Conduit line position surveying device and conduit line position surveying method

Abstract

To more accurately survey the position of a conduit line.SOLUTION: A conduit line position surveying device is provided which comprises: a movable body that moves inside a pipe; a distance measuring instrument that measures the distance of movement of the movable body; a distance sensor that is mounted on the movable body, emits light to the inner face of the pipe located in a direction opposite to the direction of movement of the movable body, receives the light reflected on the inner face, and calculates the distance to the inner face on the basis of the time from the light emission to the light reception; a posture measuring instrument that measures the posture of the distance sensor; and a computer that generates survey data indicating calculated values of the distance to the inner face obtained by the distance sensor, and measured values of the posture obtained by the posture measuring instrument, in association with a plurality of measured values of the distance of movement obtained by the distance measuring instrument.SELECTED DRAWING: Figure 1A

Description

[Technical field]

[0001] The present disclosure relates to a pipeline location detection device and a pipeline location detection method. [Background technology]

[0002] Communication cables or power lines run underground inside pipes. Such pipes are often buried underground or shielded, making them difficult or impossible to see. However, even in such cases, it may be necessary to explore how the pipes are arranged three-dimensionally. There are several methods known for this exploration.

[0003] As described in Patent Document 1, a method is known in which multiple rings are arranged in the extension direction of a pipe, a pipeline position detection device is moved inside the pipe while emitting light, and the reflected light from the multiple rings is photographed by a camera, and the position of the pipeline is detected from the obtained image. In this method, when detecting the cross section of the pipe, each ring needs to be positioned at the center of the pipe. Therefore, a configuration is adopted in which multiple springs are attached to each ring at equal intervals in the circumferential direction of the ring, and the springs are placed against the inner surface of the pipe, and the elastic force of the springs floats each ring at the center of the pipe. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-012646 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the method of Patent Document 1, it can be difficult to position a large number of springs at equal intervals, and since the elasticity of a large number of springs is not necessarily uniform, each ring will not be positioned in the center of the pipe, which may affect the accuracy of detecting the position of the pipe.

[0006] In view of the above circumstances, an object of the present disclosure is to detect the position of a pipeline more accurately. [Means for solving the problem]

[0007] A pipeline location detection device according to one embodiment includes: A moving body that moves inside the tube; a distance measuring device that measures a moving distance of the moving object; a distance sensor mounted on the moving body, emitting light toward an inner surface of the tube located in a direction opposite to the moving direction of the moving body, receiving the light reflected by the inner surface, and calculating a distance to the inner surface based on a time from light emission to light reception; an attitude measuring device that measures an attitude of the distance sensor; a computer that generates search data indicating each calculated value of the distance to the inner surface obtained by the distance sensor and each measured value of the attitude obtained by the attitude measuring device, in association with each of a plurality of measured values ​​of the movement distance obtained by the distance measuring device; Equipped with.

[0008] A pipeline location detection method according to an embodiment includes the steps of: measuring a moving distance of the moving body by a distance measuring device while moving the moving body inside the pipe; a distance sensor mounted on the movable body, which emits light toward an inner surface of the pipe located in a direction opposite to the moving direction of the movable body, and receives the light reflected by the inner surface, calculates a distance to the inner surface based on a time from light emission to light reception by the distance sensor while the movable body is moved inside the pipe; measuring the attitude of the distance sensor by an attitude measuring device while moving the moving body inside the pipe; acquiring, by a computer, calculated values ​​of the distance to the inner surface obtained by the distance sensor and measured values ​​of the attitude obtained by the attitude measuring device, the calculated values ​​corresponding to a plurality of measured values ​​of the movement distance obtained by the distance measuring device, the measured values ​​differing from each other by a certain value; correcting, by the computer, the calculated value of the distance to the inner surface obtained for each of the plurality of measured values ​​of the moving distance based on the measured value of the attitude obtained, to obtain a corrected value of the distance to the inner surface; Identifying, by the computer, a pipeline position of the pipe for each of the plurality of measurements of the travel distance using a correction value of the distance to the inner surface obtained; Includes. Effect of the Invention

[0009] According to the present disclosure, the position of a pipeline can be detected more accurately. [Brief description of the drawings]

[0010] [Figure 1A] 1 is a perspective view showing a first embodiment of a pipeline location detecting device in a state where it is disposed inside a pipe. [Figure 1B] 1B is a front view showing the pipeline location detecting device shown in FIG. 1A. [Diagram 2] 1 is a flowchart showing the operation of an embodiment of a pipeline location detection method. [Figure 3A] 1B is a perspective view showing the pipeline position detection device shown in FIG. 1A in a state where the optical axis of light received by the optical receiver is tilted upward. [Figure 3B] FIG. 3A is a diagram showing the distance sensor as a reference. [Figure 3C] FIG. 13 is a diagram showing a distance sensor and corrected three-dimensional data. [Figure 4A] FIG. 1 is a perspective view showing a simplified representation of visualization information generated by a computer. [Figure 4B] FIG. 4C is a front view showing the visualized information of FIG. 4B. [Figure 5A] 1 is a diagram showing three-dimensional correction data acquired by a distance sensor along the moving direction of a moving body. [Figure 5B] FIG. 5B is a front view showing the three-dimensional correction data and the center position of FIG. 5A. [Figure 5C]5C is a diagram showing the center position of FIG. 5B, as viewed from a direction perpendicular to the moving direction of the moving body. [Figure 6] FIG. 13 is a diagram showing superimposed center positions along the moving direction of the moving body. [Figure 7A] FIG. 11 is a perspective view showing a second embodiment of a pipeline location detecting device in a state where it is disposed inside a pipe. [Figure 7B] FIG. 7B is a front view showing the distance sensor shown in FIG. 7A. [Figure 7C] FIG. 7B is a side view showing the distance sensor shown in FIG. 7A. [Figure 8A] 13 is a diagram showing changes over time in the amplitude of reflected light and the amplitude of light received by a light receiver when the distance sensor does not include a light collector. FIG. [Figure 8B] 13 is a diagram showing changes over time in the amplitude of reflected light and the amplitude of light received by a light receiver when the distance sensor is equipped with a light collector. FIG. [Figure 9A] FIG. 11 is a perspective view showing a third embodiment of a pipeline location detecting device in a state where it is disposed inside a pipe. [Figure 9B] FIG. 9B is a front view showing the distance sensor shown in FIG. 9A. [Figure 9C] FIG. 9B is a side view showing the distance sensor shown in FIG. 9A. [Figure 10A] FIG. 11 is a perspective view showing a fourth embodiment of a pipeline location detecting device in a state where it is disposed inside a pipe. [Figure 10B] FIG. 10B is a front view showing the distance sensor shown in FIG. 10A. [Figure 10C] FIG. 10B is a side view showing the distance sensor shown in FIG. 10A. [Figure 11A] FIG. 11 is a perspective view showing a fifth embodiment of a pipeline location detecting device in a state where it is disposed inside a pipe. [Figure 11B] FIG. 11B is a front view showing the distance sensor shown in FIG. 11A. [Figure 11C] FIG. 11B is a side view showing the distance sensor shown in FIG. 11A. [Figure 12A] FIG. 13 is a perspective view of a sixth embodiment of a pipeline location detecting device, as viewed from above, showing the device placed inside a pipe. [Figure 12B]FIG. 12B is a front view showing the distance sensor shown in FIG. 12A. [Figure 12C] FIG. 12B is a side view showing the distance sensor shown in FIG. 12A. [Figure 13A] FIG. 13 is a side view showing information acquired by a computer. [Figure 13B] FIG. 13B is a cross-sectional view taken along line PP in FIG. 13A. [Figure 14A] FIG. 13 is a perspective view showing a seventh embodiment of a pipeline location detecting device in a state where it is disposed inside a pipe. [Figure 14B] FIG. 14B is a front view showing the distance sensor shown in FIG. 14A. [Figure 14C] FIG. 14B is a side view showing the distance sensor shown in FIG. 14A. [Figure 15A] FIG. 11 is a plan view showing information acquired by a computer. [Figure 15B] FIG. 15B is a cross-sectional view taken along line PP in FIG. 15A. [Figure 16A] FIG. 13 is a perspective view showing an eighth embodiment of a pipeline location detecting device in a state where it is disposed inside a pipe. [Figure 16B] FIG. 16B is a front view showing the distance sensor shown in FIG. 16A. [Figure 16C] FIG. 16B is a side view showing the distance sensor shown in FIG. 16A. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] [First embodiment] The first embodiment will be described below with reference to the drawings.

[0012] In each drawing, the same or corresponding parts are denoted by the same reference numerals. In the description of this embodiment, the description of the same or corresponding parts will be omitted or simplified as appropriate.

[0013] The configuration of a pipeline location detection device 100 according to this embodiment will be described with reference to Fig. 1A. The pipeline location detection device 100 detects the location of a pipeline (pipe 1000).

[0014] The pipe 1000 is a pipe through which a communication cable or a power line may pass. Such a pipe 1000 is buried, for example, under a road. The diameter of the pipe 1000 is 1 m or less, and a small one is 100 mm or less (for example, 50 mm). The diameter of the pipe 1000 may vary in the axial direction due to dimensional errors. Furthermore, the pipe 1000 may be bent when it is placed. At this time, unevenness may occur in the pipe 1000. Furthermore, after the pipe 1000 is buried, the position of the pipeline or the pipe shape may change due to the surrounding earth pressure.

[0015] The pipeline location detection device 100 includes a moving body 10, a distance measurement device 20, a distance sensor 30, an attitude measurement device 40, and a computer 50. The pipeline location detection device 100 may further include a battery 60.

[0016] The moving body 10 moves inside the pipe 1000. The moving body 10 may be towed by a towing rope 200. The moving body 10 may be towed in a moving direction d from the exit of the pipe 1000 toward the entrance. The towing rope 200 may be towed by an operator or a motor. In another example, the moving body 10 may be self-propelled. The moving body 10 may be a platform on which a distance measuring device 20, a distance sensor 30, an attitude measuring device 40, a computer 50, and a battery 60 are mounted.

[0017] The distance measuring device 20 measures the distance traveled by the moving body 10. The distance measuring device 20 may be an encoder. The distance measuring device 20 has a rotating part 21 that contacts the inner surface 1000i of the pipe 1000. When the moving body 10 moves in the extension direction of the pipe 1000 by the towing rope 200, the rotating part 21 that contacts the inner surface 1000i of the pipe 1000 rotates around the rotation axis, and the amount of rotation is converted into the distance traveled by the moving body 10. The distance measuring device 20 may issue a trigger signal every time the distance traveled increases by a predetermined value.

[0018] The distance sensor 30 is mounted on the moving body 10. The distance sensor 30 emits light to an inner surface 1000i of the tube 1000, which is located in the opposite direction to the moving direction d of the moving body 10. The distance sensor 30 receives the light reflected by the inner surface 1000i. The distance sensor 30 calculates the distance to the inner surface 1000i based on the time from light emission to light reception. The distance sensor 30 measures not only one point but multiple points simultaneously. The distance sensor 30 may be, for example, a TOF (Time-of-Flight) camera. The distance sensor 30 measures the distances of multiple points in a range with an angle of view of about 90° up, down, left, and right in an extremely short time to obtain three-dimensional distance data. The distance sensor 30 obtains data in a predetermined range in the extension direction of the tube 1000 (for example, a range of 0.3 m to 3.0 m forward from the front end of the distance sensor 30 when the outlet direction of the tube 1000 is the forward direction and the inlet direction is the rearward direction) in one measurement. The distance sensor 30 has a light emitter 31 and a light receiver 32. The distance sensor 30 may be a camera that measures the time it takes for light to be emitted from the light emitter 31, reflected by the inner surface 1000i of the tube 1000, and returned to the light receiver 32, and calculates the distance to each point (light reflection point) on the inner surface 1000i based on the measured time and the speed of light.

[0019] A plurality of light emitters 31 may be provided on the front surface of the distance sensor 30 (e.g., the surface facing the outlet of the tube 1000). As shown in FIG. 1B, four light emitters 31 are arranged in this embodiment. These light emitters 31 are turned on simultaneously to emit light. The optical axes of the light emitted from the four light emitters 31 are parallel. The light emitted from the light emitters 31 is, but is not limited to, near-infrared light, for example. The wavelength of the near-infrared light emitted from the light emitters 31 is, for example, 800 nm to 1000 nm. The light emitters 31 may be an LED (light emitting diode) or a laser.

[0020] The light receiver 32 is provided in a location surrounded by a plurality of light emitters 31 on the front surface of the distance sensor 30. The light receiver 32 receives light emitted from the light emitters 31 and reflected by the inner surface 1000i of the tube 1000. The light receiver 32 has, for example, about 50,000 to 300,000 light receiving elements (imaging elements) arranged therein (for example, 600 horizontal × 400 vertical). The light emitters 31 and the light receiver 32 may be arranged so that their central axes are parallel to each other.

[0021] The attitude measuring instrument 40 measures the attitude of the distance sensor 30. The attitude measuring instrument 40 may be fixed to the distance sensor 30. The attitude measuring instrument 40 may be an IMU (Inertial Measurement Unit). The attitude measuring instrument 40 can obtain the direction of gravity and three angles (roll angle, pitch angle, yaw angle) of the attitude measuring instrument 40 relative to gravity. The attitude measuring instrument 40 is mounted on the moving body 10. The attitude measuring instrument 40 can measure the inclination of the optical axis of light received by the light receiver 32 of the distance sensor 30 relative to the direction of gravity in three axial directions.

[0022] The computer 50 generates exploration data indicating each calculated value of the distance to the inner surface 1000i obtained by the distance sensor 30 and each measured value of the attitude obtained by the attitude measuring instrument 40, corresponding to each of the multiple measured values ​​of the travel distance obtained by the distance measuring instrument 20.

[0023] The computer 50 corrects the calculated value of the distance to the inner surface 1000i indicated in the probe data for each of the multiple measured values ​​of the travel distance based on the measured value of the attitude indicated in the probe data to obtain a corrected value of the distance to the inner surface 1000i. The computer that generates the probe data and the computer that obtains the corrected value of the distance to the inner surface 1000i may be separate computers. In such a configuration, the probe data is input from the former computer to the latter computer.

[0024] The computer 50 is a computer for processing three-dimensional data. The computer for processing three-dimensional data is used to specify the position of a pipeline as described below. Software for executing a method for detecting the position of a pipeline, which will be described later, is installed in the computer for processing three-dimensional data.

[0025] The computer 50 may function as a storage device that stores the data acquired by the distance measurement device 20, the distance sensor 30, and the attitude measurement device 40, respectively.

[0026] The computer 50 may be capable of communicating with the distance measuring device 20, the distance sensor 30, and the attitude measuring device 40 via a network. The network includes, for example, the Internet, at least one WAN, at least one MAN, or any combination thereof. "WAN" is an abbreviation for wide area network. "MAN" is an abbreviation for metropolitan area network. The network may include at least one wireless network, at least one optical network, or any combination thereof. The wireless network is, for example, an ad-hoc network, a cellular network, a wireless LAN, a satellite communication network, or a terrestrial microwave network. "LAN" is an abbreviation for local area network.

[0027] Computer 50 may be a general-purpose or special-purpose computer, such as a PC. "PC" is an abbreviation for personal computer.

[0028] The computer 50 temporarily stores in the main storage device, for example, a program stored in a portable medium or a program transferred from a server. The computer 50 then reads the program stored in the main storage device with a processor, and executes processing according to the read program with the processor. The computer 50 may read the program directly from the portable medium and execute processing according to the program. The computer 50 may execute processing according to the received program each time a program is transferred from the server to the computer 50. Processing may be executed by a so-called ASP-type service that realizes functions only by execution instructions and result acquisition without transferring a program from the server to the computer 50. "ASP" is an abbreviation for application service provider. A program is information used for processing by an electronic computer, and includes those equivalent to a program. For example, data that is not a direct command to the computer 50 but has a nature that specifies the processing of the computer 50 corresponds to "those equivalent to a program."

[0029] A part or all of the functions of the computer 50 may be realized by a programmable circuit or a dedicated circuit, that is, a part or all of the functions of the computer 50 may be realized by hardware.

[0030] The battery 60 supplies power to the distance measurement device 20 , the distance sensor 30 , the attitude measurement device 40 and the computer 50 .

[0031] The operation of the computer 50 according to the present embodiment will be described with reference to Fig. 2. The operation described below corresponds to the pipeline location exploration method according to the present embodiment. That is, the pipeline location exploration method according to the present disclosure includes, for example, steps S1 to S6 shown in Fig. 2.

[0032] Before the computer 50 performs S1, the operator prepares the pipe position detection device 100 outside the open end of the pipe 1000 on the measurement start side (e.g., the end on the outlet side). Then, the operator sends the towing rope 200 from the open end of the pipe 1000 on the measurement start side to the open end of the pipe 1000 on the measurement end side (e.g., the end on the inlet side) by a known method. This results in a state in which the pipe position detection device 100 is placed outside the open end of the pipe 1000 on the measurement start side, and the tip of the towing rope 200 is placed outside the open end of the pipe 1000 on the measurement end side. The operator puts the pipe position detection device 100 into the pipe 1000 from the open end on the measurement start side so that the front of the pipe position detection device 100, i.e., the side to which the light emitter 31 of the distance sensor 30 is fixed, faces the open end of the pipe 1000 on the measurement start side.

[0033] In S1, while the moving body 10 moves inside the pipe 1000, the distance measuring device 20 measures the distance traveled by the moving body 10. Specifically, the operator moves the pipeline location detection device 100 from the open end of the pipe 1000 on the measurement start side to the open end of the pipe 1000 on the measurement end side by pulling the towing rope 200 from the outside of the open end of the pipe 1000 on the measurement end side at as constant a speed as possible. If the side where the distance sensor 30 is located is the front, the pipeline location detection device 100 is pulled in the moving direction d (backward) shown in FIG. 1A.

[0034] While the pipeline location detection device 100 is moving, the distance measurement device 20 measures the distance traveled. Then, the distance measurement device 20 issues a trigger signal at every predetermined equal distance traveled. For example, the trigger signal is issued every time the pipeline location detection device 100 moves 10 cm. Every time a trigger signal is issued, the distance sensor 30 acquires 3D data and the attitude measurement device 40 measures at the same time.

[0035] In S2, while the moving object 10 moves inside the pipe 1000, the distance sensor 30 mounted on the moving object 10 calculates the distance to the inner surface 1000i based on the time from light emission to light reception.

[0036] The position of the pipeline position detection device 100 when the distance sensor 30 acquires 3D data and the attitude measurement device 40 performs measurement based on the trigger signal is defined as the "measurement position." The interval of the travel distance at which the trigger signal is issued is defined as the "measurement interval."

[0037] In acquiring three-dimensional data by the distance sensor 30, the four light emitters 31 are turned on, and light is emitted from the light emitters 31 toward the inner surface 1000i of the tube 1000. The light emitted from the light emitters 31 travels inside the tube 1000 while spreading along the optical axis, is reflected by the inner surface 1000i of the tube 1000, and is received by the light receiver 32.

[0038] The distance sensor 30 determines, for the light received by each light receiving element of the light receiver 32, the distance to the reflection point (each point on the inner surface 1000i of the tube 1000) and the direction from which the light came.

[0039] In many cases, the optical axis of the light received by the light receiver 32 is tilted with respect to the central axis of the tube 1000 due to the shaking of the mobile object 10 while traveling within the tube. Fig. 1A shows how the optical axis B (shown by the dashed line) of the light emitted by the light emitter 31 is tilted with respect to the central axis A (shown by the dashed line) of the tube 1000.

[0040] Even if a trigger signal is issued, the pipeline location detection device 100 continues to move without stopping. Then, when the pipeline location detection device 100 reaches the open end of the pipe 1000 on the measurement end side (for example, the inlet end), the operator stops pulling the towing rope 200, and stops the movement of the pipeline location detection device 100. This causes the pipeline location detection device 100 to complete measurements at multiple measurement positions from the open end of the pipe 1000 on the measurement start side to the open end on the measurement end side.

[0041] In S 3 , while the moving body 10 moves inside the pipe 1000 , the attitude measurement device 40 measures the attitude of the distance sensor 30 .

[0042] As described above, the attitude measurement device 40 measures the inclination (roll angle, pitch angle, yaw angle) of the attitude measurement device 40 with respect to the direction of gravity.

[0043] Based on the data thus acquired by the distance sensor 30 and the attitude measuring device 40, the computer 50 performs the following processing for identifying the pipeline position.

[0044] The subsequent processes may be performed in parallel with S1, S2, and S3, or may be performed after S1, S2, and S3 are completed.

[0045] In S4, the computer 50 generates the search data. Specifically, the computer 50 acquires the calculated values ​​of the distance to the inner surface 1000i of the pipe 1000 obtained by the distance sensor 30 and the measured values ​​of the attitude of the distance sensor 30 obtained by the attitude measuring instrument 40, which correspond to the multiple measured values ​​of the travel distance obtained by the distance measuring instrument 20 that differ from each other by a certain value.

[0046] The distance sensor 30 determines the distance to the reflection points (each point on the inner surface 1000i of the tube 1000) and the direction in which the light was coming from for the light received by each light receiving element of the receiver 32. The determined data is sent to the computer 50 as data obtained by the distance sensor 30 regarding the positions of the multiple reflection points (and therefore regarding the shape of the inner surface 1000i of the tube 1000).

[0047] In S5, the computer 50 corrects the calculated value of the distance to the inner surface 1000i of the pipe 1000 obtained from the distance sensor 30 for each of the multiple measurement values ​​of the movement distance of the moving body 10 based on the measurement value of the attitude of the distance sensor 30 obtained from the attitude measuring instrument 40, thereby obtaining a corrected value of the distance to the inner surface 1000i.

[0048] Specifically, the computer 50 corrects the three-dimensional data regarding the positions of the multiple reflection points (and therefore regarding the shape of the inner surface 1000i of the tube 1000) acquired by the distance sensor 30 with the measurement data in three axial directions (roll angle, pitch angle, yaw angle) relative to the direction of gravity acquired by the attitude measuring instrument 40.

[0049] Here, correction by posture data will be described with reference to Fig. 3A to Fig. 3C. Consider a case where the central axis A of the tube 1000 is not tilted with respect to the horizontal plane as shown in Fig. 3A. Assume that the optical axis B (indicated by a dashed line) of the light received by the light receiver 32 is significantly tilted upward with respect to the central axis A (indicated by a dashed line) of the tube 1000. In this case, the light emitted from the light emitter 31 is reflected back at the light reflection points indicated by circles in Fig. 3A on the inner surface 1000i of the tube 1000, and is received by the light receiver 32. The three-dimensional data acquired by the distance sensor 30 is data based on the distance sensor 30. Therefore, the three-dimensional data is three-dimensional data in which the reflection points are distributed as indicated by circles in Fig. 3B, and the tube 1000 is significantly tilted downward in front of the distance sensor 30. However, by correcting the three-dimensional data acquired by the distance sensor 30 with the measurement data (roll angle, pitch angle, yaw angle) acquired by the attitude measurement instrument 40, three-dimensional data that is estimated to be acquired when the central axis A of the tube 1000 and the optical axis B of the light received by the light receiver 32 are parallel can be obtained, as shown in Fig. 3C. In the obtained three-dimensional data, the central axis A of the tube 1000 is not tilted with respect to the horizontal plane.

[0050] In this way, the three-dimensional data acquired by the distance sensor 30 is corrected by the measurement data acquired by the attitude measuring instrument 40, and this is referred to as "three-dimensional corrected data." The three-dimensional corrected data is corrected data for a large number of reflection points acquired by one measurement at one measurement position. The three-dimensional corrected data matches the measurement data acquired by the distance sensor 30 when the optical axis of the light received by the light receiver 32 is oriented in the same direction as the central axis A of the pipe 1000.

[0051] Correction using the measurement data of the orientation measurement device 40 is performed on the acquired 3D data at each of the multiple measurement positions. Therefore, the same number of 3D correction data as the number of measurement positions, in other words, the same number as the number of measurements, is generated.

[0052] In S6, the computer 50 identifies the pipe position of the pipe 1000 for each of a plurality of measured values ​​of the moving distance of the moving body 10 using the acquired correction value of the distance to the inner surface 1000i.

[0053] Specifically, the computer 50 can generate visualization information that three-dimensionally displays the positions of a large number of light reflection points based on the three-dimensional correction data. Since the light reflection points are on the inner surface 1000i of the tube 1000, this visualization information can be regarded as an image that represents the shape of the inner surface 1000i of the tube 1000 in the form of a collection of a large number of points. Then, the shape of the inner surface 1000i of the tube 1000 can be detected from the shape of the collection of a large number of points. Visualization information can be generated for each measurement position, in other words, visualization information can be generated as many times as there are measurements.

[0054] 4A and 4B are simplified diagrams showing visualization information (for example, the above-mentioned three-dimensional correction data) generated by the computer 50 based on three-dimensional data acquired at a certain measurement position. FIG. 4A is a diagram showing the distance sensor 30 from the side, and FIG. 4B is a diagram showing the distance sensor 30 from the front. Note that the pipe 1000 is drawn with a dashed line in the diagram, but the pipe 1000 is not actually displayed in the visualization information generated by the computer 50. In this diagram, circles represent reflection points of light. Therefore, it can be said that a collection of circles represents the shape of the inner surface 1000i of the pipe 1000. Note that, although there are actually 300,000 reflection points, for example, only a small number of reflection points are shown in this diagram. Such visualization information can be generated for each measurement position. However, in this embodiment, visualization information does not necessarily have to be generated.

[0055] Next, the computer 50 sets a plurality of cross sections (cross sections perpendicular to the extension direction of the pipe 1000) at equal intervals in the same direction as the extension direction of the pipe 1000 in the three-dimensional correction data, and identifies, for example, the center position of each cross section. As a result, the computer 50 obtains a group of center positions consisting of a plurality of center positions.

[0056] 5A, cross sections x1, x2, ..., xF of the pipe 1000 are set at equal intervals on the 3D correction data represented by circles. The cross sections x1, x2, ..., xF are set at equal intervals from the distance sensor 30 forward (i.e., in the extension direction of the pipe 1000 and the measurement direction) with the distance sensor 30 as a reference. The interval between the cross sections x1, x2, ..., xF is defined as L. The interval L between the cross sections x1, x2, ..., xF is equal to, for example, the measurement interval (the interval between the measurement positions). For example, when the measurement interval is 10 cm, the interval L between the cross sections x1, x2, ..., xF is also 10 cm.

[0057] The center position C on the cross section x (see FIG. 5B) is calculated from the three-dimensional correction data within a certain range in the extension direction of the pipe 1000. The certain range here is equal to the interval L between the cross sections x1, x2, . . . xF. The center position C of the cross section x within the certain range is specified from the three-dimensional correction data within this certain range (i.e., the three-dimensional correction data within the range indicated by the diagonal lines in FIG. 5A). More specifically, the center position C of the cross section X is specified, for example, from the average value of the three-dimensional correction data within the certain range. The specified center position C on the three-dimensional correction data is regarded as the center position of the cross section x of the actual pipe 1000. In another example, the cross section x may be assumed to be circular or elliptical, and the center position of the cross section X of the pipe 1000 may be estimated from the three-dimensional correction data within the certain range.

[0058] Here, the cross section x is the center position of a certain range. Therefore, the center position C of the cross section x is specified based on data within a range of L / 2 both before and after the cross section x in the extension direction of the pipe 1000.

[0059] Note that the "certain range" which is the range of data used to calculate the center position C on cross section x is not limited to the same range as the interval L between cross sections x1, x2, ... xF as described above, but may be a narrower range. For example, the center position C on cross section x may be identified based on data within a range of L / 4 both before and after cross section x in the extension direction of pipe 1000. In other words, data that does not exist in the vicinity of cross sections x1, x2, ... xF may be ignored.

[0060] The computer 50 thus identifies center positions C1, C2,..., CF (see FIG. 5C) for all cross sections x1, x2,..., xF within the adopted range LA (see FIG. 5A). The computer 50 may adopt all the data that it has been able to acquire, or may adopt only data within a predetermined distance.

[0061] In this manner, from the 3D correction data obtained from one measurement, the center positions C1, C2, CF of each of the multiple cross sections x1, x2, . . . xF in the range LA in front of the distance sensor 30 are identified with the distance sensor 30 as a reference. As shown in Fig. 5C, the center positions C1, C2, . . . CF thus identified are arranged at equal intervals in the same direction as the extension direction of the pipe 1000.

[0062] A set of center positions C1, C2, . . . CF in multiple cross sections x1, x2, . . . xF identified from one measurement (in other words, identified from one piece of three-dimensional correction data) is defined as a "center position group."

[0063] The computer 50 obtains a center position group from the three-dimensional correction data for all the measurement positions. Therefore, the same number of center position groups as the number of measurement positions are obtained. Each center position group is specified based on which measurement it was obtained.

[0064] Next, the computer 50 superimposes the plurality of center positions in the order of measurement while shifting them in the moving direction of the pipeline position detection device 100 by a measurement interval.

[0065] Explaining with reference to FIG. 6, the center position group based on the second measurement is superimposed on the center position group based on the first measurement, shifted by the measurement interval, i.e., the interval between two measurement positions, in the moving direction d of the pipeline position detection device 100. Similarly, the center position group based on the third measurement and the center position group based on the fourth measurement are also superimposed, shifted by the measurement interval in the moving direction d of the pipeline position detection device 100. As a result, for example, in the cross section x4, the center position C1 (open triangle) of the cross section x1 among the center position group obtained from the first measurement, the center position C2 (filled triangle) of the cross section x2 among the center position group obtained from the second measurement, the center position C3 (open circle) of the cross section x3 among the center position group obtained from the third measurement, and the center position C4 (filled circle) of the cross section x4 among the center position group obtained from the fourth measurement are arranged.

[0066] Although only four center positions are drawn in Fig. 6, there are usually many more, and all of these center positions are stacked in this way. As a result, many center positions are placed on each cross section x1, x2,..., xF.

[0067] Next, the computer 50 identifies the average of multiple center positions present on the cross section xN as the average center position. For example, in Fig. 6, four center positions are provided on each of the cross sections x4 to xF-3 near the center of the pipe 1000, so the average of these four center positions is identified as the average center position. Note that center positions that are a predetermined distance or more away from other center positions may be ignored.

[0068] Finally, the computer 50 determines the position over the entire length of the tube 1000 by considering the average of the center positions of the multiple cross sections x1, x2, . . . xF as the center position of the actual cross section of the tube 1000.

[0069] Next, effects achieved by the pipeline location detecting device according to the first embodiment of the present disclosure will be described.

[0070] The pipeline position detection device 100 of the first embodiment includes the distance sensor 30, and therefore the distance sensor 30 can accurately detect the shape of the inner surface 1000i of the pipe 1000. Furthermore, the pipeline position detection device 100 includes an attitude measurement device 40 that measures the attitude of the distance sensor 30, and therefore by correcting the data acquired by the distance sensor 30 with the measurement data of the attitude measurement device 40, data of the reflection point of light that can be expected to be acquired when the optical axis of light received by the distance sensor 30 is oriented in the same direction as the central axis A of the pipe 1000 can be acquired as three-dimensional corrected data.

[0071] Furthermore, in a configuration in which the towing rope 200 is attached to the moving body 10, an operator can move the pipe position detection device 100 inside the pipe 1000 by pulling the towing rope 200. Therefore, measurements can be performed at a plurality of measurement positions inside the pipe 1000, and three-dimensional correction data can be obtained for each measurement position.

[0072] Furthermore, the pipeline position detection device 100 is equipped with a distance measuring device 20, which issues a trigger signal based on the measured moving distance, and the distance sensor 30 and the attitude measuring device 40 perform measurements based on the trigger signal, so that measurements can be performed at predetermined measurement intervals. Furthermore, since measurements are performed based on a trigger signal, data obtained by measurement can be associated with the measurement position at which the data was obtained and data processing can be performed.

[0073] Since the pipeline location detection device 100 has such a configuration, it is possible to obtain accurate data of the internal shape over a long distance in the extension direction of the pipe 1000. The pipeline location detection device 100 can implement a pipeline location detection method.

[0074] The pipeline location detection method of the first embodiment includes a step of performing measurements at a plurality of measurement positions determined based on the moving distance of the pipeline location detection device 100 while moving the pipeline location detection device 100 in the extension direction of the pipe 1000. Therefore, measurements can be performed over the entire extension direction of the pipe 1000 at predetermined measurement intervals.

[0075] As described above, the present pipeline position detection method includes a step of correcting data acquired by the distance sensor 30 at one measurement position using data measured by the attitude measuring device 40 at the same measurement position (correction step). According to the three-dimensional corrected data acquired in the correction step, a specific position (e.g., center position) on the cross section of the pipe 1000 can be identified with high accuracy.

[0076] Furthermore, as described above, the pipeline position exploration method may include setting cross sections x1, x2...xF in the 3D correction data, and acquiring a center position group consisting of center positions C1, C2...CF of each of the cross sections x1, x2...xF (center position group acquisition step).

[0077] Furthermore, the computer 50 may execute a correction step and a center position group acquisition step for data acquired at multiple measurement positions. Then, the computer 50 overlaps the multiple acquired center position groups while shifting them by the measurement interval by the pipeline position detection device 100, thereby overlapping multiple center positions C in each cross section x1, x2,...xF, and identifies an average center position that is the average of the overlapped multiple center positions C. With this method, it is possible to identify the average center position in each cross section x1, x2,...xF with high accuracy.

[0078] For example, TOF data acquired at a position 90 cm in front of the distance sensor 30 in the longitudinal direction of a pipe 1000 and TOF data acquired at a position 10 cm back from the position of the moving body 10, 100 cm in front of the distance sensor 30, are essentially three-dimensional data of the same cross section, so they should have the same value. For example, in Fig. 6, the four center positions of the position of cross section x5 should have the same value. Based on this concept, the cross section center position can be calculated with high accuracy by averaging the cross section center position multiple times.

[0079] The pipeline position detection method of this embodiment may identify the pipeline position by regarding the average of center positions acquired multiple times for a specific cross section as the center position of the actual cross section of the pipe 1000. With this configuration, the center position can be found with high accuracy, so that the pipeline position can be identified with high accuracy over the entire length of the pipe 1000.

[0080] [Second embodiment] Hereinafter, the same configuration as that of the pipeline location detection device 100 will not be described again, but only the configuration different from that of the pipeline location detection device 100 will be described. The same applies to the third and subsequent embodiments.

[0081] Fig. 7A is a diagram showing a state in which a pipeline location detection device 110 of the second embodiment is disposed inside a pipe 1000. As shown in Figs. 7B and 7C, this pipeline location detection device 110 differs from the pipeline location detection device 100 of the first embodiment in that a lens 71 is provided in front of the light-emitting body 31 as a condenser that suppresses the spread of light emitted from the light-emitting body 31. Note that the "forward" may be the direction in which the light emitted from the light-emitting body 31 travels.

[0082] The lens 71 is a converging device that suppresses the spread of the light emitted from the light emitter 31 (narrows the range of spread). The light emitted from the light emitter 31 and passing through the lens 71 is converged and travels forward from the lens 71 as shown by the arrow in FIG. 7A, compared to when the lens 71 is not present (FIG. 1A). When the lens 71 is not present in front of the light emitter 31 (FIG. 1A), the angle of spread of the light emitted from the light emitter 31 with respect to the optical axis B is, for example, about ±45°. On the other hand, when the lens 71 is present in front of the light emitter 31 and the light emitted from the light emitter 31 passes through the lens 71 (FIG. 7A), the angle of spread of the light after passing through the lens 71 with respect to the optical axis B is, for example, ±10° to 30°.

[0083] In this way, the lens 71 prevents the light emitted from the light emitter 31 from spreading, and the light is intensely incident on a narrow range up to a distant point, so the reflection intensity (amplitude of light) increases at the distant point where the light hits. Line L1 in Fig. 8A shows the change over time in the amplitude of the reflected light at the point where the light hits when there is no lens 71 (Fig. 1A). Line L2 in Fig. 8B shows the change over time in the amplitude of the reflected light at the point where the light hits when the light emitted from the light emitter 31 passes through the lens 71 (Fig. 7A). When the light passes through the lens 71, the amplitude of the reflected light fluctuates more.

[0084] As a result, the light intensity (amplitude) of the light received by the light receiver 32 from a distant location increases. Line L3 in FIG. 8A shows the change over time in the amplitude of the light received by the light receiver 32 when there is no lens 71 (FIG. 1A). In this case, the light received by the light receiver 32 is below the threshold at which distance can be measured, so the distance sensor 30 cannot measure the distance. Line L4 in FIG. 8B shows the change over time in the amplitude of the light received by the light receiver 32 when the light emitted from the light emitter 31 passes through the lens 71 (FIG. 7A). As shown in FIG. 8B, the amplitude of the light received by the light receiver 32 exceeds the threshold at which distance can be measured by the distance sensor 30 (shown by a dotted line). Therefore, by providing the lens 71 in front of the light emitter 31, it becomes possible to measure distances from a greater distance.

[0085] Furthermore, by suppressing the spread of the light emitted from the light emitter 31, the light can reach a greater distance inside the tube 1000. Therefore, it is possible to obtain three-dimensional data of the tube 1000 over a long distance with a single measurement.

[0086] Incidentally, when the spread of light is suppressed by the lens 71, there are cases where the light does not reach points close to the distance sensor 30; however, by adjusting the diameter or focal length of the lens 71, it is possible to emit light to nearby points.

[0087] A pipeline location detection method using the pipeline location detection device 110 of the second embodiment is similar to the pipeline location detection method of the first embodiment.

[0088] [Third embodiment] Fig. 9A is a diagram showing a state in which a pipeline location detection device 120 of the third embodiment is disposed inside a pipe 1000. As shown in Figs. 9B and 9C, this pipeline location detection device 120 differs from the pipeline location detection device 100 of the first embodiment in that a shielding tube 72 is provided in front of the light-emitting body 31 as a light collector that suppresses the spread of light emitted from the light-emitting body 31. The shielding tube 72 has a cylindrical shape and is provided so that its central axis extends in the front-rear direction. Note that the front-rear direction here refers to the direction in which the light emitted from the light-emitting body 31 travels as the front, and the opposite direction as the rear.

[0089] The shielding cylinder 72 may be a circular cylinder when viewed from the front, or a square cylinder when viewed from the front. In either case, the shielding cylinder 72 is a hollow cylinder with both front and rear ends open.

[0090] The shielding tube 72 is a converging device that suppresses the spread of light emitted from the light emitter 31 (narrows the range of spread). The light emitted from the light emitter 31 passes through the inside of the shielding tube 72 and travels forward. The light has a spread centered on the optical axis B. When the light traveling inside the shielding tube 72 hits the inner surface of the shielding tube 72, it is reflected there and travels further forward. Therefore, the light that has passed through the shielding tube 72 is converged and travels with less spread in front of the shielding tube 72 than if the shielding tube 72 were not present.

[0091] As in the configuration of the second embodiment, the spread of the light emitted from the light emitter 31 is suppressed in this way, so that the light is strongly incident on a narrow range up to the distant place, as in the case of Fig. 7A, and the reflection intensity at the place where the light is incident increases in the distant place. As a result, the intensity of the light received by the light receiver 32 from the distant place increases, and the amplitude of the light received by the light receiver 32 exceeds the threshold value at which the distance sensor 30 can measure the distance, making it possible to measure the distance in the distant place (see Fig. 8B).

[0092] Furthermore, by suppressing the spread of the light emitted from the light emitter 31, the light can reach a greater distance inside the tube 1000. Therefore, it is possible to obtain three-dimensional data of the tube 1000 over a long distance with a single measurement.

[0093] In addition, when the spread of light is suppressed by the shielding tube 72, there are cases where the light does not reach points close to the distance sensor 30; however, by adjusting the inner diameter or length of the shielding tube 72, it is possible to emit light to nearby points.

[0094] A pipeline location detection method using the pipeline location detection device 120 of the third embodiment is similar to the pipeline location detection method of the first embodiment.

[0095] [Fourth embodiment] Fig. 10A is a diagram showing a state in which a pipeline location detection device 130 of the fourth embodiment is disposed inside a pipe 1000. As shown in Figs. 10B and 10C, this pipeline location detection device 130 differs from the pipeline location detection device 100 of the first embodiment in that a lens 71 and a shielding tube 72 are provided in front of the light-emitting body 31 as a condenser that suppresses the spread of light emitted by the light-emitting body 31. In detail, similar to the configuration of the second embodiment, a lens 71 is provided in front of the light-emitting body 31. Furthermore, a shielding tube 72 is provided surrounding the lens 71. The shielding tube 72 is provided such that its central axis extends in the front-rear direction from the lens 71 toward the front.

[0096] The light emitted from the light emitter 31 and passing through the lens 71 and the shielding tube 72 is converged and less spreads forward than when only one of the lens 71 and the shielding tube 72 is provided.

[0097] In this way, the spread of the light emitted from the light emitter 31 is further suppressed, and thus the distance sensor 30 can measure distances over long distances, similar to the pipeline location detection device 110 and the pipeline location detection device 120. In this embodiment, the lens 71 and the shielding tube 72 are used in combination, so that it is possible to measure distances over even longer distances than a configuration having only either the lens 71 or the shielding tube 72.

[0098] A pipeline location detection method using the pipeline location detection device 130 of the fourth embodiment is similar to the pipeline location detection method of the first embodiment.

[0099] [Fifth embodiment] FIG. 11A is a diagram showing a state in which a pipeline position detection device 140 of the fifth embodiment is disposed inside a pipe 1000. As shown in FIG. 11B and FIG. 11C, the pipeline position detection device 140 is provided with a lens 71 and a shielding tube 72 in front of the light emitter 31. The pipeline position detection device 140 further includes an attitude adjuster 80 that adjusts the orientation of the light collector (the lens 71 in this embodiment) with respect to the distance sensor 30. More specifically, the attitude adjuster 80 may adjust the orientation of the moving body 10 in a direction (up and down direction and / or horizontal direction) perpendicular to the moving direction d of the moving body 10. In the pipeline position detection device 140, only one light emitter 31 is provided above the light receiver 32. Even if the pipeline position detection device 140 has only one light emitter 31 and one light receiver 32, it is possible to acquire data on the internal shape of the pipe 1000.

[0100] The attitude adjuster 80 may adjust the orientation of the shielding tube 72 with respect to the distance sensor 30. The attitude adjuster 80 may include a drive device such as a motor. The attitude adjuster 80 may be controlled by the computer 50.

[0101] In addition, in a configuration in which the pipeline position detection device has only one of the lens 71 and the shielding tube 72 as a focusing device (light collector), the attitude adjuster 80 may be configured to change the orientation of the focusing device. In a configuration in which the pipeline position detection device has one or both of the lens 71 and the shielding tube 72, the attitude adjuster 80 may not be provided with an attitude adjuster. In addition, the pipeline position detection device may not be provided with any of the lens 71, the shielding tube 72, and the attitude adjuster 80.

[0102] A pipeline location detection method using the pipeline location detection device 140 of the fifth embodiment is similar to the pipeline location detection method of the first embodiment.

[0103] [Sixth embodiment] FIG. 12A is a view of the pipeline position detection device 150 of the sixth embodiment seen from above. As shown in FIG. 12B and FIG. 12C, in this pipeline position detection device 150, two light emitters 31 are provided on the front surface of the distance sensor 30. The light emitters 31 are provided on both the left and right sides of the light receiver 32. In other words, the distance sensor 30 includes light emitters 31 that emit light toward the inner surface 1000i of the pipe 1000 on both sides of the direction perpendicular to the moving direction d of the moving body 10 in a plan view of the moving body 10. In addition, a lens 71 and a shielding tube 72 are provided in front of the light emitters 31 as a condenser that suppresses the spread of light emitted by the distance sensor 30. When implementing the pipeline position detection method of the present disclosure, the pipeline position detection device 150 may be arranged so that the line connecting the two light emitters 31 is horizontal.

[0104] In this way, since one light emitter 31 is provided on each of the left and right sides, the pipe position detection device 150 can easily accurately obtain data on the deformation in the left and right direction on the inner surface 1000i of the pipe 1000. To be more specific, the pipe 1000 may have deformation in the left and right direction, such as a bend in the left and right direction as shown in FIG. 12A or a step on the left and right sides of the inner surface 1000i. When such deformation in the left and right direction occurs, in a configuration in which the light emitter 31 is provided only at one position in the left and right direction, there is a risk that the light emitted from the light emitter 31 will not sufficiently hit the deformed part in the left and right direction, and even if it hits, there is a risk that it will not be reflected toward the light receiver 32.

[0105] However, since the light emitters 31 are provided on both the left and right sides as in this embodiment, even if the light from one light emitter 31 is unlikely to hit the deformed portion, the light from the other light emitter 31 may hit the deformed portion, and the light that hits the deformed portion may be reflected toward the light receiver 32. Therefore, it becomes easier to accurately obtain data (shape) of the deformed portion in the left-right direction on the inner surface 1000i of the tube 1000.

[0106] As a specific example, visualization information generated by computer 50 when tube 1000 is bent to the right as viewed from the light traveling direction is shown in Figures 13A and 13B. In these figures, open circles represent reflection points of light emitted from light emitter 31a on the left side, and filled-in circles represent reflection points of light emitted from light emitter 31b on the right side. Note that there are actually, for example, 300,000 reflection points, but these figures show only a small number of reflection points.

[0107] As shown in Figures 13A and 13B, the reflection points (black circles) of the light emitted from the right-side light emitter 31b are more numerous on the left side and fewer on the right side. On the other hand, the reflection points (white circles) of the light emitted from the left-side light emitter 31a are also numerous on the left side, but are relatively numerous on the right side as well. At least, the reflection points of the light emitted from the left-side light emitter 31a are more numerous than the reflection points of the light emitted from the right-side light emitter 31b. Therefore, when the tube 1000 is bent to the right as viewed from the light traveling direction as shown in Figure 13A, the light emitted from the left-side light emitter 31a is more effective in capturing the shape of the inner surface 1000i of the tube 1000.

[0108] On the other hand, although not shown, when the tube 1000 is bent to the left as viewed from the light traveling direction, the light emitted from the light emitter 31b on the right side is more effective.

[0109] From these facts, it can be seen that when the tube 1000 is curved in the left-right direction, providing the light-emitting bodies 31 on both the left and right sides is effective in capturing the shape of the inner surface 1000i of the tube 1000.

[0110] 12B, the number of light-emitting bodies 31 is only two, but more light-emitting bodies 31 may be provided. The pipeline position detection device 150 does not need to be provided with either or both of the lens 71 and the shielding tube 72. In a configuration in which at least one of the lens 71 and the shielding tube 72 is provided as a focusing device in front of the light-emitting body 31, a posture adjuster 80 that adjusts the orientation of the collector with respect to the distance sensor 30 may be provided, as in the fifth embodiment.

[0111] A pipeline location detection method using the pipeline location detection device 150 of the sixth embodiment is similar to the pipeline location detection method of the first embodiment.

[0112] [Seventh embodiment] FIG. 14A is a diagram of the pipeline location detection device 160 of the seventh embodiment when viewed from the side. As shown in FIG. 14B and FIG. 14C, in this pipeline location detection device 160, two light emitters 31 are provided on the front surface of the distance sensor 30. The light emitters 31 are provided one above and one below the light receiver 32. In other words, the distance sensor 30 includes light emitters that emit light toward the inner surface 1000i of the pipe 1000 on both sides of the direction perpendicular to the moving direction d of the moving body 10 in a side view of the moving body 10 in the distance sensor 30. In addition, a lens 71 and a shielding tube 72 are provided in front of the light emitters 31. When implementing the pipeline location detection method of the present disclosure, the pipeline location detection device 160 may be arranged so that the line connecting the two light emitters 31 is vertical.

[0113] In this way, since one light emitter 31 is provided at the top and one at the bottom, it is easy to accurately obtain data on the vertical deformation of the inner surface 1000i of the tube 1000. To be more specific, the tube 1000 may have a vertical bend as shown in FIG. 14A, or may have a vertical deformation due to steps at the top and bottom of the inner surface 1000i. If the light emitter 31 is provided at only one location in the vertical direction despite such vertical deformation, there is a risk that the light emitted from the light emitter 31 will not sufficiently hit the vertically deformed part, and even if it does hit, it may not be reflected toward the light receiver 32.

[0114] However, because the light emitters 31 are arranged above and below as in this embodiment, even if the light from one light emitter 31 does not easily strike the deformed portion, the light from the other light emitter 31 can easily strike the deformed portion, and the light that strikes the deformed portion may be reflected toward the light receiver 32. Therefore, it becomes easier to accurately obtain data on the deformation in the vertical direction on the inner surface 1000i of the tube 1000.

[0115] As a specific example, visualization information generated by computer 50 when tube 1000 is bent downward as viewed from the light traveling direction is shown in Figures 15A and 15B. In these figures, open circles represent reflection points of light emitted from upper light emitter 31a, and circles represent reflection points of light emitted from lower light emitter 31b. Note that, although there are actually 300,000 reflection points, these figures show only a small number of reflection points.

[0116] As shown in Figures 15A and 15B, the reflection points (circles) of the light emitted from the lower light emitter 31b are more numerous on the upper side and fewer on the lower side. On the other hand, the reflection points (open circles) of the light emitted from the upper light emitter 31a are also numerous on the upper side, but are also relatively numerous on the lower side. At least, the reflection points of the light emitted from the upper light emitter 31a are more numerous than the reflection points of the light emitted from the lower light emitter 31b. Therefore, when the tube 1000 is bent downward as shown in Figure 15A, the light emitted from the upper light emitter 31a is effective for capturing the shape of the inner surface 1000i of the tube 1000.

[0117] On the other hand, although not shown, when the tube 1000 is bent upward as viewed from the light traveling direction, the light emitted from the lower light emitter 31b is more effective.

[0118] From these facts, it can be seen that when the tube 1000 is bent in the vertical direction, providing the light emitters 31 on both the top and bottom sides is effective in capturing the shape of the inner surface 1000i of the tube 1000.

[0119] 15B, the number of light-emitting bodies 31 is only two, but more light-emitting bodies 31 may be provided. The pipeline position detection device 160 does not need to be provided with either or both of the lens 71 and the shielding tube 72. In a configuration in which at least one of the lens 71 and the shielding tube 72 is provided as a focusing device in front of the light-emitting body 31, a posture adjuster 80 that adjusts the orientation of the collector with respect to the distance sensor 30 may be provided, as in the fifth embodiment. A pipeline location detection method using the pipeline location detection device 160 of the seventh embodiment is similar to the pipeline location detection method of the first embodiment.

[0120] [Eighth embodiment] FIG. 16A is a diagram of a pipeline position detection device 170 of the eighth embodiment when viewed from the side. As shown in FIGS. 16B and 16C, in this pipeline position detection device 170, one light emitter 31 and one light receiver 32 are provided on the front side of the distance sensor 30. A lens 71 and a shielding tube 72 are provided in front of the light emitter 31. In addition, a rotating device 90 for rotating the distance sensor 30 is provided on the rear side of the distance sensor 30. In other words, the pipeline position detection device 170 further includes a rotating device 90 for rotating the light receiver 32 in a plane perpendicular to the optical axis B of the light emitted by the light emitter 31. When the rotating device 90 is operated, the distance sensor 30 rotates as shown by the arrow in FIGS. 16B and 16C. At that time, the light receiver 32 becomes the center of rotation, and the light emitter 31 rotates around the light receiver 32.

[0121] While the pipeline position detection device 170 moves inside the pipe 1000, the distance sensor 30 rotates continuously without stopping, and acquires three-dimensional data during the rotation. Alternatively, while the pipeline position detection device 170 moves inside the pipe 1000, the rotation of the distance sensor 30 stops at every predetermined rotation angle (e.g., 90°), and acquires three-dimensional data while stopped. This makes it possible to reduce the variation in data that occurs when the distance sensor 30 does not rotate.

[0122] In particular, in a configuration in which the light receiver 32 is on the central axis A of the tube 1000, the light emitter 31 rotates around the light receiver 32, thereby rotating around the central axis A of the tube 1000. Therefore, the number of data points of reflection points acquired by the distance sensor 30 and the measurement error become uniform in the circumferential direction of the tube 1000. Of course, even in a configuration in which the light receiver 32 is located at a position other than on the central axis A of the tube 1000, the number of data points of reflection points acquired by the distance sensor 30 and the measurement error can become more uniform in the circumferential direction of the tube 1000 by rotating the light emitter 31 around the light receiver 32 than when the light receiver 32 does not rotate in this manner.

[0123] 16B shows only one light-emitting body 31, but two or more light-emitting bodies 31 may be provided. In addition, the pipeline position detection device 170 does not need to be provided with one or both of the lens 71 and the shielding tube 72. In addition, when at least one of the lens 71 and the shielding tube 72 is provided as a focusing device in front of the light-emitting body 31, an attitude adjuster 80 that adjusts the orientation of the collector with respect to the distance sensor 30 may be provided, as in the fifth embodiment.

[0124] A pipeline position detection method using the pipeline position detection device 170 of the eighth embodiment is similar to the detection method of the first embodiment.

[0125] [Modifications of the first to eighth embodiments] Various modifications can be made to the above embodiments. For example, instead of a traction means such as the traction rope 200, a drive mechanism for self-propelling the moving body 10 may be used as a means for moving the moving body 10 inside the pipe 1000. The drive mechanism may include a motor.

[0126] Also, instead of the battery 60, a wire extending from the distance sensor 30 to the outside of the pipe 1000 may be provided as a power supply means.

[0127] Also, in addition to the computer 50 on the moving body 10, an additional computer may be provided outside the pipe 1000. In that case, for example, the computer 50 on the moving body 10 may be used to store data acquired by the distance sensor 30, and the additional computer may be used as a computer for three-dimensional data processing.

[0128] Also, instead of the computer 50 in the above embodiment, a computer with a simple function of temporarily acquiring data may be provided on the moving body 10. In this configuration, the computer on the moving body 10 immediately transmits all data to another computer provided outside the pipe 1000 via optical fiber or metallic cable while acquiring the data. The computer outside the pipe 1000 then receives and stores the data, and performs calculations to identify the pipe position.

[0129] The following supplementary notes are further disclosed regarding the above embodiment.

[0130] (Additional note 1) A moving body that moves inside the tube; a distance measuring device that measures a moving distance of the moving object; a distance sensor mounted on the moving body, emitting light toward an inner surface of the tube located in a direction opposite to the moving direction of the moving body, receiving the light reflected by the inner surface, and calculating a distance to the inner surface based on a time from light emission to light reception; an attitude measuring device that measures an attitude of the distance sensor; a computer that generates search data indicating each calculated value of the distance to the inner surface obtained by the distance sensor and each measured value of the attitude obtained by the attitude measuring device, in association with each of a plurality of measured values ​​of the movement distance obtained by the distance measuring device; A pipeline location detection device comprising: (Additional note 2) Further comprising a concentrator for suppressing the spread of light emitted by the distance sensor. Attachment 1. A pipeline location detection device. (Additional note 3) and further comprising an attitude adjuster for adjusting an orientation of the collector with respect to the distance sensor. The pipeline position detection device according to claim 2. (Additional note 4) the distance sensor includes a light-emitting body that emits light toward the inner surface on both sides of the distance sensor in a direction perpendicular to the moving direction of the moving body in a plan view of the moving body, 4. A pipeline position detection device according to any one of claims 1 to 3. (Additional note 5) the distance sensor includes a light-emitting body that emits light toward the inner surface on both sides of the distance sensor in a direction perpendicular to the moving direction of the moving body in a side view of the moving body, 5. A pipeline position detection device according to any one of claims 1 to 4. (Additional note 6) The distance sensor includes only one light emitter that emits light toward the inner surface and only one light receiver that receives light reflected by the inner surface. 4. A pipeline position detection device according to any one of claims 1 to 3. (Additional note 7) The present invention further includes a rotating device that rotates the light emitter around the light receiver within a plane perpendicular to an optical axis of the light emitted by the light emitter. 7. The pipeline position detection device according to claim 6. (Additional note 8) measuring a moving distance of the moving body by a distance measuring device while moving the moving body inside the pipe; a distance sensor mounted on the movable body, which emits light toward an inner surface of the pipe located in a direction opposite to the moving direction of the movable body, and receives the light reflected by the inner surface, calculates a distance to the inner surface based on a time from light emission to light reception by the distance sensor while the movable body is moved inside the pipe; measuring the attitude of the distance sensor by an attitude measuring device while moving the moving body inside the pipe; acquiring, by a computer, calculated values ​​of the distance to the inner surface obtained by the distance sensor and measured values ​​of the attitude obtained by the attitude measuring device, the calculated values ​​corresponding to a plurality of measured values ​​of the movement distance obtained by the distance measuring device, the measured values ​​differing from each other by a certain value; correcting, by the computer, the calculated value of the distance to the inner surface obtained for each of the plurality of measured values ​​of the moving distance based on the measured value of the attitude obtained, to obtain a corrected value of the distance to the inner surface; Identifying, by the computer, a pipeline position of the pipe for each of the plurality of measurements of the travel distance using a correction value of the distance to the inner surface obtained; A pipeline location detection method comprising:

[0131] The present disclosure is not limited to the above-mentioned embodiment. For example, two or more blocks shown in the block diagram may be integrated, or one block may be divided. Instead of executing two or more steps shown in the flowchart in chronological order as described, each step may be executed in parallel or in a different order depending on the processing capacity of the device executing each step, or as necessary. Other modifications are possible without departing from the spirit of the present disclosure.

[0132] The computer of the present invention can also be realized by a program, and the program can be recorded on a recording medium or provided via a network. [Explanation of symbols]

[0133] 100,110,120,130,140,150,160,170 Pipe location detection device 10 Mobile 20 Distance measuring device 21 Rotating section 30 Distance Sensor 31, 31a, 31b Illuminant 32 Receiver 40 Attitude measuring device 50 Computer 60 Battery 71 Lens 72 Shield tube 80 Posture adjuster 90 Rotating Equipment 200 Tow Rope 1000 tubes 1000i inside

Claims

1. A moving body that moves inside the tube; a distance measuring device that measures a moving distance of the moving object; a distance sensor mounted on the moving body, emitting light toward an inner surface of the tube located in a direction opposite to the moving direction of the moving body, receiving the light reflected by the inner surface, and calculating a distance to the inner surface based on a time from light emission to light reception; an attitude measuring device that measures an attitude of the distance sensor; a computer that generates search data indicating each calculated value of the distance to the inner surface obtained by the distance sensor and each measured value of the attitude obtained by the attitude measuring device, in association with each of a plurality of measured values ​​of the movement distance obtained by the distance measuring device; A pipeline location detection device comprising:

2. Further comprising a concentrator for suppressing the spread of light emitted by the distance sensor. The pipeline location detection device according to claim 1.

3. and further comprising an attitude adjuster for adjusting an orientation of the collector with respect to the distance sensor. The pipeline location detection device according to claim 2.

4. the distance sensor includes a light-emitting body that emits light toward the inner surface on both sides of the distance sensor in a direction perpendicular to the moving direction of the moving body in a plan view of the moving body, A pipeline position detection device according to any one of claims 1 to 3.

5. the distance sensor includes a light-emitting body that emits light toward the inner surface on both sides of the distance sensor in a direction perpendicular to the moving direction of the moving body in a side view of the moving body, A pipeline position detection device according to any one of claims 1 to 3.

6. The distance sensor includes only one light emitter that emits light toward the inner surface and only one light receiver that receives light reflected by the inner surface. A pipeline position detection device according to any one of claims 1 to 3.

7. The present invention further includes a rotating device that rotates the light emitter around the light receiver within a plane perpendicular to an optical axis of the light emitted by the light emitter. The pipeline position detection device according to claim 6.

8. measuring a moving distance of the moving body by a distance measuring device while moving the moving body inside the pipe; a distance sensor mounted on the movable body, which emits light toward an inner surface of the pipe located in a direction opposite to the moving direction of the movable body, and receives the light reflected by the inner surface, calculates a distance to the inner surface based on a time from light emission to light reception by the distance sensor while the movable body is moved inside the pipe; measuring the attitude of the distance sensor by an attitude measuring device while moving the moving body inside the pipe; acquiring, by a computer, calculated values ​​of the distance to the inner surface obtained by the distance sensor and measured values ​​of the attitude obtained by the attitude measuring device, the calculated values ​​corresponding to a plurality of measured values ​​of the movement distance obtained by the distance measuring device, the measured values ​​differing from each other by a certain value; correcting, by the computer, the calculated value of the distance to the inner surface obtained for each of the plurality of measured values ​​of the moving distance based on the measured value of the attitude obtained, to obtain a corrected value of the distance to the inner surface; Identifying, by the computer, a pipeline position of the pipe for each of the plurality of measurements of the travel distance using a correction value of the distance to the inner surface obtained; A pipeline location detection method comprising:

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