Peeling / falling identification device, method, and program

Abstract

Provided are a peeling / falling identification device, method, and program capable of identifying a peeled-off / fallen-off portion of the surface of concrete, etc., of a building. A processor of the peeling / falling identification device acquires three-dimensional measurement data of the surface of the building as measured by a three-dimensional measurement device such as LiDAR (step S10). The processor compares the three-dimensional measurement data and reference surface data of the building so as to detect a recessed portion in the surface of the building (step S20). The processor determines whether the detected recessed portion is recessed beyond a first threshold value and whether the recessed portion is a crack (steps S30, S40), and identifies the recessed portion as being a peeled-off / fallen-off portion when it is determined that the recessed portion is recessed beyond the first threshold value and is not a crack (step S50).

Description

Peeling and peeling identification device, method, and program

[0001] The present invention relates to a peeling and flaking identification device, method, and program, and more particularly to a technique for identifying peeling and flaking portions on the surface of concrete or the like of a building.

[0002] Traditionally, inspections of structures such as tunnels and bridges have typically been carried out by inspectors patrolling the site, and during these inspections, inspectors may find areas of peeling or debris (concrete pieces) on the surface of the structure.

[0003] However, because patrols are man-dependent and cannot always be seen during daylight hours, peeling may be overlooked. To avoid overlooking the problem, the number of patrols is increased and multiple people are required to monitor, but this requires time and money and is not very accurate.

[0004] In recent years, new technologies described in Patent Documents 1-3 and the like have been developed and introduced into infrastructure inspection, and digital transformation (DX) of human-dependent inspections is expected.

[0005] The spalling prediction and diagnosis method described in Patent Document 1 takes an infrared thermal image of the surface of a concrete structure using an infrared camera, and simultaneously measures the outside air temperature near the surface.Based on the infrared thermal image and the outside air temperature, it calculates the temperature difference at the spalling section, which is the temperature difference between the healthy part and the spalled part, and the measured temperature environment, which is the difference between the surface temperature of the healthy part and the outside air temperature.It calculates a temperature environment coefficient as the ratio of the calculated temperature difference at the spalled part to the calculated measured temperature environment, and quantitatively evaluates the risk of the cover concrete (concrete from the steel bar surface to the concrete surface) spalling based on the temperature environment coefficient.

[0006] The inspection method described in Patent Document 2 involves striking an object to be inspected with an inspection hammer device, and determining the state of the object to be inspected based on time history data of sound pressure generated by the striking.

[0007] The non-destructive inspection method for concrete structures described in Patent Document 3 involves contacting an ultrasonic transmitter and receiver with the submerged portion of a concrete structure that is partially or completely submerged, irradiating shear ultrasonic waves from the transmitter into the concrete structure while detecting resonant vibrations of the concrete structure with the receiver, and determining backside damage and / or internal damage to the concrete structure based on the waveform detected by the receiver.

[0008] JP 2016-006398 A JP 2020-098098 A JP 2006-105680 A

[0009] However, none of the techniques described in Patent Documents 1 to 3 identify peeling and flaking areas on the surface of concrete, etc. of a building. In particular, the technique described in Patent Document 1 is a method for quantitatively evaluating the risk of cover concrete peeling, and is not a technique for actually identifying areas where cover concrete has peeled and flaked.

[0010] One embodiment of the technique of the present disclosure provides a peeling and flaking identification device, method, and program that can identify peeling and flaking portions on the surface of concrete or the like of a building.

[0011] The invention of the first aspect is a peeling and flaking identification device that includes a processor and a memory that stores a program to be executed by the processor, in which the processor acquires three-dimensional measurement data of the surface of a building measured by a measuring device, compares the three-dimensional measurement data with reference surface data of the building to detect a depression in the surface of the building, and if the depression is determined to be a depression that exceeds a first threshold and is not a crack, identifies the depression as a peeling and flaking portion on the surface of the building.

[0012] According to a first aspect of the present invention, depressions on the surface of a building are detected by comparing three-dimensional measurement data of the surface of the building with reference surface data of the building. To distinguish the detected depressions from depressions caused during construction, depressions that exceed a first threshold are identified. Furthermore, it is determined whether the depressions that exceed the first threshold are depressions caused by peeling or delamination or depressions caused by cracks, and the peeling or delamination is finally identified.

[0013] In the second aspect of the peeling and falling identification device of the present invention, in the first aspect, it is preferable that the processor measures the width and height of the depression portion and determines that the depression portion is not a crack if the shorter of the width or height exceeds a second threshold value.

[0014] In the third aspect of the peeling and falling identification device of the present invention, in the first aspect, it is preferable that the processor measures the area of ​​the depression portion and, if the area exceeds a third threshold, determines that the depression portion is not a crack.

[0015] In the peeling and delamination identifying device according to the fourth aspect of the present invention, in the first aspect, the processor preferably acquires an image of the building captured by the imaging device, detects cracks in the building based on the captured image, and determines whether or not a depression is a crack based on the crack detection result, because detecting cracks based on the captured image is preferable to detecting cracks from three-dimensional measurement data.

[0016] In the peeling and falling identification device of the fifth aspect of the present invention, in any of the first to fourth aspects, it is preferable that the reference surface data is surface data obtained by averaging the unevenness of the surface of the building indicated by the three-dimensional measurement data, or surface data on the design of the building.

[0017] A sixth aspect of the present invention relates to a peeling and delamination identifying device, and is preferably the same as any of the first to fifth aspects, wherein the memory stores three-dimensional measurement data of the structure surface measured by the measuring device for each inspection of the structure, and the processor acquires a plurality of pieces of three-dimensional measurement data of the structure surface measured for each inspection, acquires difference data for the same measurement point on the structure surface based on the plurality of pieces of three-dimensional measurement data, and detects at least the depressions among the raised and depressed portions of the structure surface based on the difference data. In this case, among the different three-dimensional measurement data used during inspection to acquire the difference data, the earlier three-dimensional measurement data during inspection serves as reference surface data for the later three-dimensional measurement data during inspection.

[0018] In a seventh aspect of the present invention, the peeling and delamination identification device is preferably configured such that, when a raised portion and a depressed portion are detected in the same portion of the surface of a structure in chronological order of inspection, the depressed portion is identified as a peeling and delamination portion on the surface of the structure. The raised portion is a candidate portion for a peeling and delamination portion, and when the raised portion changes into a depressed portion, the depressed portion can be identified as a peeling and delamination portion.

[0019] In the peeling and delaminating identification device of the eighth aspect of the present invention, in the sixth aspect, it is preferable that the processor identifies a depression as a peeling and delaminating part on the surface of a building when the change in the difference data turns negative, when the change in the difference data turns from positive to negative, or when the change in the difference data decreases beyond a threshold value.

[0020] In a ninth aspect of the present invention, in any one of the first to eighth aspects, the processor preferably displays the identified peeled and delaminated portions in an identifiable manner on a screen of a display that displays three-dimensional measurement data, design surface data of the building, or an image of the building captured by an imaging device, allowing a user (inspector) to check on the screen of the display where the peeled and delaminated portions exist on the building.

[0021] A tenth aspect of the present invention provides a peeling and falling apart identifying device according to any one of the first to ninth aspects, wherein the measurement device includes a LiDAR or a stereo camera.

[0022] In an eleventh aspect of the present invention, in the tenth aspect of the peeling and delamination identifying device, it is preferable that the LiDAR measures three-dimensional measurement data using a frequency modulated continuous wave (FMCW) method, which makes it possible to detect surface characteristics of a building that cannot be confirmed visually.

[0023] A twelfth aspect of the present invention provides a peeling and falling debris identifying device according to any one of the first to eleventh aspects, wherein the material of the surface of the building preferably includes concrete or a concrete repair material.

[0024] The invention of the thirteenth aspect is a peeling and flaking identification method in which a processor identifies peeling and flaking on the surface of a building, the method acquiring three-dimensional measurement data of the surface of the building measured by a measuring device, comparing the three-dimensional measurement data with reference surface data of the building to detect depressions on the surface of the building, and if the depression is determined to be a depression that exceeds a first threshold and is not a crack, identifying the depression as a peeling and flaking part on the surface of the building.

[0025] In the peeling and falling identification method according to the 14th aspect of the present invention, in the 13th aspect, it is preferable that the processor measures the width and height of the depression portion and determines that the depression portion is not a crack if the shorter of the width or height exceeds a second threshold value.

[0026] In the method for identifying peeling and falling off according to the 15th aspect of the present invention, in the 13th aspect, it is preferable that the processor measures the area of ​​the depression portion and, if the area exceeds a third threshold, determines that the depression portion is not a crack.

[0027] In the method for identifying peeling and falling debris according to the 16th aspect of the present invention, in the 13th aspect, it is preferable that the processor acquires an image of the building captured by an imaging device, detects cracks in the building based on the captured image, and determines whether the depression is a crack or not based on the crack detection results.

[0028] The invention of the seventeenth aspect is a peeling and flaking identification program that identifies peeling and flaking on the surface of a building, and causes a computer to execute the following functions: a function to acquire three-dimensional measurement data of the surface of the building measured by a measuring device; a function to compare the three-dimensional measurement data with reference surface data of the building to detect depressions on the surface of the building; and a function to identify the depression as a peeling and flaking part on the surface of the building if the depression is determined to be a depression that exceeds a first threshold and is not a crack.

[0029] According to the present invention, peeled and fallen portions on the surface of concrete or the like of a building can be identified with high accuracy.

[0030] FIG. 1 is a graph showing the relationship between the elapsed time after construction of a building and the surface displacement and peeling / fracture of the building, and a diagram showing an example of a cross-section of a building at each inspection. FIG. 2 is a schematic diagram of a building inspection system including a peeling / fracture identifying device according to the present invention. FIG. 3 is an external view of an embodiment of a three-dimensional measuring device including an FMCW-type LiDAR. FIG. 4 is a diagram showing an embodiment of measuring the three-dimensional shape of a building's surface using a stereo camera. FIG. 5 is a cross-sectional view of the vicinity of a building's surface showing an example of a mechanism by which the building's surface peels. FIG. 6 is a cross-sectional view of the vicinity of a building's surface showing another example of a mechanism by which the building's surface peels. FIG. 7 is a block diagram showing an embodiment of the hardware configuration of a peeling / fracture identifying device according to the present invention. FIG. 8 is a diagram showing a method for identifying peeled / fracture portions on the surface of a building. FIG. 9 is a captured image of a building including peeled / fracture portions and cracked portions. FIG. 10 is a diagram showing an example of the surface texture of a building based on a large number of measurement points (measurement points distributed two-dimensionally) measured by a three-dimensional measuring device. FIG. 11 is a diagram showing another example of the surface texture of a building based on a large number of measurement points measured by a three-dimensional measuring device. Fig. 12 is a diagram showing another method for detecting depressions on the surface of a building. Fig. 13 is a diagram showing an example of a screen of a display device displaying peeled and fallen parts, etc. Fig. 14 is a flowchart showing an embodiment of a peeled and fallen part identification method according to the present invention.

[0031] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a peeling and peeling identifying device, method, and program according to the present invention will now be described with reference to the accompanying drawings.

[0032] [Outline of the Invention] FIG. 1 is a graph showing the relationship between the time elapsed after construction of a building and the surface displacement and peeling / falling of the building, and a diagram showing an example of a cross section of the building at each inspection time.

[0033] In Figure 1, the displacement of the structure's surface is measured at the start of inspection of the structure (the start of measurement during construction) t1, and at each subsequent inspection point (t2, t3, t4, t5, ...). By comparing the displacements at the same position on the structure's surface, it is possible to observe areas where the surface rises over time since the construction of the structure.

[0034] In the example shown in Figure 1, the building is in a normal state (A) at the start of measurement time t1, but at the inspection time t2, the surface has slightly bulged due to deterioration of the building (cracks (B)). At this stage, the bulge is not noticeable by visual inspection. Note that "cracks" are often caused by corrosion and thickening of the steel (reinforcing bars) inside the building.

[0035] At the initial stage of lifting (C) shown at inspection time t3, as corrosion of the reinforcing bars progresses, cracks also progress, causing the surface of the building to swell (lifting occurs).

[0036] At the final stage of the lifting (D) shown at inspection time t4, the "cracks" have progressed further, reaching the surface of the building, and the "lifting" has become even larger.

[0037] The inspection time point t5 indicates the time point when the concrete cover (concrete from the rebar surface to the concrete surface) falls ((E) Peeling / Falling).

[0038] In the example shown in Figure 1, the displacement (amount of rise) of the surface of the building measured at each inspection gradually increases, and it can be seen that the cover concrete eventually peels off and falls off.

[0039] Regardless of the cause, spalling causes abnormalities on the concrete surface, and highly accurate surface displacement measurement makes it possible to detect even the slightest spalling without missing it.

[0040] Therefore, the present invention acquires three-dimensional measurement data that indicates the surface displacement of a structure, and detects depressions on the surface of the structure based on the three-dimensional measurement data. These depressions can be detected by comparing the three-dimensional measurement data with a reference surface (reference surface data).

[0041] Furthermore, in order to distinguish between unevenness (depressions) on the surface of the building during construction and depressions that are peeling and falling off, depressions exceeding a first threshold are detected, thereby eliminating depressions caused by slight unevenness on the surface of the building during construction.

[0042] If it is determined that a depression exceeding the first threshold is not a depression caused by a crack, the depression is identified as a peeled or separated portion.

[0043] [Schematic Configuration of Inspection System] FIG. 2 is a schematic diagram of a building inspection system including a peeling and falling off identifying device according to the present invention.

[0044] The inspection system shown in FIG. 2 is a system for inspecting railway tunnels, and includes a three-dimensional measuring device 10, a data processing device 14, and a power supply device 16.

[0045] The three-dimensional measuring device 10 is mounted on a tripod 12, but may also be mounted on a carriage 18 that travels on a railroad track.

[0046] In this example, the three-dimensional measuring device 10 is a LiDAR (Light Detection And Ranging), and in particular, a FMCW (Frequency Modulated Continuous Wave) LiDAR that can measure distances on the order of several hundred μm, but the present invention is not limited to using distance data (three-dimensional measurement data) measured by an FMCW LiDAR.

[0047] [Three-dimensional Measuring Apparatus] FIG. 3 is an external view of one embodiment of a three-dimensional measuring apparatus including an FMCW LiDAR.

[0048] In FIG. 3, the three-dimensional measuring device 10 is mounted on a carriage 18 that travels on the railroad tracks as shown in FIG. 2, and measures the distance to the surface of a tunnel, which is a railway structure.

[0049] In addition to the three-dimensional measuring device 10, the carriage 18 is also equipped with a data processing device 14 and a power supply device 16. The power supply device 16 supplies power to the three-dimensional measuring device 10 and the data processing device 14.

[0050] The three-dimensional measuring device 10 measures the distance to a tunnel wall (surface) 20 to obtain three-dimensional measurement data indicating the shape of the tunnel wall 20 .

[0051] In the example shown in Fig. 3, the three-dimensional measuring device 10 scans the wall surface 20 shown in Fig. 3 in the left-right direction (main scanning direction) with an FMCW laser beam at high speed, while also moving the scanning line up and down (sub-scanning direction) across the wall surface 20. This measures the distance from the measurement head of the three-dimensional measuring device 10 to multiple measurement points on each scanning line of the laser beam. Then, three-dimensional data in a polar coordinate system consisting of the irradiation direction of the laser beam and the measured distance is converted into three-dimensional data in a Cartesian coordinate system, thereby obtaining three-dimensional measurement data that indicates the shape of the wall surface 20. In this example, three-dimensional measurement data (point cloud data) of multiple measurement points is obtained as the three-dimensional measurement data.

[0052] The three-dimensional measuring device 10 is considered to measure the uneven shape of the minute wall surface 20 under the following conditions: Measurement accuracy: 50 μm Measurement distance: 2 to 7 m Measurement speed: 10 m for area 2 / sec (laser light speed is equivalent to 4000 rpm)

[0053] Furthermore, the three-dimensional measuring device 10 acquires three-dimensional data of the wall surface 20 at regular intervals while the carriage 18 is moving, and it is preferable to acquire the three-dimensional data so that the measurement areas of the three-dimensional data acquired at each interval partially overlap, in order to synthesize the three-dimensional data acquired at each interval into a panoramic image.

[0054] The three-dimensional measuring device 10 can achieve the above measurement accuracy by using an FMCW LiDAR, but the conditions such as the measurement accuracy of the three-dimensional measurement data required in the present invention are not limited to the above example, and various three-dimensional measuring devices can be applied, not just FMCW LiDAR.

[0055] For example, instead of the FMCW LiDAR, a TOF (Time of Flight) LiDAR can be used, which measures the time of flight of pulsed projected light to measure the distance to the wall surface 20. Also, the three-dimensional shape of the wall surface 20 can be measured using a stereo camera.

[0056] FIG. 4 is a diagram showing an embodiment in which the three-dimensional shape of the surface of a building is measured using a stereo camera.

[0057] The stereo camera shown in FIG. 4 is composed of a left camera 30L and a right camera 30R, and measures the distance to the wall surface 20 of the photographing target by triangulation.

[0058] Other three-dimensional measuring devices that can be used to measure the distance to the wall surface 20 (i.e., three-dimensional measurement data of the wall surface) include the laser radar three-dimensional shape measuring device described in Japanese Patent Laid-Open No. 9-297014, the imaging device described in Japanese Patent Laid-Open No. 2021-2016-31249, a measuring device using a light-cutting method using a slit laser light projector, an FM laser radar type distance measuring device described in Japanese Patent No. 3194586, and an optical rangefinder described in Japanese Patent No. 3583906.

[0059] The three-dimensional shape of the tunnel wall surface 20 is measured by the three-dimensional measuring device 10 at the start of measurement (construction) of the tunnel and at the time of periodic inspection after construction. The three-dimensional measurement data of the measured wall surface is stored in a storage device within the data processing device 14 or an external storage device at the start of measurement and at the time of periodic inspection.

[0060] [Mechanism of Peeling of Surface Material of Building] FIG. 5 is a cross-sectional view of the vicinity of the surface of a building, showing an example of the mechanism by which the surface of a building peels off.

[0061] "(A) Normal state" in Figure 5 refers to a normal state such as during construction of a building. The surface in this state is the reference plane. In Figure 5, 40 denotes steel material (reinforcing bars).

[0062] The "(B) Cracks," "(C) Early stage of lifting / steel fracture," "(D) Final stage of lifting," and "(C) Peeling" in Figure 5 are caused by corrosion of the reinforcing bars 40 (e.g., salt damage or water leakage), and occur over time since the tunnel was constructed.

[0063] After "(C) Early stage of lifting / steel fracture" in Figure 5, the surface of the building gradually becomes higher than the reference level ("lifting" occurs), leading to the peeling of the cover concrete.

[0064] FIG. 6 is a cross-sectional view of the vicinity of the surface of a building, showing another example of the mechanism by which the surface of the building peels off.

[0065] "(A) Normal state" in Figure 6 refers to a normal state, such as during construction of a building. The surface in this state is taken as the reference surface. In Figure 6, 50 denotes reactive aggregate, and 60 denotes steel.

[0066] The "(B) Cracks," "(C) Early stage of lifting / steel fracture," "(D) Final stage of lifting," and "(C) Peeling" in Figure 5 are caused by deterioration of the concrete strength (e.g., alkali reaction of reactive aggregate 50), and occur over time since construction.

[0067] After "(C) Initial stage of lifting / steel fracture" in Figure 6, the surface of the building gradually becomes higher than the reference level ("lifting" occurs), leading to the peeling of the cover concrete from the surface of the steel 60 to the surface.

[0068] As shown in Figures 5 and 6, if the surface of a building changes over time and "lifting" occurs, "peeling" will occur in the future. This applies regardless of the cause of the "lifting." In other words, it does not matter whether there is reinforcing bars, their material, or shape, or the material and shape of the concrete, how the reinforcing bars are inserted into the concrete, the construction method, or the cause of corrosion (neutralization, frost damage, poor construction, etc.).

[0069] [Hardware Configuration of Peeling and Falling Identifying Device] FIG. 7 is a block diagram showing an embodiment of the hardware configuration of a peeling and falling identifying device according to the present invention.

[0070] 7 is configured, for example, by a personal computer, a workstation, or the like, and includes a processor 110, a memory 120, a display 130, an input / output interface 140, and an operation unit 150. This peeling and peeling identifying device 100 can be incorporated as one function of the data processing device 14 shown in FIG.

[0071] The processor 110 is composed of a CPU (Central Processing Unit) and the like, and controls each part of the peeling and delamination identification device 100, and executes a peeling and delamination identification program to perform various processes for identifying peeling and delamination parts on the surface of the building. Details of the various processes performed by the processor 110 will be described later.

[0072] The memory 120 includes a flash memory, a read-only memory (ROM), a random access memory (RAM), a hard disk drive, etc. The flash memory, ROM, or hard disk drive is a non-volatile memory that stores an operating system, various programs including the peeling and flake identification program according to the present invention, etc. Furthermore, the non-volatile memory (storage device) such as the flash memory or hard disk drive can store the 3D measurement data of the surface of the structure measured by the 3D measurement device 10 at the start of measurement of the structure and during periodic inspections, along with the measurement time.

[0073] The RAM functions as a working area for processing by the processor 110. It also temporarily stores various programs stored in flash memory or the like, and three-dimensional measurement data of the surface of a building. Note that the processor 110 may have part of the memory 120 (RAM) built in.

[0074] In addition to displaying a screen for operating the peeling and peeling identification device 100, the display device 130 displays the design surface data of the building read from the memory 120, or an image (including a panoramic composite image) of the building taken by one of the cameras of the stereo camera shown in Figure 4 or another imaging device not shown, and further displays the peeling and peeling parts identified by the peeling and peeling identification device 100 in an identifiable manner on the surface data or the image.

[0075] The input / output interface 140 includes a connection unit connectable to an external device, a communication unit connectable to a network, etc. As the connection unit connectable to an external device, a Universal Serial Bus (USB), a High-Definition Multimedia Interface (HDMI) (HDMI is a registered trademark), etc. can be applied.

[0076] The peeling and delamination identifying device 100 can be configured as a device independent of the data processing device 14. In this case, the processor 110 can acquire three-dimensional measurement data of the surface of the structure from the data processing device 14 via the input / output interface 140, or, if the three-dimensional measurement data is stored in the cloud, acquire the three-dimensional measurement data of the surface of the structure from the cloud via the input / output interface 140. The processor 110 can also store the three-dimensional measurement data acquired in this way in the memory 120.

[0077] The operation unit 150 includes a pointing device such as a mouse, a keyboard, and the like, and functions as part of a GUI (Graphical User Interface) that uses the display screen of the display device 130 and accepts instruction inputs by user operation.

[0078] FIG. 8 is a diagram showing a method for identifying peeled and fallen portions on the surface of a building.

[0079] FIG. 8A is a diagram showing the surface of a building and the scanning line of the laser light that scans the surface.

[0080] The three-dimensional measuring device 10 acquires three-dimensional measurement data (point cloud data) of a large number of measurement points on a scanning line of a laser beam.

[0081] The processor 110 compares the 3D measurement data of the structure surface with reference surface data that indicates a reference surface, and detects depressions in the structure surface. That is, by subtracting the reference surface data from the 3D measurement data, the processor 110 calculates height (unevenness) data of the structure surface on the scanning line of the laser light.

[0082] FIG. 8B is a waveform diagram showing the height of the surface of a building obtained from point cloud data on a scanning line.

[0083] As shown in Figure 8(B), the area where the height data is negative (the area lower than the reference surface) is the depression. The reference surface data indicating the reference surface can be defined in various ways, but it can be surface data obtained by averaging the unevenness of the surface of the structure indicated by the three-dimensional measurement data, or surface data in the design of the structure.

[0084] The processor 110 compares the depression detected as described above with a first threshold value (Th1) to determine whether the depression exceeds the first threshold value (Th1). The first threshold value (Th1) is preferably set to a value that can eliminate surface irregularities (depressions) that occur during construction of the building.

[0085] Next, the processor 110 determines whether the recessed portion exceeding the first threshold (Th1) is a peeled or flaked portion or a crack.

[0086] FIG. 9 is a captured image of a building including peeled and fallen portions and cracked portions.

[0087] The peeled and fallen portion shown in Fig. 9 includes a cracked portion. In addition, the captured image shown in Fig. 9 also includes a single cracked portion that is not included in the peeled and fallen portion.

[0088] FIG. 10 is a diagram showing an example of the surface texture of a building based on a large number of measurement points (measurement points distributed two-dimensionally) measured by a three-dimensional measuring device.

[0089] In Figure 10, of the measurement points shown in the point cloud, measurement points whose height data exceeds the first threshold (Th1) are shown with white circles, and measurement points whose height data is equal to or less than the first threshold (Th1) are shown with black circles.

[0090] In Figure 10, the measurement point indicated by the 7x1 white circle in the center corresponds to the crack, and the measurement point indicated by the 8x4 white circle to the left of it corresponds to the peeled and flaked part. The depression corresponding to this peeled and flaked part contains a crack.

[0091] The processor 110 identifies the recessed portion as a "peeling or peeling portion" (not a "crack") based on one or more of the following determination results:

[0092] (1) The width and length of the depression are measured, and if the shorter of the width and length exceeds a second threshold value (Th2), the depression is determined not to be a crack (it is a peeling or flaking portion).

[0093] The processor 110 detects regions of recessed portions exceeding the first threshold value (Th1) from height data of a large number of measurement points (measurement points distributed two-dimensionally) on a plurality of scanning lines by the measurement head of the three-dimensional measuring device 10. In the example shown in Fig. 10, the measurement points indicated by white circles exceed the first threshold value (Th1) as described above.

[0094] The processor 110 measures the width and height of a rectangle inscribed in a depression that exceeds a first threshold (Th1), and if the shorter of the width or height exceeds a second threshold (Th2), it determines that the depression is not a crack.

[0095] 10, the shorter width of the depression indicated by the 7x1 white circle measurement points corresponds to one measurement point, and is less than the second threshold (Th2), so the depression is determined to be a crack (not a peeling or flaking portion). The distance between adjacent measurement points can be determined in advance based on the measurement distance to the surface of the building, the scanning speed of the three-dimensional measurement device 10, etc.

[0096] On the other hand, the shorter width of the depression indicated by the 8x4 white circle measurement points is a width equivalent to four measurement points, and if the second threshold (Th2) is taken as a width equivalent to three measurement points, then the depression is determined not to be a crack (it is a peeling or flaking portion). Note that although the depression indicated by the 8x4 white circle measurement points includes a crack portion, this does not hinder the identification of the above-mentioned peeling or flaking portion.

[0097] FIG. 11 is a diagram showing another example of the surface texture of a building based on two-dimensional measurement points measured by a three-dimensional measuring device.

[0098] 11, the processor 110 measures the width (W) and height (H) of a depression (a rectangle inscribed in a group of points indicated by a white circle) that exceeds the first threshold (Th1). In the example shown in FIG. 11, the width (W) corresponds to the width of 12 measurement points, and the height (H) corresponds to the width of 10 measurement points.

[0099] If the shorter of the width (W) and the height (H) (in the example of Figure 11, the height (H)) exceeds the second threshold (Th2), the processor 110 determines that the depression is not a crack (it is a peeling or flaking portion).

[0100] (2) The area of ​​the depression is measured, and if the area exceeds a third threshold (Th3), the depression is identified as not being a crack (it is a peeling or flaking portion).

[0101] The processor 110 detects the area of ​​the depression portion that exceeds the first threshold value (Th1) in the same manner as above, and if the area of ​​the detected depression portion (corresponding to the number of points in the depression portion) exceeds the third threshold value (Th3), it determines that the depression portion is not a crack.

[0102] (3) An image of the building captured by the imaging device is acquired, cracks in the building are detected based on the captured image, and based on the crack detection results, the depressions are identified as not being cracks (they are peeling or flaking areas).

[0103] The processor 110 acquires captured images of the building taken by the imaging device and detects cracks in the building based on the captured images. If the crack detection results indicate that a depression is not a crack, the depression is identified as a peeled or flaked portion. On the other hand, if the depression is determined to be a crack, the depression can be determined not to be a peeled or flaked portion. Note that methods for detecting cracks from captured images are well known, and cracks can be detected more appropriately by using captured images with a higher resolution than 3D measurement data.

[0104] <Another Method for Detecting a Depression on the Surface of a Building> FIG. 12 is a diagram showing another method for detecting a depression on the surface of a building.

[0105] FIG. 12A is a diagram showing the surface of a building and the scanning line of the laser light that scans the surface, similar to FIG. 8A.

[0106] The three-dimensional measurement device 10 acquires three-dimensional measurement data of a large number of measurement points on the scanning line of the laser light. The memory 120 stores the three-dimensional measurement data of the surface of the structure measured by the three-dimensional measurement device 10 for each inspection of the structure.

[0107] Fig. 12(B) is a waveform diagram showing the height (h1) of the surface of the structure at a certain inspection time T1. The height (h1) of the surface of the structure shown in Fig. 12(B) is acquired based on the three-dimensional measurement data on the scanning line shown in Fig. 12(A) measured at the inspection time T1.

[0108] Fig. 12(C) is a waveform diagram showing the height (h2) of the surface of the structure at inspection time T2, which is later than inspection time T1. The height (h2) of the surface of the structure shown in Fig. 12(C) is obtained based on the three-dimensional measurement data on the scanning line shown in Fig. 12(A) measured at inspection time T2.

[0109] Figure 12 (D) is a waveform diagram showing the difference (h1-h2) at the same measurement point on the surface of a building, obtained by subtracting the height (h2) of the surface of the building at inspection time T2 shown in Figure 12 (C) from the height (h1) of the surface of the building at inspection time T1 shown in Figure 12 (B).

[0110] If the difference (h1-h2) is positive, the surface of the structure has become lower (depressed) by that difference (h1-h2) during the period from inspection time T1 to inspection time T2. Conversely, if the difference (h1-h2) is negative, the surface of the structure has become higher (risen) by that difference (h1-h2) during the period from inspection time T1 to inspection time T2.

[0111] The processor 110 can detect raised and depressed areas on the surface of the building by obtaining differential data for the same measurement point on the surface of the building based on multiple 3D measurement data measured during each inspection. In this example, the positive differential data can be used to detect depressed areas on the surface of the building.

[0112] It should be noted that among the different three-dimensional measurement data during inspection used to obtain the difference data, the three-dimensional measurement data early during inspection serves as reference surface data for the three-dimensional measurement data late during inspection.

[0113] <Other methods for identifying peeled and fallen portions> In the above embodiment, three-dimensional measurement data of the surface of a building is compared with reference surface data of the building to detect depressions on the surface of the building, and the properties of the detected depressions are analyzed to identify peeled and fallen portions on the surface of the building. However, the present invention is not limited to analyzing the properties of depressions, or it is also possible to analyze the properties of depressions and, at the same time, obtain difference data based on multiple three-dimensional measurement data of the surface of a building obtained during multiple (three or more) inspections, as shown below, and identify peeled and fallen portions from changes in this difference data.

[0114] When processor 110 detects raised portions and depressed portions in the same portion of the surface of the structure in the chronological order of inspection based on the difference data, it identifies the depressed portion as a peeled or flaked portion on the surface of the structure. In other words, if a raised portion on the surface of the structure is detected based on the difference data and the detected raised portion is then detected as a depressed portion, the depressed portion is identified as a peeled or flaked portion, because it is believed that the raised portion has peeled or flaked.

[0115] In addition, if the change in the differential data of multiple buildings turns negative (when the change in differential data when the surface of the building rises is positive and the change in differential data when the surface of the building sinks is negative, the processor 110 identifies the depressed area where the differential data turned negative as a peeled or flaked area on the surface of the building.

[0116] Furthermore, if the change in the differential data turns from positive to negative, or if the change in the differential data decreases beyond a threshold, the processor 110 can identify the depression corresponding to these changes in the differential data as a peeling or flaking portion on the surface of the building.

[0117] <Display of Peeling and Falling Off Portions> When the processor 110 identifies peeling and falling off portions on the surface of the building, the processor 110 displays the identified peeling and falling off portions on the screen of the display 130 so that the user can check them.

[0118] The processor 110 can display on the display 130 the measured three-dimensional measurement data, the design surface data of the building, or an image of the building captured by an imaging device, but it is preferable to display the identified peeled and flaked parts in an identifiable manner on the screen of the display 130 that displays these data or captured images.

[0119] FIG. 13 is a diagram showing an example of a screen of a display device on which peeled and fallen portions and the like are displayed.

[0120] On the screen of the display 130 shown in FIG. 13, the peeled and fallen portion (H) and the cracked portions (C1 to C5) are displayed superimposed on the captured image of the surface of the building.

[0121] The peeled and flaked portions (H) are displayed in a different brightness or color from the captured image of the surface of the building in the background, so that they can be easily identified by the user. The detected crack portions (C1 to C5) are also highlighted on the screen of the display 130, but the detection of the crack portions (C1 to C5) and the highlighting of the crack portions (C1 to C5) are not necessarily required. The captured image displayed on the display 130 may also be a panoramic image created by combining multiple captured images.

[0122] [Method for Identifying Peeling and Debris] FIG. 14 is a flowchart showing an embodiment of a method for identifying peeling and debriding according to the present invention.

[0123] The peeling / flake identifying method shown in FIG. 14 is a method performed by the processor 110 of the peeling / flake identifying device 100 shown in FIG.

[0124] 14, the processor 110 acquires the three-dimensional measurement data measured by the three-dimensional measurement device 10 (see FIG. 3) for each inspection of the building (step S10). The processor 110 may acquire the three-dimensional measurement data from the storage device of the data processing device 14, the cloud, etc., or from the memory 120 of the peeling and delamination identifying device 100.

[0125] The processor 110 compares the 3D measurement data with the reference surface data of the building to detect recesses on the surface of the building (step S20). 3D measurement data that is lower in height than the reference surface data can be detected as data on recesses.

[0126] Next, the processor 110 determines whether the depression detected in step S20 is depressed to a degree exceeding a first threshold (step S30), in order to distinguish it from a depression that exists from the time of construction (a depression caused by slight irregularities).

[0127] If it is determined that the recessed portion is recessed beyond the first threshold value (if "Yes"), the process proceeds to step S40, and if it is determined that the recessed portion is not recessed beyond the first threshold value (if "No"), the recessed portion is determined to not be a peeled or flaked portion, and the determination of the surface properties for that recessed portion is terminated.

[0128] In step S40, the processor 110 determines whether a recessed portion that is recessed beyond the first threshold is a crack. Specifically, the processor 110 determines whether the recessed portion is a peeled or flaked portion or a cracked portion by the following process.

[0129] (1) The width and length of the depression are measured, and if the shorter of the width and length exceeds a second threshold value (Th2), the depression is determined not to be a crack.

[0130] (2) The area of ​​the depression is measured, and if the area exceeds a third threshold (Th3), the depression is determined not to be a crack.

[0131] (3) An image of the building captured by the imaging device is acquired, cracks in the building are detected based on the captured image, and based on the crack detection results, it is determined that the depression is not a crack.

[0132] If it is determined in step S40 that the depression is not a crack ("No"), the processor 110 identifies the depression as a peeling or flaking portion of the surface of the building (step S50).

[0133] The processor 110 notifies the user of the identified peeled and fallen portion on the surface of the building (step S60). For example, the processor 110 displays the identified peeled and fallen portion (H) in an identifiable manner on the screen of the display 130 that displays the surface of the building (see FIG. 13 ).

[0134] This allows inspectors to easily check for peeling and falling areas on the surface of concrete or other materials on buildings.

[0135] [Others] The structure in this embodiment is a tunnel, but is not limited to this and may be any structure that is inspected, such as a bridge or a dam. The surface material of the structure includes reinforced concrete, concrete, and concrete repair materials such as mortar.

[0136] In this embodiment, the hardware structure of a processing unit that executes various processes, such as a CPU (Central Processing Unit), is various processors as shown below. The various processors include a CPU, which is a general-purpose processor that executes software (programs) to function as various processing units, a programmable logic device (PLD), such as an FPGA (Field Programmable Gate Array), whose circuit configuration can be changed after manufacture, and a dedicated electrical circuit, such as an ASIC (Application Specific Integrated Circuit), which is a processor with a circuit configuration designed specifically for executing specific processes.

[0137] A single processing unit may be configured with one of these various processors, or may be configured with two or more processors of the same or different types (e.g., multiple FPGAs, or a combination of a CPU and an FPGA). Multiple processing units may also be configured with a single processor. Examples of multiple processing units configured with a single processor include: a first configuration, as typified by client or server computers, in which a single processor is configured with a combination of one or more CPUs and software, and this processor functions as multiple processing units; and a second configuration, as typified by system-on-chip (SoC), in which a processor is used to realize the functions of an entire system including multiple processing units on a single IC (Integrated Circuit) chip. In this way, the various processing units are configured with one or more of the above-mentioned various processors as a hardware structure.

[0138] Furthermore, the hardware structure of these various processors is, more specifically, an electric circuit made up of a combination of circuit elements such as semiconductor elements.

[0139] Furthermore, the present invention includes a peeling and peeling identification program that, when installed on a computer, causes the computer to function as the peeling and peeling identification device of the present invention, and a non-volatile storage medium on which this peeling and peeling identification program is recorded.

[0140] Furthermore, it goes without saying that the present invention is not limited to the above-described embodiment, and various modifications are possible within the scope of the present invention.

[0141] REFERENCE SIGNS LIST 10...3D measuring device 12...Tripod 14...Data processing device 16...Power supply device 18...Cart 20...Wall surface 30L...Left camera 30R...Right camera 40...Reinforcing bar 50...Reactive aggregate 60...Steel material 100...Skinning and peeling identification device 110...Processor 120...Memory 130...Display 140...Input / output interface 150...Operation unit S10 to S60...Steps

Claims

1. A peeling and delamination identification device comprising a processor and a memory for storing a program to be executed by the processor, wherein the processor: acquires three-dimensional measurement data of the surface of a structure measured by a measuring device; compares the three-dimensional measurement data with reference surface data of the structure to detect a depression in the surface of the structure; and if the depression is determined to be a depression exceeding a first threshold value and is not a crack, identifies the depression as a peeling and delamination portion on the surface of the structure.

2. The peeling / flaking identification device of claim 1, wherein the processor measures the width and height of the recessed portion, and if the shorter of the width or height exceeds a second threshold value, determines that the recessed portion is not a crack.

3. The peeling / flaking identification device according to claim 1, wherein the processor measures an area of ​​the recessed portion, and if the area exceeds a third threshold value, determines that the recessed portion is not a crack.

4. The peeling and falling off identification device as described in claim 1, wherein the processor acquires an image of the structure captured by an imaging device, detects cracks in the structure based on the image, and determines whether the depression is a crack or not based on the crack detection result.

5. A peeling and falling off identification device as described in any one of claims 1 to 4, wherein the reference surface data is surface data obtained by averaging the unevenness of the surface of the structure indicated by the three-dimensional measurement data, or surface data based on the design of the structure.

6. The peeling and falling identification device described in claim 1, wherein the memory stores three-dimensional measurement data of the surface of the structure measured by the measuring device each time the structure is inspected, and the processor acquires a plurality of three-dimensional measurement data of the surface of the structure measured each time the structure is inspected, acquires difference data of the same measurement point on the surface of the structure based on the plurality of three-dimensional measurement data, and detects at least the recessed portions of the raised portions and recessed portions of the surface of the structure based on the difference data.

7. The peeling and flaking identification device according to claim 6, wherein when the processor detects the raised portion and the depressed portion in the same part of the surface of the structure in the chronological order of the inspection, it identifies the depressed portion as a peeled and flaked portion of the surface of the structure.

8. The peeling and peeling identification device of claim 6, wherein the processor identifies the recessed portion as a peeling and peeling portion of the surface of the structure when the change in the difference data turns negative, when the change in the difference data turns from positive to negative, or when the change in the difference data decreases beyond a threshold value.

9. The peeling and peeling identification device described in claim 1, wherein the processor causes the identified peeling and peeling parts to be identifiable on a screen of a display that displays the three-dimensional measurement data, the design surface data of the building, or an image of the building captured by an imaging device.

10. The peeling and falling identification device according to claim 1, wherein the measuring device includes a LiDAR or a stereo camera.

11. The peeling and falling off identification device according to claim 10, wherein the LiDAR measures the three-dimensional measurement data using a Frequency Modulated Continuous Wave (FMCW) method.

12. The peeling and falling off identification device according to claim 1, wherein the material of the surface of the building structure includes concrete or a concrete repair material.

13. A peeling and spalling identification method in which a processor identifies peeling and spalling on the surface of a structure, the method comprising: acquiring three-dimensional measurement data of the surface of a structure measured by a measuring device; comparing the three-dimensional measurement data with reference surface data of the structure to detect a depression in the surface of the structure; and, if the depression is determined to be a depression exceeding a first threshold value and is not a crack, identifying the depression as a peeling and spalling portion on the surface of the structure.

14. The method for identifying peeling and falling off described in claim 13, wherein the processor measures the width and length of the depression portion, and if the shorter of the width or length exceeds a second threshold value, determines that the depression portion is not a crack.

15. The method for identifying peeling and spalling according to claim 13, wherein the processor measures an area of ​​the recessed portion, and if the area exceeds a third threshold value, determines that the recessed portion is not a crack.

16. The peeling and falling off identification method described in claim 13, wherein the processor acquires an image of the structure captured by an imaging device, detects cracks in the structure based on the image, and determines whether the depression is a crack or not based on the crack detection result.

17. A peeling and flaking identification program for identifying peeling and flaking on the surface of a structure, the program causing a computer to execute the following functions: acquiring three-dimensional measurement data of the surface of the structure measured by a measuring device; comparing the three-dimensional measurement data with reference surface data of the structure to detect a depression on the surface of the structure; and, if the depression is determined to be a depression exceeding a first threshold value and is not a crack, identifying the depression as a peeling and flaking portion on the surface of the structure.

18. A non-transitory computer-readable recording medium having the program according to claim 17 recorded thereon.

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