebars have been assembled and arranged, a rebar inspection is carried out to check whether the rebars have been arranged as designed. In a typical rebar inspection, the number of rebars, their diameter, and spacing on the rebar arrangement surface are identified based on images obtained by taking 3D photographs of the rebar arrangement surface to be inspected. However, 3D photography requires large-scale equipment such as a twin-lens or triple-lens camera.

[0003] In contrast, for example, the reinforcement inspection system described in Patent Document 1 judges whether the reinforcement is correct or not by using a superimposed image in which multiple images of markers placed on a specific layer of reinforcement are taken from different angles with a monocular camera and the images are superimposed so that the markers match. Because only a monocular camera is used to photograph the reinforcement, a simpler configuration can be realized than a device that takes three-dimensional photographs. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6801055 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the bar arrangement inspection system described in Patent Document 1 has a problem in that it is necessary to take multiple images from different angles using a monocular camera in order to obtain three-dimensional information about the bar arrangement surface of the inspection target.

[0006] The present disclosure is intended to solve the above-mentioned problems, and aims to provide a reinforcement inspection device, a reinforcement inspection method, and a program that can perform reinforcement inspection without taking multiple photographs of the reinforcement surface. [Means for solving the problem]

[0007] The reinforcement inspection device according to the present disclosure includes: Inspection area with rebars arranged in a grid pattern A photographed image taken by a monocular camera; Inspection Area The three-dimensional point cloud data measured by the lidar is input, and the captured image is laid in the longitudinal direction of the reinforcing bars that cross each other from Identify the inspection sheet range determined by the inspection sheet. hand a three-dimensional information acquisition unit that acquires three-dimensional point cloud data of the inspection sheet range; a plane identification unit that identifies the reinforcement surface of the inspection target based on the three-dimensional point cloud data of the inspection sheet range; an image conversion unit that converts the captured image into a normalized image; and , the inspection sheet was laid in the longitudinal direction Set in the longitudinal direction of the rebar No. 1 Based on the pixel value distribution shown by the pixel value scanning line, No. 1 Detect location information The inspection sheet detects second position information of the reinforcing bars that are arranged crosswise to the reinforcing bars laid in the longitudinal direction. do No. 1 A detection unit; a second detection unit that detects the number and spacing of the reinforcing bars indicated by the second position information based on the pixel value distribution indicated by the second pixel value scanning lines set for each pixel in the longitudinal direction of the inspection sheet; Set for each pixel in the direction intersecting the longitudinal direction of the rebar indicated by the position information No. 1 Based on the pixel value distribution indicated by each pixel value scan line, No. 1 Determine the diameter of the rebar indicated by the location information No. 1 A rebar diameter determination unit; A second rebar diameter determination unit that determines the rebar diameter of the rebar indicated by the second position information based on the pixel value distribution indicated by each second pixel value scanning line set for each pixel in the longitudinal direction of the rebar indicated by the first position information; Inspection sheet range The results obtained in the longitudinal direction of the test sheet and in the direction crossing the longitudinal direction of the test sheet were Rebar diameter , number and spacing of rebars and a measurement result information generating unit that generates and outputs measurement result information indicating the measurement result. [Effects of the Invention]

[0008] According to the present disclosure, Inspection area with rebars arranged in a grid pattern A photographed image taken by a monocular camera; Inspection area The three-dimensional point cloud data measured by the lidar is input, and the captured image is laid in the longitudinal direction of the reinforcing bars that cross each other from Identify the inspection sheet range determined by the inspection sheet. hand3D point cloud data of the inspection sheet range is acquired. Based on the 3D point cloud data of the inspection sheet range, the reinforcement surface of the inspection target is identified. In the reinforcement surface of the inspection target in the orthogonal image converted from the photographed image, , the inspection sheet was laid in the longitudinal direction Set in the longitudinal direction of the rebar No. 1 Based on the pixel value distribution shown by the pixel value scanning line, No. 1 Detect location information The inspection sheet detects second position information of the reinforcing bars that are arranged crosswise to the reinforcing bars laid in the longitudinal direction. do. No. 1 Set for each pixel in the direction intersecting the longitudinal direction of the rebar indicated by the position information No. 1 Based on the pixel value distribution indicated by each pixel value scan line, No. 1 The reinforcing bar diameter of the reinforcing bar indicated by the position information is determined. The reinforcing bar diameter of the reinforcing bar indicated by the second position information is determined based on the pixel value distribution indicated by each second pixel value scanning line set for each pixel in the longitudinal direction of the reinforcing bar indicated by the first position information. Inspection sheet range The results obtained in the longitudinal direction of the test sheet and in the direction crossing the longitudinal direction of the test sheet were Rebar diameter , number and spacing of rebars In this way, the three-dimensional information of the image captured by the monocular camera is interpolated using the three-dimensional point cloud data obtained by three-dimensional measurement using the lidar. As a result, the reinforcement inspection device according to the present disclosure can perform reinforcement inspection without capturing multiple images of the reinforcement surface. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a block diagram showing the configuration of a bar arrangement inspection device according to a first embodiment. [Figure 2] FIG. 10 is a front view showing a check sheet on which markers are printed. [Figure 3] FIG. 10 is a screen diagram showing a reinforcement surface on which an inspection sheet is laid. [Figure 4] 4A, 4B, and 4C are graphs showing the relationship between a function indicating the reinforcement surface in the inspection area and outliers and inliers. [Figure 5] FIG. 10 is an explanatory diagram showing a process of converting a captured image into a normal image. [Figure 6] FIG. 10 is an explanatory diagram showing an outline of a reinforcing bar detection process. [Figure 7] 3 is a flowchart showing a reinforcement bar arrangement inspection method according to the first embodiment. [Figure 8]8A and 8B are block diagrams showing a hardware configuration for realizing the functions of the bar arrangement inspection device according to the first embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] Embodiment 1 FIG. 1 is a block diagram showing the configuration of a reinforcement inspection device 1 according to a first embodiment. The reinforcement inspection device 1 inspects, for example, at least one of the diameter, number, and spacing of adjacent reinforcing bars on a reinforcement surface to be inspected. The reinforcement surface to be inspected is a surface on which reinforcing bars with inspection sheets laid longitudinally are present. The reinforcement surface may also be, for example, a surface on which multiple reinforcing bars are arranged in a lattice pattern, and on which inspection sheets are laid longitudinally on each of a set of reinforcing bars that intersect (for example, perpendicular to) each other among the reinforcing bars arranged in the lattice pattern.

[0011] The reinforcement inspection device 1 is implemented as one function of a smartphone, tablet terminal, or laptop personal computer. As shown in Fig. 1, a monocular camera 2, a lidar 3 (hereinafter referred to as LiDAR 3), and a display unit 4 are connected to the reinforcement inspection device 1 by wire or wirelessly. The reinforcement inspection device 1 is not limited to a device in which the monocular camera 2, LiDAR 3, and display unit 4 are externally attached, and may also be a device in which the monocular camera 2, LiDAR 3, and display unit 4 are mounted.

[0012] For example, a smartphone equipped with a monocular camera 2, a LiDAR 3, and a display unit 4 executes a bar arrangement inspection application for realizing the functions of the bar arrangement inspection device 1 according to embodiment 1, and thereby functions as the bar arrangement inspection device 1. The smartphone uses three-dimensional point cloud data (distance information to the subject) of the bar arrangement surface obtained by three-dimensional measurement by the LiDAR 3 for autofocusing when the monocular camera 2 photographs the bar arrangement surface of the inspection target.

[0013] The positions of the monocular camera 2 and the LiDAR 3 on the smartphone are correlated. For example, when photography is performed by the monocular camera 2 and three-dimensional measurement is performed by the LiDAR 3, the three-dimensional point cloud data obtained by the three-dimensional measurement by the LiDAR 2 is synchronized with the image captured by the monocular camera 2. This makes it possible to associate the pixels of the captured image with the three-dimensional point data. In other words, three-dimensional information can be added to the image captured by the monocular camera 2. This allows the reinforcement inspection device 1 to perform reinforcement inspection using the image captured by the monocular camera 2 in a single shot (one-shot photography).

[0014] The bar arrangement inspection device 1 may be a component included in a server that can communicate with a terminal device equipped with a monocular camera 2, a LiDAR 3, and a display unit 4. For example, the terminal device can perform bar arrangement inspection provided in the form of SaaS (Software as a Service). When performing bar arrangement inspection in the form of SaaS, the terminal device does not need to have a bar arrangement inspection application installed. The bar arrangement inspection application is executed on the server, and the terminal device is provided with measurement result information on a general-purpose web browser. The bar arrangement inspection application is stored in a storage unit provided in the server. Furthermore, an application for reinforcement inspection may be installed in the terminal device. When the application for reinforcement inspection is installed in the terminal device, the application can be executed to perform reinforcement inspection.

[0015] The monocular camera 2 is a camera that is less expensive than a stereo camera, and as mentioned above, may be a camera attached to a smartphone, tablet terminal, or laptop personal computer. Unlike a binocular camera (stereo camera) or trinocular camera, the monocular camera 2 does not require a large-scale device.

[0016] LiDAR3 is a lidar that measures distance by receiving reflected light from a laser pulse irradiated onto a target area at a predetermined measurement period (for example, every 100 milliseconds), and detects 3D point cloud data, which is a collection of 3D points identified by the measured distance. Note that the distance to an object in the target area is measured as the depth of the 3D point.

[0017] The display unit 4 is a display device provided in a smartphone, tablet terminal, or laptop personal computer, and is, for example, a liquid crystal display (LCD) or an organic electroluminescence (EL) display device. The display unit 4 displays the measurement result information of the reinforcing bars.

[0018] The memory unit 5 is a memory unit that stores rebar characteristic information. The rebar characteristic information is a reference spectrum obtained by frequency converting pixel values ​​in a scanning line (hereinafter referred to as a pixel value scanning line) consisting of multiple pixels aligned along the longitudinal direction of the rebar. For example, a fast Fourier transform (hereinafter referred to as an FFT) is used for the frequency conversion.

[0019] When a plurality of reinforcing bars are arranged in a grid pattern in the inspection area and an inspection sheet is laid in the longitudinal direction of the reinforcing bars that intersect with each other, a first reference spectrum is stored in the memory unit 5. The first reference spectrum is a reference spectrum obtained by frequency-converting a first pixel value scanning line set in the longitudinal direction of the reinforcing bar in a photographed image of the reinforcing bar on which the inspection sheet 6 is laid. A second reference spectrum may also be stored in the storage unit 5. The second reference spectrum is a reference spectrum obtained by frequency-converting a second pixel value scanning line set in a direction intersecting the longitudinal direction of the rebar in a photographed image of the rebar on which the inspection sheet 6 is laid.

[0020] As shown in Fig. 1, the reinforcement bar inspection device 1 includes a three-dimensional information acquisition unit 11, a plane identification unit 12, an image conversion unit 13, a first detection unit 14, a second detection unit 15, a first rebar diameter determination unit 16, a second rebar diameter determination unit 17, a correlation calculation unit 18, and a measurement result information generation unit 19. The three-dimensional information acquisition unit 11 receives as input images of rebars laid in the longitudinal direction on an inspection sheet captured by a monocular camera 2, and three-dimensional point cloud data obtained by three-dimensionally measuring the rebars laid in the longitudinal direction on an inspection sheet using a LiDAR 3. The three-dimensional information acquisition unit 11 then identifies the inspection sheet range determined by the inspection sheet from the captured images and acquires three-dimensional point cloud data of the inspection sheet range.

[0021] FIG. 2 is a front view showing an inspection sheet 6 on which markers 7 are printed. As shown in FIG. 2, the inspection sheet 6 is a strip-shaped sheet with markers 7 on its ends. The inspection sheet 6 is laid in the longitudinal direction of the rebars. For example, when inspecting rebars before assembling them into a grid (acceptance inspection), the rebars are aligned with the longitudinal direction of the inspection sheet 6, which is considered to be the reinforcement surface. The markers 7 on the inspection sheet 6 are, for example, identifiers in which an identification shape 7B is drawn on a square base 7A, and AR (augmented reality) markers may also be used.

[0022] The three-dimensional information acquisition unit 11 detects the marker 7 from the captured image captured by the monocular camera 2. For example, when the captured image captured by the monocular camera 2 is input, the three-dimensional information acquisition unit 11 detects the marker 7 from the captured image by using a learning model that outputs detection data of the marker 7. The learning model is machine-learned using captured images including the inspection sheet 6 as learning data, and is, for example, a neural network model. Note that the three-dimensional information acquisition unit 11 may detect the marker 7 by performing pattern matching of the marker 7 in the captured image without using the learning model.

[0023] Next, the three-dimensional information acquisition unit 11 calculates the position information of the detected marker 7. For example, the three-dimensional information acquisition unit 11 binarizes the captured image input from the monocular camera 2, detects the contour of the base 7A of the marker 7, and calculates the position of the marker 7 when it is determined that the base 7A is a square based on the detected contour.

[0024] 2, when the shape formed by the line segment connecting vertices P1 and P2, the line segment connecting vertices P2 and P3, the line segment connecting vertices P3 and P4, and the line segment connecting vertices P4 and P1 is a rectangle (trapezoid), the captured image is an image obtained by monocular camera 2 capturing an image of the reinforcement surface from the front. If any of the four vertices P1 to P4 of the shape of base 7A is not detected or the shape of base 7A is detected distorted, the captured image at that time is an image of the reinforcement surface captured by monocular camera 2 from an oblique direction.

[0025] The three-dimensional information acquisition unit 11 calculates the position information of the marker 7 in the image captured by the monocular camera 2 at a photographing position where the shape of the base 7A is trapezoidal. The three-dimensional information acquisition unit 11 uses the position information of the marker 7 to specify the inspection sheet range where the reinforcement inspection is to be performed. Fig. 3 is a screen image showing a photographed image 2A of a reinforcement surface on which an inspection sheet 6 has been laid, showing a reinforcement surface on which multiple reinforcing bars 8 are arranged in a grid pattern. In Fig. 3, in one of multiple sets of mutually intersecting reinforcing bars 8, an inspection sheet 6 is laid in the longitudinal direction of the reinforcing bars 8, and an inspection sheet 6 is laid in the longitudinal direction of the reinforcing bars 8 that intersect with the longitudinal direction of the reinforcing bars 8.

[0026] For example, the three-dimensional information acquisition unit 11 inputs a captured image 2A of the reinforcement surface shown in FIG. 3 captured by the monocular camera 2 and three-dimensional point cloud data obtained by three-dimensionally measuring the reinforcement surface using the LiDAR 3, identifies an inspection sheet range determined by the inspection sheets 6 laid in the longitudinal direction of the intersecting rebars 8 from the captured image 2A, and acquires three-dimensional point cloud data of the inspection sheet range. The inspection sheet range is a range identified by the positions of markers 7 provided at both ends of the intersecting inspection sheets 6. For example, the inspection sheet range is a rectangular range having one side defined by the rebars 8 laid in the longitudinal direction of the inspection sheet 6 and the rebars 8 intersecting at the positions of the markers 7 provided at the ends of the inspection sheet 6.

[0027] The three-dimensional information acquisition unit 11 identifies the inspection sheet range of the captured image 2A based on the positions of the markers 7, and then acquires three-dimensional point cloud data corresponding to the inspection sheet range from the three-dimensional point cloud data obtained by three-dimensional measurement using the LiDAR 3. The three-dimensional point cloud data corresponding to the inspection sheet range is distance information (depth information) of three-dimensional points on the rebars 8, the inspection sheet 6, and the markers 7 within the inspection sheet range.

[0028] The plane identifying unit 12 identifies the reinforcement surface to be inspected based on the three-dimensional point cloud data of the inspection sheet range. For example, the plane identifying unit 12 detects plane candidates containing multiple three-dimensional points from the three-dimensional point cloud data of the inspection sheet range, and calculates the number of three-dimensional points whose distance from the plane candidate is equal to or less than a threshold for each plane candidate. Then, the plane identifying unit 12 identifies the plane candidate with the largest number of three-dimensional points as the reinforcement surface to be inspected. For example, the reinforcement surface to be inspected is the surface located at the forefront of a multi-story structure in which multiple reinforcing bars are arranged in a lattice pattern.

[0029] For example, the plane identification unit 12 identifies the foreground reinforcement plane using the RANSAC (RANdom Sample Consensus) method. The plane identification unit 12 repeatedly estimates a function indicating plane candidates using three-dimensional point cloud data within the inspection sheet range. Figures 4A, 4B, and 4C are graphs showing the relationship between functions P(1), P(2), and P(3) indicating the planes of each story and outliers 31 and inliers 32, respectively, and show three-dimensional points on the XY coordinate plane. Outliers 31 are three-dimensional points that are not included in the allowable range, and inliers 32 are three-dimensional points that are included in the allowable range.

[0030] In the RANSAC method, the number of 3D points that are inliers 32 is counted for each parameter representing the functions P(1), P(2), and P(3), and the parameter with the highest count is determined to be the optimal parameter. That is, the plane candidate represented by the function to which the determined parameters are applied is determined to be the estimated result of the foreground plane. As is clear from Figures 4A, 4B, and 4C, the parameter representing the function P(3) has the largest number of 3D points that are inliers 32, so the plane identification unit 12 identifies the plane candidate represented by the function P(3) as the reinforcement surface to be inspected.

[0031] The image conversion unit 13 converts the captured image into a normal-oriented image. The normal-oriented image is an image in which the distance between the monocular camera 2 and the reinforcement surface of the inspection target is constant and the reinforcement surface of the inspection target is directly facing the monocular camera 2. All pixels in the normal-oriented image are scaled so that the distance from the monocular camera 2 is constant. As a result, in the normal-oriented image, differences in the size of the rebar depending on the distance between the monocular camera 2 and the reinforcement surface of the inspection target are corrected.

[0032] 5 is an explanatory diagram showing the process of converting the captured image 2A into the oriented image 2B, and shows only the foreground reinforcement surface that appears in each of the captured image 2A and the oriented image 2B. The image conversion unit 13 specifies four points at the four corners of any rectangle among the reinforcing bars 8 arranged in a grid pattern on the reinforcement surface to be inspected in the captured image 2A, and estimates a homography transformation matrix that will give the rectangle a shape as viewed from the front of the monocular camera 2. The image conversion unit 13 converts the captured image 2A into the oriented image 2B based on the homography transformation matrix.

[0033] For example, if the reinforcing bar inspection device 1 is used to perform an acceptance inspection of reinforcing bars and the inspection target is reinforcing bars with the inspection sheet 6 laid in the longitudinal direction before they are assembled in a grid pattern, the reinforcing bar inspection device 1 may not be equipped with the second detection unit 15, the second reinforcing bar diameter determination unit 17, and the correlation calculation unit 18. In this case, the first detection unit 14 functions as a detection unit that detects the position information of the reinforcing bar based on the pixel value distribution indicated by a pixel value scanning line set in the longitudinal direction of the inspection sheet 6 on the reinforcing bar surface of the inspection target in the orthogonal image. Note that the pixel value scanning line is a scanning line composed of pixel values ​​of multiple pixels lined up along the longitudinal direction of the reinforcing bar in the orthogonal image. In the following description, the pixel values ​​are assumed to be luminance values, and the pixel value scanning line is referred to as the luminance value scanning line.

[0034] For example, it is noted that the brightness value distribution differs between the brightness value scanning lines on the inspection sheet 6 laid in the longitudinal direction of the rebar in the orthogonal image and the brightness value scanning lines on the rebar. The detection unit focuses on this and sequentially sets brightness value scanning lines along the longitudinal direction of the rebar in a direction that intersects (e.g., perpendicular to) the longitudinal direction of the rebar. The detection unit then identifies a scanning line where the brightness value distribution indicated by the brightness value scanning lines set sequentially on the inspection sheet 6 has changed significantly, and detects the position information of this scanning line as the position information of the rebar in the orthogonal image.

[0035] FIG. 6 is an explanatory diagram showing an overview of the reinforcing bar detection process, illustrating a case in which inspection sheets 6 are laid in the longitudinal direction of each set of reinforcing bars 8 that intersect with each other among multiple reinforcing bars 8 arranged in a grid pattern on a reinforcing bar arrangement surface. In this case, the reinforcing bar arrangement inspection device 1 shown in FIG. 1 is used to measure the diameter, number, and spacing of the multiple reinforcing bars 8 arranged in a grid pattern. As shown in FIG. 6, the first detection unit 14 detects first position information of the reinforcing bars based on the brightness value distribution indicated by the first brightness value scanning line i set in the longitudinal direction of the reinforcing bars 8 that are laid in the longitudinal direction by the inspection sheet 6, and detects second position information of the reinforcing bars 8 that are arranged so as to intersect with the reinforcing bars 8 that are laid in the longitudinal direction by the inspection sheet 6.

[0036] For example, in the orthogonal image, the brightness value distribution differs between the brightness value scanning line i on the inspection sheet 6 and the brightness value scanning line i on the reinforcing bar 8. Taking note of this, the first detection unit 14 sequentially sets first brightness value scanning lines i along the longitudinal direction of the reinforcing bar 8 in a direction perpendicular to the longitudinal direction of the reinforcing bar 8, as shown in FIG. 6 . The first detection unit 14 then identifies a brightness value scanning line i where the brightness value distribution indicated by the brightness value scanning lines i set sequentially on the inspection sheet 6 changes significantly, and detects the position information of the identified brightness value scanning line i as first position information of the reinforcing bar 8. This allows the first position information indicating the horizontal position of the reinforcing bar 8 in FIG. 6 to be detected.

[0037] In the brightness value distribution indicated by the brightness value scanning line i on the inspection sheet 6 in the orthogonalized image, the brightness value of the rebar 8 (the vertical rebar 8 in FIG. 6) arranged perpendicular to the rebar 8 indicated by the first position information differs from the brightness value on the inspection sheet 6. The first detection unit 14 focuses on this and identifies a position where there is a brightness value change corresponding to the vertical rebar 8 in the brightness value distribution indicated by the brightness value scanning line i on the inspection sheet 6, and detects the identified position as second position information of the rebar 8 in the orthogonalized image. In this way, the second position information indicating the position of the vertical rebar 8 in FIG. 6 is detected.

[0038] The second detection unit 15 detects the number and spacing of the rebars 8 indicated by the second position information based on the brightness value distribution indicated by each second brightness value scanning line j set for each pixel in the longitudinal direction of the rebars 8 (the horizontal direction in FIG. 6 ) indicated by the first position information. For example, in the normal-position image, the brightness value distribution differs between the brightness value scanning line j on the inspection sheet 6 and the brightness value scanning line j on the rebars 8. The second detection unit 15 takes note of this and sets the second brightness value scanning lines j perpendicular to the longitudinal direction of the rebars 8 in order in the longitudinal direction of the rebars 8 as shown in FIG. 6 . Then, the second detection unit 15 determines that the brightness value scanning lines j set in order from the top of the inspection sheet 6, whose brightness value distribution has changed, are the brightness value scanning lines j at the boundary between the inspection sheet 6 and the rebars 8. The second detection unit 15 uses the position information of the boundary brightness value scanning lines j to detect the number of rebars 8 perpendicular to the longitudinal direction of the rebars 8 and the spacing between adjacent rebars 8. As a result, the number of reinforcing bars 8 that are perpendicular to the horizontal reinforcing bars 8 in FIG. 6 and the spacing between the vertical reinforcing bars 8 are detected.

[0039] When the reinforcing bar inspection device 1 performs an acceptance inspection of reinforcing bars and the inspection object is reinforcing bars with an inspection sheet 6 laid in the longitudinal direction before they are assembled in a grid pattern, the first reinforcing bar diameter determination unit 16 functions as a reinforcing bar diameter determination unit that determines the reinforcing bar diameter of the reinforcing bar 8 indicated by the position information detected by the detection unit based on the pixel value distribution indicated by each brightness value scanning line i set for each pixel in a direction intersecting the longitudinal direction of the reinforcing bar 8 indicated by the position information detected by the detection unit.

[0040] For example, the reinforcing bar diameter determination unit sequentially sets brightness value scanning lines i along the longitudinal direction of the reinforcing bar 8 in a direction intersecting (e.g., perpendicular to) the longitudinal direction of the reinforcing bar 8. Of the brightness value scanning lines i set sequentially from the top of the inspection sheet 6, the reinforcing bar diameter determination unit determines a scanning line where the brightness value distribution has changed to be a first scanning line at the boundary where the reinforcing bar changes from the top of the inspection sheet 6 to the top of the reinforcing bar 8, and identifies position information of the first scanning line. Furthermore, the reinforcing bar diameter determination unit advances scanning in a direction intersecting the longitudinal direction of the reinforcing bar 8, and determines a scanning line where the brightness value distribution has changed to be a second scanning line at the boundary where the reinforcing bar changes from the top of the reinforcing bar 8 to the top of the inspection sheet 6, and identifies position information of the second scanning line. The reinforcing bar diameter determination unit can determine the reinforcing bar diameter of the reinforcing bar indicated by the position information detected by the detection unit by converting the difference value between the position information of the first scanning line and the position information of the second scanning line in the normalized image into a distance in real space.

[0041] The first rebar diameter determination unit 16 determines the rebar diameter of the rebar 8 indicated by the first position information based on the brightness value distribution indicated by each first brightness value scanning line i set for each pixel in a direction perpendicular to the longitudinal direction of the rebar 8 indicated by the first position information. For example, as shown in FIG. 6, the first reinforcing bar diameter determination unit 16 sets brightness value scanning lines i along the longitudinal direction of the reinforcing bar 8 in order in a direction perpendicular to the longitudinal direction of the reinforcing bar 8 (the vertical direction in FIG. 6). Next, the first rebar diameter determination unit 16 determines that the scanning line where the brightness value distribution has changed among the brightness value scanning lines i set in order from the top of the inspection sheet 6 is the first scanning line at the boundary where the area changes from the top of the inspection sheet 6 to the top of the rebar 8, and identifies the position information of the first scanning line. Furthermore, the first rebar diameter determination unit 16 scans in a direction perpendicular to the longitudinal direction of the rebar 8, and determines that the scan line where the brightness value distribution has changed is the second scan line at the boundary where the rebar 8 changes to the inspection sheet 6, and identifies the position information of the second scan line. The first rebar diameter determination unit 16 determines the rebar diameter of the rebar 8 indicated by the first position information detected by the first detection unit 14 by converting the difference value between the position information of the first scanning line and the position information of the second scanning line in the facing image into a distance in real space.

[0042] Furthermore, the first reinforcing bar diameter determination unit 16 may determine the reinforcing bar diameter of the reinforcing bar 8 indicated by the first position information based on the correlation value calculated by the correlation calculation unit 18. For example, a spectrum obtained by frequency-converting luminance-value scanning lines set in the longitudinal direction of the rebar on the image is obtained in advance by experiment, and the spectrum is stored as a first reference spectrum in the storage unit 5. The first rebar diameter determination unit 16 frequency-converts each of the luminance-value scanning lines i set in order in a direction perpendicular to the longitudinal direction of the rebar 8 to generate a spectrum indicating changes in luminance values, and outputs the spectrum to the correlation calculation unit 18.

[0043] The correlation calculation unit 18 calculates a correlation value between the frequency conversion spectrum generated by the first rebar diameter determination unit 16 and the first reference spectrum stored in the memory unit 5, and outputs the correlation value to the first rebar diameter determination unit 16. For example, the correlation calculation unit 18 compares the peak positions and peak intensities of the spectra, and calculates the correlation value by quantifying (scoring) the degree of similarity between the two spectra. If the correlation value calculated by the correlation calculation unit 18 is less than a threshold value, the first rebar diameter determination unit 16 determines that the luminance value scanning line i corresponding to the spectrum from which this correlation value was obtained represents the luminance value distribution on the inspection sheet 6 in the orthogonal image.

[0044] On the other hand, if the correlation value calculated by the correlation calculation unit 18 is equal to or greater than the threshold value, the first rebar diameter determination unit 16 determines that the luminance value scanning line i corresponding to the spectrum from which this correlation value was obtained represents the luminance value distribution on the rebar 8 in the facing image. The first rebar diameter determination unit 16 uses the correlation value to detect the position information of the first scanning line and the position information of the second scanning line, and determines the rebar diameter of the rebar 8 indicated by the first position information using the difference value between the position information of the first scanning line and the position information of the second scanning line.

[0045] The second rebar diameter determination unit 17 determines the rebar diameter of the rebar 8 indicated by the second position information based on the brightness value distribution indicated by each second brightness value scanning line j set for each pixel in the longitudinal direction of the rebar 8 indicated by the first position information. 6, the second rebar diameter determination unit 17 sets brightness value scanning lines j that are perpendicular to the longitudinal direction of the rebar 8 indicated by the first position information in order in the longitudinal direction of the rebar 8. Of the brightness value scanning lines j that are set in order from the top of the inspection sheet 6, the second rebar diameter determination unit 17 determines that the scanning line where the brightness value distribution has changed is the first scanning line at the boundary where the top of the inspection sheet 6 changes to the top of the rebar 8, and specifies the position information of the third scanning line.

[0046] Furthermore, the second rebar diameter determination unit 17 scans in the longitudinal direction of the rebar 8, and determines that the scan line where the brightness value distribution changes significantly is the fourth scan line, which is the boundary between above the rebar 8 and above the inspection sheet 6, and identifies the position information of the fourth scan line. The second rebar diameter determination unit 17 determines the rebar diameter of the rebar 8 indicated by the second position information detected by the first detection unit 14 by converting the difference value between the position information of the third scanning line and the position information of the fourth scanning line in the facing image into a distance in real space.

[0047] Furthermore, the second rebar diameter determination unit 17 may determine the rebar diameter of the rebar 8 indicated by the second position information based on the correlation value calculated by the correlation calculation unit 18. For example, the first rebar diameter determination unit 16 stores, as a second reference spectrum, a spectrum obtained by frequency-converting each of the first pixel value scanning lines i set for each pixel in the vertical direction in FIG. 6 by using the first rebar diameter determination unit 16. The correlation calculation unit 18 calculates a correlation value between the spectrum obtained by frequency-converting the second luminance value scanning line j by the second rebar diameter determination unit 17 and the second reference spectrum stored in the storage unit 5.

[0048] 6, the position of the vertical reinforcing bars 8 is specified by the second position information, so in the brightness value distribution indicated by the horizontal brightness value scanning line i, a change in brightness value of the vertical reinforcing bars 8 appears at the position indicated by the second position information. However, the change in brightness value of the vertical reinforcing bars 8 does not appear in the brightness value scanning line i set on the horizontal reinforcing bars 8, but appears strongly in the brightness value scanning line i set on the inspection sheet 6.

[0049] The correlation calculation unit 18 calculates a correlation value between the change in brightness value indicated by the spectrum obtained by frequency-converting the second brightness-place scanning line j set in the vertical direction by the second rebar diameter determination unit 17 and the change in brightness value at the position indicated by the second position information in the spectrum obtained by frequency-converting the horizontal brightness-place scanning line i. The second reinforcing bar diameter determination unit 17 uses the above correlation value to detect the position information of the third scanning line and the position information of the fourth scanning line, and determines the reinforcing bar diameter of the reinforcing bar 8 indicated by the second position information using the difference value between the position information of the third scanning line and the position information of the fourth scanning line.

[0050] Alternatively, a spectrum obtained by frequency-converting a luminance value scanning line j set in a direction perpendicular to the longitudinal direction of the rebar on the image may be obtained in advance by experiment, and the spectrum may be stored as a second reference spectrum in the storage unit 5. In this case, the second rebar diameter determination unit 17 frequency-converts each of the luminance value scanning lines j set in order in the longitudinal direction of the rebar 8 indicated by the first position information, to generate a spectrum indicating changes in luminance values, and outputs the spectrum to the correlation calculation unit 18.

[0051] The correlation calculation unit 18 calculates a correlation value between the frequency conversion spectrum generated by the second rebar diameter determination unit 17 and the second reference spectrum stored in the memory unit 5, and outputs the correlation value to the second rebar diameter determination unit 17. For example, the correlation calculation unit 18 compares the peak positions and peak intensities of the spectra, and calculates the correlation value by quantifying (scoring) the degree of similarity between the two spectra. If the correlation value calculated by the correlation calculation unit 18 is less than a threshold value, the second rebar diameter determination unit 17 determines that the luminance value scanning line j corresponding to the spectrum from which this correlation value was obtained represents the luminance value distribution on the inspection sheet 6 in the normalized image.

[0052] On the other hand, if the correlation value calculated by the correlation calculation unit 18 is equal to or greater than the threshold value, the second rebar diameter determination unit 17 determines that the luminance value scanning line j corresponding to the spectrum from which this correlation value was obtained indicates the luminance value distribution on the rebar 8 in the facing image. The second reinforcing bar diameter determination unit 17 uses the above correlation value to detect the position information of the third scanning line and the position information of the fourth scanning line, and determines the reinforcing bar diameter of the reinforcing bar 8 indicated by the second position information using the difference value between the position information of the third scanning line and the position information of the fourth scanning line.

[0053] The measurement result information generation unit 19 generates and outputs measurement result information that indicates the rebar diameters of the rebars 8 in the inspection sheet range. For example, the measurement result information generation unit 19 generates display control information for displaying the measurement results on an electronic whiteboard as measurement result information and outputs it to the display unit 4. The display unit 4 displays the electronic whiteboard on which the rebar diameters of the measurement results are written, based on the display control information.

[0054] Furthermore, when the reinforcing bar surface is a reinforcing bar surface in which inspection sheets 6 are laid in the longitudinal direction of each set of reinforcing bars 8 that intersect with each other among a plurality of reinforcing bars 8 arranged in a grid pattern as shown in FIG. 3 , the reinforcing bar arrangement inspection device 1 measures the diameter, number, and spacing of the reinforcing bars 8 in the longitudinal direction of the inspection sheet 6 (the horizontal direction in FIG. 3 ) within the inspection sheet range and in a direction intersecting the longitudinal direction of the inspection sheet 6 (the vertical direction in FIG. 3 ). In this way, the diameter, number, and spacing of the reinforcing bars 8 within the inspection sheet range are measured. In this case, the measurement result information generation unit 19 generates display control information for displaying the diameter, number, and spacing of the reinforcing bars 8 within the inspection sheet range on an electronic whiteboard as measurement result information and outputs the generated display control information to the display unit 4. Based on the display control information, the display unit 4 displays an electronic whiteboard on which the diameter, number, and spacing of the reinforcing bars 8 within the inspection sheet range are written.

[0055] Next, a method for inspecting bar arrangement according to the first embodiment will be described. FIG. 7 is a flowchart showing the reinforcement bar arrangement inspection method according to the first embodiment. The three-dimensional information acquisition unit 11 inputs an image taken by a monocular camera 2 of an inspection area where multiple reinforcing bars 8 are arranged in a grid pattern, and three-dimensional point cloud data obtained by three-dimensionally measuring this inspection area using a LiDAR 3, and identifies the inspection sheet range determined by the inspection sheets 6 laid in the longitudinal direction of the reinforcing bars 8 that intersect with each other from the image, and acquires three-dimensional point cloud data of the inspection sheet range (step ST1).

[0056] The plane specifying unit 12 specifies the reinforcement plane of the inspection target in the inspection sheet range based on the three-dimensional point cloud data of the inspection sheet range (step ST2). The image converting unit 13 converts the captured image into a normalized image (step ST3).

[0057] The first detection unit 14 detects first position information of the reinforcing bars 8 based on the brightness value distribution indicated by the first brightness value scanning line i set in the longitudinal direction of the reinforcing bars 8 laid in the longitudinal direction by the inspection sheet 6 on the reinforcing bar surface of the inspection target in the facing image, and detects second position information of the reinforcing bars 8 laid in the longitudinal direction by the inspection sheet 6 (step ST4-1). In addition, the second detection unit 15 detects the number and spacing of the rebars indicated by the second position information based on the brightness value distribution indicated by the second brightness value scanning lines j set for each pixel in the longitudinal direction of the rebars 8 indicated by the first position information (step ST4-2).

[0058] The first rebar diameter determination unit 16 determines the rebar diameter of the rebar 8 indicated by the first position information based on the luminance value distribution indicated by each first luminance value scanning line i set for each pixel in a direction intersecting the longitudinal direction of the rebar 8 indicated by the first position information (step ST5-1). This process is the first rebar diameter determination process. Furthermore, the second rebar diameter determination unit 17 determines the rebar diameter of the rebar 8 indicated by the second position information based on the luminance value distribution indicated by each second luminance value scanning line set for each pixel in the longitudinal direction of the rebar 8 indicated by the first position information (step ST5-2). This process is the second rebar diameter determination process.

[0059] The measurement result information generating unit 19 generates measurement result information indicating the diameter, number, and spacing of the reinforcing bars 8 obtained in the longitudinal direction of the inspection sheet 6 within the inspection sheet range and in a direction intersecting the longitudinal direction of the inspection sheet 6 (step ST6). For example, the measurement result information is display control information for displaying the measurement results, and the display unit 4 displays the measurement results based on the display control information.

[0060] Although the pixel values ​​constituting the pixel value scanning line are brightness values, they are not limited to brightness values ​​as long as there is a difference between the pixel values ​​in the rebar 8 and the pixel values ​​in the inspection sheet 6. For example, color information of the pixels may be used.

[0061] Next, the hardware configuration for realizing the functions of the bar arrangement inspection device 1 will be described. The functions of the three-dimensional information acquisition unit 11, plane identification unit 12, image conversion unit 13, first detection unit 14, second detection unit 15, first rebar diameter determination unit 16, second rebar diameter determination unit 17, correlation calculation unit 18, and measurement result information generation unit 19 provided in the reinforcement bar inspection device 1 are realized by a processing circuit. That is, the reinforcement bar inspection device 1 includes a processing circuit for executing the processes of steps ST1 to ST6 shown in Fig. 7. The processing circuit may be dedicated hardware, or may be a CPU (Central Processing Unit) that executes a program stored in memory.

[0062] Fig. 8A is a block diagram showing a hardware configuration that realizes the functions of the reinforcement bar arrangement inspection device 1. Fig. 8B is a block diagram showing a hardware configuration that executes software that realizes the functions of the reinforcement bar arrangement inspection device 1. In Figs. 8A and 8B, the input interface 100 is an interface that relays the captured images input by the reinforcement bar arrangement inspection device 1 from the monocular camera 2, the three-dimensional point cloud data input by the LiDAR 3, and the rebar characteristic information input by the storage unit 5. The output interface 101 is an interface that relays the measurement result information output from the reinforcement bar arrangement inspection device 1 to the display unit 4.

[0063] 8A, the processing circuit 102 may be, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a combination of these. The functions of the three-dimensional information acquisition unit 11, plane identification unit 12, image conversion unit 13, first detection unit 14, second detection unit 15, first rebar diameter determination unit 16, second rebar diameter determination unit 17, correlation calculation unit 18, and measurement result information generation unit 19 included in the reinforcement bar arrangement inspection device 1 may be realized by separate processing circuits, or these functions may be realized together by a single processing circuit.

[0064] 8B, the functions of the three-dimensional information acquisition unit 11, plane identification unit 12, image conversion unit 13, first detection unit 14, second detection unit 15, first rebar diameter determination unit 16, second rebar diameter determination unit 17, correlation calculation unit 18, and measurement result information generation unit 19 provided in the reinforcement bar arrangement inspection device 1 are realized by software, firmware, or a combination of software and firmware. The software or firmware is written as a program and stored in the memory 104.

[0065] The processor 103 reads and executes the programs stored in the memory 104 to realize the functions of the three-dimensional information acquisition unit 11, plane identification unit 12, image conversion unit 13, first detection unit 14, second detection unit 15, first rebar diameter determination unit 16, second rebar diameter determination unit 17, correlation calculation unit 18 and measurement result information generation unit 19 that are provided in the reinforcement inspection device 1. For example, the bar arrangement inspection device 1 includes a memory 104 for storing a program that, when executed by the processor 103, results in the processing of steps ST1 to ST6 shown in FIG.

[0066] These programs cause the computer to execute the procedures or methods of processing performed by the three-dimensional information acquisition unit 11, plane identification unit 12, image conversion unit 13, first detection unit 14, second detection unit 15, first rebar diameter determination unit 16, second rebar diameter determination unit 17, correlation calculation unit 18, and measurement result information generation unit 19. The memory 104 may be a computer-readable storage medium that stores programs for causing the computer to function as the three-dimensional information acquisition unit 11, plane identification unit 12, image conversion unit 13, first detection unit 14, second detection unit 15, first rebar diameter determination unit 16, second rebar diameter determination unit 17, correlation calculation unit 18, and measurement result information generation unit 19.

[0067] Memory 104 may be, for example, a non-volatile or volatile semiconductor memory such as RAM (Random Access Memory), ROM (Read Only Memory), flash memory, EPROM (Erasable Programmable Read Only Memory), EEPROM (Electrically-EPROM), a magnetic disk, a flexible disk, an optical disk, a compact disk, a mini disk, a DVD, etc.

[0068] The functions of the three-dimensional information acquisition unit 11, plane identification unit 12, image conversion unit 13, first detection unit 14, second detection unit 15, first rebar diameter determination unit 16, second rebar diameter determination unit 17, correlation calculation unit 18, and measurement result information generation unit 19 included in the reinforcement bar arrangement inspection device 1 may be partially implemented by dedicated hardware, and partially implemented by software or firmware. For example, the functions of the three-dimensional information acquisition unit 11 and plane identification unit 12 are implemented by a processing circuit 102, which is dedicated hardware, and the functions of the image conversion unit 13, first detection unit 14, second detection unit 15, first rebar diameter determination unit 16, second rebar diameter determination unit 17, correlation calculation unit 18, and measurement result information generation unit 19 are implemented by a processor 103 reading and executing programs stored in a memory 104. In this way, the processing circuit can implement the above functions by hardware, software, firmware, or a combination of these.

[0069] As described above, the reinforcing bar arrangement inspection device 1 according to the first embodiment includes a three-dimensional information acquisition unit 11 that receives an image of an inspection area photographed by the monocular camera 2 and three-dimensional point cloud data obtained by three-dimensionally measuring the inspection area by the LiDAR 3, identifies an inspection sheet range determined by the inspection sheet 6 laid in the longitudinal direction of the reinforcing bars that intersect with each other from the photographed image, and acquires three-dimensional point cloud data of the inspection sheet range, a plane identification unit 12 that identifies the reinforcing bar arrangement surface of the inspection target, an image conversion unit 13 that converts the photographed image into an orthogonal image, a first detection unit 14 that detects first position information of the reinforcing bar based on the pixel value distribution indicated by the first pixel value scanning line set in the longitudinal direction of the reinforcing bars laid in the longitudinal direction of the inspection sheet 6, and detects second position information of the reinforcing bar that intersects with the reinforcing bar, and a plane identification unit 12 that identifies the reinforcing bar arrangement surface of the inspection target from the photographed image and acquires three-dimensional point cloud data of the inspection sheet range, an image conversion unit 13 that converts the photographed image into an orthogonal image, and a first detection unit 14 that detects second position information of the reinforcing bar that intersects with the reinforcing bar based on the pixel value distribution indicated by the first pixel value scanning line set in the longitudinal direction of the reinforcing bar that intersects with the reinforcing bar, and The inspection device is provided with: a second detection unit 15 that detects the number and spacing of rebars indicated by the second position information based on the pixel value distribution indicated by the second pixel value scanning line set for each pixel in the longitudinal direction of the rebar; a first rebar diameter determination unit 16 that determines the rebar diameter of the rebar indicated by the first position information based on the pixel value distribution indicated by the first pixel value scanning line set for each pixel in the direction intersecting the longitudinal direction of the rebar indicated by the first position information; a second rebar diameter determination unit 17 that determines the rebar diameter of the rebar indicated by the second position information based on the pixel value distribution indicated by the second pixel value scanning line set for each pixel in the longitudinal direction of the rebar indicated by the first position information; and a measurement result information generation unit 19 that generates and outputs the measurement result information that indicates the rebar diameter, number, and spacing obtained in the longitudinal direction of the inspection sheet 6 and the direction intersecting the longitudinal direction of the inspection sheet 6 within the inspection sheet range. Using three-dimensional point cloud data measured in three dimensions by the LiDAR 3, three-dimensional information about the images captured by the monocular camera 2 is interpolated. This allows the reinforcement inspection device 1 to perform reinforcement inspection without taking multiple images of the reinforcement surface.

[0070] In the bar arrangement inspection device 1 according to the first embodiment, measurement result information is output to a terminal device including a monocular camera 2, a LiDAR 3, and a display unit 4, and is displayed on the display unit 4. This allows for bar arrangement inspection using the terminal device.

[0071] In the bar arrangement inspection device 1 according to the first embodiment, the first reinforcing bar diameter determination unit 16 determines the reinforcing bar diameter of the reinforcing bar indicated by the first position information based on a spectrum obtained by frequency-converting a first pixel value scanning line set for each pixel in a direction intersecting the longitudinal direction of the reinforcing bar indicated by the first position information. By using the spectrum obtained by frequency-converting the first pixel value scanning line set for each pixel, the bar arrangement inspection device 1 can accurately determine the reinforcing bar diameter of the reinforcing bar indicated by the first position information.

[0072] In the bar arrangement inspection device 1 according to the first embodiment, the first reinforcing bar diameter determination unit 16 determines the reinforcing bar diameter based on a spectrum obtained by frequency-converting a first pixel value scanning line set for each pixel in a direction intersecting the longitudinal direction of the reinforcing bar indicated by the first position information. The second reinforcing bar diameter determination unit 17 determines the reinforcing bar diameter of the reinforcing bar indicated by the second position information based on a spectrum obtained by frequency-converting a second pixel value scanning line set for each pixel in the longitudinal direction of the reinforcing bar indicated by the first position information. By using the spectrum obtained by frequency-converting the pixel value scanning line set for each pixel, the bar arrangement inspection device 1 can accurately determine the reinforcing bar diameter of the reinforcing bar indicated by the first position information and the reinforcing bar diameter of the reinforcing bar indicated by the second position information.

[0073] In the bar arrangement inspection device 1 according to the first embodiment, the correlation calculation unit 18 calculates a correlation value between a first reference spectrum obtained by frequency-converting the first pixel value scanning line and a spectrum obtained by frequency-converting the first pixel value scanning line set for each pixel in a direction intersecting the longitudinal direction of the rebar indicated by the first position information. The first rebar diameter determination unit 16 determines the rebar diameter of the rebar indicated by the first position information based on the correlation value. By using the correlation value between the first reference spectrum and the spectrum obtained by frequency-converting the first pixel value scanning line, the bar arrangement inspection device 1 can accurately determine the rebar diameter of the rebar indicated by the first position information.

[0074] In the bar arrangement inspection device 1 according to the first embodiment, the correlation calculation unit 18 calculates a correlation value between a second reference spectrum obtained by frequency-converting the second pixel value scanning line and a spectrum obtained by frequency-converting the second pixel value scanning line set for each pixel in the longitudinal direction of the rebar indicated by the first position information. The second rebar diameter determination unit 17 determines the rebar diameter of the rebar indicated by the second position information based on the correlation value. By using the correlation value between the second reference spectrum and the spectrum obtained by frequency-converting the second pixel value scanning line, the bar arrangement inspection device 1 can accurately determine the rebar diameter of the rebar indicated by the second position information.

[0075] In the bar arrangement inspection device 1 according to the first embodiment, the first rebar diameter determination unit 16 stores in the memory unit 5 a spectrum obtained by frequency-converting a first pixel value scanning line set for each pixel in a direction intersecting the longitudinal direction of the rebar indicated by the first position information. The correlation calculation unit 18 calculates a correlation value between the spectrum stored in the memory unit 5 and a spectrum obtained by frequency-converting a second pixel value scanning line set for each pixel in the longitudinal direction of the rebar indicated by the first position information. The second rebar diameter determination unit 17 determines the rebar diameter of the rebar indicated by the second position information based on the correlation value. This allows the bar arrangement inspection device 1 to accurately determine the rebar diameter of the rebar indicated by the second position information.

[0076] In the reinforcement bar arrangement inspection method according to the first embodiment, a three-dimensional information acquisition unit 11 inputs an image of an inspection area where reinforcing bars are arranged in a grid pattern, taken by a monocular camera 2, and three-dimensional point cloud data obtained by three-dimensionally measuring the inspection area by a LiDAR 3, identifies an inspection sheet range determined by an inspection sheet 6 laid in the longitudinal direction of the reinforcing bars that intersect with each other from the image, and acquires three-dimensional point cloud data of the inspection sheet range, a plane identification unit 12 identifies the reinforcement surface of the inspection target in the inspection sheet range based on the three-dimensional point cloud data of the inspection sheet range, an image conversion unit 13 converts the captured image into an orthogonal image, and a first detection unit 14 detects first position information of the reinforcing bars on the reinforcement surface of the inspection target in the orthogonal image based on pixel value distribution indicated by a first pixel value scanning line set by the inspection sheet 6 in the longitudinal direction of the reinforcing bars that are laid in the longitudinal direction, and The second position information is detected, and the second detection unit 15 detects the number and spacing of the reinforcing bars indicated by the second position information based on the pixel value distribution indicated by the second pixel value scanning lines set for each pixel in the longitudinal direction of the reinforcing bars indicated by the first position information, the first reinforcing bar diameter determination unit 16 determines the reinforcing bar diameter of the reinforcing bars indicated by the first position information based on the pixel value distribution indicated by the first pixel value scanning lines set for each pixel in a direction intersecting the longitudinal direction of the reinforcing bars indicated by the first position information, the second reinforcing bar diameter determination unit 17 determines the reinforcing bar diameter of the reinforcing bars indicated by the second position information based on the pixel value distribution indicated by the second pixel value scanning lines set for each pixel in the longitudinal direction of the reinforcing bars indicated by the first position information, and the measurement result information generation unit 19 generates and outputs measurement result information indicating the reinforcing bar diameter, number and spacing of the reinforcing bars obtained in the longitudinal direction of the inspection sheet 6 and the direction intersecting the longitudinal direction of the inspection sheet 6 within the inspection sheet range, respectively. By executing this bar arrangement inspection method with the bar arrangement inspection device 1, it is possible to inspect the bar arrangement without taking multiple images of the bar arrangement surface.

[0077] A computer that executes the program according to the first embodiment functions as the bar arrangement inspection device 1. It is possible to provide the bar arrangement inspection device 1 that can inspect bar arrangement without taking multiple images of the bar arrangement surface.

[0078] Various aspects of the present disclosure are summarized below as appendices. (Appendix 1) a three-dimensional information acquisition unit that inputs a photographed image of a reinforcing bar with an inspection sheet laid in the longitudinal direction, taken by a monocular camera, and three-dimensional point cloud data obtained by three-dimensionally measuring the reinforcing bar with the inspection sheet laid in the longitudinal direction using a lidar, identifies an inspection sheet range determined by the inspection sheet from the photographed image, and acquires the three-dimensional point cloud data of the inspection sheet range; a plane specifying unit that specifies a reinforcement plane to be inspected based on the three-dimensional point cloud data of the inspection sheet range; an image conversion unit that converts the captured image into a normal image; a detection unit that detects position information of the reinforcing bar based on a pixel value distribution indicated by a pixel value scanning line set in the longitudinal direction of the reinforcing bar on the reinforcing bar arrangement surface of the inspection target in the orthogonal image; a reinforcing bar diameter determination unit that determines the reinforcing bar diameter of the reinforcing bar indicated by the position information based on the pixel value distribution indicated by each of the pixel value scanning lines set for each pixel in a direction intersecting the longitudinal direction of the reinforcing bar; a measurement result information generating unit that generates and outputs measurement result information indicating the reinforcing bar diameters of the reinforcing bars in the inspection sheet range. A reinforcement inspection device characterized by the above. (Appendix 2) a three-dimensional information acquisition unit that inputs an image of an inspection area where reinforcing bars are arranged in a grid pattern, taken with a monocular camera, and three-dimensional point cloud data obtained by three-dimensionally measuring the inspection area with a lidar, identifies an inspection sheet range determined by an inspection sheet laid in the longitudinal direction of the reinforcing bars that intersect with each other from the image, and acquires the three-dimensional point cloud data of the inspection sheet range; a plane specifying unit that specifies a reinforcement plane to be inspected based on the three-dimensional point cloud data of the inspection sheet range; an image conversion unit that converts the captured image into a normal image; a first detection unit that detects first position information of the reinforcing bars on the reinforcing bar arrangement surface of the inspection target in the orthogonal image based on a pixel value distribution indicated by a first pixel value scanning line set in the longitudinal direction of the reinforcing bars laid in the longitudinal direction of the inspection sheet, and detects second position information of the reinforcing bars arranged so as to cross the reinforcing bars laid in the longitudinal direction of the inspection sheet; a second detection unit that detects the number and spacing of the reinforcing bars indicated by the second position information based on pixel value distributions indicated by second pixel value scanning lines set for each pixel in the longitudinal direction of the inspection sheet; a first reinforcing bar diameter determination unit that determines the reinforcing bar diameter of the reinforcing bar indicated by the first position information based on the pixel value distribution indicated by each of the first pixel value scanning lines set for each pixel in a direction intersecting the longitudinal direction of the reinforcing bar indicated by the first position information; A second reinforcing bar diameter determination unit that determines the reinforcing bar diameter of the reinforcing bar indicated by the second position information based on the pixel value distribution indicated by the second pixel value scanning line set for each pixel in the longitudinal direction of the reinforcing bar indicated by the first position information; a measurement result information generating unit that generates and outputs measurement result information indicating the rebar diameter, number of rebars, and spacing between rebars obtained in the longitudinal direction of the inspection sheet and in a direction intersecting the longitudinal direction of the inspection sheet within the inspection sheet range. A reinforcement inspection device characterized by the above. (Appendix 3) The measurement result information is output to a terminal device including the monocular camera, the lidar, and a display unit, and is displayed on the display unit. 3. The bar arrangement inspection device according to claim 1 or 2, (Appendix 4) The first reinforcing bar diameter determination unit determines the reinforcing bar diameter of the reinforcing bar indicated by the first position information based on a spectrum obtained by frequency-converting the first pixel value scanning line set for each pixel in a direction intersecting the longitudinal direction of the reinforcing bar indicated by the first position information. 3. The reinforcement bar inspection device according to claim 2, (Appendix 5) The first reinforcing bar diameter determination unit determines the reinforcing bar diameter of the reinforcing bar indicated by the first position information based on a spectrum obtained by frequency-converting the first pixel value scanning line set for each pixel in a direction intersecting the longitudinal direction of the reinforcing bar indicated by the first position information, The second reinforcing bar diameter determination unit determines the reinforcing bar diameter of the reinforcing bar indicated by the second position information based on a spectrum obtained by frequency-converting the second pixel value scanning line set for each pixel in the longitudinal direction of the reinforcing bar indicated by the first position information. 3. The reinforcement bar inspection device according to claim 2, (Appendix 6) a correlation calculation unit that calculates a correlation value between a first reference spectrum obtained by frequency-converting the first pixel value scanning line and a spectrum obtained by frequency-converting the first pixel value scanning line set for each pixel in a direction intersecting the longitudinal direction of the reinforcing bar indicated by the first position information, The first reinforcing bar diameter determination unit determines the reinforcing bar diameter of the reinforcing bar indicated by the first position information based on the correlation value. 6. The bar arrangement inspection device according to claim 4 or 5, (Appendix 7) a correlation calculation unit that calculates a correlation value between a second reference spectrum obtained by frequency-converting the second pixel value scanning line and a spectrum obtained by frequency-converting the second pixel value scanning line set for each pixel in the longitudinal direction of the rebar indicated by the first position information, The second reinforcing bar diameter determination unit determines the reinforcing bar diameter of the reinforcing bar indicated by the second position information based on the correlation value. 6. The reinforcement bar inspection device according to claim 5, (Appendix 8) The first reinforcing bar diameter determination unit stores in a storage unit a spectrum obtained by frequency-converting the first pixel value scanning line set for each pixel in a direction intersecting the longitudinal direction of the reinforcing bar indicated by the first position information, a correlation calculation unit that calculates a correlation value between the spectrum stored in the storage unit and a spectrum obtained by frequency-converting the second pixel value scanning line set for each pixel in the longitudinal direction of the reinforcing bar indicated by the first position information, The second reinforcing bar diameter determination unit determines the reinforcing bar diameter of the reinforcing bar indicated by the second position information based on the correlation value. 6. The reinforcement bar inspection device according to claim 5, (Appendix 9) A reinforcement inspection method using a reinforcement inspection device, a three-dimensional information acquisition unit inputs a photographed image of an inspection area where reinforcing bars are arranged in a grid pattern, taken by a monocular camera, and three-dimensional point cloud data obtained by three-dimensionally measuring the inspection area by a lidar, identifies an inspection sheet range determined by inspection sheets laid in the longitudinal direction of the reinforcing bars that intersect with each other from the photographed image, and acquires the three-dimensional point cloud data of the inspection sheet range; a step in which a plane specifying unit specifies a reinforcement surface to be inspected in the inspection sheet range based on the three-dimensional point cloud data of the inspection sheet range; an image conversion unit converting the captured image into a normal image; a step in which a first detection unit detects first position information of a reinforcing bar on the reinforcing bar arrangement surface of the inspection target in the orthogonal image based on a pixel value distribution indicated by a first pixel value scanning line set in the longitudinal direction of the reinforcing bar by the inspection sheet, and detects second position information of a reinforcing bar arranged so as to cross the reinforcing bar laid in the longitudinal direction by the inspection sheet; A step in which a second detection unit detects the number and spacing of the reinforcing bars indicated by the second position information based on pixel value distributions indicated by second pixel value scanning lines set for each pixel in the longitudinal direction of the reinforcing bars indicated by the first position information; A step in which a first reinforcing bar diameter determination unit determines the reinforcing bar diameter of the reinforcing bar indicated by the first position information based on the pixel value distribution indicated by each of the first pixel value scanning lines set for each pixel in a direction intersecting the longitudinal direction of the reinforcing bar indicated by the first position information; A step in which a second reinforcing bar diameter determination unit determines the reinforcing bar diameter of the reinforcing bar indicated by the second position information based on the pixel value distribution indicated by each of the second pixel value scanning lines set for each pixel in the longitudinal direction of the reinforcing bar indicated by the first position information; a step in which the measurement result information generating unit generates and outputs measurement result information indicating the diameter, number, and spacing of reinforcing bars obtained in the longitudinal direction of the inspection sheet and in a direction intersecting the longitudinal direction of the inspection sheet within the inspection sheet range. A reinforcement inspection method characterized by the above. (Appendix 10) A program for causing a computer to function as the reinforcement inspection device according to any one of appendices 1 to 8.

[0079] Any of the components of the embodiments may be modified or omitted. [Explanation of symbols]

[0080] 1 Reinforcement inspection device, 2 Monocular camera, 2A Captured image, 2B Oriented image, 3 LiDAR, 4 Display unit, 5 Memory unit, 6 Inspection sheet, 7 Marker, 7A Substrate, 7B Identification shape, 8 Reinforcement bar, 11 Three-dimensional information acquisition unit, 12 Plane identification unit, 13 Image conversion unit, 14 First detection unit, 15 Second detection unit, 16 First reinforcement bar diameter determination unit, 17 Second reinforcement bar diameter determination unit, 18 Correlation calculation unit, 19 Measurement result information generation unit, 31 Outlier, 32 Inlier, 100 Input interface, 101 Output interface, 102 Processing circuit, 103 Processor, 104 Memory.

Claims

1. a three-dimensional information acquisition unit that inputs an image of an inspection area where reinforcing bars are arranged in a grid pattern, taken with a monocular camera, and three-dimensional point cloud data obtained by three-dimensionally measuring the inspection area with a lidar, identifies an inspection sheet range determined by an inspection sheet laid in the longitudinal direction of the reinforcing bars that intersect with each other from the image, and acquires the three-dimensional point cloud data of the inspection sheet range; a plane specifying unit that specifies a reinforcement plane to be inspected based on the three-dimensional point cloud data of the inspection sheet range; an image conversion unit that converts the captured image into a normal image; a first detection unit that detects first position information of the reinforcing bars on the reinforcing bar arrangement surface of the inspection target in the orthogonal image based on a pixel value distribution indicated by a first pixel value scanning line set in the longitudinal direction of the reinforcing bars laid in the longitudinal direction of the inspection sheet, and detects second position information of the reinforcing bars arranged so that the inspection sheet crosses the reinforcing bars laid in the longitudinal direction; a second detection unit that detects the number and spacing of the reinforcing bars indicated by the second position information based on pixel value distributions indicated by second pixel value scanning lines set for each pixel in the longitudinal direction of the inspection sheet; a first reinforcing bar diameter determination unit that determines the reinforcing bar diameter of the reinforcing bar indicated by the first position information based on the pixel value distribution indicated by each of the first pixel value scanning lines set for each pixel in a direction intersecting the longitudinal direction of the reinforcing bar indicated by the first position information; a second reinforcing bar diameter determination unit that determines the reinforcing bar diameter of the reinforcing bar indicated by the second position information based on the pixel value distribution indicated by the second pixel value scanning line set for each pixel in the longitudinal direction of the reinforcing bar indicated by the first position information; a measurement result information generating unit that generates and outputs measurement result information indicating the rebar diameter, number of rebars, and spacing between rebars obtained in the longitudinal direction of the inspection sheet and in a direction intersecting the longitudinal direction of the inspection sheet within the inspection sheet range. A reinforcement inspection device characterized by the above.

2. The measurement result information is output to a terminal device including the monocular camera, the lidar, and a display unit, and is displayed on the display unit.

2. The reinforcing bar inspection device according to claim 1.

3. The first reinforcing bar diameter determination unit determines the reinforcing bar diameter of the reinforcing bar indicated by the first position information based on a spectrum obtained by frequency-converting the first pixel value scanning line set for each pixel in a direction intersecting the longitudinal direction of the reinforcing bar indicated by the first position information.

2. The reinforcing bar inspection device according to claim 1.

4. The first reinforcing bar diameter determination unit determines the reinforcing bar diameter of the reinforcing bar indicated by the first position information based on a spectrum obtained by frequency-converting the first pixel value scanning line set for each pixel in a direction intersecting the longitudinal direction of the reinforcing bar indicated by the first position information, The second reinforcing bar diameter determination unit determines the reinforcing bar diameter of the reinforcing bar indicated by the second position information based on a spectrum obtained by frequency-converting the second pixel value scanning line set for each pixel in the longitudinal direction of the reinforcing bar indicated by the first position information.

2. The reinforcing bar inspection device according to claim 1.

5. a correlation calculation unit that calculates a correlation value between a first reference spectrum obtained by frequency-converting the first pixel value scanning line and a spectrum obtained by frequency-converting the first pixel value scanning line set for each pixel in a direction intersecting the longitudinal direction of the reinforcing bar indicated by the first position information, The first reinforcing bar diameter determination unit determines the reinforcing bar diameter of the reinforcing bar indicated by the first position information based on the correlation value.

5. The reinforcing bar inspection device according to claim 4.

6. a correlation calculation unit that calculates a correlation value between a second reference spectrum obtained by frequency-converting the second pixel value scanning line and a spectrum obtained by frequency-converting the second pixel value scanning line set for each pixel in the longitudinal direction of the reinforcing bar indicated by the first position information; The second reinforcing bar diameter determination unit determines the reinforcing bar diameter of the reinforcing bar indicated by the second position information based on the correlation value. The bar arrangement inspection device according to claim 5 .

7. The first reinforcing bar diameter determination unit stores in a storage unit a spectrum obtained by frequency-converting the first pixel value scanning line set for each pixel in a direction intersecting the longitudinal direction of the reinforcing bar indicated by the first position information, a correlation calculation unit that calculates a correlation value between the spectrum stored in the storage unit and a spectrum obtained by frequency-converting the second pixel value scanning line set for each pixel in the longitudinal direction of the reinforcing bar indicated by the first position information, The second reinforcing bar diameter determination unit determines the reinforcing bar diameter of the reinforcing bar indicated by the second position information based on the correlation value.

5. The reinforcing bar inspection device according to claim 4.

8. A reinforcement inspection method using a reinforcement inspection device, a three-dimensional information acquisition unit inputs a photographed image of an inspection area where reinforcing bars are arranged in a grid pattern, taken by a monocular camera, and three-dimensional point cloud data obtained by three-dimensionally measuring the inspection area by a lidar, identifies an inspection sheet range determined by inspection sheets laid in the longitudinal direction of the reinforcing bars that intersect with each other from the photographed image, and acquires the three-dimensional point cloud data of the inspection sheet range; a step in which a plane specifying unit specifies a reinforcement surface to be inspected in the inspection sheet range based on the three-dimensional point cloud data of the inspection sheet range; an image conversion unit converting the captured image into a normal image; a step in which a first detection unit detects first position information of a reinforcing bar on the reinforcing bar arrangement surface of the inspection target in the orthogonal image based on a pixel value distribution indicated by a first pixel value scanning line set in the longitudinal direction of the reinforcing bar by the inspection sheet, and detects second position information of a reinforcing bar arranged so as to cross the reinforcing bar laid in the longitudinal direction by the inspection sheet; a step in which a second detection unit detects the number and spacing of the reinforcing bars indicated by the second position information based on pixel value distributions indicated by second pixel value scanning lines set for each pixel in the longitudinal direction of the reinforcing bars indicated by the first position information; A step in which a first reinforcing bar diameter determination unit determines the reinforcing bar diameter of the reinforcing bar indicated by the first position information based on the pixel value distribution indicated by each of the first pixel value scanning lines set for each pixel in a direction intersecting the longitudinal direction of the reinforcing bar indicated by the first position information; A step in which a second reinforcing bar diameter determination unit determines the reinforcing bar diameter of the reinforcing bar indicated by the second position information based on the pixel value distribution indicated by each of the second pixel value scanning lines set for each pixel in the longitudinal direction of the reinforcing bar indicated by the first position information; a step in which the measurement result information generating unit generates and outputs measurement result information indicating the diameter, number, and spacing of reinforcing bars obtained in the longitudinal direction of the inspection sheet and in a direction intersecting the longitudinal direction of the inspection sheet within the inspection sheet range. A reinforcement inspection method characterized by the above.

9. A program for causing a computer to function as the bar arrangement inspection device according to any one of claims 1 to 7.

Citation Information

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