Inclination measurement system, inclination measurement method, and inclination measurement jig

Abstract

To provide an inclination measurement system, an inclination measurement method, and an inclination measurement jig that can measure the inclination of a structure accurately and relatively easily.SOLUTION: The system is a measurement system 1A that measures the inclination of a steel column 6 and includes at least two or more inclination measurement jigs 40 attached to different locations on the steel column 6, a data acquisition unit capable of acquiring point cloud data 2 of the inclination measurement jigs 40, and an inclination measurement unit that measures the inclination of the steel column 6 based on the point cloud data 22 of the inclination measurement jigs 40 acquired by the data acquisition unit.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a tilt measurement system, a tilt measurement method, and a tilt measurement jig. [Background technology]

[0002] Conventionally, techniques for measuring the tilt of a structure have been known, such as that described in Patent Document 1.

[0003] Patent Document 1 describes a method for inspecting the erection of a steel-framed structure. In the inspection method described in Patent Document 1, a jig equipped with a measuring ruler is attached to two locations, one above and one below, of the structure, and a measurer looks into a transit and reads the scale on the ruler of the jig to measure the deviation in the verticality of the structure.

[0004] However, in the inspection method described in Patent Document 1, the inspector visually performs the inspection, so if the jig is attached at a relatively high position, it is difficult to read the scale on the ruler, and it is expected that it will be difficult to accurately measure the tilt of the structure. From the perspective of improving measurement accuracy, an inspection method can also be adopted in which a jig with a prism is attached to the structure, light irradiated from a measuring device is reflected by the prism, and the position of the jig is automatically measured by measuring the reflected light. However, the jig with a prism is relatively heavy and difficult to handle. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 5-133748 Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention has been made in consideration of the above-mentioned circumstances, and the problem it aims to solve is to provide a tilt measurement system, a tilt measurement method, and a tilt measurement jig that can measure the tilt of a structure accurately and relatively easily. [Means for solving the problem]

[0007] The problem to be solved by the present invention is as described above, and the means for solving this problem will now be described.

[0008] That is, claim 1 provides a tilt measurement system for measuring the tilt of a structure, comprising at least two tilt measurement jigs that are attached to different locations on the structure, a data acquisition unit capable of acquiring point cloud data of the tilt measurement jigs, and a tilt measurement unit that measures the tilt of the structure based on the point cloud data of the tilt measurement jigs acquired by the data acquisition unit.

[0009] In claim 2, the invention further comprises a flyable unmanned aerial vehicle, and the data acquisition unit acquires point cloud data of the tilt measurement jig using the unmanned aerial vehicle.

[0010] Claim 3 provides a tilt measurement method for measuring the tilt of a structure, comprising an attachment process for attaching at least two or more tilt measurement jigs to different locations on the structure, a data acquisition process for acquiring point cloud data of the tilt measurement jigs using a data acquisition unit, and a measurement process for measuring the tilt of the structure based on the point cloud data of the tilt measurement jigs acquired by the data acquisition unit.

[0011] In claim 4, the data acquisition unit acquires point cloud data of the tilt measurement jig using a flyable unmanned aerial vehicle.

[0012] Claim 5 provides a tilt measurement jig for measuring the tilt of a structure, comprising: an attachment part that can be attached to any location on the structure; and a determination part that is connected to the attachment part and has a mark that can determine a reference position using point cloud data acquired by a specified data acquisition part.

[0013] In claim 6, the defining portion is rotatably connected to the mounting portion, and is configured so that the orientation of the mark can be changed to any direction.

[0014] In claim 7, the defining portion is connected to the mounting portion so as to be rotatable in a predetermined direction, and the defining portion has the mark on both sides in the predetermined direction.

[0015] In claim 8, the structure is a steel pillar, and the attachment portion is configured to be detachable from the steel pillar by using a magnetic force.

[0016] In claim 9, the mounting portion has two mounting surfaces formed in an approximately L-shape when viewed in a plane, and each mounting surface is attached to two horizontally adjacent side surfaces of the steel column. [Effects of the Invention]

[0017] The present invention has the following effects.

[0018] In the present invention, the tilt of a structure can be measured accurately and relatively easily. [Brief explanation of the drawings]

[0019] [Figure 1] 1A is a schematic diagram showing a measurement system according to a first embodiment of the present invention, and FIG. 1B is a plan view showing a marker. [Figure 2] FIG. 1 is a block diagram showing a measurement system according to a first embodiment. [Figure 3] FIG. 10 is an explanatory diagram showing a hue circle for explaining the relationship between the hues of the regions of the mark. [Figure 4] 3 is a flowchart showing each step of a measurement method using the measurement system according to the first embodiment. [Figure 5] (a) Plan view showing an example of markers installed on foundations. (b) Plan view showing an example of markers installed on piles. [Figure 6] 1A is a schematic diagram showing point cloud data of the marker according to the present embodiment, and FIG. 1B is a schematic diagram showing point cloud data of a conventional marker. [Figure 7] 1A is an explanatory diagram showing a first modified example of the marker, FIG. 1B is an explanatory diagram showing a second modified example of the marker, and FIG. 1C is an explanatory diagram showing a third modified example of the marker. [Figure 8] FIG. 1A is a schematic diagram showing a measurement system according to a second embodiment of the present invention. [Figure 9] FIG. 10 is a block diagram showing a measurement system according to a second embodiment. [Figure 10] FIG. [Figure 11] 10 is a flowchart showing each step of a measurement method performed by a measurement system according to a second embodiment. [Figure 12] 10 is a schematic diagram showing an example in which the angle of the marker portion 42 relative to the attachment portion is changed. [Figure 13] 10A is a perspective view showing a tilt measurement jig according to a modified example, and FIG. 10B is a schematic view showing an inspection using the tilt measurement jig according to the modified example. DETAILED DESCRIPTION OF THE INVENTION

[0020] A measurement system 1 according to a first embodiment of the present invention will be described below with reference to FIGS.

[0021] The measurement system 1 shown in Figures 1 and 2 generates point cloud data 2 that constitutes the surface of a measurement object, and performs measurement using the point cloud data 2. Here, "point cloud data 2" refers to a collection of information (point information) that includes three-dimensional coordinate information of one point corresponding to the surface of the measurement object. Each point in the point cloud data 2 also includes color information (e.g., RGB values) that corresponds to the surface of the measurement object. The measurement system 1 can use the point cloud data 2 to measure the dimensions of the measurement object and inspect the measurement object (e.g., inspect the tilt).

[0022] The measurement target may be a structure such as a building (for example, a reinforced concrete frame, a steel frame, etc.). Figures 1(a) and 5(a) show an example in which a foundation 3 (foundation beam) of a reinforced concrete structure is used as an example of a structure to be measured.

[0023] A measurement system 1 according to this embodiment uses SfM (Structure from Motion) technology to generate point cloud data 2 from imaging results (image data) acquired by an unmanned aerial vehicle 10 (described later). The measurement system 1 includes an unmanned aerial vehicle 10, a control device 20, and a marker 30.

[0024] The unmanned aerial vehicle 10 shown in Figures 1(a) and 2 is a small aircraft without a person on board, also known as a drone or UAV. The unmanned aerial vehicle 10 is equipped with multiple rotors (rotating wings) and is capable of stable flight. The unmanned aerial vehicle 10 is equipped with an appropriate GPS receiver and altitude sensor. The unmanned aerial vehicle 10 can fly to a predetermined position based on information from an appropriate operating means, information obtained from the GPS receiver and altitude sensor, and information obtained from a control device 20 described below. The unmanned aerial vehicle 10 is also equipped with a camera 11.

[0025] The camera 11 is capable of capturing an image of the measurement target. The camera 11 captures the image through a predetermined lens unit and acquires the captured image as image data. In this embodiment, the camera 11 is provided so that it can capture images below. As shown in FIG. 1(a), the unmanned aerial vehicle 10 captures images using the camera 11 while flying above the measurement target.

[0026] 2 is capable of processing various types of information. The control device 20 includes a control unit 21, a storage unit 22, a communication unit 23, a display unit 24, and an input unit 25.

[0027] The control unit 21 executes the programs stored in the storage unit 22. The control unit 21 is configured by, for example, a CPU.

[0028] The storage unit 22 stores various information necessary for measurement using the point cloud data 2, such as various programs and drawing data of the structure to be measured. The storage unit 22 is composed of an HDD, RAM, ROM, etc.

[0029] The communication unit 23 transmits and receives information to and from the unmanned aerial vehicle 10. The control device 20 uses the communication unit 23 to acquire image data captured by the camera 11 of the unmanned aerial vehicle 10.

[0030] The display unit 24 displays various types of information and is configured with a liquid crystal display or the like.

[0031] The input unit 25 is used to input various types of information and is configured with a keyboard, a mouse, and the like.

[0032] A general personal computer or the like can be used as the control device 20. Note that the control device 20 is not limited to a personal computer or the like, and an information terminal such as a tablet or a smartphone, an external server, or the like can also be used.

[0033] 1 and 2 is installed on a measurement target and serves as a landmark (anti-aircraft mark) for measurement using point cloud data 2. The installation mode of the marker 30 will be described in detail later. The marker 30 includes a base 31 and a mark 32.

[0034] The base 31 is the main structure of the marker 30. The base 31 is formed in a generally plate shape with the plate surface facing up and down. As shown in FIG. 1(b), the base 31 is formed in a generally square shape when viewed from above. The base 31 is formed of a material that has low reflection of sunlight, such as resin. The base 31 is installed relative to the measurement object. The base 31 is placed on the top surface of the measurement object. It is also possible to install the base 31 relative to the measurement object via a member such as a tripod.

[0035] The mark 32 shown in FIG. 1(b) is capable of defining a reference position in the point cloud data 2. The mark 32 is formed on the upper surface of the base 31. Here, the "reference position" is a position (point) that serves as a reference for measurement using the point cloud data 2. In this embodiment, of the image data of the mark 32, an image of a center point P of the mark 32 in a planar view is identified by the control device 20 as the reference position in the point cloud data 2. The manner in which the reference position of the mark 32 is identified will be described later.

[0036] The mark 32 is divided into four regions of different colors (hues). Each region is formed into a substantially square shape of the same size and shape by a cross-shaped boundary line that passes through the center point P and bisects each side of the mark 32. In other words, the center point P is located at the intersection of the cross-shaped boundary lines. In the illustrated example, the boundary lines are shown with two-dot chain lines. Note that the boundary lines are imaginary lines that indicate the boundaries of each region (each color), and no lines (frame lines) are actually drawn on the boundaries of each region. Also, in the illustrated example, for convenience of explanation, a dot is shown indicating the center point P, but in reality, no dots are drawn at the intersections of the boundary lines.

[0037] In the following description, the regions will be referred to as a first region 32a, a second region 32b, a third region 32c, and a fourth region 32d, respectively. The first region 32a and the second region 32b are not adjacent to each other via a boundary line, but are positioned opposite each other across a center point P. The first region 32a and the second region 32b have an opposite apex angle formed by the cross-shaped boundary line. The hues of the first region 32a and the second region 32b are in a "complementary hue" relationship or a "hue similar to a complementary hue" relationship.

[0038] The relationship between each hue will be explained below using the hue wheel in Figure 3. The numbers 0 to 12 on the hue wheel indicate the hue difference from the hue at the starting point (the vertex in the example). The greater the hue difference, the stronger the color contrast. In the following explanation, a hue wheel consisting of 24 colors will be used.

[0039] Here, a "complementary hue" refers to a hue located directly opposite on the color wheel (having a hue difference of 12 from the starting hue). In this embodiment, "hues similar to a complementary hue" include adjacent complementary hues and hues adjacent to an adjacent complementary hue. An "adjacent complementary hue" refers to a hue located next to a complementary hue on the color wheel (having a hue difference of 11 from the starting hue on the color wheel of FIG. 3). Furthermore, a "hue adjacent to an adjacent complementary hue" refers to a hue located next to the adjacent complementary hue on the color wheel (having a hue difference of 10 from the starting hue on the color wheel of FIG. 3). That is, in this embodiment, the hue difference between the first region 32a and the second region 32b is set to a range from 10 to 12 on the color wheel of FIG. 3. In the following description, the relationship between complementary hues or hues similar to complementary hues (relationships in the range from 10 to 12 on the color wheel in FIG. 3) will be referred to as "approximately complementary color relationships."

[0040] In the above example, the relationship between hues was explained using a color wheel consisting of 24 colors, but it is also possible to explain the relationship between hues using other color wheels, such as a color wheel consisting of 20 colors. Even when a color wheel consisting of 20 colors is used, the relationship between complementary hues or hues similar to complementary hues (adjacent complementary hues or hues adjacent to adjacent complementary hues) is referred to as an "approximate complementary color relationship."

[0041] The third region 32c and the fourth region 32d shown in FIG. 1(b) are not adjacent to each other across a boundary line but are positioned opposite each other across a center point P, and are adjacent to the first region 32a and the second region 32b, respectively, across the boundary line. The third region 32c and the fourth region 32d have an opposite apex angle formed by the cross-shaped boundary line. The hues of the third region 32c and the fourth region 32d are generally complementary to each other. Note that the third region 32c and the fourth region 32d and the first region 32a and the second region 32b are set to colors that are not generally complementary to each other.

[0042] In this embodiment, the color of each of the above regions is set to a color different from that of other objects captured in the image data. Specifically, the color of each region is set to a color different from that of the concrete, reinforcing bars, and steel frames that make up the structure. This improves the visibility of the center point data 2a in the point cloud data generation step S103, which will be described later.

[0043] The above describes the configuration of the measurement system 1. Next, a measurement method using point cloud data 2 by the measurement system 1 will be described using the flowchart in Fig. 4. As shown in Fig. 4, the measurement method according to this embodiment includes an installation step S101, an image data acquisition step S102, a point cloud data generation step S103, and a measurement step S104.

[0044] The installation step S101 is a step of installing markers 30 on the measurement target. Fig. 1(a) and Fig. 5(a) show an example in which a plurality of markers 30 are installed on the upper surface of the foundation 3. The markers 30 are arranged at predetermined intervals so that the plurality of markers 30 are captured within the imaging range of image data acquired in the image data acquisition step S102, which will be described later.

[0045] In the example shown in FIG. 5(a), markers 30 are placed at positions corresponding to the corners of the foundation 3 in a planar view. The markers 30 are placed so that the corners of the foundation 3 and the center point P of the mark 32 overlap in a planar view. In addition to the corners, in the illustrated example, markers 30 are also placed in the middle of the foundation 3 in the left-right direction. The markers 30 in the middle are placed in pairs with a gap in the width direction (front-to-back direction) of the middle part of the foundation 3. The markers 30 in the middle are placed so that both ends of the middle part of the foundation 3 in the width direction and the center point P of the mark 32 overlap in a planar view.

[0046] The marker 30 is installed by, for example, a worker. The worker also uses an appropriate GPS (GNSS) receiver or the like to measure the position (latitude, longitude, and height) of the center point P of the marker 30 installed on the foundation 3. Information on the position of the center point P is input to the control device 20 using, for example, the input unit 25.

[0047] The image data acquisition process S102 is a process of capturing an image of the foundation 3 using the camera 11 of the unmanned aerial vehicle 10 and acquiring the image data. The unmanned aerial vehicle 10 captures an image of the foundation 3 using the camera 11 while moving above the foundation 3. The unmanned aerial vehicle 10 captures images so as to acquire multiple image data whose imaging ranges partially overlap each other. The image data includes images of the foundation 3 and the markers 30. The image data is transmitted to the control device 20.

[0048] The image data is preferably corrected for lens distortion of the camera 11. The image data is also preferably subjected to image processing to reduce the effects of direct sunlight and shadows on the marker 30 and to make the color of each area as close as possible to a predetermined color code (RGB value). The correction and image processing can be performed by the functions of the camera 11 and the processing of the control device 20.

[0049] The point cloud data generation step S103 is a step of generating point cloud data 2 based on the multiple image data acquired in the image data acquisition step S102. In this embodiment, the control device 20 performs SfM processing to generate point cloud data 2 based on the image data. At this time, the images of the markers 30 included in the image data are also converted into a point cloud.

[0050] The control device 20 can automatically identify center point data 2a, which is a point corresponding to the center point P of the mark 32, from the generated point cloud data 2. Below, the manner in which the center point data 2a is identified will be described with reference to FIG. 6. Note that FIG. 6(a) shows the marker 30 according to this embodiment, and FIG. 6(b) shows a conventional marker 5 used as a general anti-aircraft marker. Each figure shows a schematic enlarged view of the point cloud data 2 around the center point P of each marker (the area surrounded by a dashed line).

[0051] The conventional marker 5 shown in FIG. 6(b) is formed in a checkerboard pattern in which first regions 5a (e.g., black) and second regions 5b (e.g., white or yellow) of different colors are alternately arranged. When the image of the marker 5 is converted into a point cloud, the point information at the boundary between the first region 5a and the second region 5b, which includes point information (pixel) corresponding to the center point P, is displayed in a color obtained by combining the colors (two colors) of the first region 5a and the second region 5b. For this reason, the distinction between the point information corresponding to the center point P and other point information becomes unclear, and it may be difficult to accurately identify the point information of the center point P.

[0052] On the other hand, in the marker 30 according to this embodiment shown in FIG. 6(a), the four regions of the mark 32 (first region 32a, second region 32b, third region 32c, and fourth region 32d) are made to have different colors. Therefore, in the marker 30, the colors combined at the boundary portions of each region are also different. Furthermore, in the marker 30, the center point data 2a, which is point information about the center point P, is displayed as a color obtained by combining the colors (four colors) of each of the above regions, and therefore the color of the center point data 2a is different from any of the colors at the boundary portions of each region. Therefore, the distinguishability (visibility) of the center point data 2a can be improved.

[0053] Furthermore, in the marker 30 according to this embodiment, the hues of regions that are not adjacent across a boundary line are set to be approximately complementary. It is known that mixing complementary colors results in a gray color. In this embodiment, the color of the center point data 2a is a color close to gray as a result of combining the colors of two pairs of regions that are approximately complementary. In the marker 30 according to this embodiment, the regions adjacent to each other across a boundary line are not in a complementary color relationship (approximately complementary color relationship). Therefore, the boundary between the regions is unlikely to be a color close to gray. Only the color of the center point data 2a, where the colors of regions that are not adjacent across a boundary line are combined, is a color close to gray. The control device 20 can identify point information whose color is closest to gray as the center point data 2a. This can further improve the identifiability (visibility) of the center point data 2a. Depending on the density of the point cloud data 2 (the resolution of the image data and the SfM processing settings), multiple gray point information may appear near the center of the marker 30. In this case, the control device 20 analyzes the color code of each piece of point information and can identify the point information with the color code closest to the gray color code (for example, R:127, G127, B127) as the center point data 2a.

[0054] In this embodiment, as described above, it is possible to identify the center point data 2a of the point cloud data 2. The control device 20 can improve the accuracy of the point cloud data 2 by using the identification result of the center point data 2a and information on the position of the center point P of the marker 30 acquired in the installation step S101.

[0055] The measurement step S104 is a step of measuring the measurement target (foundation 3) based on the point cloud data 2 generated in the point cloud data generation step S103. In this embodiment, an example of measuring the shape (each dimension) of the foundation 3 after construction will be described with reference to FIG. 5(a). Specifically, the control device 20 can measure the width dimension of the foundation 3 by measuring the distance between two points of center point data 2a of two markers 5 in the point cloud data 2. In this way, performing measurements using the point cloud data 2 can improve the efficiency of the measurement work. The control device 20 can display the measurement results on the display unit 24. In this embodiment, the accuracy of identifying the center point data 2a of the point cloud data 2 is improved, thereby improving the accuracy of the measurement.

[0056] The above describes an example of a measurement method using the measurement system 1. Note that the measurement method using the measurement system 1 is not limited to the above example, and steps may be added or the content of the steps may be changed as appropriate.

[0057] For example, in the above example, a foundation 3 is used as the measurement target, but the measurement target is not limited to the above example, and various structures can be used as the measurement target. FIG. 5(b) shows an example in which a pile 4 (pile foundation) is used as the measurement target and the measurement system 1 is used to inspect the construction position of the pile 4. In this case, in the installation step S101, the marker 30 is placed so that the center of the pile 4 and the center point P of the mark 32 overlap in a planar view. In this case, the marker 30 is placed at a position corresponding to an appropriate benchmark (reference point for inspection), and in the measurement step S104, the distance between the center of the pile 4 and the benchmark can be measured using the point cloud data 2. With the above configuration, the center of the pile 4, which was previously difficult to identify in the point cloud data 2, can be accurately identified.

[0058] Furthermore, the form of the mark 32 of the marker 30 is not limited to the example described in Fig. 1(b) and can be modified as appropriate. Below, each modified example (first to third modified examples) of the marker 30 will be described with reference to Fig. 7.

[0059] 7(a), the marker 30A according to the first modification is configured such that the hues of adjacent regions (first region 32a and second region 32b, and third region 32c and fourth region 32d) across a boundary line are set to complementary hues or hues similar to complementary hues, rather than regions facing each other across the center point P. With this configuration, although the color of the boundary portions of adjacent regions in the point cloud data 2 is close to the color of the center point data 2a (gray obtained by combining four colors), the color of the center point data 2a can be made different from the color of the boundary portions of each region, thereby improving the distinguishability of the center point data 2a.

[0060] A marker 30B according to a second modification shown in FIG. 7(b) is divided into regions (first region 32a, second region 32b, third region 32c, and fourth region 32d) by boundaries forming diagonal lines of the mark 32. In the above example, each region is formed in a substantially triangular shape. In the marker 30B, the hues of regions that are not adjacent to each other across a boundary line but face each other across the center point P are set to complementary hues or hues similar to complementary hues. The above configuration also achieves substantially the same effects as the marker 30.

[0061] A marker 30C according to a third modification shown in FIG. 7(c) has eight regions (first region 32a, second region 32b, third region 32c, fourth region 32d, fifth region 32e, sixth region 32f, seventh region 32g, and eighth region 32h). In the above example, the regions are divided by the cross-shaped boundary of the marker 30 and the diagonal boundary of the marker 30B. In the marker 30C, the hues of the regions that are not adjacent to each other across the center point P but are opposite each other via a boundary are set to complementary hues or hues similar to complementary hues. The above configuration also achieves substantially the same effects as the marker 30.

[0062] In addition to the above-mentioned examples, the number of regions of the markers 30 to 30C can be any even number equal to or greater than four (for example, six). The number of regions can also be an odd number (for example, five). In this case, the marker includes a pair of regions that are generally complementary in color to each other, as well as at least one region that does not form part of the pair of regions. Furthermore, the above-mentioned markers 30 to 30C have been shown as examples in which the outer shape is substantially square, but are not limited to the above-mentioned example, and various shapes can be used as the outer shape of the markers 30 to 30C.

[0063] The measurement system 1 according to the first embodiment has been described above. Below, a measurement system 1A according to a second embodiment will be described using Fig. 8 to Fig. 13. Note that below, differences from the first embodiment will be described, and descriptions of common configurations will be omitted as appropriate.

[0064] A measurement system 1A according to the second embodiment generates point cloud data 2 using an inclination measurement jig 40, and measures the inclination of a measurement target, which is a structure such as a building, using the point cloud data 2. As shown in FIG. 8, this embodiment shows an example in which a steel frame column 6 is used as the measurement target. Note that FIG. 8 shows the steel frame column 6 in a schematic manner. The steel frame column 6 can be, for example, a steel pipe column or an H-shaped steel.

[0065] Measurement system 1A includes unmanned aerial vehicle 10, control device 20, and tilt measurement jig 40. Note that the configurations of unmanned aerial vehicle 10 and control device 20 are generally similar to those in the first embodiment, and therefore description thereof will be omitted.

[0066] The inclination measurement jigs 40 shown in Figs. 8 to 10 are used to measure the inclination of a steel column 6 relative to the vertical direction. A plurality of inclination measurement jigs 40 are provided at different height positions for one steel column 6. In the example shown in Fig. 8, two inclination measurement jigs 40 are arranged above and below the steel column 6 with a gap between them. The upper and lower inclination measurement jigs 40 have the same configuration. The inclination measurement jig 40 includes an attachment portion 41, a marker portion 42, and an angle adjustment portion 43.

[0067] The mounting portion 41 shown in Figs. 8 and 10 is a portion that can be attached to any location on the steel column 6. The mounting portion 41 is formed in a generally L-shape in a plan view. The mounting portion 41 is formed from resin. This allows for weight reduction and reduces reflection of sunlight. As shown in Fig. 10, the mounting portion 41 has a generally plate-shaped first portion 41a with its plate surface facing left and right, and a generally plate-shaped second portion 41b with its plate surface facing front and rear.

[0068] The first portion 41a is formed in a substantially rectangular shape when viewed in the left-right direction. A mark 32 substantially similar to the mark 32 of the marker 30 according to the first embodiment is formed on the surface (right surface) of the first portion 41a.

[0069] The second portion 41b is formed to extend leftward from the front end of the first portion 41a. The second portion 41b is formed in substantially the same manner as the first portion 41a except for its orientation. Therefore, a description of the configuration of the second portion 41b will be omitted.

[0070] 8, the first part 41a and the second part 41b are attached to two horizontally adjacent side surfaces (the right surface and the front surface) of the steel column 6. In this embodiment, an appropriate magnet is provided on the attachment surface of the first part 41a and the second part 41b to the steel column 6 (the surface opposite to the mark 32). In this way, the attachment part 41 is configured to be detachable from the steel column 6 using magnetic force.

[0071] 10 is connected to the attachment portion 41 and is a portion capable of defining a reference position using point cloud data 2. The marker portion 42 has a configuration generally similar to that of the marker 30 according to the first embodiment. That is, the marker portion 42 has a base portion 42a having a generally plate shape similar to that of the base portion 31, and the mark 32 is formed on the base portion 42a. In this embodiment, two marker portions 42 are provided for the first portion 41a and the second portion 41b, respectively.

[0072] The following description focuses on the marker unit 42 provided on the first portion 41a and describes the marker unit 42. The marker unit 42 is connected to the lower end of the first portion 41a via an angle adjustment unit 43, which will be described later. In the example shown in FIG. 10, the plate surface of the marker unit 42 is oriented diagonally upward and downward. In the marker unit 42 according to this embodiment, the marks 32 are formed on both surfaces of the base 42a: a front surface (a surface facing diagonally upward in FIG. 10) that is vertically adjacent to the surface on which the marks 32 of the first portion 41a are formed, and a back surface (a surface facing diagonally downward in FIG. 10) that is formed on the opposite side of the front surface.

[0073] The angle adjustment portion 43 is a portion that can adjust the angle of the marker portion 42 relative to the mounting portion 41. The angle adjustment portion 43 rotatably connects the marker portion 42 to each of the first portion 41a and the second portion 41b of the mounting portion 41. The angle adjustment portion 43 can be formed by an appropriate hinge. In the example shown in the figure, an example is shown in which two angle adjustment portions 43 are provided for one marker portion 42.

[0074] The angle adjustment unit 43 is configured to change the orientation of each marker unit 42 in any direction and to maintain the attitude of each marker unit 42 after the change. More specifically, the angle of the marker unit 42 provided on the first portion 41a around a rotation axis whose axis is oriented in the front-to-rear direction can be changed to any angle by the angle adjustment unit 43. Furthermore, the angle of the marker unit 42 provided on the second portion 41b around a rotation axis whose axis is oriented in the left-to-right direction can be changed to any angle by the angle adjustment unit 43. The angles of the marks 32 on the upper and lower tilt measurement jigs 40 are set to be approximately the same. In the example shown in FIG. 8, the front surfaces of the marks 32 on each tilt measurement jig 40 are tilted so that they face diagonally upward (diagonally upward at approximately 45° with respect to the horizontal plane).

[0075] The configuration of the measurement system 1A has been described above. Next, a measurement method using point cloud data 2 by the measurement system 1A will be described using the flowchart in Fig. 11. As shown in Fig. 11, the measurement method according to this embodiment includes an installation step S201, an image data acquisition step S202, a point cloud data generation step S203, and a measurement step S204.

[0076] The installation step S201 is a step of attaching the inclination measurement jig 40 to the steel column 6. In the installation step S201, a worker attaches multiple (two in this embodiment) inclination measurement jigs 40 to one steel column 6 at different locations. More specifically, as shown in FIG. 8 , the inclination measurement jigs 40 are attached at different heights on a common face (the right face and the front face) of the steel column 6. Each inclination measurement jig 40 is attached so that a corner (inside corner) formed by the attachment portion 41 roughly coincides with a corner (outside corner) formed by the right face and the front face of the steel column 6. As described above, the inclination measurement jig 40 according to this embodiment has an attachment portion 41 that is formed in a substantially L-shape in plan view, which makes it easier to position the jig relative to the structure (steel column 6).

[0077] The image data acquisition step S202 is a step of capturing an image of the tilt measurement jig 40 using the camera 11 of the unmanned aerial vehicle 10 and acquiring the image data. In this embodiment, the imaging direction of the camera 11 of the unmanned aerial vehicle 10 is set in a direction directly facing the mark 32 on the marker portion 42 of the tilt measurement jig 40 (diagonally downward at approximately 45° from the horizontal). As shown in FIG. 8, the unmanned aerial vehicle 10 flies at a higher position than the tilt measurement jig 40 and captures an image of the marker portion 42 of the tilt measurement jig 40 from diagonally above. At this time, the unmanned aerial vehicle 10 captures the image so as to acquire multiple image data whose imaging ranges partially overlap each other. The image data is transmitted to the control device 20.

[0078] In the image data acquisition process S202, image data capable of generating point cloud data 2 of only the tilt measurement jig 40 may be acquired, or image data capable of generating point cloud data 2 of the entire building structure may be acquired.

[0079] The point cloud data generation step S203 is a step of generating point cloud data 2 based on the multiple image data acquired in the image data acquisition step S202. In the point cloud data generation step S203, the control device 20 performs SfM processing to generate point cloud data 2 of the tilt measurement jig 40, generally similar to the point cloud data generation step S103 of the first embodiment. At this time, the control device 20 can identify center point data 2a, which is a point corresponding to the center point P of the mark 32, from the generated point cloud data 2 (see FIG. 6).

[0080] The measurement step S204 is a step of measuring the inclination of the steel column 6 relative to the vertical direction based on the point cloud data 2 of the inclination measuring jig 40 generated in the point cloud data generation step S203. The control device 20 can measure the inclination of the steel column 6 relative to the vertical direction by comparing the coordinates (horizontal coordinates) of each center point data 2a in the point cloud data 2 of the upper and lower inclination measuring jigs 40.

[0081] The above describes an example of a measurement method using the measurement system 1A. This measurement method allows for accurate and relatively easy measurement of the inclination of a structure (steel column 6). In other words, in conventional measurement methods using surveying equipment such as a transit, a jig with a measuring ruler or a jig with a prism is attached to the structure. However, in methods using a jig with a measuring ruler, the measurer visually inspects the structure. Therefore, if the jig is attached at a relatively high position, it becomes difficult to read the ruler's scale, making it difficult to accurately measure the structure's inclination. Furthermore, in the above method, measuring the same structure multiple times in different directions is burdensome for the measurer. In methods using a jig with a prism, the jig with a prism is relatively heavy and can be difficult to handle. In contrast, the measurement method using the measurement system 1A allows for accurate and relatively easy measurement of the inclination of a structure (steel column 6) by measuring the inclination of the steel column 6 relative to the vertical direction based on the point cloud data 2.

[0082] Furthermore, in this embodiment, the tilt measurement jig 40, which is generally L-shaped in plan view, is provided at a corner of the steel column 6, thereby improving the visibility of the marker portion 42. That is, if a plate-shaped marker such as marker 30 were provided on one side surface (for example, the right surface) of the steel column 6, the marker would be blocked by a beam connected to the side surface, making it difficult to capture an image with the unmanned aerial vehicle 10. On the other hand, if the tilt measurement jig 40, which is generally L-shaped in plan view, is provided at a corner of the steel column 6 as in this embodiment, the marker portion 42 can be positioned near the corner of the steel column 6, and the marker portion 42 can be prevented from being blocked by a beam.

[0083] In addition, in this embodiment, by providing a marker portion 42 on each of the first part 41a and the second part 41b of the mounting portion 41, it is possible to capture images of the marker portion 42 using the unmanned aerial vehicle 10 from either the front-to-back direction or the left-to-right direction.

[0084] Note that the measurement method of the measurement system 1 is not limited to the above-mentioned example, and steps may be added or the content of the steps may be changed as appropriate. For example, in the above-mentioned example, the center point data 2a of the upper and lower tilt measurement jigs 40 are compared with each other in the measurement step S204, but a point other than the center point data 2a may be used as long as it is possible to compare the same point (for example, a point at the end of the mark 32) on the point cloud data 2 of the upper and lower tilt measurement jigs 40.

[0085] Furthermore, in the above example, two inclination measurement jigs 40 are provided for one steel frame column 6, but the present invention is not limited to the above example, and three or more inclination measurement jigs 40 may be provided. Furthermore, in the above example, multiple inclination measurement jigs 40 are arranged one above the other, but any direction can be used as the direction in which each inclination measurement jigs 40 is arranged. For example, multiple inclination measurement jigs 40 can be arranged on the left and right of a structure that extends in the horizontal direction, such as a beam. In this case, the point cloud data 2 of the inclination measurement jigs 40 can be used to measure the horizontal inclination of the beam.

[0086] Furthermore, the orientation of the marker portion 42 of the tilt measurement jig 40 is not limited to the above example and can be changed as appropriate depending on the shape and arrangement of the steel column 6 and the surrounding conditions. In the example shown in FIG. 12, the back surface (the surface facing diagonally downward) of the marker portion 42 of the upper tilt measurement jig 40 is oriented toward the unmanned aerial vehicle 10. In this case, the unmanned aerial vehicle 10 can capture an image of the marker portion 42 from a position lower than the tilt measurement jig 40. As shown in FIG. 12, the tilt measurement jig 40 according to this embodiment has marks 32 formed on both sides of the marker portion 42. This allows image data to be acquired whether the unmanned aerial vehicle 10 is positioned higher or lower than the tilt measurement jig 40. Note that instead of the example in which the marks 32 are formed on both sides of the marker portion 42, the marks 32 may be formed on only one surface (e.g., the front surface) of the marker portion 42.

[0087] Furthermore, in the above example, measurement is performed using point cloud data 2 of mark 32 formed on marker portion 42 of tilt measurement jig 40, but measurement can also be performed using point cloud data 2 of mark 32 formed on mounting portion 41. In this case, the imaging direction of camera 11 of unmanned aerial vehicle 10 is set to a direction directly facing mark 32 on mounting portion 41 (horizontal plane).

[0088] A tilt measurement jig 40A according to a modified example will be described below with reference to Figure 13. The tilt measurement jig 40A shown in Figure 13(a) differs from the tilt measurement jig 40 in that a marker portion 42 is provided on only one of the first portion 41a and the second portion 41b (second portion 41b in the illustrated example). Furthermore, the marker portion 42 has marks 32 formed on both sides.

[0089] In the image data acquisition process S202, when an image of the marker portion 42 is taken from the front using the unmanned aerial vehicle 10, the tilt measurement jig 40A can be attached to the steel column 6 in the position shown in Figure 13(a), and image data can be acquired in the same way as when the tilt measurement jig 40 of the first embodiment is used.

[0090] On the other hand, when it is necessary to image the marker unit 42 from the right using the unmanned aerial vehicle 10, as shown in FIG. 13(b), the tilt measurement jig 40A is attached to the steel column 6 with its orientation reversed from that of the example shown in FIG. 13(a), thereby making it possible to image the marker unit 42 from the right. In the example shown in FIG. 13(b), the angle of the marker unit 42 is adjusted so that the back surface of the mark 32 faces diagonally upward. As described above, even when the tilt measurement jig 40A is used, the tilt of the steel column 6 can be inspected in substantially the same manner as when the tilt measurement jig 40 is used.

[0091] Furthermore, the tilt measurement jig 40 (tilt measurement jig 40A) can have a configuration that is not limited to the above-described example, and can be modified as appropriate. For example, in the above-described example, the mark 32 is also provided on the mounting portion 41, but a configuration in which the mark 32 is not provided on the mounting portion 41 can also be employed.

[0092] In the above example, the mark 32 is provided on the tilt measurement jig 40, but the present invention is not limited to the above example. For example, the tilt measurement jig 40 may be provided with a pattern (checkered pattern) of the marker 5 used as a general anti-aircraft marker, as shown in FIG. 6(b). With the above configuration, the tilt of the steel column 6 can be inspected using the point cloud data 2.

[0093] As described above, the measurement system 1 (identification system) according to one embodiment of the present invention is a marker 30 (definition unit) provided on a foundation 3 (installation target) and having a mark 32 capable of defining center point data 2a (reference position) in the point cloud data 2; a data acquisition unit (camera 11, control device 20) capable of acquiring point cloud data 2 of the mark 32; an identification unit (controller 20) that identifies the center point data 2a based on the point cloud data 2 of the mark 32 acquired by the data acquisition unit (camera 11, controller 20); Equipped with The mark 32 is a center point P (reference point) corresponding to the center point data 2a is formed, and the image is divided into four or more regions (a first region 32a, a second region 32b, a third region 32c, and a fourth region 32d) by a plurality of boundaries tangent to the center point P; The plurality of regions are of different colors and include at least two pairs of regions that are in a relationship of complementary hues or hues similar to complementary hues.

[0094] This configuration can improve the accuracy of identifying the center point data 2a in the point cloud data 2. That is, in the point cloud data 2 of the mark 32, the center point data 2a is a color (close to gray) different from other parts in the point cloud data 2 as a result of combining the colors of two pairs of areas that are roughly complementary to each other. This makes it possible to improve the accuracy of identifying the center point data 2a in the point cloud data 2.

[0095] Moreover, the mark 32 is The pair of regions having a relationship of complementary hues or hues similar to complementary hues is formed by the regions that are not adjacent to each other across the boundary line.

[0096] This configuration can further improve the accuracy of identifying the center point data 2a in the point cloud data 2. That is, by setting the hues of areas that are not adjacent to each other across a boundary line in the point cloud data 2 to be approximately complementary colors, only the center point data 2a can be set to a color (gray) that is a combination of colors that are approximately complementary colors, thereby improving the identification of the center point data.

[0097] Moreover, the mark 32 is A set of the regions having a relationship of complementary hues or hues similar to complementary hues is formed by the regions adjacent to each other with the boundary line interposed therebetween.

[0098] With this configuration, the accuracy of identifying the center point data 2a in the point cloud data 2 can be improved.

[0099] In addition, the measurement system 1 The present invention provides a flying unmanned aerial vehicle (10), The data acquisition unit (control device 20) Based on the image data (information) acquired by the unmanned aerial vehicle 10, point cloud data 2 of the mark 32 is acquired.

[0100] With this configuration, the center point data 2a can be identified based on image data acquired using the unmanned aerial vehicle 10.

[0101] As described above, the marker 30 (defining portion) according to one embodiment of the present invention is A marker 30 having a mark 32 capable of defining center point data 2a in point cloud data 2 acquired by a predetermined data acquisition unit (control device 20), The mark 32 is a center point P corresponding to the center point data 2a is formed, and the image is divided into four or more regions (a first region 32a, a second region 32b, a third region 32c, and a fourth region 32d) by a plurality of boundaries tangent to the center point P; The plurality of regions are of different colors and include at least two pairs of regions that are in a relationship of complementary hues or hues similar to complementary hues.

[0102] With this configuration, the accuracy of identifying the center point data 2a in the point cloud data 2 can be improved.

[0103] Moreover, the measurement system 1A (tilt measurement system) according to one embodiment of the present invention is A tilt measurement system for measuring the tilt of a steel column 6 (structure), At least two tilt measurement jigs 40 are provided and attached to different positions of the steel column 6; a data acquisition unit (camera 11, control device 20) capable of acquiring point cloud data of the tilt measurement jig 40; an inclination measurement unit (control device 20) that measures the inclination of the steel column 6 based on the point cloud data 2 of the inclination measurement jig 40 acquired by the data acquisition unit; It is equipped with the following.

[0104] This configuration allows for accurate and relatively easy measurement of the inclination of the steel column 6. That is, it is possible to prevent the measurer from reading the scale of a ruler on a jig placed relatively high up, as occurs when using surveying equipment such as a transit, or from measuring the same steel column multiple times in different directions, so that the inclination of the steel column 6 can be measured accurately and relatively easily.

[0105] In addition, measurement system 1A is The present invention provides a flying unmanned aerial vehicle (10), The data acquisition unit The unmanned aerial vehicle 10 is used to acquire point cloud data 2 of the tilt measurement jig 40.

[0106] With this configuration, the inclination of the steel column 6 can be measured based on the point cloud data 2 acquired using the unmanned aerial vehicle 10.

[0107] Further, a tilt measurement method according to an embodiment of the present invention includes: A tilt measurement method for measuring the tilt of a steel column 6, An installation process (installation process S201) of installing at least two or more tilt measurement jigs 40 at different positions on the steel column 6; a data acquisition step (image data acquisition step S202, point cloud data generation step S203) for acquiring point cloud data 2 of the tilt measurement jig 40 by a data acquisition unit (camera 11, control device 20); a measurement step S204 of measuring the inclination of the steel column 6 based on the point cloud data 2 of the inclination measurement jig 40 acquired by the data acquisition unit (camera 11, control device 20); It is equipped with the following.

[0108] With this configuration, the inclination of the steel column 6 can be measured accurately and relatively easily.

[0109] Further, the data acquisition unit The point cloud data 2 of the tilt measurement jig 40 is acquired using a flyable unmanned aerial vehicle 10.

[0110] With this configuration, the inclination of the steel column 6 can be measured based on the point cloud data 2 acquired using the unmanned aerial vehicle 10.

[0111] Moreover, the tilt measurement jig 40 according to one embodiment of the present invention is A tilt measurement jig 40 for measuring the tilt of a steel column 6, A mounting portion 41 that can be attached to any location of the steel column 6; a marker unit 42 (definition unit) connected to the mounting unit 41 and having a mark 32 capable of defining center point data 2a (reference position) using point cloud data 2 acquired by a predetermined data acquisition unit (camera 11, control device 20); It is equipped with the following.

[0112] With this configuration, the inclination of the steel column 6 can be measured accurately and relatively easily.

[0113] The marker portion 42 is The mark 32 is rotatably connected to the mounting portion 41, and the orientation of the mark 32 can be changed to any desired direction.

[0114] With this configuration, the orientation of the mark 32 can be changed depending on the shape and arrangement of the steel column 6 and the surrounding conditions, making it possible to measure the inclination of the steel column 6 more effectively, accurately, and relatively easily.

[0115] The marker portion 42 is The mounting portion 41 is connected to the mounting portion 41 so as to be rotatable in a predetermined direction. The marker portion 42 has the mark 32 on both sides thereof in the predetermined direction.

[0116] With this configuration, the reference position can be determined regardless of whether the height position of the unmanned aerial vehicle 10 is higher or lower than the tilt measurement jig 40, so the tilt of the steel column 6 can be measured more effectively, accurately, and relatively easily.

[0117] The structure is a steel column 6, The mounting portion 41 is It is configured to be removable from the steel column 6 using magnetic force.

[0118] Such a configuration makes it possible to easily handle the inclination measurement jig 40, and to more effectively measure the inclination of the steel column 6 with high accuracy and relatively easily.

[0119] In addition, the mounting portion 41 is It has two mounting surfaces that are formed in a substantially L-shape in plan view, Each mounting surface is They are attached to each of the two horizontally adjacent side surfaces of the steel column 6.

[0120] Such a configuration makes it easier to position the inclination measuring jig 40 relative to the steel column 6 (steel column), and the inclination of the steel column 6 can be measured more effectively, accurately, and relatively easily.

[0121] The measurement system 1 according to this embodiment is one form of an identification system according to the present invention. The measurement system 1A according to this embodiment is one form of the tilt measurement system according to the present invention. The center point data 2a according to this embodiment is one form of the reference position according to the present invention. The center point P according to this embodiment is one form of the reference point according to the present invention. The defining portion according to this embodiment is one form of the marker 30 and the marker portion 42 according to the present invention. The control device 20 according to this embodiment is one form of the identification unit and tilt measurement unit according to the present invention. Moreover, the camera 11 and the control device 20 according to this embodiment are one form of the data acquisition unit according to the present invention.

[0122] Although the embodiment of the present invention has been described above, the present invention is not limited to the above configuration, and various modifications are possible within the scope of the invention described in the claims.

[0123] For example, in each of the above embodiments, an example has been shown in which point cloud data 2 is generated based on image data acquired using the unmanned aerial vehicle 10, but the present invention is not limited to this, and image data can also be acquired without using the unmanned aerial vehicle 10. In this case, for example, a camera capable of acquiring GPS information may be installed on the ground, and point cloud data 2 may be generated based on image data acquired using the camera.

[0124] Furthermore, in each of the above embodiments, an example has been shown in which the point cloud data 2 is generated using image data through SfM processing, but the present invention is not limited to this. For example, a configuration in which the point cloud data 2 is generated using a laser may also be employed. In this case, a laser scanner may be mounted on the unmanned aerial vehicle 10.

[0125] Furthermore, in the present embodiment, an example has been shown in which a structure such as a building is used as the measurement target, but the measurement target is not limited to this. Various objects can be used as the measurement target. [Explanation of symbols]

[0126] 1. 1A Measurement System 10 Unmanned aerial vehicle 20 Control device 30 markers 40 Tilt measurement jig

Claims

1. A tilt measurement system for measuring the tilt of a structure, comprising: At least two tilt measurement jigs are provided and attached to different positions of the structure; a data acquisition unit capable of acquiring point cloud data of the tilt measurement jig; a tilt measurement unit that measures the tilt of the structure based on the point cloud data of the tilt measurement jig acquired by the data acquisition unit; Equipped with Tilt measurement system.

2. Equipped with a flyable unmanned aerial vehicle, The data acquisition unit acquiring point cloud data of the tilt measurement jig using the unmanned aerial vehicle; The tilt measurement system according to claim 1 .

3. A tilt measurement method for measuring the tilt of a structure, comprising: an attachment step of attaching at least two tilt measurement jigs to different positions on the structure; a data acquisition step of acquiring point cloud data of the tilt measurement jig by a data acquisition unit; a measuring step of measuring the inclination of the structure based on the point cloud data of the inclination measurement jig acquired by the data acquisition unit; Equipped with Tilt measurement method.

4. The data acquisition unit Acquiring point cloud data of the tilt measurement jig using a flyable unmanned aerial vehicle; The tilt measurement method according to claim 3 .

5. A tilt measurement jig for measuring the tilt of a structure, a mounting portion that can be attached to any location of the structure; a defining unit connected to the mounting unit and having a mark that can define a reference position based on point cloud data acquired by a predetermined data acquisition unit; Equipped with Tilt measurement jig.

6. The defining unit is The mark is rotatably connected to the mounting portion, and the orientation of the mark can be changed to any direction. The tilt measurement jig according to claim 5 .

7. The defining unit is The mounting portion is connected to the mounting portion so as to be rotatable in a predetermined direction. The mark is provided on both sides of the defining portion in the predetermined direction. The tilt measurement jig according to claim 6 .

8. The structure is a steel column, The mounting portion is The steel column is configured to be removable using magnetic force. The tilt measurement jig according to claim 5 .

9. The mounting portion is The mounting surface has two mounting surfaces that are formed in a substantially L-shape in a plan view. Each mounting surface is Attached to each of two horizontally adjacent sides of the steel column, The tilt measurement jig according to claim 8 .

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