Dimensional measurement method

Abstract

To provide a dimension measuring method and dimension measuring device for measuring a dimension by using an imaging device, capable of saving time / effort required for imaging as much as possible.SOLUTION: A dimension measuring method comprises: a target installation step S1 of installing a plurality of targets 3 at measuring object points 23 such that reference points 17 of the multiple targets 3 are located within a prescribed reference plane 21, where each target includes a marker recording surface 15 on which a marker 19 representing the reference point 17 is written; a target imaging step S3 of capturing images of markers 19 of the targets 3 with an imaging device 5; image correction and conversion steps S5 and S7 of correcting and converting each image to remove distortion thereof; and a dimension calculation step S9 of calculating dimensions of positional relations of the respective reference points 17 of the targets 3.SELECTED DRAWING: Figure 9

Description

[Technical field]

[0001] The present invention relates to Dimensional measurement method The present invention relates to a method for measuring dimensions, and more particularly to a method for measuring dimensions using an imaging device. [Background technology]

[0002] Conventionally, the progress of a road (road under construction) 301 has been managed as shown in Fig. 19. The road under construction 301 shown in Fig. 19 is in a state where the surface layer of the asphalt pavement has been peeled off during repair of a paved road. Fig. 19 also shows a cross section of the road under construction 301 taken along a plane perpendicular to the longitudinal direction (Y direction) of the road under construction 301. In the road under construction 301 shown in Fig. 19, a central portion 307, excluding both ends 303 and 305 in the width direction, is rectangular and concave downward.

[0003] In managing the progress of road 301 under construction, a level line 309 is installed extending in the X direction so that dimension L10 in the Z direction is a constant value. A number of scales 311 are used to measure the distance between top surface 313 of central portion 307 and level line 309. This makes it possible to measure the depth of central portion 307 from top surfaces 317 of both ends 303, 305 at a number of points. Note that reference numeral 315 in FIG. 19 denotes a board on which information about road 301 under construction is written. The item shown in FIG. 19 is photographed and kept as a record.

[0004] In recent years, against the backdrop of rapid technological innovation in the information field, such as computers and communication technology, there has been a movement to utilize these information and communication technologies in the construction industry. It is expected that the introduction and spread of a rational construction production system will lead to a transformation from a labor-intensive industry to a knowledge and technology-intensive industry, and thus to a more attractive industry.

[0005] A known relative height calculation device is disclosed in Patent Document 1. The relative height calculation device disclosed in Patent Document 1 is a device that calculates the relative height between a measurement point and a reference surface using an image of a first reference target, an image of a second reference target, an image of a measurement target, and an image of a scale target with known dimensions.

[0006] When calculating the relative height, the coordinates of a representative point of a first reference target placed on a reference surface are calculated from two or more images of the first reference target placed on a reference surface, and the coordinates of a representative point of a second reference target are calculated from two or more images of the second reference target placed on the reference surface.

[0007] In addition, the coordinates of the representative point of the measurement target are calculated from two or more images taken of the measurement target placed at the measurement point, and a reference line passing through the representative point of the first reference target and the representative point of the second reference target is obtained. Furthermore, a surface including the reference line is set as a reference surface, and the relative height between the measurement point and the reference surface is calculated based on the images taken of the scale target, the coordinates of the representative point of the measurement target, and the reference surface. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] JP 2020-84521 A Summary of the Invention [Problem to be solved by the invention]

[0009] However, the conventional relative height calculation device shown in Patent Document 1 calculates relative height using two or more images, which means that it is necessary to take multiple photographs of a target from different directions by moving the shooting location and changing the shooting angle, which results in a problem of a lot of work being required for the photographing process.

[0010] This problem occurs not only in the management of road construction volume, but also when measuring the dimensions of other objects by photographing them with a photographing device.

[0011] The present invention measures dimensions using an imaging device. Dimensional measurement method To provide a camera capable of minimizing the time and effort required for photography. [Means for solving the problem]

[0012] A dimension measurement method according to an embodiment of the present invention includes a target installation step of installing a plurality of targets at a location to be measured, the plurality of targets being formed on a plane and having a marker recording surface on which markers indicating reference points are written, with the reference points of the plurality of targets being located within a predetermined reference plane and the marker recording surfaces of the plurality of targets facing one side; a total photography step of photographing the markers of all of the plurality of targets installed in the target installation step with a photography device; a partial photography step of photographing the markers of some of the markers of all of the plurality of targets installed in the target installation step with a photography device in a state in which a portion of the image obtained in the total photography step is enlarged; and performing correction to remove distortion from a single image obtained in the total photography step, The dimension measurement method includes an overall image correction / conversion step of converting the single image obtained in the overall photographing step into an image obtained by photographing the marker recording surfaces of the multiple targets installed in the target installation step from the front, a partial image correction / conversion step of correcting the single image obtained in the partial photographing step to remove distortion and converting the single image obtained in the partial photographing step into an image obtained by photographing the marker recording surfaces of the multiple targets installed in the target installation step from the front, and a dimension calculation step of calculating the dimensions of the positional relationship of each of the reference points of the multiple targets installed in the target installation step using the image corrected and converted in the overall image correction / conversion step, the image corrected and converted in the partial image correction / conversion step, and dimension values ​​of the markers of the targets.

[0013] In a dimension measurement method according to an aspect of the present invention, the location to be measured in the target installation step is a road under construction having a recessed central portion except for both ends in the width direction, the reference plane in the target installation step is a plane perpendicular to the longitudinal direction of the road under construction, the target installation step is a step of installing one target of the plurality of targets at one end in the width direction of the road under construction, installing another target of the plurality of targets at the other end in the width direction of the road under construction, and installing the remaining targets of the plurality of targets at a central portion in the width direction of the road under construction, and the dimension calculation step is a step of calculating a dimension by comparing a reference point of the target installed at one end in the width direction of the road under construction in the target installation step with a reference point of the target installed at one end in the width direction of the road under construction in the target installation step and a reference point of the target installed at the other end in the width direction of the road under construction. a reference line which is a straight line connecting the reference point of the target installed at the other end of the road under construction in the width direction of the road under construction in the target installation stage, using the image corrected and converted in the entire image correction and transformation stage; calculating a dimension between the reference line and the reference point of the target installed in the center of the road under construction in the target installation stage, using the image corrected and converted in the entire image correction and transformation stage and the dimension values ​​of the marker of the target; determining a depth dimension of the center of the road under construction using this calculated dimension; and calculating a dimension between the reference points of the targets installed in the center of the road under construction in the target installation stage, using the image corrected and converted in the partial image correction and transformation stage and the dimension values ​​of the marker of the target.

[0014] A dimension measurement method according to an aspect of the present invention includes a target installation step of installing a plurality of targets at a measurement location, the plurality of targets being formed on a plane and having a marker recording surface on which markers indicating reference points are written, such that each of the reference points of the plurality of targets is located within a predetermined reference plane and the marker recording surface of the plurality of targets faces one side; an imaging step of photographing all of the markers of the plurality of targets installed in the target installation step by photographing the markers of all of the plurality of targets using an imaging device multiple times so that a portion of all of the markers are captured; and a step of correcting all the images obtained in the photographing step to remove distortion and converting all the images obtained in the target setting step into images obtained by photographing the marker recording surfaces of the multiple targets set in the target setting step from the front; a step of synthesizing the multiple images obtained in the image correction and conversion step to obtain an image in which all the markers are shown; and a step of calculating dimensions of the positional relationship between each of the reference points of the multiple targets set in the target setting step using the image obtained in the image synthesis step and the dimensional values ​​of the markers of the targets.

[0015] Furthermore, a dimension measurement method according to an aspect of the present invention is a dimension measurement method having a position information acquisition step of acquiring position information of the measured point in the target installation step, and a storage step of associating the dimension calculated in the dimension calculation step with the position information acquired in the position information acquisition step and storing them in a memory unit.

[0016] In addition, in a dimension measurement method according to an aspect of the present invention, there are a plurality of measurement locations in the target installation step, the target installation step is a step of installing a plurality of the targets at each of the plurality of measurement locations, the photographing step is a step of photographing markers of the plurality of targets installed at each of the plurality of measurement locations in the target installation step with the photographing device, the image correction / conversion step is a step of correcting each of the plurality of images obtained in the target photographing step to remove distortion and converting each of the plurality of images obtained in the target photographing step into an image photographed from the front, the dimension calculation step is a step of calculating dimensions for each of the plurality of images corrected and converted in the image correction / conversion step, and the storage step is a step of associating each of the plurality of groups of dimensions calculated in the dimension calculation step for each of the plurality of images corrected and converted in the image correction / conversion step with each of the position information acquired in the position information acquisition step in a report format and storing them in the memory unit. Effect of the Invention

[0017] According to the present invention, dimensions are measured using an imaging device. Dimensional measurement method This has the effect of minimizing the effort required for photography. [Brief description of the drawings]

[0018] [Figure 1] 1 is a plan view showing a road under construction, a target installation state, etc. in a dimension measuring method according to an embodiment of the present invention. [Diagram 2] FIG. 1 shows targets of a dimension measurement method (dimension measurement system) according to an embodiment of the present invention, where the left figure in (a) is a front view of the first target, the center figure in (a) is a side view of the first target, the right figure in (a) is a back view of the first target, (b) is a figure showing the second target similar to (a), and (e) is a figure showing the fifth target similar to (a). [Diagram 3]FIG. 2 is a front view showing a state after a target installation step in the dimension measurement method according to the embodiment of the present invention. [Figure 4] 4 is a view taken along the arrow IV in FIG. 3. [Diagram 5] FIG. 5 is a diagram showing a cross section taken along the line VV in FIG. [Figure 6] In a dimension measurement method according to an embodiment of the present invention, (a) is a diagram showing an image obtained in the target shooting stage, (b) is a diagram showing an image corrected in the image correction / conversion stage, and (c) is a diagram showing an image corrected and converted in the image correction / conversion stage. [Figure 7] In a dimension measurement method according to an embodiment of the present invention, (a) is a plan view of a target installed in the target installation stage, (b) is a front view of the target installed in the target installation stage, and (c) is a side view of the target installed in the target installation stage. [Figure 8] 1 is a block diagram showing a schematic configuration of a dimension measuring system according to an embodiment of the present invention. [Figure 9] 1 is a flowchart outlining a dimension measuring method according to an embodiment of the present invention. [Figure 10] FIG. 4 corresponds to FIG. 3 and shows a target photographing stage according to a modified example. [Figure 11] FIG. 4 corresponds to FIG. 3 and shows a target photographing stage according to a modified example. [Figure 12] FIG. 4 corresponds to FIG. 3 and shows a target photographing stage according to a modified example. [Figure 13] 4 is a front view showing a state (a state different from FIG. 3) after a target installation step in the dimension measuring method according to the embodiment of the present invention. FIG. [Figure 14] 4 is a front view showing a state after a target installation step in the dimension measuring method according to the embodiment of the present invention (a state different from FIG. 3). FIG. [Figure 15] 4 is a front view showing a state after a target installation step in the dimension measuring method according to the embodiment of the present invention (a state different from FIG. 3). FIG. [Figure 16]4 is a front view showing a state after a target installation step in the dimension measuring method according to the embodiment of the present invention (a state different from FIG. 3). FIG. [Figure 17] FIG. 2 is a diagram showing a form obtained by the dimension measuring method according to the embodiment of the present invention. [Figure 18] 18 is a diagram showing a form (a form of a different aspect from the form shown in FIG. 17) obtained by the dimension measuring method according to the embodiment of the present invention. FIG. [Figure 19] FIG. 1 is a diagram showing a conventional dimension measuring method. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] A dimension measurement system 1 according to an embodiment of the present invention is used, for example, as a road completion management system. As shown in Figs. 1 to 3 and 8, the dimension measurement system 1 is configured to include a plurality of targets 3 (3A, 3B, 3C, 3D, 3E), an image capture device 5, an image correction unit 7, an image conversion unit 9 (image correction / conversion unit 11), and a dimension calculation unit 13.

[0020] For ease of explanation, the width direction of the road is defined as the X direction, the extension direction of the road is defined as the Y direction, and the direction perpendicular to the road surface is defined as the Z direction. In a case where the road extends horizontally (a flat road), the X and Y directions are horizontal, and the Z direction is vertical.

[0021] The target 3 is configured to include a marker recorded surface 15 formed on a plane. Markers 19 indicating reference points 17 are recorded in a two-dimensional manner on the marker recorded surface 15. For example, one target 3 is provided with one marker recorded surface 15, and one marker 19 is recorded on one marker recorded surface 15. One reference point 17 is provided on one marker 19.

[0022] 2, the target 3 is configured to include a base material 39. The base material 39 is formed by folding a rectangular material at a right angle at a folding line located in the center of the longitudinal direction, so that the base material 39 is "L" shaped in a side view. Because of the "L" shape, the base material 39 is configured to include a rectangular flat bottom portion 41 and a rectangular flat upright portion 43.

[0023] 3 to 5, when the target 3 is placed on the measurement location 23, the thickness direction of the bottom portion 41 is in the Z direction, and the bottom portion 41 is in surface contact with the upper surface of the measurement location 23. When the target 3 is placed on the measurement location 23, the standing portion 43 is in the Y direction, and stands up from the upper surface of the measurement location 23.

[0024] 2, one surface in the thickness direction of the standing portion 43 (the surface opposite the bottom portion 41) is a marker recorded surface 15. Markers 19 are written on the marker recorded surface 15, and the markers 19 indicate reference points 17. A number indicating the number of the target 3 and a symbol indicating the center of the target 3 (for example, a filled triangle) are written on the other surface in the thickness direction of the standing portion 43 (the surface on the bottom portion 41 side).

[0025] The position of the reference point 17 on the target 3 coincides with that of each of the targets 3. For example, the shape of the base material 39 of the target 3A coincides with that of the base material 39 of the other targets 3B, etc. Furthermore, the position of the reference point 17 on the base material 39 of the target 3A coincides with the position of the reference point 17 on the base material 39 of the target 3B, etc. In the embodiment shown in FIG. 2, etc., the reference point 17 is located at the upper left end of the marker 19, but the reference point 17 may be located at another location (for example, the center) of the marker 19.

[0026] The targets 3 (3A to 3E) are placed at the measured location 23 such that each of these reference points 17 is located within a predetermined reference plane 21 (so that each is located as a single point within the reference plane 21). The targets 3 (3A to 3E) are placed at the measured location 23 such that the marker recording surface 15 faces one side and is spaced apart from each other at a predetermined interval. The reference plane 21 is a predetermined plane that is perpendicular to the Y direction (for example, the extension direction of the road).

[0027] For example, a mobile terminal (functional mobile phone such as a smart phone) equipped with a communication function is used as the photographing device 5. The photographing device 5 photographs the markers 19 of the multiple targets 3 (3A to 3E) placed at the measurement location 23.

[0028] The image correction section 7 of the image correction and conversion section 11 is adapted to correct distortion (Seidel aberration such as distortion aberration caused by the lens of the image capture device 5) of one image obtained by image capture with the image capture device 5. The image conversion section 9 of the image correction and conversion section 11 is adapted to convert (for example, projective transformation) one image obtained by image capture with the image capture device 5 into an image obtained by capturing the marker recording surface 15 of the multiple targets 3 (3A to 3E) installed at the measured location 23 from the front. The image obtained by image capture with the image capture device 5 is sent to the image correction and conversion section 11 by a mobile communication system such as 5G. The processing in the image correction and conversion section 11, the dimension calculation section 13, etc. is performed by, for example, cloud computing.

[0029] The image corrected and converted by the image correction and conversion unit 11 is referred to as a corrected and converted image. The dimension calculation unit 13 calculates the dimensions of the positional relationship between each of the reference points 17 of the multiple targets 3 (3A to 3E) that have been placed. This calculation of dimensions is performed using the corrected and converted image and the actual dimension values ​​of the markers 19 of the targets 3.

[0030] The measurement location 23 is a road under construction (road before completion) 31 in which a central portion 29, excluding both ends 25, 27 in the width direction, is concave. Examples of the road under construction 31 include a newly constructed road before paving, which does not have a surface layer of asphalt pavement, or a road in which the surface layer of asphalt pavement has been peeled off during repair of a paved road. In the road under construction 31, the central portion 29, excluding both ends 25, 27 in the width direction, is concave due to the absence of a surface layer of asphalt pavement. In FIG. 3, the central portion 29 is rectangular.

[0031] The reference plane 21 on which the target 3 is placed is a plane perpendicular to the longitudinal direction (extension direction; Y direction) of the road 31 under construction.

[0032] As shown in Fig. 3, one target 3A of the multiple targets 3 (3A to 3E) is set at one end 25 in the width direction of the road under construction 31. Another target 3B of the multiple targets 3 (3A to 3E) is set at the other end 27 in the width direction of the road under construction 31. The remaining targets 3C, 3D, and 3E of the multiple targets 3 (3A to 3E) are set at a central portion 29 in the width direction of the road under construction 31. All of the targets 3 are set in contact with the upper surface (surface) of the road under construction 31 and on top of the upper surface of the road under construction 31.

[0033] A straight line connecting the reference point 17 of the target 3A installed at one end 25 in the width direction of the road 31 under construction and the reference point 17 of the target 3B installed at the other end 27 in the width direction of the road 31 under construction is defined as a reference line 33. The dimension calculation unit 13 is configured to calculate dimensions L1, L2, and L3 between the reference line 33 and the reference points 17 of the targets 3C, 3D, and 3E installed at the center 29 of the road 31 under construction. Then, the calculated dimensions are used to determine the depth dimension (dimension in the Z direction) of the center 29 of the road 31 under construction.

[0034] The calculated depth dimension value of the central portion 29 of the road under construction 31 is stored in the memory unit 37 in the form of a report (see Figs. 17 and 18). The contents of the report format shown in Figs. 17 and 18 are outputted by an output unit such as an LCD.

[0035] 8, the dimension measurement system 1 is configured to include a position information acquisition unit (for example, a position information acquisition unit using GPS) 35 that acquires position information of the measurement location 23 where the target 3 is placed. The dimension calculated by the dimension calculation unit 13 and the position information acquired by the position information acquisition unit 35 are stored in a storage unit 37 in association with each other.

[0036] As shown in Fig. 1, there are a plurality of measurement points 23 (23A, 23B, 23C, 23D). When used in the dimension measurement system 1, a plurality of targets 3 (3A to 3E) are set at each of the plurality of measurement points 23 (23A to 23D). The imaging device 5 is configured to image all of the markers 19 of the plurality of targets 3 (3A to 3E) set at each of the plurality of measurement points 23 (23A to 23D) for each measurement point 23.

[0037] The image correction unit 7 corrects each of the multiple images (for example, four images of the multiple measurement points 23A to 23D) obtained by the imaging device 5 to remove distortion. The image conversion unit 9 converts each of the multiple images corrected by the image correction unit 7 into an image captured from the front. The dimension calculation unit 13 calculates the dimensions of each of the multiple images corrected and converted by the image correction / conversion unit 11.

[0038] In this case, the storage unit 37 stores, in a form format, each of the multiple groups of dimensions calculated by the dimension calculation unit 13 and the position information acquired by the position information acquisition unit 35 for each of the multiple images corrected and converted by the image correction / conversion unit 11 in association with each other. That is, the storage unit 37 stores, in a form format, each of the multiple groups of dimensions for each of the measurement points 23 in association with the position information.

[0039] The location information acquisition unit 35 is provided, for example, in the photographing device 5, and the location information acquired by the location information acquisition unit 35 is incorporated into the Exif information of the image obtained by photographing with the photographing device 5 and is sent to the image correction / conversion unit 11 and the memory unit 37.

[0040] Next, a dimension measuring method according to an embodiment of the present invention will be described. The dimension measuring method according to an embodiment of the present invention is performed, for example, by using the dimension measuring system 1 according to the embodiment of the present invention described above.

[0041] As shown in FIG. 9, the dimension measuring method according to the embodiment of the present invention comprises a target setting step S1, a target photographing step S3, image correction / conversion steps S5 and S7, and a dimension calculation step S9.

[0042] The target setting stage S1 is a stage in which the multiple targets 3 are set such that each of the reference points 17 of the multiple targets 3 is located within a predetermined reference plane 21 (located as one point existing within the reference plane 21). The target setting stage S1 is a stage in which the multiple targets 3 are set at the measurement location 23 such that the marker recording surfaces 15 of the multiple targets 3 face one side (one side in the Y direction).

[0043] Moreover, the target setting stage S1 is a stage in which the multiple targets 3 are set at the measurement location 23 such that the multiple targets 3 are spaced apart from each other at a predetermined interval in the X direction. Furthermore, in the target setting stage S1, each of the multiple targets 3 is set such that the marker recording surface 15 of the multiple targets 3 has a predetermined attitude with respect to the reference plane 21 and faces in one direction (the near side in the Y direction).

[0044] The target photographing stage S3 is a stage in which the markers 19 of all of the targets 3 placed in the target setting stage S1 are photographed by the photographing device 5. For example, photographing is performed only once in the target photographing stage S3. Also, in the target photographing stage S3, as shown in FIG. 3, photographing is performed so that the markers 19 of all of the targets 3 fit into one image.

[0045] Furthermore, in the target photographing stage S3, as shown in Figures 4 and 5, the photographing device 5 is moved in the Y direction away from the target 3 set in the target setting stage S1, and the target 3 is photographed by the photographing device 5.

[0046] The image correction step S5 of the image correction and conversion steps is a step for correcting distortion of one image (only one image) obtained in the target photographing step S3. The distortion is, for example, Seidel aberration such as distortion aberration caused by the lens of the photographing device 5.

[0047] 4 and 5, an image is captured with the image capture device 5 in the position and attitude of P1 as shown in FIG. 4 and FIG. 5, the position and attitude of P1 make the planar image sensor (e.g., a CMOS sensor) 47 of the image capture device 5 parallel to the reference plane 21. In other words, the optical axis 49 of the lens of the image capture device 5 is perpendicular to the reference plane 21.

[0048] The image obtained by photographing with the photographing device 5 in the position and attitude of P1 is distorted as shown in Fig. 6(a). Note that reference numeral 45 in Fig. 6(a) denotes a subject (subject corresponding to the marker 19) formed in a square shape. By performing the correction in the image correction stage S5, the image shown in Fig. 6(a) becomes an image as shown in Fig. 6(c).

[0049] 4 and 5, an image is captured with the image capturing device 5 in the position and attitude of P2. Due to the position and attitude of P2, the planar image sensor 47 of the image capturing device 5 and the reference plane 21 are not parallel to each other. In other words, the optical axis 49 of the lens of the image capturing device 5 is tilted with respect to the reference plane 21.

[0050] The image conversion stage S7 of the image correction and conversion stages is a stage for converting (for example, projective transformation) one image obtained in the target photographing stage S3 (the image corrected in the image correction stage S5). That is, the image conversion stage S7 is a stage for converting one image obtained in the target photographing stage S3 into an image obtained by photographing the marker recording surfaces 15 of the multiple targets 3 from the front.

[0051] To explain further, if there is no distortion in the image obtained by photographing with the photographing device 5 in the position and attitude of P2 as shown in Figures 4 and 5, the subject 45 will have a shape other than a square, such as a trapezoid, as shown in Figure 6(b). By the conversion in the image conversion stage S7, the image shown in Figure 6(b) becomes the image shown in Figure 6(c).

[0052] Through image correction and conversion steps S5 and S7, the image obtained in target photographing step S3 becomes a corrected and converted image. As described above, the corrected and converted image is an image photographed in a state in which the optical axis 49 of the lens of the photographing device 5 is perpendicular to the reference plane 21. The corrected and converted image is an image obtained when the marker recording surface 15 of the target 3 is photographed from an infinite distance using a super telephoto lens.

[0053] In the above description, the conversion in the image conversion step S7 is performed after the correction in the image correction step S5, but the correction in the image correction step S5 may be performed after the conversion in the image conversion step S7. Also, the correction in the image correction step S5 may be performed inside the photographing device 5.

[0054] The dimension calculation step S9 is a step for calculating the dimensions of the relative positional relationship between each of the reference points 17 of the multiple targets 3 installed in the target installation step S1. The dimension calculation is performed using the corrected and converted image, which is a single image corrected and converted in the image correction and conversion steps S5 and S7, and the known dimension values ​​of the markers 19 of the targets 3.

[0055] The dimensional values ​​of the marker 19 do not refer to the dimensional values ​​of the marker 19 itself as they appear in the corrected / converted image, but to the dimensional values ​​of the actual marker 19. Also, instead of using the dimensional values ​​of the marker 19, the dimensional values ​​of another part of the target 3 may be used. Also, the dimensional values ​​of a scale other than the target 3 (a scale that is transferred together with the target 3 by the imaging device 5 and represents a certain dimension as it appears in the corrected / converted image) may be used.

[0056] Here, the setting of the target 3 in the target setting stage S1 will be described in more detail.

[0057] Naturally, the target 3 (marker recording surface 15) can translate with three degrees of freedom in three-dimensional space and can rotate with three degrees of freedom. That is, the target 3 in three-dimensional space can move (translate) in the X, Y, and Z directions without changing its posture, and can rotate (change its posture) around the A axis extending in the X direction, the B axis extending in the Y direction, and the C axis extending in the Z direction.

[0058] In the target installation step S1, the marker recording surface 15 of the target 3 is installed so that the reference point 17 is located within the reference plane 21, and is in a predetermined attitude with respect to the reference plane 21.

[0059] In a first embodiment, the marker recorded surface 15, which is in a predetermined position relative to the reference plane 21, is located within the reference plane 21. That is, in the first embodiment, the marker recorded surface 15 is part of the reference plane 21. In a second embodiment, the marker recorded surface 15, which is in a predetermined position relative to the reference plane 21, rotates around the C axis and is tilted with respect to the reference plane 21.

[0060] In the first embodiment, the target 3 is placed in the P3 position shown in Fig. 7(a), whereas in the second embodiment, the target 3 is placed in the P4 position shown in Fig. 7(a) (a position slightly rotated around the C axis from the P3 position).

[0061] Incidentally, it is considered unlikely that the target 3 will be installed in the position shown by P5 in Fig. 7(b) (a position rotated around the B axis from the position of P3). This is because, in order for the target 3 to assume the position shown by P5, it would be necessary for the target 3 to sink into the road 31 under construction, which is normally unthinkable. For the same reason, it is considered unlikely that the target 3 will be installed in the position shown by P6 in Fig. 7(c) (a position rotated around the A axis from the position of P3).

[0062] In the target setting stage S1, the target 3 is set, for example, in the first mode described above. That is, in the target setting stage S1, the marker recording surface 15 of each of the multiple targets 3 is positioned within the reference plane 21, and each of the multiple targets 3 is set.

[0063] In the first aspect above, where the marker recorded surface 15 is located within the reference plane 21, the direction of the normal vector of the reference plane 21 and the direction of the normal vector of the marker recorded surface 15 coincide with each other. In addition, in the aspect where the marker recorded surface 15 is located within the reference plane 21, in the direction of the normal vector, the position of the marker recorded surface 15 and the position of the reference plane 21 coincide with each other.

[0064] The case where the marker recording surface 15 (marker 19) is placed in the first mode will be described in more detail with reference to FIG.

[0065] An example will be described in which five targets 3 (first target 3A, second target 3B, third target 3C, fourth target 3D, and fifth target 3E) are set in the target setting stage S1. The first target 3A and second target 3B are set as reference targets, and the third target 3C, fourth target 3D, and fifth target 3E are set as non-reference targets.

[0066] In the target setting stage S1, the first target 3A to the fifth target 3E are set so that each of the marker recording surfaces 15 is positioned within the reference plane 21, as described above.

[0067] In dimension calculation step S9 using the corrected and transformed image, the reference point 17 of the marker 19 of the first target 3A is set as the origin 53. A straight line passing through the reference point 17 of the marker 19 of the first target 3A and the reference point 17 of the marker 19 of the second target 3B is set as the first reference line 33. A straight line perpendicular to the first reference line 33 and passing through the reference point 17 of the marker 19 of the first target 3 is set as the second reference line 51.

[0068] In the dimension calculation step S9 using the corrected and transformed image, the actual dimension L5 (L5A, L5B) of the marker 19 of the first target 3A is set as the scale reference. Then, the coordinates of the reference point 17 of the marker 19 of the second target 3B are calculated based on the origin 53, the first reference line 33, and the second reference line 51. In addition, the coordinates of the reference point 17 of the marker 19 of the third target 3C, the coordinates of the reference point 17 of the marker 19 of the fourth target 3D, and the coordinates of the reference point 17 of the marker 19 of the fifth target 3E are calculated.

[0069] That is, in the dimension calculation step S9 using the corrected / transformed image, the distance from the origin 53 in the extension direction (X direction) of the first reference line 33 of each of the reference points 17 of the markers 19 of the second to fifth targets 3 is calculated. Also, the distance from the origin 53 in the extension direction (Z direction) of the second reference line 51 of each of the reference points 17 of the markers 19 of the second to fifth targets 3 is calculated.

[0070] An example will be given for further explanation. In the corrected and converted image, the external shape of the marker 19 of the first target 3A is assumed to be a square. Also, the value (dimension value) of the length L5 (L5A, L5B) of one side of the square of the marker of the first target 3A is assumed to be 150 mm in the actual product.

[0071] In the corrected and converted image, the value of the length of one side of the square of marker 19 of first target 3A is 10 (dimensionless number). The value of the distance from origin 53 in the X direction of reference point 17 of marker 19 of third target 3C is 120 (dimensionless number). In this case, the value of distance L6 from origin 53 in the X direction of reference point 17 of marker 19 of third target 3C is 1800 mm (= 150 mm × 120 ÷ 10).

[0072] Also, the value of the distance from origin 53 in the Z direction to reference point 17 of marker 19 of third target 3C is assumed to be 35 (dimensionless number). In this case, the value of distance L1 from origin 53 in the Z direction to reference point 17 of marker 19 of third target 3C is 525 mm (= 150 mm × 35 ÷ 10).

[0073] Next, the case where the marker recording surface 15 (target 3) is placed in the second mode will be described in more detail.

[0074] In the second embodiment, in the target installation step S1, each of the first target 3A to the fifth target 3E is installed tilted and rotated around the C axis with respect to the reference plane 21. Even in this case, each of the reference points 17 of the markers 19 of the first to fifth targets 3 is located within the reference plane 21.

[0075] That is, each of the marker recording surfaces 15 of the markers 19 of the first to fifth targets 3 is rotated and tilted at an individual angle around the C axis with respect to the reference plane 21 (see target 3 (P4) in FIG. 7(a)). Since the planar bottom portion 41 is in surface contact with the planar upper surface of the measurement point 23, a situation may occur in which the target 3 is rotated around the C axis and placed at an angle in the target placement stage S1.

[0076] In the dimension calculation step S9 using the corrected and transformed image in the second mode, the coordinates of each of the reference points 17 of the markers 19 of each target 3 are calculated in the same manner as when the marker recording surface 15 is placed in the first mode. However, when the marker recording surface 15 is placed in the second mode, the dimension L5B in the Z direction of the first marker is used as the scale reference in the dimension calculation step S9 using the corrected and transformed image. This is because the value of the dimension L5A is projected as smaller than the value of the dimension L5B due to the target 3A rotating around the C axis.

[0077] In the above description, in the target setting step S1, the reference points 17 of all the targets 3 are positioned within the reference plane 21. Here, the reference points 17 of the reference targets 3A and 3B may be positioned within the reference plane 21, and the reference points 17 of the non-reference targets 3C, 3D, and 3E may be shifted from the reference plane 21 in the Y direction relative to the reference plane 21. In this case, in the corrected and transformed image, the sizes of the non-reference targets 3C, 3D, and 3E will differ from the sizes of the reference targets 3A and 3B. However, this difference in size may be used to calculate the dimensions in the dimension calculation step S9.

[0078] Moreover, in a dimension measurement method (road as-built management method for pavement repair work and the like) according to an embodiment of the present invention, the measured location 23 in the target installation stage S1 is a predetermined location on the road 31 under construction. In the road 31 under construction, a central portion 29 excluding both ends 25, 27 in the width direction is recessed. When viewed in the Y direction, the central portion 29 has a rectangular shape that is long in the X direction. Moreover, the reference plane 21 in the target installation stage S1 is a plane perpendicular to the longitudinal direction (extension direction) of the road 31 under construction.

[0079] In the target setting stage S1, one target 3A of the multiple targets 3 is set at one end 25 in the width direction of the road under construction 31, and another target 3B of the multiple targets 3 is set at the other end 27 in the width direction of the road under construction 31. Also, in the target setting stage S1, the remaining (one or more) targets 3 (3C, 3D, 3E) of the multiple targets 3 are set at the center 29 in the width direction of the road under construction 31.

[0080] When there are multiple targets 3 to be installed in the center 29 of the width of the road under construction 31, these multiple targets 3 (3C, 3D, 3E) are installed at a predetermined interval in the width direction (X direction) of the road under construction 31, as shown in Figure 3 etc.

[0081] A straight line connecting reference point 17 of target 3A installed at one end in the width direction of road 31 under construction and reference point 17 of target 3B installed at the other end 27 in the width direction of road 31 under construction is defined as the first reference line 33. Targets 3A and 3B were installed in target installation stage S1. The first reference line 33 extends in the width direction (X direction) of road 31 under construction.

[0082] In the dimension calculation stage S9, the dimensions (dimensions in the vertical Z direction) between the first reference line 33 and each of the reference points 17 of the multiple targets 3C, 3D, and 3E installed in the central part 29 of the road 31 under construction in the target installation stage S1 are calculated.

[0083] In the dimension calculation step S9, the calculated dimensions L1, L2, and L3 are used to find the depth dimension of the center portion 29 of the road 31 under construction.

[0084] The dimension calculation step S9 calculates the vertical dimensions L1, L2, L3 of a group for each of the multiple targets 3C, 3D, 3E placed in the central portion 29. As described above, if the reference points 17 of the targets 3 are placed at the same positions for each of the multiple targets 3, the calculated vertical dimensions become the depth dimensions L1, L2, L3 of the group in the central portion 29.

[0085] In addition, in the dimension calculation stage S9, in the same manner as when determining the vertical dimension, the dimension (X-direction dimension) of the reference point 17 of the target 3 installed in the widthwise center 29 of the road 31 under construction from the reference point 17 of the target 3A is also calculated.

[0086] Moreover, the dimension measurement method according to the embodiment of the present invention includes a position information acquisition step of acquiring position information of the measurement point 23 in the target installation step S1. Moreover, the dimension measurement method according to the embodiment of the present invention stores in the memory unit 37 the group of dimensions L1, L2, L3 calculated in the dimension calculation step S9 and the position information acquired in the position information acquisition step in association with each other.

[0087] In the dimension measurement method according to the embodiment of the present invention, there are a plurality of measurement points 23 (23A, 23B, 23C, 23D) in the target setting stage S1 as shown in Fig. 1. In the target setting stage S1, a plurality of targets 3 are set at each of the plurality of measurement points 23.

[0088] In the target photographing step S3, the markers 19 of the multiple targets 3 that were placed at the multiple measurement points 23 in the target placement step S1 are photographed by the imaging device 5.

[0089] In the image correction and conversion stages S5 and S7, each of the multiple images obtained in the target photographing stage S3 is corrected to remove distortion, and each of the multiple images obtained in the target photographing stage S3 is converted into an image photographed from the front.

[0090] In the dimension calculation step S9, the dimensions of the (relative) positional relationships of each of the reference points 17 of the multiple targets 3 are calculated for each of the multiple images corrected and converted in the image correction and conversion steps S5 and S7.

[0091] In the storage step, each of the groups of dimensions calculated in the dimension calculation step S9 is associated with the position information acquired in the position information acquisition step and is stored in the storage unit 37 in the form of a form.

[0092] The dimension measurement method according to the embodiment of the present invention includes a target installation step S1 in which a target 3 is installed at a measurement location 23, and a target photographing step S3 in which a marker 19 of the installed target 3 is photographed. The dimension measurement method also includes image correction and conversion steps S5 and S7 in which one image obtained in the target photographing step S3 is corrected and converted. Furthermore, a dimension calculation step S9 of the dimension measurement method is adapted to calculate the dimensions of the positional relationship between each of the reference points 17 of the multiple targets 3, using the corrected and converted image corrected and converted in the image correction and conversion steps S5 and S7, and the dimensional values ​​of the markers 19 of the target 3.

[0093] This eliminates the need to photograph the target 3 multiple times with the imaging device 5 from different directions by moving the imaging location and changing the imaging angle, and only one imaging session is required. This also makes it possible to minimize the effort (man-hours) required for imaging when measuring dimensions using the imaging device 5.

[0094] Moreover, in the dimension measuring method according to the embodiment of the present invention, the multiple targets 3 are each placed so that the marker recording surface 15 of the multiple targets 3 is located within the reference plane 21. This allows the dimension to be measured with the imaging device 5 with the error minimized.

[0095] In the dimension measurement method according to the embodiment of the present invention, the location to be measured 23 in the target installation stage S1 is a road under construction 31 with a recessed central portion 29. In the target installation stage S1, one target 3A is installed at one end 25 of the road under construction 31, and another target 3B is installed at the other end 27 of the road under construction 31. In the target installation stage S1, the remaining targets 3C, 3D, and 3E are installed in the central portion 29 of the road under construction 31.

[0096] Furthermore, in the dimension measuring method according to the embodiment of the present invention, a straight line connecting the reference point 17 of the target 3A placed at one end 25 in the width direction of the road under construction 31 and the reference point 17 of the target 3B placed at the other end 27 in the width direction is set as the reference line 33. In the dimension calculation stage S9, the dimension between the reference line 33 and the reference points 17 of the targets 3C, 3D, and 3E placed in the central portion 29 of the road under construction 31 is calculated. Then, the calculated dimension is used to obtain the depth dimension of the central portion 29 of the road under construction 31.

[0097] This makes it possible to manage the progress of road construction while minimizing the effort (man-hours) required to photograph the target 3.

[0098] In addition, in the dimension measurement method according to the embodiment of the present invention, the dimension calculated in the dimension calculation step S9 and the location information acquired in the location information acquisition step are associated with each other and stored in the storage unit 37. This makes it possible to easily identify the location where the progress management of the road 31 under construction was carried out.

[0099] Furthermore, in the dimension measurement method according to the embodiment of the present invention, each of the multiple groups of dimensions calculated in the dimension calculation stage S9 is associated with the position information acquired in the position information acquisition stage and stored in the storage unit 37 in the form of a form. This allows accurate management of the progress at multiple measured locations (measured locations lined up at predetermined intervals in the Y direction) of the road 31 under construction. Note that the dimension measurement system 1 can also achieve the same effects as the dimension measurement method.

[0100] In the above-described dimension measuring method, the photographing of the multiple targets 3 by the photographing device 5 may be carried out multiple times. A dimension measuring method according to this modified example will be described.

[0101] The dimension measuring method according to the modified example comprises a target setting step, an overall photographing step, a partial photographing step, an overall image correcting and converting step, a partial image correcting and converting step, and a dimension calculating step.

[0102] As described above, the target installation step is a step of installing the multiple targets 3 at the measurement points 23. This installation is performed so that each of the reference points 17 of the multiple targets 3 is located within a predetermined reference plane 21 and the marker recording surfaces 15 of the multiple targets 3 face one side.

[0103] The whole photographing stage (whole photographing stage), as shown in FIG. 10, is a stage in which the markers 19 of all of the targets 3 placed in the target placement stage are photographed by the photographing device 5.

[0104] That is, in the overall photographing stage, the targets 3A, 3B, 3C, 3D, and 3E are photographed using the photographing device 5, and an image in which the targets 3A, 3B, 3C, 3D, and 3E are photographed is obtained. More specifically, in the overall photographing stage, the subject within a rectangular area indicated by reference numeral 55 is photographed. The photographing in FIG. 10 is performed from an angle (20° to 30°) slightly above the upper surface 57 of the road. The photographing in the overall photographing stage is performed, for example, only once.

[0105] The dimension L11 shown in Fig. 10 is, for example, about 3 m, the dimension L12 shown in Fig. 10 is, for example, about 1.5 m, and the dimension L13 shown in Fig. 10 is also, for example, about 1.5 m. The dimension L14 shown in Fig. 10 is, for example, about 30 cm. In other words, when multiple targets 3 are installed at the target installation stage, the separation distance between the targets 3 in the X direction is orders of magnitude larger than the separation distance between the targets 3 in the Z direction (about 10 times larger).

[0106] 11, the partial photographing stage is a stage in which the markers 19 of some of the targets 3 among all the markers 19 of the targets 3 installed in the target installation stage are photographed by the photographing device 5. In the partial photographing stage, the markers 19 of the targets 3 are photographed in a state in which a part of the image obtained in the whole photographing stage is enlarged.

[0107] That is, in the partial photographing stage, an image capturing targets 3A, 3C, and 3D is obtained using the photographing device 5. More specifically, in the partial photographing stage, a subject within a rectangular area indicated by reference numeral 59 is photographed. The photographing in FIG. 11 is also taken from an angle (20° to 30°) slightly above the upper surface 57 of the road. The photographing in the partial photographing stage shown in FIG. 11 is taken, for example, only once.

[0108] In addition, as shown in Figure 12, the partial photographing stage is configured to photograph the markers 19 of a portion of the multiple targets 3 among all the markers 19 of the targets 3 installed in the target installation stage using the photographing device 5.

[0109] That is, in the partial shooting stage shown in Fig. 12, an image capturing targets 3B, 3D, and 3E is obtained using the shooting device 5. More specifically, in the partial shooting stage, a subject within a rectangular area indicated by reference numeral 61 is captured. The shooting in Fig. 12 is also performed from an angle (20° to 30°) slightly above the upper surface 57 of the road. The shooting in the partial shooting stage shown in Fig. 12 is performed, for example, only once.

[0110] As already understood, the partial photographing stage is photographed multiple times, for example, with different objects being photographed. All targets 3 are photographed by these multiple partial photographing stages. The targets 3 and road under construction 31 shown in Figures 11 and 12 have not been altered in any way and are the same as the targets 3 and road under construction 31 shown in Figure 10.

[0111] The overall image correction and conversion stage is a stage for correcting one image (overall captured image) obtained in the overall photographing stage to remove distortion. The overall image correction and conversion stage is also a stage for converting one image (overall captured image; image of rectangular area 55 in FIG. 10) obtained in the overall photographing stage into an image obtained by photographing the marker recording surface 15 of the multiple targets 3 installed in the target installation stage from the front. The correction and conversion in the overall image correction and conversion stage is performed in the same manner as in the image correction and conversion stages S5 and S7 described above.

[0112] The partial image correction and conversion stage is a stage for correcting one image (partially captured image) obtained in the partial shooting stage to remove distortion. The partial image correction and conversion stage is also a stage for converting one image (partially captured image) obtained in the partial shooting stage into an image obtained by photographing the marker recording surface 15 of the multiple targets 3 installed in the target installation stage from the front. The partial image correction and conversion stage is performed in the same manner as the image correction and conversion stages S5 and S7 described above.

[0113] In the partial image correction / conversion stage, correction and conversion are performed for each of the images obtained by multiple shooting (the image in FIG. 11, the image in FIG. 12). The partial shooting stage, etc. are performed in order to calculate with higher accuracy the dimensions of the positional relationship between each of the reference points 17 of the multiple targets 3 installed in the target installation stage. The image in FIG. 11 is the image of the rectangular area 59 in FIG. 11. The image in FIG. 12 is the image of the rectangular area 61 in FIG. 12.

[0114] The dimension calculation stage is a stage in which the dimensions of the positional relationship of each of the reference points 17 are calculated using the image corrected and converted in the overall image correction and conversion stage, the image corrected and converted in the partial image correction and conversion stage, and the dimension values ​​of the target markers. The dimensions of the positional relationship of each of the reference points 17 are the dimensions of the positional relationship of each of the reference points 17 of the multiple targets 3 installed in the target installation stage. The dimension calculation stage is performed in the same manner as the dimension calculation stage S9 described above.

[0115] As described above, the location to be measured in the target installation stage is a road under construction 31, which is recessed in the central portion 29 except for both ends 25, 27 in the width direction, as shown in Fig. 3. The reference plane 21 in the target installation stage is a plane perpendicular to the longitudinal direction of the road under construction 31.

[0116] The target installation stage is a stage in which one target 3A of the multiple targets 3 is installed at one end in the width direction of the road under construction 31, and another target 3B of the multiple targets is installed at the other end in the width direction of the road under construction 31. The target installation stage is also a stage in which the remaining targets 3C, 3D, and 3E of the multiple targets 3 are installed in the center 29 in the width direction of the road under construction 31.

[0117] In the dimension calculation stage, a reference line 33 which is a straight line connecting the reference point 17 of the target 3A and the reference point 17 of the target 3B is obtained using the image corrected and converted in the overall image correction and conversion stage.

[0118] In the dimension calculation stage, the Z-direction dimensions between the reference line 33 and the reference points 17 of the targets 3C, 3D, and 3E are calculated using the image corrected and converted in the overall image correction / conversion stage and the dimension values ​​of the markers 19 of the target 3. In the dimension calculation stage, the depth dimension of the center 29 of the road under construction 31 is obtained using the above calculated dimensions.

[0119] In the dimension calculation stage, the dimension in the X direction between the reference points 17 of the targets 3C, 3D, and 3E is calculated using the image corrected and converted in the partial image correction / conversion stage and the dimension value of the marker 19 of the target 3. The dimension in the X direction between the reference points 17 of the targets 3C, 3D, and 3E is indicated by reference characters L12 and L13 in FIG.

[0120] In the dimension measurement method according to the modified example, an image corrected and converted in the overall image correction and conversion stage, an image corrected and converted in the partial image correction and conversion stage, and the dimension value of the marker 19 of the target 3 are used. Then, the positional relationship of each of the reference points 17 of the multiple targets 3 is obtained. This makes it possible to calculate the dimension of the positional relationship of each of the reference points 17 of the multiple targets 3 with less error.

[0121] In the dimension measuring method according to the modified example, the reference line 33 is obtained using the image corrected and converted in the overall image correction and conversion stage. Also, in the dimension measuring method according to the modified example, the Z direction dimension between the reference line 33 and the reference points 17 of the targets 3C, 3D, and 3E is calculated using the image corrected and converted in the overall image correction and conversion stage and the dimension value of the target marker 19. This makes it possible to easily obtain the reference line 33, and also to easily obtain the Z direction dimension between the reference line 33 and the reference points 17 of the targets 3C, 3D, and 3E, which is a relatively small value.

[0122] In the dimension measurement method according to the modified example, the dimension in the X direction between the reference points 17 of the targets 3C, 3D, and 3E installed in the center of the road under construction 31 is calculated using the image partially corrected and converted in the image correction / conversion stage and the dimension value of the target marker 19. This makes it possible to find the relatively large dimension in the X direction between the reference points of the targets installed in the center of the road under construction 31 with as little error as possible.

[0123] Next, the measurement of dimensions of a road 31 under construction will be described with reference to Figs. 13 to 16. Fig. 13 shows a road that has been used for many years, with an old base layer 65 provided on a roadbed 67, and an old surface layer 63 provided on the old base layer 65. The height dimensions of the reference line 33 (the dimension between the reference line 33 and the top surface of the surface layer 63) at each of the locations where the targets 3A, 3B, and 3C are installed are represented by reference characters HA1, HA2, and HA3.

[0124] The values ​​of the height dimensions HA1 and HA3 can be obtained using the image corrected and converted in the image correction and conversion stage and the dimensional value of the marker 19 of the target 3. The dimension value HA2 can be obtained using the image corrected and converted in the image correction and conversion stage and the dimensional value of the marker 19 of the target 3, and the dimension UA2 in the Z direction between the reference line 33 and the reference point of the target 3B. Note that in Figure 13, the value of the dimension UA2 is drawn as "0".

[0125] In FIG. 14, the base layer 65 and the surface layer 63 on the roadbed 67 are removed from the one shown in FIG. 13. The height dimensions of the reference line 33 (the dimension between the reference line 33 and the upper surface of the roadbed 67) at the locations where the targets 3C, 3D, and 3E are installed are represented by reference characters HB1, HB2, and HB3. In addition, the targets 3A and 3C are close to each other in the X direction, and the targets 3B and 3E are close to each other. As a result, there is only a slight difference between the value of the dimension in the Z direction between the upper surface of the roadbed 67 and the reference point 17 of the target 3A and the value of the dimension in the Z direction between the upper surface of the roadbed 67 and the reference point 17 of the target 3C, which is practically acceptable.

[0126] The cutting thicknesses TB1, TB2, and TB3 at the locations where the targets 3C, 3D, and 3E are placed are expressed as the difference between the dimensions HA1, HA2, and HA3 shown in FIG. 13 and the dimensions HB1, HB2, and HB3 shown in FIG. 14. That is, they are obtained as TB1=HB1-HA1, TB2=HB2-HA2, and TB3=HB3-HA3. Furthermore, TB1=UB1, TB2=UB2, and TB3=UB3. UB1, UB2, and UB3 are the dimensions in the Z direction between the reference line 33 and the reference points 17 of the targets 3C, 3D, and 3E. Moreover, the line segment 69 shown in FIG. 14 indicates the upper surface of the surface layer 63 shown in FIG. 13.

[0127] In Fig. 15, a new base layer (a base layer constituting an asphalt pavement) 65 is provided on the surface shown in Fig. 14. The height dimensions of the reference line 33 (the dimension between the reference line 33 and the upper surface of the base layer 65) at the locations where the targets 3C, 3D, and 3E are installed are represented by reference characters HC1, HC2, and HC3.

[0128] The thicknesses TC1, TC2, and TC3 of the base layer 65 at the locations where the targets 3C, 3D, and 3E are placed are expressed as the differences between the dimensions HB1, HB2, and HB3 shown in Fig. 14 and the dimensions HC1, HC2, and HC3 shown in Fig. 15. Furthermore, they are expressed as TC1=UB1-UC1, TC2=UB2-UC2, and TC3=UB3-UC3. UC1, UC2, and UC3 are the dimensions in the Z direction between the reference line 33 and the reference points 17 of the targets 3C, 3D, and 3E. The line segment 69 shown in Fig. 15 also indicates the upper surface of the surface layer 63 shown in Fig. 13.

[0129] In Fig. 16, a new surface layer (surface layer constituting an asphalt pavement) 63 is provided on the surface shown in Fig. 15. The height dimensions (dimension between the reference line 33 and the upper surface of the base layer 65) of the reference line 33 at each of the locations where the targets 3C, 3D, and 3E are installed are represented by reference characters HD1, HD2, and HD3. The thicknesses TD1, TD2, and TD3 of the surface layer 63 at each of the locations where the targets 3A, 3B, and 3C are installed are represented by the difference between the dimensions HC1, HC2, and HC3 shown in Fig. 15 and the dimensions HD1, HD2, and HD3 shown in Fig. 16. The dimensions HD1, HD2, and HD3 shown in Fig. 16 can be obtained in the same way as the height dimensions HA1 and HA3 shown in Fig. 13.

[0130] In the dimension measurement methods shown in Figures 15 and 16, the measured location in the target installation stage is a road under construction, the reference plane in the target installation stage is a plane perpendicular to the longitudinal direction of the road under construction, the target installation stage comprises a first target installation stage and a second target installation stage, the target photographing stage comprises a first target photographing stage and a second target photographing stage, the image correction and conversion stage comprises a first image correction and conversion stage and a second image correction and conversion stage, and the dimension calculation stage comprises a first dimension calculation stage and a first dimension calculation stage.

[0131] In addition, in the dimension measurement method shown in Figures 15 and 16, the first target installation step is a step of installing one of the multiple targets at one end of the road under construction in the width direction, installing another of the multiple targets at the other end of the road under construction in the width direction, and installing the remaining targets of the multiple targets in a central portion that is recessed compared to both ends of the road under construction in the width direction.

[0132] In addition, in the dimension measurement method shown in Figures 15 and 16, the first target photographing step is a step of photographing the markers of the multiple targets installed in the first target installation step with an imaging device, and the first image correction / conversion step is a step of correcting the single image obtained in the first target photographing step to remove distortion, and converting the single image obtained in the first target photographing step into an image obtained by photographing the marker recording surfaces of the multiple targets installed in the first target installation step from the front.

[0133] In addition, in the dimension measurement method shown in Figures 15 and 16, the first dimension calculation stage uses the image corrected and converted in the first image correction and conversion stage and the dimension values ​​of the target marker, sets a straight line connecting the reference point of the target installed at one end of the width of the road under construction in the first target installation stage and the reference point of the target installed at the other end of the width of the road under construction in the first target installation stage as a reference line, calculates the dimension between this reference line and the reference point of the target installed in the center of the road under construction in the first target installation stage, and uses this calculated dimension to find the depth dimension of the center of the road under construction.

[0134] In addition, in the dimension measurement method shown in Figures 15 and 16, the second target installation stage is a stage in which one target installed at one end of the width of the road under construction in the first target installation stage and one target installed at the other end of the width of the road under construction are left as they are, and the remaining targets of the multiple targets are installed on a newly installed layer in the center of the width of the road under construction (above the base layer or surface layer; approximately in the same place in the X direction as the targets installed in the first target installation stage).

[0135] In addition, in the dimension measurement method shown in Figures 15 and 16, the second target photographing stage is a stage in which one target installed at one end of the road under construction in the width direction, one target installed at the other end of the road under construction in the width direction, and the markers of the multiple targets installed in the second target installation stage are photographed by an imaging device.

[0136] In addition, in the dimension measurement method shown in Figures 15 and 16, the second image correction / conversion stage corrects the single image obtained in the second target photographing stage to remove distortion, and also converts the single image obtained in the second target photographing stage into an image obtained by photographing the marker recording surfaces of the multiple targets installed in the second target installation stage from the front.

[0137] In addition, in the dimension measurement method shown in Figures 15 and 16, the second dimension calculation stage uses the reference line, the image corrected and converted in the second image correction and conversion stage, and the dimension values ​​of the target marker to calculate the dimension between the reference line and the reference point of the target installed in the center of the road under construction in the second target installation stage, uses this calculated dimension to determine the depth dimension of the center of the road under construction, and uses this depth dimension and the depth dimension of the center of the road under construction determined in the first dimension calculation stage to determine the thickness dimension of a newly installed layer (base layer or surface layer) in the center of the width of the road under construction.

[0138] Here, a dimension measuring method according to another modified example will be described.

[0139] A dimension measuring method according to another modified example is configured to include the above-mentioned target setting step, photographing step, image correction / conversion step, image synthesis step, and dimension calculation step.

[0140] The photographing stage is a stage in which the markers 19 of all of the targets 3 installed in the target installation stage are photographed multiple times using the photographing device 5 so that a portion of all of these markers 19 are captured in the photograph. This is the stage in which all of the markers 19 are photographed.

[0141] The image correction and conversion stage is a stage in which correction is performed to remove distortion from each of all images obtained in the photographing stage. Also, the image correction and conversion stage is a stage in which each of all images obtained in the photographing stage is converted into an image obtained by photographing the marker recording surface 15 of each of the multiple targets 3 installed in the target installation stage from the front.

[0142] The image synthesis stage is a stage in which the multiple images obtained in the image correction and conversion stage are synthesized to obtain a single image in which all of the markers 19 are captured.

[0143] The dimension calculation stage is a stage in which the dimensions of the positional relationship between each of the reference points 17 of the multiple targets 3 installed in the target installation stage are calculated using the images obtained in the image synthesis stage and the dimensional values ​​of the markers 19 of the targets 3.

[0144] In the above explanation, the image is considered as a still image, but a moving image (a moving image in which all targets 3 are captured by changing the shooting direction) may be used as the image, and an image similar to the image obtained in the image synthesis stage may be obtained from this moving image. Also, when shooting a moving image, the zoom function of the lens may be used.

[0145] Although the present embodiment has been described above, the present embodiment is not limited to this, and various modifications are possible within the scope of the gist of the present embodiment. [Explanation of symbols]

[0146] 1 Dimensional measurement system 3, 3A, 3B, 3C, 3D, 3E targets 5. Imaging Equipment 11 Image correction and conversion section 13 Dimension calculation section 15 Marker recording surface 17 Reference points 19 Marker 21 Reference plane 23, 23A, 23B, 23C, 23D Measured location 25, 27 End 29 Central part 31 Road under construction 33 Reference Line 35 Location information acquisition section 37 Memory section S1 Target placement stage S3 Target shooting stage S5, S7 Image correction and conversion stages S9 Dimension calculation stage

Claims

1. a target setting step of setting a plurality of targets at measurement locations such that each of the targets has a marker recording surface formed on a plane and has a marker indicating a reference point written thereon, the reference points of the targets being located within a predetermined reference plane and the marker recording surfaces of the targets facing one side; a whole image capturing step of capturing images of all the markers of the plurality of targets that have been placed in the target placement step by an image capturing device; a partial photographing step of photographing a part of the markers of all the targets installed in the target installation step by a photographing device in a state in which a part of the image obtained in the whole photographing step is enlarged; a whole image correction and conversion step of correcting the single image obtained in the whole image capturing step to remove distortion, and converting the single image obtained in the whole image capturing step into an image obtained by capturing the marker recording surfaces of the multiple targets installed in the target installation step from the front; a partial image correction and conversion step of correcting the one image obtained in the partial photographing step to remove distortion, and converting the one image obtained in the partial photographing step into an image obtained by photographing the marker recording surfaces of the multiple targets installed in the target installation step from the front; a dimension calculation step of calculating dimensions of positional relationships of each of the reference points of the plurality of targets installed in the target installation step, using the image corrected and converted in the whole image correction and conversion step, the image corrected and converted in the partial image correction and conversion step, and the dimensional values ​​of the markers of the targets; having The measurement location in the target installation stage is a road under construction in which the center portion except for both ends in the width direction is recessed, The reference plane in the target installation stage is a plane perpendicular to the longitudinal direction of the road under construction, the target installation step is a step of installing one target of the plurality of targets at one end of the road under construction in the width direction, installing another target of the plurality of targets at the other end of the road under construction in the width direction, and installing the remaining targets of the plurality of targets in a center of the road under construction in the width direction; The dimension calculation step is a step of determining a reference line, which is a straight line connecting a reference point of a target installed at one end of the width direction of the road under construction in the target installation step and a reference point of a target installed at the other end of the width direction of the road under construction in the target installation step, using the image corrected and converted in the entire image correction / conversion step, calculating the dimension between the reference line and the reference point of a target installed in the center of the road under construction in the target installation step, using the image corrected and converted in the entire image correction / conversion step and the dimension value of the marker of the target, determining a depth dimension of the center of the road under construction using this calculated dimension, and calculating the dimension between the reference points of targets installed in the center of the road under construction in the target installation step, using the image corrected and converted in the partial image correction / conversion step and the dimension value of the marker of the target.

2. a position information acquiring step of acquiring position information of a measurement point in the target setting step; a storage step of storing the dimensions calculated in the dimension calculation step and the position information acquired in the position information acquisition step in a storage unit in association with each other; The method for measuring dimensions according to claim 1, further comprising:

3. There are a plurality of measurement points in the target placement step, and the target placement step is a step of placing a plurality of targets at each of the plurality of measurement points, The photographing step is a step of photographing the markers of the plurality of targets, which are respectively installed at the plurality of measurement points in the target installation step, by the photographing device; The image correction and conversion step is a step of correcting each of the plurality of images obtained in the target photographing step to remove distortion, and converting each of the plurality of images obtained in the target photographing step into an image photographed from the front, The size calculation step is a step of calculating the size of each of the plurality of images corrected and converted in the image correction and conversion step, The dimension measurement method according to claim 2, wherein the storage step is a step of associating each of the multiple groups of dimensions calculated in the dimension calculation step for each of the multiple images corrected and converted in the image correction / conversion step with each of the positional information acquired in the positional information acquisition step in a report format in the memory unit.

Images