Imaging system and imaging method

Abstract

To detect a deterioration state of an object to be inspected, with high accuracy.SOLUTION: An imaging system 100 includes: a first camera 120 which generates a first image; an index synthesizing unit which converts index information to be synthesized with the first image so that a plurality of first imaginary points included in the index information indicating the first imaginary points that define imaging ranges may be included within an inspection range on the first image; laser irradiation units 142; an irradiation displacement unit (moving apparatus 110, irradiation unit displacement mechanism 144) for displacing the laser irradiation units so that irradiation points irradiated by the laser irradiation units may be coincident with the first imaginary points defining one imaging range, on the first image with the index information synthesized thereon; and a camera position changing unit (moving apparatus 110, camera position changing mechanism 134) which displaces or rotates the second camera so that a plurality of second imaginary points defining imaging ranges may be coincident with the irradiation points, respectively, the imaginary points being set in advance on a second image generated by the second camera 132.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to an imaging system and an imaging method. [Background technology]

[0002] Technologies have been developed to inspect the deterioration state of structures by capturing images of the surfaces of structures such as bridges, highways, tunnels, dams, and buildings and analyzing the images obtained.

[0003] For example, Patent Document 1 discloses a technology in which an image obtained by capturing the surface of a structure is subjected to image processing to generate a normalized image, and the normalized image is analyzed to detect cracks in the structure. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2017-34576 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the conventional technology described in Patent Document 1, a portion of an image is enlarged or reduced by orienting the image. As a result, the orientated image includes areas where the size is unchanged, areas where the size is enlarged, and areas where the size is reduced. As a result, the resolution (the number of pixels contained per unit area) differs between the areas where the size is unchanged, the enlarged areas, and the reduced areas. For this reason, in the conventional technology, the accuracy of detecting the deterioration state varies in each area of ​​the orientated image. Therefore, the conventional technology has a problem in that the accuracy of detecting the deterioration state of the object to be inspected is low.

[0006] In view of the above problems, the present disclosure aims to provide an imaging system and an imaging method that are capable of detecting the deterioration state of an inspection object with high accuracy. [Means for solving the problem]

[0007] In order to solve the above problem, an imaging system according to one embodiment of the present disclosure includes: a first camera that captures an inspection range on an inspection surface of an object to be inspected and generates a first image; an index synthesis unit that converts index information indicating a plurality of first virtual points that define one or more imaging ranges and synthesizes the index information with the first image so that a plurality of first virtual points included in the index information are included within the inspection range on the first image; a laser irradiation unit that irradiates the inspection surface with laser light; an irradiation displacement unit that displaces each laser irradiation unit so that, on the first image into which the index information has been synthesized, each irradiation point of the laser light from each laser irradiation unit coincides with a plurality of first virtual points that define one imaging range; a second camera that captures an inspection range and generates a second image; and a camera position change unit that displaces or rotates the second camera so that a plurality of second virtual points that are preset on the second image and that define the imaging range coincide with each irradiation point.

[0008] In order to solve the above problem, another imaging system according to one embodiment of the present disclosure includes a first camera that captures an inspection range on an inspection surface of an object to be inspected and generates a first image; an index synthesis unit that converts index information indicating a plurality of first virtual points that define one or more imaging ranges and synthesizes the index information with the first image so that a plurality of first virtual points included in the index information are included within the inspection range on the first image; a laser irradiation unit that irradiates laser light onto the inspection surface; a second camera that captures an inspection range and generates a second image; a holding unit that integrally holds the laser irradiation unit and the second camera; and an imaging position change unit that displaces or rotates the holding unit so that, on the first image into which the index information has been synthesized, each of the irradiation points of the laser light from each laser irradiation unit coincides with a plurality of first virtual points that define one imaging range, and so that each of the irradiation points coincides with a plurality of second virtual points that are preset on the second image and that define the imaging range.

[0009] The second camera may also be a near-infrared camera or an infrared camera.

[0010] In order to solve the above problem, an imaging method according to one embodiment of the present disclosure is an imaging method that uses a first camera that images an inspection range on an inspection surface of an object to be inspected and generates a first image, a laser irradiation unit that irradiates the inspection surface with laser light, and a second camera that images the inspection range and generates a second image, and includes: a process of converting index information indicating a plurality of first virtual points that define one or more imaging ranges and combining the index information with the first image so that a plurality of first virtual points included in the index information are included within the inspection range on the first image; a process of displacing each laser irradiation unit so that, on the first image combined with the index information, each irradiation point of laser light from each laser irradiation unit coincides with a plurality of first virtual points that define one imaging range; and a process of displacing or rotating the second camera so that a plurality of second virtual points that are preset on the second image and that define the imaging range coincide with each irradiation point.

[0011] In order to solve the above problem, another imaging method according to one embodiment of the present disclosure is an imaging method using a first camera that captures an inspection range on an inspection surface of an object to be inspected and generates a first image, a laser irradiation unit that irradiates the inspection surface with laser light, a second camera that captures an inspection range and generates a second image, and a holding unit that integrally holds the laser irradiation unit and the second camera, the imaging method including: a process of converting index information indicating a plurality of first virtual points that define one or more imaging ranges and combining the index information with the first image so that a plurality of first virtual points included in the index information are included within the inspection range on the first image; and a process of displacing or rotating the holding unit so that, on the first image combined with the index information, each of the irradiation points of the laser light from each laser irradiation unit coincides with a plurality of first virtual points that define one imaging range, and a plurality of second virtual points that are preset on the second image and that define the imaging range coincide with each of the irradiation points. [Effects of the Invention]

[0012] According to the present disclosure, it is possible to detect the deterioration state of an inspection object with high accuracy. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a diagram illustrating an outline of an imaging system according to this embodiment. [Figure 2] FIG. 2 is a diagram illustrating an image of the relative positional relationship between the first camera, the second camera, and the laser irradiation unit. [Figure 3] FIG. 3 is a diagram illustrating an image of the first image. [Figure 4] FIG. 4 is a functional block diagram of the control device. [Figure 5] FIG. 5 is a diagram illustrating the index information. [Figure 6] FIG. 6 is a diagram illustrating the processing performed by the imaging range setting unit. [Figure 7] FIG. 7 is a diagram illustrating the processing performed by the index synthesis unit. [Figure 8] FIG. 8 is a diagram illustrating the processing performed by the irradiation position control unit. [Figure 9] FIG. 9 is a diagram illustrating the processing performed by the camera position control unit. [Figure 10] FIG. 10 is a diagram illustrating the processing of the image integration unit. [Figure 11] FIG. 11 is a flowchart showing the processing flow of the imaging method according to this embodiment. [Figure 12] FIG. 12 is a diagram illustrating an outline of an imaging system according to a modified example. [Figure 13] FIG. 13 is a diagram illustrating the holding portion. [Figure 14] FIG. 14 is a functional block diagram of a control device according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. Dimensions, materials, and other specific numerical values ​​shown in the embodiments are merely examples for ease of understanding and do not limit the present disclosure unless otherwise specified. In this specification and drawings, elements having substantially the same functions and configurations are designated by the same reference numerals to avoid redundant explanation, and elements not directly related to the present disclosure are not shown.

[0015] [Imaging system 100] Fig. 1 is a diagram illustrating an outline of an imaging system 100 according to this embodiment. Fig. 2 is a diagram illustrating an image of the relative positional relationship between a first camera 120, a second camera 132, and a laser irradiation unit 142.

[0016] As shown in FIG. 1, an imaging system 100 captures an image of an inspection surface 12 of an inspection object 10 and inspects the inspection surface 12. In this embodiment, a bridge is taken as an example of the inspection object 10, but the inspection object 10 is not limited to this. The inspection object 10 may also be a structure other than a bridge, such as a highway, a tunnel, a dam, or a building. In addition, a case where the inspection surface 12 is the underside of the inspection object 10 will be taken as an example.

[0017] The imaging system 100 includes a moving device 110 , a first camera 120 , a second camera unit 130 , a plurality of illumination units 140 , and a control device 150 .

[0018] The moving device 110 (illumination displacement unit, camera position change unit) includes a base unit 112, an elevation unit 114, a moving unit 116, and an installation plate 118.

[0019] The base portion 112 is disposed below the inspection object 10 .

[0020] The lifting unit 114 is provided from above the inspection object 10 to below the inspection object 10. The lifting unit 114 lifts and lowers the base unit 112 in the up and down direction.

[0021] The moving part 116 is provided on the base part 112. An installation plate 118 is provided at the tip of the moving part 116. The moving part 116 moves the installation plate 118 in the horizontal direction.

[0022] The first camera 120 is provided on the base unit 112. The first camera 120 generates a first image 210. The first camera 120 captures an inspection range 20 on the inspection surface 12. For example, the first camera 120 captures the entire inspection range 20. The inspection range 20 is a partial range of the inspection surface 12. The inspection range 20 is set in advance by an inspector using the imaging system 100. In FIG. 1, the dashed line indicates the range of the inspection surface 12 captured by the first camera 120. The first camera 120 is, for example, a visible light camera.

[0023] Fig. 3 is a diagram illustrating an image of the first image 210. As shown in Fig. 3, the first image 210 includes the entire inspection range 20 (shown by hatching in Fig. 3).

[0024] 1, the second camera unit 130 is provided on the installation plate 118. The second camera unit 130 includes a second camera 132 and a camera position changing mechanism 134.

[0025] The second camera 132 generates a second image 220. The second camera 132 captures an inspection range 20 on the inspection surface 12. In this embodiment, the second camera 132 captures a portion of the inspection range 20. For example, the range of the inspection surface 12 captured by the second camera 132 is narrower than that of the first camera 120. In FIG. 1, the dashed dotted line indicates the range of the inspection surface 12 captured by the second camera 132. The second camera 132 is, for example, a visible light camera.

[0026] In the imaging system 100 according to this embodiment, the deterioration state of the inspection area 20 is inspected based on the second image 220 generated by the second camera 132 capturing an image of a portion of the inspection area 20. The deterioration state may be cracks, paint cracks, salt concentration, etc. For example, the imaging system 100 compares the second image 220 including a portion of the inspection area 20 with multiple calibration images. The calibration image is an image that includes feature points that indicate the deterioration state. The multiple calibration images are acquired in advance by capturing images of test objects in different degrees of deterioration.

[0027] The camera position changing mechanism 134 (camera position changing unit) changes the position and angle of the second camera 132 in the up and down direction.

[0028] A plurality of irradiation units 140 are provided on an installation plate 118. In this embodiment, the number of irradiation units 140 provided is the same as the number of first virtual points (four in this embodiment) that define one imaging range, which will be described later. Each irradiation unit 140 includes a laser irradiation section 142 and an irradiation section displacement mechanism 144.

[0029] The laser irradiation unit 142 irradiates laser light onto the inspection surface 12. The laser irradiation unit 142 is configured by, for example, a laser pointer.

[0030] The irradiation unit displacement mechanism 144 (irradiation displacement unit) changes the angle of the laser irradiation unit 142.

[0031] 4 is a functional block diagram of the control device 150. The control device 150 includes a central control unit 152, a display unit 154, and a memory 156.

[0032] The central control unit 152 is configured by a semiconductor integrated circuit including a CPU (Central Processing Unit). The central control unit 152 reads programs, parameters, etc. for operating the CPU from the ROM. Based on the programs, parameters, etc., the central control unit 152 manages and controls the entire control device 150 in cooperation with RAM as a work area and other electronic circuits.

[0033] The display unit 154 is configured with a liquid crystal display, an organic EL (Electro Luminescence) display, etc. In this embodiment, the display unit 154 displays a first image 210, a second image 220, index information 230 (described later), and the like.

[0034] The memory 156 is composed of a ROM, a RAM, a flash memory, a HDD, etc. The memory 156 stores programs and various data used by the central control unit 152. For example, the memory 156 holds index information 230, virtual point information, identification information, a calibration image, etc., which will be described later.

[0035] In this embodiment, the central control unit 152 functions as an index generation unit 170, an imaging range setting unit 172, a first imaging control unit 174, a position determination unit 176, an index synthesis unit 178, an irradiation position control unit 180, a second imaging control unit 182, a camera position control unit 184, an image integration unit 186, and a comparison unit 188.

[0036] The index generating unit 170 generates index information. The index information is information indicating a plurality of first virtual points that define one or a plurality of imaging ranges. The index information is generated based on, for example, a design drawing of the inspection object 10.

[0037] Fig. 5 is a diagram illustrating index information 230. As shown in Fig. 5, index information 230 includes outer edge information 232 and a plurality of first imaginary points PA. The outer edge information 232 is information that indicates the outer edge of the inspection range 20. The first imaginary points PA are information that define a plurality of imaging ranges R that are assigned to the inspection range 20. Here, one imaging range R is defined by four first imaginary points PA.

[0038] In this embodiment, the size of the imaging range R is set so that the area of ​​the test piece included in the imaging range when the calibration image is acquired and the area of ​​the inspection range 20 included in the imaging range R are approximately equal.

[0039] 5, 18 first imaginary points PA define 10 imaging ranges R. That is, the index information 230 shown in FIG. 5 indicates 18 first imaginary points PA that define the 10 imaging ranges R.

[0040] The index information 230 generated by the index generating unit 170 is stored in the memory 156 .

[0041] The imaging range setting unit 172 sets a plurality of second virtual points that define the imaging range R on the second image 220 generated by the second camera 132.

[0042] Fig. 6 is a diagram illustrating processing by the imaging range setting unit 172. As shown in Fig. 6, in this embodiment, the imaging range setting unit 172 sets four second imaginary points PB on the second image 220. The four second imaginary points PB are set at positions corresponding to the four corners of the second image 220, for example. One imaging range R is virtually set by the four second imaginary points PB.

[0043] The memory 156 holds virtual point information that indicates the plurality of second virtual points PB, which is generated by the imaging range setting unit 172.

[0044] The first imaging control unit 174 controls the first camera 120 to generate the first image 210 .

[0045] The position determination unit 176 controls the moving device 110 so that the entire inspection range 20 is imaged by the first camera 120. Specifically, the position determination unit 176 controls the lifting / lowering unit 114 to move the position of the base unit 112 (first camera 120) so that the entire inspection range 20 is imaged by the first camera 120. Then, the position determination unit 176 stops driving the lifting / lowering unit 114 when the entire inspection range 20 is positioned so that it can be imaged by the first camera 120. This causes the first camera 120 to be fixed at a predetermined position.

[0046] The index combining unit 178 converts the index information 230 so that the inspection range 20 on the first image 210 includes a plurality of first virtual points PA, and combines (superimposes) the converted index information with the first image 210.

[0047] 7 is a diagram illustrating processing by the index combining unit 178. As shown in Fig. 7, the index combining unit 178 converts the index information 230 so that all of the first virtual points PA included in the index information 230 are included in the inspection range 20 on the first image 210. For example, the index combining unit 178 converts the index information 230 so that the position of the outer edge of the inspection range 20 on the first image 210 matches the position of the outer edge information 232 included in the index information 230.

[0048] The irradiation position control unit 180 (irradiation displacement unit) controls the moving device 110 and the irradiation unit displacement mechanism 144 to displace the irradiation point of the laser light from the laser irradiation unit 142.

[0049] Fig. 8 is a diagram illustrating processing by the irradiation position control unit 180. As indicated by the arrows in Fig. 8, the irradiation position control unit 180 displaces each laser irradiation unit 142 so that the irradiation points PL of each laser irradiation unit 142 coincide with four first virtual points PA that form one imaging range R on the first image 210 onto which the index information 230 has been combined.

[0050] The second imaging control unit 182 controls the second camera 132 to generate a second image 220.

[0051] The camera position control unit 184 (camera position changing unit) controls the moving device 110 and the camera position changing mechanism 134 to displace and rotate the second camera 132.

[0052] FIG. 9 is a diagram illustrating the processing performed by the camera position control unit 184. The camera position control unit 184 first displaces the second camera 132 so that the center C of the second image 220 captured by the second camera 132 is included within a virtual figure SL. The virtual figure SL is a virtual figure formed by a plurality of illuminated points PL. Then, as indicated by the arrows in FIG. 9, the camera position control unit 184 displaces and rotates the second camera 132 so that a plurality of second virtual points PB on the second image 220, which have been preset using the virtual point information stored in the memory 156, coincide with the illuminated points PL, respectively.

[0053] Then, when the plurality of second imaginary points PB on the second image 220 coincide with the respective irradiation points PL, the second imaging control unit 182 controls the second camera 132 to generate the second image 220. The second imaging control unit 182 also associates identification information with the generated second image 220 and stores the information in the memory 156. The identification information indicates a position in the index information 230 that corresponds to the generated second image 220.

[0054] The image integration unit 186 references the identification information and integrates a plurality of second images 220 including a portion of the inspection range 20 to generate an integrated image. Fig. 10 is a diagram illustrating the processing of the image integration unit 186. As shown in Fig. 10, the image integration unit 186 references the index information 230 and the identification information to integrate the second images 220.

[0055] The comparison unit 188 compares the integrated image with the calibration image to determine the degree of deterioration of the inspection area 20 .

[0056] [Image capture method] Next, an imaging method using the imaging system 100 will be described. Fig. 11 is a flowchart showing the processing flow of the imaging method according to this embodiment. As shown in Fig. 11, the imaging method according to this embodiment includes a positioning process S110, a first image generation process S112, an index information synthesis process S114, an initial setting process S116, an end determination process S118, an irradiation unit displacement process S120, a second camera position control process S122, a second image generation process S124, an increment process S126, a second image integration process S128, and a comparison process S130. Each process will be described below.

[0057] [Positioning process S110] The position determination unit 176 controls the moving device 110 so that the entire inspection range 20 set in advance on the inspection surface 12 is captured by the first camera 120. Then, when the position determination unit 176 reaches a position where the entire inspection range 20 is captured by the first camera 120, it fixes the first camera 120 at that position.

[0058] [First image generation process S112] The first imaging control unit 174 controls the first camera 120 to generate the first image 210 .

[0059] [Index information synthesis process S114] The index combining unit 178 combines the first image 210 generated in the first image generation process S112 with the index information 230 held in the memory 156. In the present embodiment, the index combining unit 178 converts the index information 230 and combines it with the first image 210 so that all of the first virtual points PA included in the index information 230 are included in the inspection range 20 on the first image 210.

[0060] [Initial setting process S116] The central control unit 152 sets the counter value n of the counter that counts the number of second images 220 to 1.

[0061] [End determination process S118] The central control unit 152 determines whether the counter value n is N. N is the total number of imaging ranges R included in the index information 230. In the example shown in FIG. 5, N is 10. When the central control unit 152 determines that the counter value n is N (YES in S118), the central control unit 152 shifts the process to a second image integration process S128. On the other hand, when the central control unit 152 determines that the counter value n is not N (NO in S118), the central control unit 152 shifts the process to an irradiation unit displacement process S120.

[0062] [Irradiation unit displacement processing S120] The irradiation position control unit 180 controls the moving device 110 and the irradiation unit displacement mechanism 144 to displace each laser irradiation unit 142. In this embodiment, the irradiation position control unit 180 displaces each laser irradiation unit 142 so that each irradiation point PL by each laser irradiation unit 142 coincides with a plurality of first virtual points PA that define one imaging range R on the first image 210 onto which the index information 230 has been combined.

[0063] Furthermore, the central control unit 152 generates, as identification information, information indicating the position on the index information 230 of the imaging range R defined by the plurality of first imaginary points PA that are to coincide with the irradiation point PL.

[0064] [Second camera position control process S122] Camera position control unit 184 controls moving device 110 and camera position changing mechanism 134 to displace and rotate second camera 132. In this embodiment, camera position control unit 184 displaces and rotates second camera 132 so that a plurality of second imaginary points PB set in advance on second image 220 coincide with each of irradiation points PL.

[0065] [Second image generation process S124] The second imaging control unit 182 controls the second camera 132 to generate the second image 220 at the position determined in the second camera position control process S122. Then, the second imaging control unit 182 associates the generated second image 220 with the identification information generated in the irradiation unit displacement process S120 and stores the association information in the memory 156.

[0066] [Increment process S126] The central control unit 152 increments the counter value n.

[0067] [Second image integration process S128] When the central control unit 152 determines that the counter value n is N (YES in S118), the image integration unit 186 references the identification information and integrates the plurality of second images 220 to generate an integrated image.

[0068] [Comparison process S130] The comparison unit 188 compares each of the second images 220 included in the integrated image with the calibration image. As a result, if there is a second image 220 that includes a portion where the degree of deterioration exceeds a predetermined threshold, the comparison unit 188 identifies the position of the second image 220 in the integrated image.

[0069] As described above, the imaging system 100 according to this embodiment and the imaging method using the same include the index combining unit 178. As described above, the index information 230 indicates a plurality of first virtual points PA that define one or more imaging ranges R. The index combining unit 178 then converts the index information 230 and combines it with the first image 210 so that all of the first virtual points PA included in the index information 230 are included in the inspection range 20 on the first image 210. This allows the imaging system 100 to appropriately assign one or more imaging ranges R included in the index information 230 to the inspection range 20 on the first image 210.

[0070] The imaging system 100 also includes an irradiation displacement unit (moving device 110, irradiation unit displacement mechanism 144, irradiation position control unit 180) and a camera position change unit (moving device 110, camera position change mechanism 134, camera position control unit 184). As described above, the irradiation displacement unit aligns the irradiation points of the laser irradiation unit 142 with a plurality of first imaginary points PA that are assigned to the inspection range 20 on the first image 210 and define the imaging range R. The camera position change unit then displaces or rotates the second camera 132 so that a plurality of second imaginary points PB that are set in advance on the second image 220 and define the imaging range R align with the irradiation points PL, respectively. This allows the imaging system 100 to position the second camera 132 directly facing the inspection range 20 (inspection surface 12). Therefore, the second camera 132 can generate the second image 220 while facing the inspection range 20 directly.

[0071] In conventional techniques for inspecting the state of deterioration using a normalized image obtained by normalizing an image, a portion of the image is enlarged or reduced. As a result, the normalized image includes areas whose size remains unchanged, areas that have been enlarged, and areas that have been reduced. In the normalized image, the resolution differs between the areas. As a result, in conventional techniques, the accuracy of detecting the state of deterioration varies between the areas of the normalized image. Therefore, the conventional techniques have a problem of low accuracy in detecting the state of deterioration.

[0072] In contrast, the imaging system 100 can generate the second image 220 in a state facing the inspection area 20. Therefore, the imaging system 100 does not need to perform a facing process on the second image 220. Therefore, the imaging system 100 can make the resolution of the entire second image 220 substantially uniform. This enables the imaging system 100 to detect the deterioration state of the inspection object 10 with higher accuracy than conventional techniques.

[0073] [Modification: Imaging System 300] In the above embodiment, the case where second camera 132 and laser irradiation unit 142 are displaced independently has been described as an example. However, second camera 132 and laser irradiation unit 142 may be displaced integrally.

[0074] Fig. 12 is a diagram illustrating an outline of an imaging system 300 according to a modified example. As shown in Fig. 12, the imaging system 300 includes a moving device 110 (imaging position change unit), a first camera 120, an imaging unit 310, and a control device 350. Note that components that are substantially the same as those in the imaging system 100 described above are given the same reference numerals and descriptions thereof will be omitted.

[0075] The imaging unit 310 includes a second camera 132, a plurality of laser irradiation sections 142, a holding section 320, and a displacement mechanism 330 (imaging position change section).

[0076] The holder 320 integrally holds the second camera 132 and the plurality of laser irradiation units 142. FIG. 13 is a diagram illustrating the holder 320. As shown in FIG. 13, the holder 320 includes a frame 322 and a support 324. The frame 322 is a rectangular frame. The plurality of laser irradiation units 142 are fixed to the frame 322. The frame 322 holds the plurality of laser irradiation units 142 so that the positional relationship between the plurality of laser irradiation units 142 is approximately equal to the positional relationship between the plurality of first virtual points PA that define the imaging range R, for example. The support 324 fixes the second camera 132 to the frame 322. In a modified example, the support 324 fixes the second camera 132 to approximately the center of the frame 322.

[0077] Fig. 14 is a functional block diagram of a control device 350 according to a modified example. As shown in Fig. 14, the control device 350 includes a central control unit 352, a display unit 154, and a memory 156. In the modified example, the central control unit 352 functions as an index generation unit 170, an imaging range setting unit 172, a first imaging control unit 174, a position determination unit 176, an index synthesis unit 178, a position control unit 380, a second imaging control unit 182, an image integration unit 186, and a comparison unit 188.

[0078] Position control unit 380 (imaging position change unit) controls moving device 110 and displacement mechanism 330 to displace holding unit 320. Position control unit 380 displaces and rotates holding unit 320 so that, on first image 210 onto which index information 230 has been combined, irradiation points PL by each laser irradiation unit 142 coincide with a plurality of first imaginary points PA that define one imaging range R, and so that a plurality of second imaginary points PB set in advance on second image 220 coincide with the irradiation points PL, respectively.

[0079] As described above, the imaging system 300 according to the modified example can make the second camera 132 face the inspection range 20 (inspection surface 12).

[0080] Although the embodiments have been described above with reference to the accompanying drawings, it goes without saying that the present disclosure is not limited to the above-described embodiments. It is clear that a person skilled in the art can conceive of various modifications or alterations within the scope of the claims, and it is understood that these also naturally fall within the technical scope of the present disclosure.

[0081] For example, in the above-described embodiment, the irradiation units 140 are provided on the installation plate 118. However, the irradiation units 140 may be provided on the base portion 112. Furthermore, some of the irradiation units 140 may be provided on the installation plate 118, and other irradiation units 140 may be provided on the base portion 112.

[0082] Furthermore, in the above embodiment and modified examples, the central control unit 152, 352 functions as the first imaging control unit 174. However, the central control unit 152, 352 does not have to function as the first imaging control unit 174. In this case, the first camera 120 may generate the first image 210 in response to an operation input by the inspector.

[0083] Similarly, the case where the central control unit 152, 352 functions as the second imaging control unit 182 has been described as an example. However, the central control unit 152, 352 does not have to function as the second imaging control unit 182. In this case, the second camera 132 may generate the second image 220 in response to an operation input by the inspector.

[0084] The index generating unit 170 may generate index information 230 in response to an operation input by the inspector. Similarly, the imaging range setting unit 172 may set multiple second virtual points PB that define an imaging range R on the second image 220 in response to an operation input by the inspector. The position determining unit 176 may control the moving device 110 in response to an operation input by the inspector so that the entire inspection range 20 is captured by the first camera 120. The index combining unit 178 may convert the index information 230 and combine it with the first image 210 in response to an operation input by the inspector. The irradiation position control unit 180 may control the moving device 110 and the irradiation unit displacement mechanism 144 in response to an operation input by the inspector to displace each laser irradiation unit 142 so that the irradiation points PL of each laser irradiation unit 142 coincide with four first virtual points PA that define one imaging range R on the first image 210 on which the index information 230 has been combined. Furthermore, camera position control unit 184 may control moving device 110 and camera position changing mechanism 134 in response to an operation input by the inspector, and displace or rotate second camera 132 so that a plurality of second virtual points PB set in advance on second image 220 coincide with each of irradiation points PL. Furthermore, position control unit 380 may control moving device 110 and displacement mechanism 330 in response to an operation input by the inspector, and displace or rotate holding unit 320.

[0085] In the above embodiment and modified examples, the imaging range R has a rectangular shape and there are four first imaginary points PA. However, there is no limitation on the shape of the imaging range R. There is also no limitation on the number of first imaginary points PA, as long as it is three or more.

[0086] Furthermore, in the above embodiment, an example has been given in which the same number of laser irradiation sections 142 as the number of first imaginary points PA that define one imaging range R are provided. However, the number of laser irradiation sections 142 is not limited.

[0087] In the above embodiment and modified examples, the index information 230 includes the outer edge information 232 and a plurality of first imaginary points PA. However, the index information 230 does not have to include the outer edge information 232.

[0088] In the above embodiment and modified examples, the case where second camera 132 is a visible light camera has been described as an example. However, second camera 132 may be a near-infrared camera, an infrared camera, an ultraviolet camera, a spectroscopic camera, or a hyperspectral camera.

[0089] In a comparative example in which an image obtained by a near-infrared camera or an infrared camera is subjected to a process for orienting the image, feature points indicating the state of deterioration are buried in the background, resulting in a problem of low accuracy in detecting the state of deterioration. In contrast, the imaging systems 100 and 300 can orient the second camera 132 directly toward the inspection range 20 (inspection surface 12). Therefore, the imaging systems 100 and 300 can inspect the state of deterioration without performing an orienting process on the second image 220. Therefore, when the second camera 132 is a near-infrared camera or an infrared camera, the imaging systems 100 and 300 can detect the state of deterioration of the inspection object 10 with particularly high accuracy compared to the comparative example.

[0090] This disclosure can contribute, for example, to Goal 9 of the Sustainable Development Goals (SDGs), which is to "Build resilient infrastructure, promote sustainable industrialization, and foster innovation." [Explanation of symbols]

[0091] 100 Imaging System 110 moving device (irradiation displacement unit, camera position change unit) 120 Camera 1 132 Second Camera 134 Camera position change mechanism (camera position change unit) 142 Laser irradiation unit 144 Irradiation unit displacement mechanism (irradiation displacement unit) 156 memory 178 Index synthesis section 180 Irradiation position control unit (irradiation displacement unit) 184 Camera position control unit (camera position change unit) 300 Imaging System 320 Holding part 330 Displacement mechanism (imaging position change unit) 382 Position control unit (imaging position change unit)

Claims

1. a first camera that captures an inspection range on an inspection surface of an object to be inspected and generates a first image; an index combining unit that converts index information indicating a plurality of first virtual points that define one or a plurality of imaging ranges, and combines the index information with the first image so that the plurality of first virtual points included in the index information are included within the inspection range on the first image; a laser irradiation unit that irradiates the inspection surface with laser light; an irradiation displacement unit that displaces each of the laser irradiation units so that irradiation points of the laser light from each of the laser irradiation units coincide with a plurality of first virtual points that define one of the imaging ranges on the first image on which the index information is combined; a second camera that captures an image of the inspection range and generates a second image; a camera position changing unit that displaces or rotates the second camera so that a plurality of second virtual points that are set in advance on the second image and that define the imaging range coincide with the respective irradiation points; An imaging system comprising:

2. a first camera that captures an inspection range on an inspection surface of an object to be inspected and generates a first image; an index combining unit that converts index information indicating a plurality of first virtual points that define one or a plurality of imaging ranges, and combines the index information with the first image so that the plurality of first virtual points included in the index information are included within the inspection range on the first image; a laser irradiation unit that irradiates the inspection surface with laser light; a second camera that captures an image of the inspection range and generates a second image; a holding unit that integrally holds the laser irradiation unit and the second camera; an imaging position changing unit that displaces or rotates the holding unit so that, on the first image onto which the index information is combined, irradiation points of the laser light from each of the laser irradiation units coincide with a plurality of first virtual points that define one imaging range, and a plurality of second virtual points that are set in advance on the second image and that define the imaging range coincide with the respective irradiation points; An imaging system comprising:

3. The imaging system according to claim 1 , wherein the second camera is a near-infrared camera or an infrared camera.

4. An imaging method using a first camera that captures an image of an inspection range on an inspection surface of an object to be inspected and generates a first image, a laser irradiation unit that irradiates the inspection surface with laser light, and a second camera that captures an image of the inspection range and generates a second image, a process of converting index information indicating a plurality of first virtual points defining one or a plurality of imaging ranges, the index information being included in the plurality of first virtual points, and compositing the index information with the first image so that the plurality of first virtual points are included in the inspection range on the first image; a process of displacing each of the laser irradiation units so that irradiation points of the laser light from each of the laser irradiation units coincide with a plurality of first virtual points that define one of the imaging ranges on the first image onto which the index information is combined; a process of displacing or rotating the second camera so that a plurality of second virtual points that are set in advance on the second image and that define the imaging range coincide with the respective illumination points; An imaging method comprising:

5. An imaging method using a first camera that captures an image of an inspection range on an inspection surface of an object to be inspected and generates a first image, a laser irradiation unit that irradiates the inspection surface with laser light, a second camera that captures an image of the inspection range and generates a second image, and a holding unit that integrally holds the laser irradiation unit and the second camera, a process of converting index information indicating a plurality of first virtual points defining one or a plurality of imaging ranges, the index information being included in the plurality of first virtual points, and compositing the index information with the first image so that the plurality of first virtual points are included in the inspection range on the first image; a process of displacing or rotating the holding unit so that, on the first image onto which the index information has been combined, irradiation points of the laser light from each of the laser irradiation units coincide with a plurality of first virtual points that define one of the imaging ranges, and a plurality of second virtual points that are set in advance on the second image and that define the imaging range coincide with the respective irradiation points; An imaging method comprising:

Images