Work device

Abstract

To more easily scan an inner circumference of a structure having a semi-cylindrical shape.SOLUTION: A work device used to scan a tunnel T having a semi-cylindrical shape includes a laser tracker 3 that scans an inner circumference of the tunnel T to acquire coordinate data of a measurement point P, and a control device 7 that controls the scanning by the laser tracker 3. The control device 7 includes a reference position determination unit 716 that determines a reference position CS in the tunnel T based on the coordinate data of the characteristic shape of the inner circumference Ta of the tunnel T acquired by the laser tracker 3, and a three-dimensional shape data generation unit 717 that generates three-dimensional shape data showing an actual shape of the tunnel T based on the reference position CS, using the coordinate data of a plurality of measurement points P set on the inner circumference Ta of the tunnel T. The characteristic shape is located on a plane A perpendicular to a central axis CX along the longitudinal direction of the tunnel T, and is formed to have a range in the circumferential direction around the central axis CX.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a working device used for scanning a structure having a semi-cylindrical shape, such as a tunnel. [Background technology]

[0002] One such technology for scanning the inner circumference of a semi-cylindrical structure such as a tunnel involves moving an inspection tool supported by a movable arm along the inner circumference of the tunnel to check for any abnormalities on the inner circumference.

[0003] When the inspection tool is moved along the inner circumference of the tunnel, the arm is operated so that the inspection tool passes through the teaching points indicating the destination of the inspection tool in order. At this time, the inspection tool moves along a trajectory consisting of a plurality of teaching points while leaving a predetermined gap between the inspection tool and the inner circumference of the tunnel.

[0004] When the teaching points are set from the three-dimensional shape data (3D-CAD data) of the tunnel design, moving the inspection tool according to the teaching points may cause the inspection tool to come into contact with the inner circumference of the tunnel, which may hinder the movement of the inspection tool. This is because the actual shape of a tunnel is affected by vibrations during construction and deterioration over time, and does not necessarily match the shape specified by the 3D design data.

[0005] Patent Document 1 discloses a technology in which three-dimensional shape data showing the actual shape of a tunnel is obtained using a 3D scanner, and teaching points are corrected based on the error with respect to the three-dimensional shape data of the tunnel design. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent Publication No. 2021-098977 Summary of the Invention [Problem to be solved by the invention]

[0007] In Patent Document 1, in order to calculate the above error, it is necessary to align the 3D shape data showing the actual shape of the tunnel with the 3D shape data of the tunnel design. Furthermore, in order to correct the teaching points, it is necessary to identify the position of the inspection device inside the tunnel. For this reason, multiple target markers are installed inside the tunnel, and the positions of the target markers included in the acquired 3D shape data are used to align the design 3D shape data. Furthermore, after measuring the 3D shape, reflectors are installed in place of the target markers, and the distance to each reflector is calculated from a distance measuring device whose positional relationship with the inspection device is known, and the position of the inspection device inside the tunnel is identified from the calculated distance to each reflector.

[0008] Here, the installation of the target marker and the replacement of the target marker with a reflector are performed by an operator, which requires labor and time. Therefore, there is a demand for a method that makes it easier to scan the inner circumference of a semi-cylindrical structure such as a tunnel. In addition to such requirements, another objective of the present invention is to achieve actions and effects derived from the configurations disclosed in the "Form for implementing the invention" described below, which actions and effects cannot be obtained with conventional technologies. [Means for solving the problem]

[0009] The present invention relates to A working device used to scan a structure having a semi-cylindrical shape, comprising: a coordinate data acquisition device that scans the inner periphery of the structure and acquires coordinate data of measurement points; A control device for controlling scanning by the coordinate data acquisition device, The control device includes: a reference position determination unit that determines a reference position within the structure based on the coordinate data of the characteristic shape of the inner periphery of the structure acquired by the coordinate data acquisition device; a three-dimensional shape data generating unit that generates actual three-dimensional shape data of the structure using coordinate data of a plurality of measurement points set on an inner periphery of the structure as the reference position reference, The characteristic shape is positioned on a plane perpendicular to a central axis along the longitudinal direction of the structure, and is formed to have a range in the circumferential direction around the central axis. Effect of the Invention

[0010] According to the present invention, scanning of the inner circumference of a structure having a semi-cylindrical shape can be performed more easily. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram illustrating a schematic configuration of a tunnel inspection system. [Diagram 2] FIG. 1 is a diagram illustrating a tunnel inspection system. [Diagram 3] FIG. 1 is a diagram illustrating a tunnel inspection system. [Figure 4] FIG. 1 is a diagram illustrating a tunnel inspection system. [Diagram 5] FIG. 13 is a diagram illustrating inspection using an inspection tool. [Figure 6] FIG. 2 is a diagram illustrating an example of a characteristic shape. [Figure 7] FIG. 4 is a diagram illustrating a scanning range. [Figure 8] FIG. 13 is a conceptual diagram illustrating the determination of a reference position. [Figure 9] 11 is a flowchart illustrating a process of generating three-dimensional shape data of a tunnel. [Figure 10] 13 is a flowchart illustrating a process of determining a reference position. [Figure 11] FIG. 13 is a diagram illustrating a scanning range for shape measurement. [Figure 12] FIG. 13 is a diagram illustrating a scanning range for shape measurement. [Figure 13] 11A to 11C are diagrams for explaining generation of three-dimensional shape data based on a reference position. [Figure 14]11A to 11C are diagrams for explaining generation of three-dimensional shape data based on a reference position. [Figure 15] 11 is a flowchart illustrating a process for inspecting a tunnel using an inspection tool. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment of the present invention will be described by taking as an example a case where it is applied to a tunnel inspection system 1 that scans a tunnel. This tunnel inspection system 1 includes a working device (an inspection device 2 and a laser tracker 3) that is used to scan a tunnel T having a semi-cylindrical shape. Here, the tunnel is a structure having a semi-cylindrical shape in cross section. In this specification, "scanning" of a structure having a semi-cylindrical shape includes scanning by the laser tracker 3 for measuring the shape of the inner circumference of the structure and scanning by the inspection tool 25 for inspecting the structure. FIG. 1 is a diagram illustrating a schematic configuration of a tunnel inspection system 1. As shown in FIG. 2 to 4 are diagrams illustrating the tunnel inspection system 1. FIG. FIG. 5 is a diagram for explaining inspection using an inspection tool. 2 to 4, examples of the arrangement of the inspection device 2 and the laser tracker 3 inside the tunnel T are shown together with a vehicle V equipped with the inspection device 2 and the laser tracker 3. Fig. 2 shows a schematic cross section of tunnel T cut along a plane along the longitudinal direction of tunnel T. Fig. 3 shows a schematic view of the inside of tunnel T as viewed from above. Fig. 4 shows a schematic cross section of tunnel T cut along a plane perpendicular to the longitudinal direction of tunnel T.

[0013] In the following description, the positional relationship of each component in tunnel T will be described based on the X, Y, and Z directions shown in Fig. 2 as necessary. The X direction in Fig. 2 corresponds to the width direction of tunnel T. The Y direction corresponds to the longitudinal direction of tunnel T. The Z direction corresponds to the direction perpendicular to the floor surface GD in tunnel T (vertical direction).

[0014] As shown in FIG. 1, a tunnel inspection system 1 includes an inspection device 2 that inspects a tunnel T, a laser tracker 3 (distance measuring device) that measures the distance to an object within the tunnel T, and a control device 7. The movement of the inspection tool 25 by the inspection device 2, and the inspection by the inspection tool 25 and the scanning by the laser tracker 3 are controlled by the control device 7.

[0015] As shown in Fig. 2, the inspection device 2 and the laser tracker 3 are mounted on a vehicle V (mobile body) that can travel inside the tunnel T. The vehicle V has a lifting table 50 supported by a lifting mechanism 5. The inspection device 2 and the laser tracker 3 are mounted on a first support base 52 on the lifting table 50. The lifting table 50 can be raised and lowered in the Z direction by a drive device (not shown) provided in the lifting mechanism 5 (see Figs. 2 and 4).

[0016] As shown in FIG. 3, the first support base 52 is supported by guide rails 51, 51 provided on the lift table 50. 3, the guide rails 51, 51 extend linearly in the longitudinal direction of the vehicle V (left-right direction in the figure) on the upper surface of the lifting table 50. The guide rails 51, 51 are provided parallel to each other in a top view. The first support base 52 is movable in the front-rear direction of the vehicle V along the guide rails 51, 51 by the driving force of a driving mechanism (not shown). When the vehicle V is arranged inside the tunnel T oriented along the longitudinal direction of the tunnel T (left and right direction in the figure), the first support stand 52 is movable back and forth in the Y direction along the longitudinal direction of the tunnel T.

[0017] On the first support stand 52, the laser tracker 3 is provided on the rear side of the vehicle V. As shown in Fig. 4, in this state, the laser tracker 3 is rotatable about two axes (a vertical line VL and a horizontal line HL) that are perpendicular to each other. 3, a base 53 is provided on the first support base 52 on the front side of the vehicle V. The base 53 is a plate-like member extending in the width direction (X direction) of the vehicle V. When viewed from above, the base 53 has a substantially rectangular shape. The base 53 is fixed to the upper surface of the first support base 52. One end 53a and the other end 53b of the base 53 in the longitudinal direction have a length L53 in the X direction that falls within the range of the width W of the vehicle V.

[0018] Guide rails 54, 54 are provided on the upper surface of the base 53. The guide rails 54, 54 extend linearly on the upper surface of the base 53 in the width direction of the vehicle V (vertical direction in the figure). The guide rails 54, 54 are provided parallel to each other when viewed from above. A second support base 55 on which the inspection device 2 is mounted is supported by the guide rails 54, 54. The second support base 55 is movable in the width direction of the vehicle V along the guide rails 54, 54 by the driving force of a driving mechanism (not shown). When the vehicle V is arranged inside the tunnel T oriented along the longitudinal direction of the tunnel T (left and right direction in the figure), the second support stand 55 is movable back and forth in the X direction along the width direction of the tunnel T.

[0019] The inspection device 2 mounted on the second support base 55 is movable in the width direction of the vehicle V together with the second support base 55. In vehicle V, when the first support base 52 is displaced in the fore-and-aft direction of vehicle V, the laser tracker 3 mounted on the first support base 52 and the inspection device 2 mounted on the second support base 55 are displaced together in the fore-and-aft direction of vehicle V. At this time, the displacement amounts of the inspection device 2 and the laser tracker 3 and the timing at which they start to move are the same. In other words, the inspection device 2 and the laser tracker 3 are displaced in the fore-and-aft direction of vehicle V while maintaining their relative positional relationship.

[0020] Furthermore, when the second support base 55 is displaced in the width direction of the vehicle V, the inspection device 2 is displaced relative to the laser tracker 3 in the width direction of the vehicle V. The amount of displacement of the inspection device 2 at this time can be identified from the drive amount of a drive motor (servo motor) (not shown) that displaces the second support base 55. Therefore, the relative positional relationship between the laser tracker 3 and the inspection device 2 when the second support base 55 is displaced in the X direction can always be identified from the drive amount of the drive motor (servo motor).

[0021] Furthermore, when the lift table 50 is displaced in the Z direction, the laser tracker 3 and the inspection device 2 are displaced together in the Z direction. In this case, the amount of displacement of the inspection device 2 and the laser tracker 3 and the timing at which the displacement starts are the same. In other words, the inspection device 2 and the laser tracker 3 are displaced in the Z direction while maintaining their relative positional relationship.

[0022] As shown in Fig. 1, the inspection device 2 has a support mechanism 20 that supports an inspection tool 25. The support mechanism 20 is a movable arm configured by connecting a plurality of arm portions 21. In this embodiment, as an example, a movable arm having six rotation shafts is adopted. The inspection device 2 includes an actuator 23 that operates the support mechanism 20, and a communication interface (communication IF 24). The communication IF 24 is connected to the control device 7 by wire or wirelessly. The inspection device 2 receives instruction input from the control device 7 described below via the communication IF 24. As an example, the instruction input from the control device 7 includes an operation instruction to place the inspection tool 25 at designated coordinates in the tunnel T and an inspection instruction to perform inspection using the inspection tool 25. Based on the operation instruction, the inspection device 2 drives the actuator 23 to place the inspection tool 25 at designated coordinates within the tunnel T. Furthermore, based on the inspection instruction, the inspection device 2 operates the inspection tool 25 to perform a predetermined inspection.

[0023] Here, the inspection tool 25 can be any inspection equipment used for non-destructive testing, such as a hammer for performing a tapping test on the inner circumference Ta of the tunnel T, or a camera for performing image analysis of the inner circumference Ta of the tunnel T. For example, when the inspection tool 25 is a hammer, the inspection device 2 performs a hammering inspection using the inspection tool 25 (hammer) while moving the inspection tool 25 along the inner circumference Ta of the tunnel T. Data acquired by the inspection (inspection data) is transmitted to the control device 7 via the communication IF 24.

[0024] The laser tracker 3 calculates the distance to the target (measurement point P) in the tunnel T and outputs the coordinate data of each measurement point P in the tunnel T. 1, the laser tracker 3 has a laser light emitting unit 31, a laser light receiving unit 32, an actuator 33, a communication interface (communication IF 34), a storage unit 35, and a control unit 36. These are connected to each other via a bus 37.

[0025] 1, the irradiating unit 31 irradiates laser light toward a measurement point P set on the inner circumference Ta of the tunnel T. The light receiving unit 32 receives the laser light reflected at the measurement point P. The communication IF 34 is connected to the control device 7 by wire or wirelessly. The storage unit 35 is a recording medium capable of retaining and rewriting information, such as an HDD, an SSD, or a memory. The storage unit 35 stores programs for each process executed by the control unit 36. Furthermore, the storage unit 35 stores information generated during the process. The control unit 36 ​​is a processor such as a CPU or a GPU, and performs processing defined by the program based on the program stored in the storage unit 35.

[0026] The control unit 36 ​​has a measurement control unit 361 and a position information calculation unit 362 as functional blocks.

[0027] The measurement control unit 361 has a function of adjusting the direction of the laser light emitted from the irradiation unit 31 and a function of controlling the irradiation timing of the laser light from the irradiation unit 31. In this embodiment, a plurality of measurement points P are set on the inner circumference Ta of the tunnel T. The measurement control unit 361 drives the actuator 33 to change the orientation of the irradiation unit 31 in order to irradiate the laser light toward the set measurement points P in sequence. Specifically, the measurement control unit 361 rotates the laser tracker 3 using the actuator 33 around two mutually perpendicular axes (the vertical line VL and the horizontal line HL) so that the direction of the laser light (the irradiation point of the laser light) passes through the set measurement points P in sequence. At this time, the measurement control unit 361 causes the irradiation unit 31 to irradiate the laser light at a timing when the set measurement point P is located on an extension of the direction of the laser light. As a result, a plurality of measurement points P set on the inner circumference Ta of the tunnel T are irradiated with the laser light in sequence.

[0028] The position information calculation unit 362 has a function of calculating the distance to each measurement point P and a function of generating coordinate data of each measurement point P. Specifically, the position information calculation unit 362 compares the laser light emitted from the irradiation unit 31 with the laser light received by the light receiving unit 32, and calculates the relative distance between the laser tracker 3 and each measurement point P from the time from emission of the laser light to reception of the laser light. Furthermore, it specifies the direction of each measurement point P with respect to the laser tracker 3. Furthermore, the position information calculation unit 362 calculates coordinate data of the measurement point P in three-dimensional space based on the laser tracker 3 from the relative distance between the laser tracker 3 and each measurement point P and the direction of each measurement point P based on the laser tracker 3. Here, the coordinate data of the measurement point P is coordinate data (coordinate data in the sensor coordinate system) based on the laser tracker 3 in the three-dimensional space (XYZ space) inside the tunnel T.

[0029] The calculated coordinate data of each measurement point P is transmitted to the control device 7 via the communication IF 34. The calculated coordinate data of each measurement point P may be stored in the storage unit 35. Furthermore, instead of the coordinate data of each measurement point P, data indicating the distance (relative distance) to each measurement point P may be transmitted directly to the control device 7. In addition to the coordinate data of each measurement point P, data indicating the distance (relative distance) to each measurement point P may also be transmitted to the control device 7.

[0030] The control device 7 includes a processing unit 71, a storage unit 72, an input / output port (I / O) 73, and a communication interface (communication IF 74). The processing unit 71, the storage unit 72, the input / output port 73, and the communication IF 74 are connected to each other via a bus 75. An input device 76 and an output device 77 are connected to the input / output port 73 .

[0031] The control device 7 may be mounted on the vehicle V together with the inspection device 2 and the laser tracker 3. Also, it may be installed in the tunnel T separately from the inspection device 2 and the laser tracker 3. The control device 7 may be a stationary terminal operated by an operator, or may be a portable terminal carried by the operator. Note that it may be another terminal that can be connected to the inspection device 2 and the laser tracker 3 via the network NT. Furthermore, the control device 7 may be a control device attached to the inspection device 2 and the laser tracker 3.

[0032] The communication IF 74 is connected to the communication IF 24 of the inspection device 2 and the communication IF 34 of the laser tracker 3 wirelessly or via a wire. Furthermore, the communication IF 74 is connected to an external server, other terminals, etc. via the network NT.

[0033] The input device 76 is, for example, an interface for inputting instructions to the control device 7. Examples of the input device 76 include a keyboard, a mouse, a touch panel, and a terminal carried by an operator. The output device 77 is, for example, an interface for outputting information such as characters, images, and voices. Examples of the output device 77 include a monitor, a speaker, and a terminal carried by a worker.

[0034] The processing unit 71 is a processor such as a CPU or a GPU, and executes processing defined by a program based on a program stored in the storage unit 72. The storage unit 72 is a recording medium capable of retaining and rewriting information, such as an HDD, an SSD, or a memory. The storage unit 72 stores programs for each process executed by the processing unit 71. Furthermore, the storage unit 72 temporarily stores information generated during the process. The function of the storage unit 72 may be provided in an external server connected to the control device 7 via the network NT.

[0035] The tunnel inspection system 1 has the following representative functions: (a) The laser tracker 3 measures the distance to multiple measurement points P set inside the tunnel T, and acquires the coordinate data of each measurement point P. (b) Based on the acquired coordinate data, a reference position CS within the tunnel T is determined. (c) Based on the acquired coordinate data, three-dimensional shape data (point cloud data) showing the actual shape of the inner periphery Ta of the tunnel T is generated. (d) Calculate the error between the three-dimensional shape data showing the actual shape of the inner circumference Ta of the tunnel T and the three-dimensional shape data generated from the design CAD data. (e) The movement trajectory ML of the inspection tool 25 is corrected in accordance with the calculated error. (f) Inspection is performed using the inspection tool 25 while moving the inspection tool 25 along the movement trajectory ML.

[0036] The processing unit 71 of the control device 7 executes processes for realizing the above-mentioned functions based on the programs stored in the storage unit 72. The processing unit 71 has, as functional blocks, a drive control unit 711, a teaching point setting unit 712, a teaching point correction unit 713, a scanning range setting unit 714, a scanning control unit 715, a reference position determination unit 716, and a three-dimensional shape data generation unit 717.

[0037] The drive control unit 711 generates an operation command for moving the inspection tool 25 along a movement trajectory ML (see (b) and (c) of FIG. 5) when performing inspection with the inspection tool 25. Specifically, the drive control unit 711 generates an operation command for the support mechanism 20 that supports the inspection tool 25. 2 and 3, the drive control unit 711 controls the lifting and lowering of the first support stand 52 by driving the lifting mechanism 5, the movement of the first support stand 52 in the front-rear direction of the vehicle, and the movement of the second support stand 55 in the width direction of the vehicle. The lifting and lowering of the first support stand 52 and the movement of the first support stand 52 and the second support stand 55 are performed by outputting an operation command to a drive mechanism (not shown).

[0038] The teaching point setting unit 712 sets teaching points MP that indicate the movement destinations of the inspection tool 25 when inspecting the inner circumference Ta of the tunnel T. The teaching point setting unit 712 sets a movement trajectory ML of the inspection tool 25 when inspecting the inner circumference Ta of the tunnel T from the multiple teaching points MP that have been set (see (b) and (c) of FIG. 5). The movement trajectory ML (see (b) and (c) of FIG. 5) is generated based on the three-dimensional design shape data (CAD data) of the tunnel T. The movement trajectory ML may be generated by an external device or the like based on the three-dimensional design shape data of the tunnel T. In this case, the movement trajectory ML generated by the external device is stored in the memory unit 72, and the teaching point setting unit 712 reads out and uses the movement trajectory ML stored in advance in the memory unit 72. The movement trajectory ML generated by the external device may also be stored in an external server, and the teaching point setting unit 712 may acquire and use the movement trajectory ML stored in the external server via the network NT.

[0039] The teaching point correction unit 713 calculates an error between the three-dimensional shape data (point cloud data) indicating the actual shape of the inner periphery Ta of the tunnel T and the design three-dimensional shape data. In accordance with the calculated error, the movement trajectory ML of the inspection tool 25 generated from the design three-dimensional shape data is corrected.

[0040] The scanning range setting unit 714 sets a plurality of measurement points P on the inner circumference Ta of the tunnel T. In this embodiment, when determining the reference position CS in the tunnel T and when generating three-dimensional shape data showing the actual shape of the tunnel T, a plurality of measurement points P are set within the scanning range.

[0041] The scanning control unit 715 generates an operation command for operating the laser tracker 3. As an example, the operation command is a command for operating the laser tracker 3 so that the direction of the laser light irradiated from the irradiation unit 31 (the irradiation point of the laser light) passes through the set measurement points P in order. The scanning control unit 715 outputs the generated operation command to the laser tracker 3. As a result, the laser tracker 3 is rotated around two mutually perpendicular axes (the vertical line VL and the horizontal line HL) by the actuator 33 driven based on the operation command, and the pointing direction of the laser light is controlled so as to pass through the set measurement points P in order. Furthermore, the scanning control unit 715 generates a command to irradiate laser light from the irradiation unit 31 at the timing when the set measurement point P is located on an extension of the direction of the laser light, and transmits the command to the laser tracker 3 side. As a result, a plurality of measurement points P set on the inner circumference Ta of the tunnel T are irradiated with the laser light in sequence.

[0042] The reference position determination unit 716 calculates coordinate data of each measurement point P in a coordinate system based on the laser tracker 3 from the distance to each measurement point P (target) set in the tunnel T. The reference position determination unit 716 determines a reference position CS in the tunnel T from the calculated coordinate data of each measurement point P. The three-dimensional shape data generator 717 generates three-dimensional shape data (point cloud data) indicating the actual shape of the inner periphery Ta of the tunnel T based on the coordinate data of each measurement point P. Furthermore, the three-dimensional shape data generator 717 acquires three-dimensional shape data (point cloud data) indicating the actual shape of the inner periphery Ta of the tunnel T as three-dimensional shape data based on a reference position CS within the tunnel T. Here, the three-dimensional shape data based on the reference position CS is coordinate data in a tunnel coordinate system that can be compared with the designed three-dimensional shape data.

[0043] An example of the processing in the control device 7 will now be described in detail. 6 is a diagram illustrating an example of a characteristic shape, in which a boundary line Tj of a connection portion J of the tunnel structures Tx and Tx, and a recess 10 are shown. Fig. 7 is a diagram for explaining the scanning range, which is set when determining the reference position CS for measurement inside the tunnel, and the measurement points P included in the scanning range are typically shown. Fig. 8 is a conceptual diagram for explaining the determination of the reference position CS. Fig. 8 is a conceptual diagram for explaining the process of determining a virtual circle Im perpendicular to the central axis CX of the tunnel T from the deepest point Pd (Pd1 to Pd7) of each scanning range and determining the center of the calculated virtual circle Im as the reference position CS of the tunnel T.

[0044] In the tunnel inspection system 1, a movement trajectory ML (see FIGS. 5(b) and 5(c)) of the inspection tool 25 is set based on three-dimensional design shape data (CAD data) of the tunnel T. Here, the actual shape of the tunnel T is affected by vibrations during the construction stage, deterioration over time, and the like, and does not necessarily match the shape specified by the three-dimensional design shape data.

[0045] Therefore, three-dimensional shape data (point cloud data) showing the actual shape of the inner circumference Ta of the tunnel T is acquired, the error between the acquired three-dimensional shape data and the designed three-dimensional shape data is calculated, and the movement trajectory ML of the inspection tool 25 is corrected as necessary. In order to calculate the error, it is necessary to align the acquired three-dimensional shape data with the three-dimensional shape data in the design.

[0046] In conventional methods, markers for identifying positions were placed inside the tunnel, and positioning was performed using the markers included in the 3D shape data. In this embodiment, a reference position CS in the tunnel T is determined using a characteristic shape in the tunnel T. Then, using the determined reference position CS, alignment is performed between the designed three-dimensional shape data and the acquired three-dimensional shape data.

[0047] [Determination of reference position CS] 8, the tunnel T is configured by lining up a plurality of cylindrical tunnel structures Tx in the longitudinal direction of the tunnel T. Therefore, on the inner circumference Ta of the tunnel T, connections between the tunnel structures Tx appear periodically at intervals in the longitudinal direction of the tunnel T. At a connection J between a certain tunnel structure Tx and another tunnel structure Tx adjacent to this tunnel structure Tx, a boundary line Tj appears as a joint (see FIG. 6). This boundary line Tj is visible inside the tunnel T. Furthermore, in the inner circumference Ta of the tunnel T, the boundary line Tj continues from one side GDa in the width direction of the floor surface GD of the tunnel T through the zenith to the other side GDb, as shown in FIG.

[0048] In this embodiment, attention is paid to the following points. In a tunnel T made up of cylindrical tunnel structures Tx connected together, (a) if a virtual circle Im is drawn with the boundary line Tj as its periphery, the center of the virtual circle Im coincides with the central axis CX of the tunnel structure Tx (tunnel T), and (b) a plane A including the virtual circle Im is perpendicular to the central axis CX of the tunnel T. The position of the boundary line Tj in the longitudinal direction of the tunnel T was adopted as the characteristic shape used to determine the reference position CS within the tunnel T.

[0049] 6, a recess 10 is provided at a connection J of the tunnel structures Tx, Tx of this embodiment. The recess 10 is recessed from the inner circumference Ta of the tunnel T toward the mountain surface side (upper side in the figure). In the recess 10, a distance L10 from the inner circumference Ta of the tunnel T changes continuously in the direction of the central axis CX of the tunnel T (left-right direction in the figure). The recess 10 is formed between an inclined surface 11 provided on one of the adjacent tunnel structures Tx, Tx and an inclined surface 12 provided on the other of the adjacent tunnel structures Tx, Tx. These inclined surfaces 11, 12 are provided symmetrically with respect to the boundary line Tj of the tunnel structures Tx, Tx. The inclined surfaces 11 and 12 are inclined surfaces inclined in a direction such that the distance L10 corresponding to the depth from the inner circumference Ta of the tunnel T increases as the inclined surfaces 11 and 12 approach the boundary line Tj.

[0050] Therefore, in a cross-sectional view along the central axis CX of the tunnel T (left-right direction in the figure), the recess 10 has a deepest point Pd where the distance L10 from the inner circumference Ta of the tunnel T is maximum. This deepest point Pd is at a position intersecting with the boundary line Tj of the tunnel structures Tx, Tx. The deepest points Pd are connected in the circumferential direction around the central axis CX of the tunnel T to form the boundary line Tj.

[0051] In this embodiment, in order to determine a reference position CS in the tunnel T, a recess 10 at a connection J between the tunnel structures Tx, Tx is used as a characteristic shape for determining the reference position CS.

[0052] FIG. 9 is a flowchart illustrating the process of generating three-dimensional shape data showing the actual shape of the tunnel T. Fig. 10 is a flowchart for explaining the process of determining the measurement reference position CP, and is a flowchart for explaining the process of step S101 in Fig. 9 in detail.

[0053] In this embodiment, a process of determining a reference position CP (reference point) for measurement in the tunnel T is performed so as to satisfy the following conditions (step S101). (a) Vehicle V is parked in tunnel T so that the longitudinal direction of vehicle V coincides with the longitudinal direction of the tunnel (the direction of central axis CX) (see FIG. 3). (b) When viewed from the X direction, the laser tracker 3 is positioned so that the central axis (vertical line VL) of the laser tracker 3 coincides with the boundary line Tj.

[0054] Here, the process of step S101 will be specifically described with reference to FIG. First, the scanning range setting unit 714 sets a scanning range for determining a reference position (step S201). Specifically, the scanning range setting unit 714 sets the scanning range in a range crossing the connection portion J (boundary line Tj) of the tunnel structure Tx in the longitudinal direction of the tunnel T (see FIG. 7).

[0055] As shown in Fig. 7, the scanning range is composed of a plurality of measurement points P. In the case of Fig. 7, the scanning range is composed of a plurality of measurement points P1 to P28 connected in a straight line. The scanning range is set to an area that crosses the connection portion (boundary line Tj) of the tunnel structure Tx in the longitudinal direction of the tunnel T (left-right direction in the figure). In this embodiment, the scanning range for determining the reference position is set at a plurality of positions shifted in the circumferential direction of the inner circumference Ta of the tunnel T. 4, for example, a total of seven scanning ranges are set by shifting the positions in the circumferential direction of the inner circumference Ta of the tunnel T. Each of the scanning ranges is set at a different height position h1 to h7 in the Z direction.

[0056] As described above, in this embodiment, scanning to determine the reference position CS is performed in a state in which the vehicle V and the laser tracker 3 are positioned so that the central axis (vertical line VL) of the laser tracker 3 and the boundary line Tj coincide with each other in the longitudinal direction (Y direction) of the tunnel T. Therefore, when the laser tracker 3 is accurately positioned, the pointing direction of the laser tracker 3 can be changed to another scanning range at a different height position by simply rotating the laser tracker 3 in the vertical direction around the horizontal line HL (see Figure 4).

[0057] The total number of scanning ranges to be set is not limited to the embodiment in Fig. 4. It is preferable that the total number of scanning ranges is as large as possible without excessively burdening the processing of the measurement data obtained by scanning. The more scanning ranges are set, the more accurate the reference position CS is determined.

[0058] Next, the scan control unit 715 performs scanning of the scanning range by the laser tracker 3 (step S202). Then, the reference position determination unit 716 measures the distance to each measurement point P included in the scanning range (step S203). In this embodiment, the calculation of the distance to the measurement point P is performed one by one in order from the measurement point P1 located at one end of the scanning range to the measurement point P28 located at the other end.

[0059] When the measurement of the distance to each measurement point P included in the scanning range is completed, in step S204, the scanning control unit 715 checks whether or not the scanning of all the scanning ranges set in step S201 is completed. For example, at the stage where scanning of only the scanning range at the height position h1 of the inner circumference Ta of the tunnel T in Fig. 4 has been completed, it is determined in step S204 that scanning of all scanning ranges has not been completed (step S204, No). In such a case, the process proceeds to the processing of step S202, scanning of the scanning ranges that have not been scanned is performed, and the distance to each measurement point P included in the scanning range is measured (step S203). Therefore, the processes of steps S202 and S203 are repeatedly performed until scanning of all the scanning ranges set in step S201 (scanning ranges of height positions h1 to h7 in FIG. 4) is completed.

[0060] When scanning of all scanning ranges is completed (Yes in step S204), the reference position determining unit 716 identifies the deepest point Pd in ​​each scanning range (step S205).

[0061] As described above, the scanning range is made up of a plurality of measurement points P. As shown in Fig. 7, in the portion of the recess 10 (the portion of the characteristic shape), the distance from the laser tracker 3 to the measurement point P changes significantly. For example, in the case of the scanning range from measurement points P1 to P28, the distance from the laser tracker 3 changes at a substantially constant rate from measurement point P1 to measurement point P10. After passing measurement point P10, the distance from the laser tracker 3 changes significantly. As described above, the distance of the recess 10 from the inner circumference Ta changes continuously in the longitudinal direction of the tunnel T, and at the deepest point, the distance from the inner circumference Ta changes from an increase to a decrease.

[0062] In this embodiment, the reference position determination unit 716 identifies the measurement points in the region corresponding to the recess 10 by comparing the distances to each of the measured measurement points P. In the case of Fig. 7, measurement points P10 to P18 are identified as the measurement points in the region corresponding to the recess 10. Then, of these measurement points P10 to P18, the reference position determination unit 716 determines that the measurement point P14, which is the farthest from the laser tracker 3, is the deepest point Pd of the recessed portion 10. In the case of Figure 7, the measurement point P14 is determined to be the deepest point Pd.

[0063] In the case of Fig. 4, a total of seven scanning ranges with different height positions h1 to h7 are set. Therefore, the deepest points Pd1 to Pd7 are determined for each of the scanning ranges with different height positions h1 to h7.

[0064] Next, the reference position determining unit 716 sets an imaginary circle Im (see FIG. 8) having the determined deepest points Pd (Pd1 to Pd7) on its outer periphery (step S206).

[0065] As shown in Fig. 8, the tunnel T is formed by installing a cylindrical tunnel structure Tx in an excavated hole with a circular cross section to prevent the mountain surface from collapsing, and setting a floor structure 100 that becomes the floor surface GD inside the tunnel structure Tx. Inside the tunnel T, the cylindrical tunnel structures Tx are connected in series in the longitudinal direction of the tunnel T. Therefore, a linear boundary line Tj, which is a joint, is generated at a joint J between the tunnel structures Tx. When viewed from the central axis direction of the tunnel T, the boundary line Tj describes an arc along the inner circumference Ta of the tunnel T.

[0066] When the deepest points Pd (Pd1 to Pd7) of each scanning range set at different height positions h1 to h7 on the inner circumference Ta of the tunnel T are plotted on plane A which is the boundary between the tunnel structures Tx and Tx shown in Fig. 8, a virtual circle Im having an outer periphery of these deepest points Pd (Pd1 to Pd7) can be drawn. Here, the outer periphery of the virtual circle Im corresponds to the boundary line Tj of the tunnel structure Tx, and the area of ​​the virtual circle Im corresponds to the opening area of ​​the tunnel structure Tx. When the virtual circle Im is set (step S206), the reference position determining unit 716 calculates the coordinate data of the center of the virtual circle Im from the coordinates of the deepest points Pd (d1 to d7) of each scanning range (step S207).

[0067] In this embodiment, assuming that the deepest points Pd are located on the same imaginary circle Im surrounding the central axis CX of the tunnel T, the coordinate data of the center of the imaginary circle Im in the cross section of the tunnel T along the boundary line Tj is calculated from the coordinates of each of the deepest points Pd (Pd1 to Pd7). Next, the reference position determining unit 716 determines the center of the virtual circle Im as the reference position CS for measurement (step S208).

[0068] When the reference position for measurement has been determined in this manner, the process returns to the flowchart of FIG. 9 and proceeds to step S102.

[0069] In step S102, the scanning range setting unit 714 sets a scanning range for generating three-dimensional shape data (scanning range for shape measurement). Specifically, the scanning range setting unit 714 sets a plurality of measurement points P on the inner circumference of the tunnel structure Tx on the front side of the vehicle V, based on the current position of the laser tracker 3.

[0070] 11 and 12 are diagrams for explaining the scanning range for shape measurement. FIG. 12 is a development view showing the inner periphery Ta of the tunnel T developed in the circumferential direction around the central axis CX of the tunnel T.

[0071] As described above, when determining the reference position for measurement, the vehicle is positioned so that the laser tracker 3 is located immediately to the side of the boundary line Tj. Here, the term "immediately to the side" in this specification does not only mean "immediately to the side" of the boundary line Tj in the strict sense, but also includes the case where the position is slightly shifted from the side of the boundary line Tj. Therefore, the scanning range setting unit 714 sets a plurality of measurement points P on the inner circumference Ta of the tunnel structure Tx located on one side as viewed from the boundary line Tj. FIG. 11 shows a schematic diagram of a state in which a plurality of measurement points P are set on the inner circumference of a tunnel structure Tx on the front side of a vehicle V.

[0072] As an example, in this embodiment, the scanning range setting unit 714 sets a measurement point sequence PL in which multiple measurement points P are arranged at a predetermined interval Dy in the longitudinal direction (Y direction) of the tunnel T. Furthermore, the scanning range setting unit 714 sets multiple measurement point sequences PL at a predetermined interval Ds in the circumferential direction of the inner circumference Ta of the tunnel T. As a result, multiple measurement point sequences PL1 to PL9 in which multiple measurement points P are arranged in series are set at intervals in the circumferential direction on the inner circumference Ta of the tunnel T. Therefore, multiple measurement points P are set over approximately the entire surface of the inner circumference of the tunnel structure Tx.

[0073] Here, the total number of measurement points P that are set is sufficiently smaller than the number of measurement points when scanning the inner circumference of the tunnel T using a conventionally known 3D scanner.

[0074] Next, the scan control unit 715 generates an operation command for sequentially measuring the distances to the multiple measurement points P set in step S102 (step S103). The generated operation command is transmitted to the laser tracker 3. As a result, the measurement control unit 361 on the laser tracker 3 side rotates the laser tracker 3 by the actuator 33 about two mutually perpendicular axes (the vertical line VL and the horizontal line HL) so that the pointing direction of the laser light (the irradiation point of the laser light) passes through the set measurement points P in order. At this time, the measurement control unit 361 on the laser tracker 3 side irradiates the laser light from the irradiation unit 31 at a timing when the set measurement point P is located on an extension of the direction of the laser light. As a result, a plurality of measurement points P set on the inner circumference Ta of the tunnel T are irradiated with the laser light in sequence.

[0075] In parallel with the irradiation of each measurement point P within the scanning range with the laser light, the position information calculation unit 432 on the laser tracker 3 side calculates the distance to each measurement point P and generates coordinate data of each measurement point P with reference to the laser tracker 3. For this reason, the coordinate data of each measurement point P is continuously input from the laser tracker 3 to the control device 7.

[0076] The three-dimensional shape data generating unit 717 of the control device 7 generates three-dimensional shape data (point cloud data) indicating the actual shape of the inner periphery of the tunnel T from the input coordinate data (step S105).

[0077] 13 and 14 are diagrams for explaining the generation of three-dimensional shape data. Here, the three-dimensional shape data generated in step S105 described above is a collection of coordinate data of each measurement point P within the scanning range. The coordinate data (XYZ coordinates) of each measurement point P is three-dimensional shape data in a sensor coordinate system based on the position of the laser tracker 3.

[0078] In this embodiment, the following process is executed when generating three-dimensional shape data. (A) From a set of coordinate data of each measurement point P within the scanning range for shape measurement, a virtual cylinder Im' inscribed in the inner circumference Ta of the tunnel T is conceived (see FIG. 13). Specifically, consider an imaginary cylinder Im' having each measurement point P on its outer periphery and an axis along the longitudinal direction. (B) The inner radius r and axial direction of a virtual cylinder Im' are estimated from the coordinate data of each measurement point P, and the central axis CX of the virtual cylinder Im' is determined from the estimated axial direction (see Figure 13). (C) The intersection point between the determined central axis CX and the previously determined imaginary circle Im on the surface A, that is, the center of the imaginary circle Im, is set as the reference position CS for alignment.

[0079] Then, the three-dimensional shape data generation unit 717 uses the reference position CS to convert the coordinate data of the measurement point P included in the three-dimensional shape data acquired in step S104 from coordinate data in the sensor coordinate system to coordinate data in the tunnel coordinate system, thereby generating three-dimensional shape data of the tunnel (step S105). As a result, three-dimensional shape data showing the actual shape of the tunnel is generated with reference to the reference position CS. At this time, the inclination of the tunnel structure Tx relative to the central axis CX of the tunnel structure Tx may be calculated from the inner diameter and axial direction of the imaginary cylinder Im', and may be reflected in the three-dimensional shape data.

[0080] The design three-dimensional shape data also includes coordinate data of the boundary line Tj of the tunnel structure. The design three-dimensional shape data can be generated based on the reference position CS for alignment. Therefore, it becomes possible to align the acquired three-dimensional shape data and the design three-dimensional shape data based on the reference position CS.

[0081] The reference position CS may be set on the floor surface GD inside the tunnel T (see FIG. 14). As described above, since the laser tracker 3 is mounted on the vehicle V, the height of the laser tracker 3 from the floor surface GD can be specified. In this embodiment, the installation height is subtracted from the Z component of the coordinate data of the center C based on the position of the laser tracker 3. The coordinate data obtained by this is the coordinate data of the center position of the floor surface GD inside the tunnel T, and becomes the reference position CS' based on the floor surface GD. This reference position CS' is located at the center in the width direction of the floor surface GD, and is located on the same plane A as the boundary line Tj of the tunnel structure Tx. As a result, the straight line L_CX that passes through the reference position CS' and is parallel to the central axis CX becomes a straight line that passes through the center of the width of the floor surface GD and runs along the longitudinal direction of the floor surface GD. Using this straight line L_CX as a reference, the width W (= W / 2 + W / 2) of the floor surface can be calculated. In this way, the reference position CS' set on the floor surface GD also becomes a clear reference position for the longitudinal direction (Y direction) of the tunnel T and the width direction (X direction) of the tunnel T, and can be used to align the acquired three-dimensional shape data with the designed three-dimensional shape data.

[0082] [Inspection of Tunnel T] FIG. 15 is a flowchart illustrating the process of inspecting tunnel T using an inspection tool. As shown in FIG. 2 and FIG. 5(a), the inspection device 2 is mounted on a vehicle V (mobile body) capable of traveling within a tunnel T. The inspection of the inner circumference Ta of the tunnel T by the inspection tool 25 is performed for each inspection area, which is divided into a plurality of inspection areas in the longitudinal direction of the tunnel T. In this embodiment, the inspection is performed for each tunnel structure Tx.

[0083] First, the teaching point setting unit 712 sets an inspection range (inspection area) of the inner circumference Ta of the tunnel T by the inspection tool 25 (step S301). The inspection area is set based on the movable range of the arm portion 21 (see FIG. 1) that supports the inspection tool 25 and the arrangement of the inspection device 2 inside the tunnel T.

[0084] When the inspection range is set, the teaching point setting unit 712 sets a movement trajectory ML for moving the inspection tool along the inner periphery Ta of the inspection area (step S302). The movement trajectory ML set by the teaching point setting unit 712 is a movement trajectory for moving the inspection tool 25 along the inner circumference Ta of the tunnel T while keeping a predetermined gap between the inspection tool 25 and the inner circumference Ta of the tunnel T. The movement trajectory ML is set based on the design three-dimensional shape data of the inner circumference Ta of the tunnel T stored in the storage unit 72.

[0085] The movement trajectory ML is composed of a plurality of teaching points MP arranged on the movement trajectory ML. The teaching points MP are coordinates within the tunnel T on the movement trajectory ML, and are coordinate data indicating the movement destination of the inspection tool 25. Figure 5 (b) shows an example of a movement trajectory ML and a teaching point MP when the inspection tool 25 alternately moves from one side GDa of the inner circumference Ta of the tunnel T to the zenith and from the zenith to the other side GDb while shifting its position in the longitudinal direction of the tunnel T.

[0086] Once the movement trajectory ML is set, the teaching point correction unit 713 aligns the three-dimensional shape data generated by the three-dimensional shape data generation unit 717 (three-dimensional shape data: point cloud data indicating the actual shape of the inner circumference Ta of the tunnel T) with the designed three-dimensional shape data (step S303).

[0087] This alignment is performed based on a reference position CS on the floor surface GD. The three-dimensional shape data showing the actual shape of the inner circumference Ta of the tunnel T generated in the above-mentioned step 106 (see FIG. 9) is point cloud data in a coordinate system based on the reference position CS. The three-dimensional shape data generated based on the design data is also point cloud data in a coordinate system based on the reference position CS. Therefore, by aligning the two three-dimensional shape data based on the reference position CS, it is possible to calculate the deviation (error: Δx, Δy, Δz) in three-dimensional space (XYZ space) between the three-dimensional shape data (point cloud data) showing the actual shape of the inner circumference Ta of the tunnel T and the design three-dimensional shape data.

[0088] The teaching point correction unit 713 calculates an error between the three-dimensional shape data indicating the actual shape of the inner periphery Ta of the tunnel T and the design three-dimensional shape data (step S304). Then, the teaching point correcting unit 713 compares the three-dimensional shape data indicating the actual shape of the inner periphery Ta of the tunnel T with the movement trajectory ML to determine whether or not the movement trajectory ML needs to be corrected (step S305).

[0089] Specifically, the teaching point correction unit 713 plots teaching points MP included in the movement trajectory ML set from the design 3D shape data on the 3D shape data (point cloud data) indicating the actual shape of the inner circumference Ta of the tunnel T, taking into account the error calculated in step S305. Then, when the inspection tool 25 is moved according to the teaching points, it is confirmed whether or not there are any teaching points MP that would hinder the movement of the inspection tool 25.

[0090] The teaching point correction unit 713 determines that correction of the movement trajectory ML is necessary when there is a teaching point MP at which the inspection tool 25 may come into contact with the inner circumference Ta of the tunnel T, or when there is a teaching point MP at which the inspection tool 25 is too close to the inner circumference Ta of the tunnel T, causing an impediment to inspection by the inspection tool 25.

[0091] As an example, as shown in (c) of Figure 5, a teaching point where the distance between the teaching point Mp and the inner circumference Ta of the tunnel T identified by the three-dimensional shape data (point cloud data) in the normal direction of the inner circumference Ta is less than a predetermined threshold distance Tha is recognized as a teaching point MP that poses an obstacle to inspection by the inspection tool 25.

[0092] When it is determined that the movement trajectory ML needs to be corrected (Yes in step S305), the teaching point correcting unit 713 corrects the movement trajectory ML set by the teaching point setting unit 712 (step S306). Specifically, the teaching point correction unit 713 changes the coordinates in the space within the tunnel T of each teaching point MP that causes an obstacle to inspection by the inspection tool 25 to coordinates that do not cause an obstacle, and sets the teaching point identified by the changed coordinates as the corrected teaching point MP'.

[0093] As an example, the position of the teaching point is offset in the normal direction of the inner circumference Ta of the tunnel T specified by the three-dimensional shape data (point cloud data), and the position after the offset is set as the corrected teaching point MP'.

[0094] Then, a movement trajectory consisting of a plurality of teaching points including the corrected teaching point is reset as a movement trajectory ML (step S307).

[0095] The teaching point correction unit 713 outputs the corrected movement trajectory ML to the drive control unit 710. On the other hand, when it is determined that correction of the movement trajectory ML is not necessary (step S305, No), the teaching point correction unit 713 outputs the movement trajectory input from the teaching point setting unit 712 as it is to the drive control unit 710. In other words, the correction of the movement trajectory is not performed.

[0096] The drive control unit 710 performs drive control of the inspection tool 25 (step S308) and operates the arm unit 21 so that the inspection tool 25 passes through each teaching point MP on the movement trajectory ML input from the teaching point correction unit 713 in order. As a result, the inspection tool 25 moves along a movement trajectory ML consisting of a plurality of teaching points MP, while keeping a predetermined distance from the inner circumference Ta of the tunnel T.

[0097] When inspection of the inspection area for which the movement trajectory ML has been set by the inspection tool 25 is completed, if there is an inspection area that has not been inspected (step S309, Yes), the processing from step S203 to step S209 is repeated and inspection by the inspection tool 25 is performed. Then, when the inspection of all the inspection areas is completed (step S309, No), the inspection of the tunnel T by the inspection device 2 is terminated.

[0098] In this manner, the error between the three-dimensional shape data obtained by measuring the inner circumference Ta of the tunnel T (three-dimensional shape data: point cloud data showing the actual shape of the inner circumference Ta of the tunnel T) and the design three-dimensional shape data is calculated. Then, when moving the inspection tool 25 along the movement trajectory ML set from the design three-dimensional shape data, the teaching points MP that hinder the movement of the inspection tool 25 are corrected according to the calculated error. This allows the inspection tool 25 to be moved along the inner periphery Ta of the tunnel T to properly inspect the tunnel without being affected by differences between the actual shape of the inner periphery Ta of the tunnel T and the design shape specified by the design three-dimensional shape data.

[0099] As described above, the tunnel inspection system 1 according to this embodiment has a working device used to scan the tunnel T having a semi-cylindrical shape. (1) The working device is A laser tracker 3 (coordinate data acquisition device) that scans the inner circumference of a tunnel T (structure) and acquires coordinate data of a measurement point P; and a control device 7 that controls the scanning by the laser tracker 3. The control device 7 is a reference position determination unit 716 that determines a reference position CS within the tunnel T based on coordinate data of the characteristic shape of the inner circumference Ta of the tunnel T acquired by the laser tracker 3; The system also has a three-dimensional shape data generation unit 717 that generates three-dimensional shape data indicating the actual shape of the tunnel T based on a reference position CS using coordinate data of multiple measurement points P set on the inner circumference Ta of the tunnel T. The characteristic shape is located on a plane A perpendicular to a central axis CX along the longitudinal direction of the tunnel T, and is formed to have a range in the circumferential direction around the central axis CX.

[0100] With this configuration, the reference position CS can be determined using the characteristic shape of the inner circumference TA of the tunnel T without using target markers or reflectors, and three-dimensional shape data showing the actual shape of the tunnel T can be generated based on the reference position CS. This eliminates the labor and time that workers would have had to spend setting up target markers and replacing them with reflectors, making inspections inside tunnels easier.

[0101] (2) In (1) above, The tunnel T is configured by lining up cylindrical tunnel structures Tx (structures having an inner circumference with an arc-shaped cross section) in the longitudinal direction of the tunnel T. The characteristic shape is a boundary line Tj of a connection portion J between one tunnel structure Tx and another tunnel structure Tx.

[0102] The joints, which are the connections between the tunnel structures Tx, Tx, appear at regular intervals in the longitudinal direction of the tunnel T. Therefore, by using the characteristic shape provided at the joints to determine the reference position CS instead of the target marker or reflector, it is possible to save the labor and time of workers that was allocated to setting the target marker and replacing the target marker with a reflector. In particular, at the connection J between the tunnel structures Tx, Tx, a boundary line Tj appears visibly along the circumferential direction of the inner circumference Ta of the tunnel T. Therefore, by using the boundary line Tj as a characteristic shape, no construction work is required to provide a characteristic shape on the inner circumference Ta of the tunnel T. Therefore, by using the boundary line Tj to determine the reference position CS, it is possible to save time required for advance preparations before starting inspection of the tunnel T.

[0103] (3) In (2) above, At a connection J between the tunnel structures Tx, Tx, a recess 10 is provided whose distance from the inner periphery Ta of the tunnel T changes continuously in the longitudinal direction (direction of the central axis CX) of the tunnel T (see FIG. 6). In a cross-sectional view along the longitudinal direction of the tunnel T, the recess 10 has a deepest point Pd where the distance L10 from the inner circumference Ta of the tunnel T is maximum (see FIG. 7). The deepest points Pd are connected in a circumferential direction around the central axis CX to form a boundary line Tj.

[0104] With this configuration, the recess 10 can be used as a characteristic shape for determining the reference position CS. The laser tracker 3 is a device that measures the distance to an object. If a portion of the characteristic shape on the inner circumference Ta of the tunnel T does not have a large difference in shape from other portions around the characteristic shape, there may be a case where there is no large difference between the distance from the laser tracker 3 to the portion of the characteristic shape and the distance from the laser tracker 3 to the other portions. In such a case, it may not be possible to identify the distance to the portion with the characteristic shape from the measurement result of the distance to the measurement point P on the inner circumference Ta of the tunnel T. If a recess 10 whose distance from the inner circumference Ta of the tunnel T changes continuously in the direction of the central axis CX of the tunnel T is provided at the connection J of the tunnel structures Tx, Tx, the presence of the recess 10 can be reliably detected from the distance measurement results. Furthermore, if the deepest point Pd of the recess 10 is taken as the characteristic shape, the position of the deepest point Pd, which is the characteristic shape, and the distance to the deepest point Pd can be obtained with high accuracy by checking the change in the distance measurement results. Since the coordinate data of the boundary line Tj used to determine the reference position CS can be obtained with high accuracy, it is expected that the accuracy of the coordinate data of the determined reference position CS will be improved.

[0105] (4) In (3) above, The control device 7 is The scanning range setting unit 714 sets a scanning range consisting of multiple measurement points P in a range crossing the longitudinal direction of the tunnel T, the connection portion J between the tunnel structures Tx, Tx, and sets multiple scanning ranges by shifting their positions along the inner circumference Ta of the tunnel T. The reference position determining unit 716 identifies the deepest point Pd for each scanning range from the distance to each measurement point P included in the scanning range. The reference position determination unit 716 sets a virtual circle Im on the circumference of which the deepest point Pd identified for each scanning range is located, and determines the center of the virtual circle Im as the reference position CS.

[0106] For example, the deepest points Pd1 to Pd7 of each scanning range set at different height positions h1 to h7 on the inner circumference Ta of the tunnel T can be said to be located on the outer periphery of a virtual circle Im (see Figure 8) whose outer periphery is the inner circumference Ta of the cylindrical tunnel structure Tx. Assuming that each of the deepest points Pd1 to Pd7 is located on the outer periphery of the imaginary circle Im, the coordinates of the center C of the imaginary circle Im are calculated, and the calculated coordinates of the center C of the imaginary circle Im become the coordinates of the center in the cross section of the tunnel structure Tx. As a result, the position of the center C in the longitudinal direction (Y direction) of the tunnel T and the position in the width direction (X direction) of the tunnel T become clear reference positions.

[0107] (5) In (4) above, The scanning range setting unit 714 sets a plurality of measurement points P at intervals in the circumferential direction around the central axis CX and in the direction of the central axis CX to set a shape measurement range. The three-dimensional shape data generation unit 717 generates coordinate data for each measurement point P based on the reference position CS from the distance to each measurement point P included in the shape measurement range, and generates three-dimensional shape data indicating the actual shape of the tunnel T from the generated coordinate data of each measurement point P.

[0108] The three-dimensional shape data (three-dimensional shape data according to the conventional example) generated by scanning the inner circumference Ta of the tunnel T with a 3D scanner has a large total number of point cloud data constituting the three-dimensional shape data, and a large data volume. The three-dimensional shape data generated by scanning with the laser tracker 3 (the three-dimensional shape data of the present application) has a smaller amount of data than when a 3D scanner is used. In particular, as shown in Figure 12, by adjusting the circumferential spacing Ds around the central axis CX of the measurement points P included in the shape measurement range and the spacing Dy in the direction of the central axis CX (Y direction), the total amount of point cloud data included in the 3D shape data can be reduced to the minimum amount required for comparison with 3D shape data created based on CAD data. This reduces the processing load when generating 3D shape data that shows the actual shape of tunnel T and comparing it with 3D shape data created based on CAD data. In addition, the processing time can be shortened by the amount of data volume reduced, which is expected to improve work efficiency.

[0109] (6) In (5) above, The reference position determination unit 716 A virtual cylinder is created with each measurement point P arranged on its outer circumference, and the center of the tunnel structure and the inclination of the tunnel structure are calculated from the radius and axial direction of the virtual cylinder, and reflected in the three-dimensional shape data.

[0110] With this configuration, the three-dimensional shape data is generated taking into account the inclination of the tunnel structure Tx, so that the positional accuracy of the reference position CS is improved. Furthermore, the accuracy of comparison between three-dimensional shape data based on the reference position is also improved.

[0111] (7) In any one of the above (1) to (6), It has an inspection tool 25 arranged to face the inner circumference Ta of the tunnel T, and a support mechanism 20 for the inspection tool 25. The laser tracker 3 (coordinate data acquisition device) and the support mechanism 20 for the inspection tool 25 are mounted on a lift table 50 (lift table) on the vehicle V side via a common first support base 52. The first support base 52 is movable in the front-rear direction of the vehicle V. The support mechanism 20 of the inspection tool 25 is mounted on a second support base 55 which is movable in the width direction of the vehicle V on the first support base 52.

[0112] In the conventional example, the support mechanism 20 of the inspection tool 25 is mounted on the vehicle, while the laser tracker 3 is located away from the vehicle V. Therefore, the relative positional relationship between the inspection tool 25 and the laser tracker 3 is not always the same. In the conventional example, it is necessary to install a reflector on the inspection tool 25 and measure the relative positional relationship between the inspection tool 25 and the laser tracker 3 in advance. As described above, the laser tracker 3 and the support mechanism 20 for the inspection tool 25 are mounted on the lift table 50 (lift table) on the vehicle V side via the common first support base 52, so the positional relationship between the laser tracker 3 and the inspection tool 25 can be identified without performing measurements using a reflector. Furthermore, the support mechanism 20 of the inspection tool 25 is mounted on a second support platform 55 that is movable in the width direction of the vehicle V on the first support platform 52, and a change in the relative positional relationship between the first support platform 52 and the second support platform 55 can be identified from the drive amount of a drive motor (servo motor) not shown that displaces the second support platform 55. Therefore, the relative positional relationship in the X direction between the laser tracker 3 and the inspection device 2 can always be identified from the drive amount of the drive motor (servo motor). Even if the relative positional relationship between the laser tracker 3 and the support mechanism 20 of the inspection tool 25 changes, the positional relationship between the laser tracker 3 and the inspection tool 25 can be identified without performing measurement using a reflector.

[0113] (I) When viewed from the direction of the central axis CX of the tunnel T, the intersection point between a straight line that is perpendicular to the floor surface GD of the tunnel T and intersects the central axis CX and the floor surface GD is determined as the reference position.

[0114] The coordinate data of each of the deepest points Pd1 to Pd7 is coordinate data (coordinate data of the sensor coordinate system) based on the position of the laser tracker 3. Because the laser tracker 3 is mounted on the vehicle V, the height of the laser tracker 3 from the floor surface GD can be identified. The installation height is subtracted from the Z component of the coordinate data of the center C based on the position of the laser tracker 3. As a result, the obtained coordinate data becomes the coordinate data of the reference position CS' (center position) of the floor surface GD inside the tunnel T. This reference position CS' is located at the center in the width direction of the floor surface GD, and is located on the same plane as the boundary line Tj of the tunnel structure Tx. As a result, the reference position CS' is a reference position in which the position in the longitudinal direction (Y direction) of the tunnel T and the position in the width direction (X direction) of the tunnel T are clear.

[0115] (II) In any one of (1) to (7) and (I) above, The control device 7 is A teaching point setting unit 712 that sets the coordinates of the destination of the inspection tool 25 in the tunnel T as a teaching point based on the three-dimensional shape data of the design of the tunnel T; and a teaching point correction unit 713 that corrects teaching points based on an error between the three-dimensional shape data of the design of the tunnel T and the three-dimensional shape data showing the actual shape of the tunnel. The teaching point correction unit 713 is Using the reference position CS as a reference, coordinate matching is performed between the three-dimensional design shape data of the tunnel T and the three-dimensional shape data showing the actual shape of the tunnel T, and the error is calculated.

[0116] With this configuration, by using the determined reference position CS as a reference, it is possible to perform coordinate alignment between the three-dimensional shape data showing the actual shape of the tunnel T and the three-dimensional shape data of the design of the tunnel T with high positional accuracy. By aligning the coordinates with the reference position CS as the reference, the three-dimensional shape data showing the actual shape of the tunnel T and the three-dimensional shape data in the design of the tunnel T can be handled in the same coordinate system. Therefore, the movement trajectory ML of the inspection tool 25 created based on the three-dimensional shape data in the design of the tunnel T can be plotted in the coordinate system of the three-dimensional shape data indicative of the actual shape of the tunnel T, and it can be determined whether or not there is an obstacle to the movement of the inspection tool 25 along the movement trajectory ML. As a result, if there is an impediment to the movement of the inspection tool 25 along the movement trajectory ML, the movement trajectory can be corrected, and a situation in which the movement of the inspection tool 25 along the movement trajectory ML is impeded can be suitably prevented.

[0117] (III) In any one of (1) to (7) and (I) and (II) above, The teaching point setting unit 712 sets a teaching point MP indicating the destination of the inspection tool 25 at a position inside the tunnel T, away from the inner circumference Ta of the tunnel T specified by the design three-dimensional shape data, in the normal direction of the inner circumference Ta, a predetermined threshold distance Tha or more. The teaching point correction unit 713 recognizes a teaching point MP where the distance between the teaching point Mp and the inner circumference Ta is less than a predetermined threshold distance Tha as a teaching point MP that will hinder inspection by the inspection tool 25. The teaching point correction unit 713 offsets the teaching point MP that is hindering inspection by the inspection tool 25 in the normal direction of the inner circumference Ta of the tunnel T identified by the three-dimensional shape data (point cloud data), and sets the position after the offset as the corrected teaching point MP'.

[0118] With this configuration, if there is an impediment to the movement of the inspection tool 25 along the movement trajectory ML, the movement trajectory can be corrected, and the situation in which the movement of the inspection tool 25 along the movement trajectory ML is impeded can be preferably prevented.

[0119] In the above-described embodiment, the boundary line Tj appearing at the connection portion J between the tunnel structures Tx and Tx has a characteristic shape. The boundary line Tj is a straight line connecting the deepest points Pd of the recess 10 in the circumferential direction around the central axis CX. The characteristic shape may be any part having a shape in which the distance from the inner circumference Ta of the tunnel T changes continuously in the scanning direction by the laser tracker 3, increasing and decreasing the distance from the laser tracker 3. Therefore, it may be a linear protrusion that protrudes from the inner circumference Ta of the tunnel T and has a predetermined length range in the circumferential direction around the central axis CX.

[0120] In the above embodiment, a tunnel is given as an example of a structure having a semi-cylindrical shape, but the "structure having a semi-cylindrical shape" in the present invention is not limited to only a tunnel. For example, the present invention may be applied to a semi-cylindrical soundproof and disaster prevention hood that covers a road or a railway from above for the purpose of soundproofing and disaster prevention, or to a structure such as a bridge having a so-called arched structure. In the case of a semi-cylindrical soundproof disaster prevention hood, the arch-shaped frame portion and the connection portions between the soundproof disaster prevention hoods are used as characteristic shapes to achieve the same effects as those of the above-described embodiment.

[0121] In the embodiment described above, an example has been given in which, when measuring the shape of the tunnel T, the scanning range setting unit 714 sets a measurement point sequence PL in which a plurality of measurement points P are arranged at a predetermined interval Dy in the longitudinal direction (Y direction) of the tunnel T, and also sets a plurality of measurement point sequences PL at a predetermined interval Ds in the circumferential direction of the inner circumference Ta of the tunnel T. The measurement points P do not necessarily need to be set at the predetermined intervals Dy and Ds in the longitudinal direction of the tunnel T and the circumferential direction of the inner circumference Ta of the tunnel T, respectively. Ultimately, the measurement points P may be set at different intervals as long as the number of measurement results required to determine the virtual cylinder can be obtained from the measurement results of the distance to each measurement point P.

[0122] In the embodiment described above, the case where the three-dimensional shape data of the tunnel is generated in the following order is exemplified. (a) Determining a reference position for measurement using a virtual circle (step S101); (b) Setting a scanning range for shape measurement and generating 3D shape data by scanning the scanning range (steps S102 to S104); (c) Generating 3D shape data of the tunnel based on the reference position (step S105). The 3D shape data of the tunnel may be generated in the following order: (a') Setting the scanning range for shape measurement and generating 3D shape data by scanning the scanning range; (b') Determining the reference position using a virtual circle; (c') Generating 3D shape data of the tunnel based on the reference position from the 3D shape data generated in (a') above. By doing so, the same effects as those in the above-described embodiment can be achieved.

[0123] The present invention can also be specified as a method for generating three-dimensional shape data. in particular, (IV) The method for generating three-dimensional shape data is a method for generating three-dimensional shape data for the inner circumference Ta of a tunnel T (a structure having a semi-cylindrical shape) which is formed by connecting tunnel structures (structures having an inner circumference with an arc-shaped cross section) in the longitudinal direction. The method for generating three-dimensional shape data includes the following steps. (a) A step of disposing the laser tracker 3 within the tunnel T so that its position in the longitudinal direction (Y direction) of the tunnel T is aligned with the boundary line Tj, which is the connection J between the tunnel structures Tx. (b) A step of setting a scanning range consisting of multiple measurement points P1 to P28 in an area crossing the boundary line Tj in the longitudinal direction (Y direction) of the tunnel T, and setting multiple scanning ranges by shifting their positions along the inner circumference of the tunnel T (Figure 10, step S201). (c) A step of identifying the deepest point Pd for each scanning range from the distance to each measurement point P included in the scanning range, and determining the center of a virtual circle Im on whose circumference the deepest point Pd identified for each scanning range is located as a reference position CS (FIG. 10, steps S202 to S208). (d) A step of setting a plurality of measurement points at intervals in the circumferential direction around the central axis of the tunnel structure Tx and in the central axis direction to set a shape measurement range (FIG. 9, step S102). (e) A step of generating coordinate data of each measurement point based on a reference position CS from the distance to each measurement point included in the shape measurement range, and generating actual three-dimensional shape data of the tunnel from the generated coordinate data of each measurement point (FIG. 10, steps S103 to S105).

[0124] With this configuration, it is possible to determine the reference position CS using the characteristic shape of the inner circumference Ta of the tunnel T without using a target marker or reflector, and to generate three-dimensional shape data showing the actual shape of the tunnel T based on the reference position CS. This eliminates the labor and time that workers would have had to spend setting up target markers and replacing them with reflectors, making inspections inside tunnels easier.

[0125] The present invention can also be specified as a program for generating three-dimensional shape data. in particular, (V) The program for generating three-dimensional shape data is a program for generating three-dimensional shape data for the inner circumference Ta of a tunnel T (a structure having a semi-cylindrical shape) which is composed of tunnel structures (structures having an inner circumference with an arc-shaped cross section) connected in the longitudinal direction. The program for generating three-dimensional shape data causes the computer to function as the following means. The laser tracker 3 is arranged in the tunnel T so that the position of the boundary line Tj, which is the connection part J between the tunnel structures Tx, and the position of the longitudinal direction (Y direction) of the tunnel T are aligned. (f) A means for setting a scanning range consisting of multiple measurement points P1 to P28 in an area crossing the boundary line Tj in the longitudinal direction (Y direction) of the tunnel T, and for setting multiple scanning ranges by shifting their positions along the inner circumference of the tunnel T (Figure 10, step S201). (g) A means for identifying the deepest point Pd for each scanning range from the distance to each measurement point P included in the scanning range, and determining the center of a virtual circle Im on whose circumference the deepest point Pd identified for each scanning range is located as a reference position CS (FIG. 10, steps S202 to S208). (h) A means for setting a shape measurement range by setting a plurality of measurement points at intervals in the circumferential direction around the central axis of the tunnel structure Tx and in the central axis direction (FIG. 9, step S102) (i) A means for generating coordinate data of each measurement point based on a reference position CS from the distance to each measurement point included in the shape measurement range, and generating actual three-dimensional shape data of the tunnel from the generated coordinate data of each measurement point (Figure 10, steps S103 to S105).

[0126] Even with this configuration, it is possible to determine the reference position CS using the characteristic shape of the inner circumference Ta of the tunnel T without using a target marker or reflector, and to generate three-dimensional shape data showing the actual shape of the tunnel T based on the reference position CS. This eliminates the labor and time that workers would have had to spend setting up target markers and replacing them with reflectors, making inspections inside tunnels easier.

[0127] The present invention is not limited to the above-described embodiment, and can be modified or altered as appropriate within the scope of the technical concept of the invention. [Explanation of symbols]

[0128] 1 Tunnel Inspection System 10 Floor structure 2 Inspection equipment 20 Support mechanism 21 Arm section 23 Actuator 24 Communication Interface (Communication IF) 25 Inspection Tools 3 Laser tracker (distance measuring device) 31 Irradiation unit 32 Light receiving part 33 Actuator 34 Communication Interface (Communication IF) 35 Storage section 36 Control Unit 37 Bus 5 Lifting mechanism 50 Lift table (lifting platform) 51 Guide rail 52 1st support stand 53 Foundation 54 Guide rail 55 Second support stand 7 Control device 71 Processing section 711 Drive control unit 712 Teaching point setting section 713 Teaching point correction section 714 Scanning range setting unit 715 Scanning control section 716 Reference position setting section 717 3D Shape Data Generation Unit 72 Memory section 73 Input / Output Ports 74 Communication Interface (Communication IF) 75 Bus 76 Input Devices 77 Output Device C center line GD Floor surface GDa one side GDb other side T-Tunnel Ta Inner circumference Tj border P measurement point Pd deepest point V Vehicle (moving object)

Claims

1. A working device used to scan a structure having a semi-cylindrical shape, comprising: a coordinate data acquisition device that scans the inner periphery of the structure and acquires coordinate data of measurement points; A control device for controlling scanning by the coordinate data acquisition device, The control device includes: a reference position determination unit that determines a reference position within the structure based on the coordinate data of the characteristic shape of the inner periphery of the structure acquired by the coordinate data acquisition device; a three-dimensional shape data generating unit that generates actual three-dimensional shape data of the structure based on the reference position using coordinate data of a plurality of measurement points set on an inner periphery of the structure, A working device, wherein the characteristic shape is located on a plane perpendicular to a central axis along the longitudinal direction of the structure, and is formed to have a range in the circumferential direction around the central axis.

2. In claim 1, The structure is configured by arranging structures each having an inner circumference with an arc-shaped cross section in a longitudinal direction of the structure, A working device, wherein the characteristic shape is a boundary line of a connection portion between the structure and another structure.

3. In claim 2, the connecting portion is provided with a recess whose distance from an inner periphery of the structure changes continuously in a longitudinal direction of the structure, a working device, in which, when viewed in a cross-sectional view along the longitudinal direction of the structure, the recess has a deepest point where the distance from the inner circumference of the structure is the greatest, and the deepest points are connected in a circumferential direction around the central axis to form the boundary line.

4. In claim 3, The control device includes: a scanning range setting unit that sets a scanning range consisting of a plurality of measurement points in a range that crosses the connection portion in the longitudinal direction of the structure, and sets a plurality of scanning ranges by shifting positions along an inner periphery of the structure, The reference position determination unit is A working device that identifies the deepest point for each scanning range from the distance to each measurement point included in the scanning range, and determines as the reference position the center of a virtual circle on whose circumference the deepest point identified for each scanning range is located.

5. In claim 4, the scanning range setting unit sets a plurality of measurement points spaced apart in a circumferential direction around the central axis and in a direction of the central axis to set a shape measurement range; The three-dimensional shape data generation unit generates coordinate data for each measurement point based on the reference position from the distance to each measurement point included in the shape measurement range, and generates actual three-dimensional shape data of the structure from the generated coordinate data for each measurement point.

6. In claim 5, The three-dimensional shape data generation unit A working device that creates a virtual cylinder with each of the measurement points arranged on its outer periphery, calculates the center of the structure and the inclination of the structure from the radius and axial direction of the created virtual cylinder, and reflects this in the three-dimensional shape data.

7. In any one of claims 1 to 6, An inspection tool disposed opposite an inner periphery of the structure, and a support mechanism for the inspection tool, The support mechanism for the coordinate data acquisition device and the inspection tool is mounted on a lift platform of a vehicle via a common first support platform, The first support base is movable in a front-rear direction of the vehicle, A working device, wherein the support mechanism of the inspection tool is movable in the width direction of the vehicle on the first support base.

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