Inspection system, inspection method, and flight device

Abstract

An inspection system (1) according to the present invention comprises a patterned sign (10) installed in a cable tunnel (40) and a flight device (20) that flies autonomously in the cable tunnel (40), the flight device (20) comprising: a sensing unit (21) that recognizes an image of the sign (10); a first control unit (22) that uses the result of recognizing the image by the sensing unit (21) to process the image and generate a control signal for controlling the flight position; a second control unit (23) that converts the control signal into a drive signal for driving the flight device (20); and an inspection image photographing unit (24) that photographs an image for inspecting communication equipment (30) installed in the cable tunnel (40).

Description

[Technical Field]

[0001] The present disclosure relates to an inspection system and inspection method for equipment in a cable tunnel using a flying device, and the flying device. [Background technology]

[0002] Conventionally, communication tunnels (hereinafter referred to as "tunnels") are structures that house communication equipment that occupies an underground space. Like other social infrastructure facilities, communication equipment inside tunnels requires proper maintenance and management. Therefore, it is necessary to monitor the condition through periodic inspections and take appropriate measures in response to deterioration. Currently, for communication manholes (hereinafter referred to as "MHs"), which are smaller structures than tunnels, automated flight technology using flying devices such as UAVs (Unmanned Aerial Vehicles), including drones, has been established to reduce the number of people required for inspections. For example, Patent Document 1 describes an unmanned aircraft control system that controls an unmanned aircraft equipped with a sensor for detecting the distance to an object, and a method for controlling the unmanned aircraft control system.

[0003] Figure 17A is a schematic diagram illustrating the automatic flight of a flight device within a MH. In Figure 17A, rs indicates the road surface above the MH, fp indicates the flight path of the UAV, and sw indicates the pool of water below the MH. There is no lighting installed on the ceiling of the MH. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2018-160196 Summary of the Invention [Problem to be solved by the invention]

[0005] As mentioned above, automated flight technology for flying devices within tunnels has not yet been established, and the characteristics of underground structures differ between MH and tunnels. Figure 17B is a schematic diagram showing an image of automated flight of a flying device within a tunnel. Lights la are placed at regular intervals on the ceiling of the tunnel. fp indicates the flight path of the flying device. Figure 17C is a schematic diagram showing the interior of an MH, and Figure 17D is a cross-section of the tunnel. In Figure 17D, ufb is the upper floor of the tunnel, sfb is the side wall of the tunnel, ufb is the lower floor of the tunnel, and ft is the tunnel footing. Dust du has accumulated on the tunnel footing ft.

[0006] The differences between flying a flying device inside a MH and inside a tunnel are: (i) a tunnel has a larger space than a MH, and when a flying device flies inside a MH, a distance of a few meters is sufficient, as shown in Figure 17C, but inside a tunnel, it may fly a distance of several hundred meters, as shown in Figure 17D; (ii) as shown in Figure 17A, there is no lighting la in a MH, but as shown in Figure 17B, there is lighting la in a tunnel; and (iii) because a tunnel has a drainage function, there is a lot of dust du after drainage on the footing ft, as shown in Figure 17D.

[0007] The challenge is to establish a method for automatically flying a flying device in underground structures in a non-GPS environment, in tunnels with existing communication equipment such as cables, to inspect the communication equipment, etc. Furthermore, to enable long-distance flight of the flying device in an environment with a certain level of illumination, it is necessary to establish technologies such as flight speed and charging functions for the flying device. [Means for solving the problem]

[0008] The object of the present invention, which was made in consideration of the above circumstances, is to establish a system technology for automatically inspecting communication equipment, etc. inside a tunnel, which has the function of taking images inside the tunnel and the function of controlling the automatic flight of a flying device using sensors.

[0009] In order to solve the above problem, one embodiment of an automatic inspection system is an inspection system that uses a flying device, and includes: a patterned sign installed inside a telescope; and a flying device that flies automatically inside the telescope. The flying device includes a sensing unit that performs image recognition of the sign; a first control unit that performs image processing based on the image recognition results by the sensing unit and generates a control signal that controls the flight position; a second control unit that converts the control signal into a drive signal that drives the flying device; and an inspection image capture unit that captures inspection images of the communication equipment installed inside the telescope.

[0010] In order to solve the above problem, a flying device according to one embodiment includes a sensing unit that performs image recognition of a patterned sign installed in a tunnel, and a first control unit that performs image processing based on the image recognition result by the sensing unit and generates a control signal that controls the flight position. A flying device comprising: a second control unit that converts the control signal into a drive signal that drives the flying device; a drive unit that drives the flying device based on the drive signal; and an inspection image capture unit that captures inspection images of the communication equipment installed in the tunnel.

[0011] In order to solve the above problem, an inspection method according to one embodiment is an inspection method using a flying device, and includes the steps of: performing image recognition of patterned signs installed in a telecommunication tunnel using the flying device; performing image processing based on the image recognition results to generate a control signal for controlling the flight position; converting the control signal into a drive signal for driving the flying device; driving the flying device based on the drive signal; and taking inspection images of the communication equipment installed in the telecommunication tunnel. [Effects of the Invention]

[0012] The flight device can be flown automatically even in tunnels in non-GPS environments. [Brief explanation of the drawings]

[0013] [Figure 1]1 is a block diagram illustrating a configuration example of an inspection system according to an embodiment of the present disclosure. [Figure 2] FIG. 1 is a block diagram illustrating an example configuration of a flying device according to an embodiment of the present disclosure. [Figure 3] FIG. 1 is a diagram showing an overview of an inspection system using an autonomous flying device. [Figure 4] FIG. 1 is a diagram showing an image sensing environment inside a tunnel. [Figure 5A] 1 is a table explaining the standards for average illuminance inside a tunnel. [Figure 5B] 1 is a table illustrating standards for the spacing of fluorescent lamps in the general section. [Figure 5C] 1 is a table explaining the fluorescent lamp output standards for each cable tunnel. [Figure 6] FIG. 10 is a diagram showing an image capturing environment using lighting inside a cable tunnel. [Figure 7A] FIG. 10 is a diagram showing the installation positions of signs. [Figure 7B] A cross-sectional view of the installation location of the sign. [Figure 8] FIG. 10 is a diagram showing an example in which signs are installed in two locations on the ceiling of a cable tunnel. [Figure 9A] FIG. 10 is a diagram illustrating a configuration in which illumination light is collected using a reflecting lens. [Figure 9B] FIG. 10 is a cross-sectional view of a configuration in which light is collected using a reflecting lens. [Figure 10] FIG. 1 is a diagram showing the structure of a marker. [Figure 11] FIG. 1 is a diagram showing the structure of a marker. [Figure 12] FIG. 10 is a diagram showing the installation positions of signs. [Figure 13] FIG. 10 is a diagram illustrating the charging function of the flying device. [Figure 14] FIG. 10 is a block diagram showing an example configuration of a flying device further equipped with a charging function. [Figure 15] 10 is a flowchart illustrating an example of an inspection method performed by an inspection system according to an embodiment. [Figure 16] 3 is a block diagram showing a schematic configuration of a computer that functions as a first control unit. FIG. [Figure 17A] This is a schematic diagram that explains the concept of automatically flying a flying device within a MH. [Figure 17B] This is a schematic diagram showing an image of automatically flying a flying device inside a tunnel. [Figure 17C] FIG. 1 is a schematic diagram showing the inside of a MH. [Figure 17D] FIG. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. The present invention is not limited to the following embodiments, and various modifications can be made within the scope of the present disclosure.

[0015] FIG. 1 is a block diagram illustrating an example configuration of an inspection system according to an embodiment of the present disclosure.

[0016] 1, an inspection system 1 according to one embodiment includes a sign 10 and a flying device 20. The inspection system 1 uses the flying device 20 to inspect in-telephone cable communication facilities.

[0017] Sign 10 is a patterned sign installed inside the cable tunnel 40. In FIG. 1, an inverted triangle above the flying device 20 indicates that the flying device 20 performs image recognition of sign 10. As will be described later, the flying device 20 controls its flight position based on image information obtained by image recognition of sign 10. An upward light may be installed on the body of the flying device 20 to facilitate image recognition of sign 10.

[0018] 10 and 11 are diagrams showing the structure of a sign. The sign 10 is a structure installed on the cable tunnel ceiling 41. To facilitate image capture from below, the sign 10 may be a triangular prism structure. The surface of the sign 10 may be patterned to allow image processing based on brightness (for example, a checkered pattern as shown in FIG. 10), or may be patterned to allow image recognition based on shape (edges) (for example, a textured structure as shown in FIG. 11). The sign 10 is made of a material such as plastic, which allows for easy formation of a textured structure on its surface.

[0019] FIG. 2 is a block diagram illustrating an example configuration of a flying device according to an embodiment of the present disclosure.

[0020] The flying device 20 includes a sensing unit 21, a first control unit 22, a second control unit 23, an inspection image capturing unit 24, and a driving unit 25. The flying device 20 automatically flies within the tunnel.

[0021] The sensing unit 21 performs image recognition of the patterned signs 10 installed inside the tunnel. The sensing unit 21 transmits image information, which is the result of the image recognition, to the first control unit 22. The sensing unit 21 is a camera that performs image recognition of the signs 10. The camera may be a smart camera or an AI camera.

[0022] The first control unit 22 calculates optical flow using the image recognition results from the sensing unit 21 and generates a control signal to control the flight position based on the optical flow. Optical flow is a vector field representation of the temporally differentiable movement of an object in an image obtained through image recognition. In other words, optical flow is a vector obtained by estimating the movement of a part of an image or the overall movement based on common parts captured in two or more images. The first control unit 22 transmits a control signal to the second control unit 23 and also transmits a command to the inspection image capturing unit 24 to capture images of the communication equipment 30 in the telecommunications cable 40.

[0023] The second control unit 23 converts the control signal generated by the first control unit 22 into a drive signal that drives the flight device 20. The second control unit 23 transmits the drive signal to the drive unit 25.

[0024] The inspection image capturing unit 24 captures an inspection image of the communication equipment 30 installed in the telecommunications cable 40. The inspection image capturing unit 24 includes a camera (second camera) that captures an inspection image of the communication equipment, separate from the camera (first camera) that performs image recognition of the sign 10 of the sensing unit 21. The inspection image capturing unit 24 may record the captured inspection image in a storage medium provided inside or outside the inspection image capturing unit 24.

[0025] The driving unit 25 drives the flight device 20 based on the driving signal generated by the second control unit 23.

[0026] Figure 3 is a diagram showing an overview of an inspection system using an autonomous flying device 20. As shown in Figure 3, signs 10 and interior lighting 44 are installed on the cable tunnel ceiling 41, and the flying device 20, which has the image recognition function described above, uses a first camera to recognize the signs 10, thereby controlling its flight position for automatic flight and capturing inspection images of the communication equipment installed inside the cable tunnel 40 and the interior walls (ceiling, side walls, and floor) of the cable tunnel 40 using a second camera. The arrows in the figure indicate the flight path (direction) of the flying device 20. A floor ft is provided at the cable tunnel bottom 42.

[0027] FIG. 4 is a diagram showing the image sensing environment inside a tunnel 40. As shown in FIG. 4, cables, metal fittings, and wiring 43 are present on the side of the cut-and-cover tunnel 40a. Furthermore, the floor ft at the bottom 42 of the tunnel is subject to a large amount of dust du and dirt after drainage, which hinders image capture. For this reason, the optimal sensing location for the first camera inside the tunnel is the tunnel ceiling 41. Furthermore, inspection images of the cables, metal fittings, and wiring 43 on the side of the tunnel 40a are captured by a second camera.

[0028] Figure 5A is a table explaining the standards for average illuminance inside a tunnel. The average illuminance inside a tunnel is specified as 15 lux in the general section (the section where the tunnel is a typical rectangular parallelepiped) and 30 lux in the special section (the structural section of the tunnel where access to the ground is possible). Figure 5B is a table explaining the standards for fluorescent lamp placement intervals in the general section. Figure 5B specifies that general lighting fluorescent lamps should be installed at intervals of 10 m, and emergency fluorescent lamps should be installed at intervals of 50 m. Figure 5C is a table explaining the standards for fluorescent lamp output by tunnel. The fluorescent lamp output by tunnel is specified as 20 W or 40 W. "Rectangular" refers to a tunnel that is a typical rectangular parallelepiped. "Circular" refers to a tunnel with a circular cross section. "No. 1" and "No. 2" refer to the size of the cross section. "Parallel" installation direction means that the longitudinal direction of the fluorescent lamp is the same as the longitudinal direction of the cable tunnel, and "perpendicular" installation direction means that the longitudinal direction of the fluorescent lamp is perpendicular to the longitudinal direction of the cable tunnel, as shown in Figure 6.

[0029] FIG. 6 is a diagram showing an image capture environment using lighting inside a tunnel. In the environment shown in FIG. 6, 20W general-purpose fluorescent lamps (straight-tube fluorescent lamps 44a) are installed at 10m intervals in the general section of the tunnel 40, and the minimum illuminance in the space is approximately 15 lux (lx), thus satisfying the standards of FIGS. 5A to 5C described above. The required illuminance for the camera used for image recognition is approximately 3 lux (camera performance requires a minimum of 1 lux, and image recognition requires illuminance approximately three times the camera performance), so this environment is sufficient for image recognition. By also installing an overhead light on the flight device 20 itself, robust image recognition becomes possible.

[0030] Figure 7A is a diagram showing the installation position of the sign. Figure 7B is a cross-sectional view of the installation position of the sign. As shown in Figures 7A and 7B, in order to automatically control the flight device 20, the sign 10 is installed in a position where it is illuminated by fluorescent lamps 44b on the cable tunnel ceiling 41 and where it is not backlit when taking images from the flight device 20.

[0031] FIG. 8 is a diagram showing an example in which signs 10 are installed in two locations on the ceiling of a tunnel. As shown in FIG. 8, signs 10 are installed in two locations on the tunnel ceiling 41 that is illuminated by lighting. The flying device 20 controls its flight position by image recognition of the two signs installed in the two locations. Specifically, the flying device 20 recognizes the two signs 10 on the image and controls its flight position so that they are the same distance apart.

[0032] Fig. 9A is a diagram illustrating a configuration for focusing illumination light using a reflecting lens. Fig. 9B is a cross-sectional view of a configuration for focusing light using a reflecting lens. As shown in Figs. 9A and 9B, by providing a function for focusing illumination light in the tunnel 40 onto the sign 10 using a reflecting lens 45 or the like, the flying device 20 can easily recognize the sign 10 as an image.

[0033] Figure 12 is a diagram showing the installation position of a sign. As shown in Figure 12, it is possible to secure an installation position for a sign 10 on the cable tunnel ceiling 41. A sign 10 will be newly installed on the cable tunnel ceiling 41. Furthermore, although there is existing cable tunnel management equipment (intra-cable lighting 44, cables, metal fittings, and wiring 43 for management system wiring, etc.) on the cable tunnel ceiling 41, it is possible to secure a space of about several tens of centimeters wide from the cable tunnel management equipment as installation space for the sign 10.

[0034] FIG. 13 is a diagram illustrating the charging function of a flight device. As shown in FIG. 13, the inspection system 1a further includes charging points 47 installed at regular intervals within the cable tunnel 40. It is desirable that the charging points 47 have the function of contactless charging via electromagnetic coupling. FIG. 14 is a block diagram illustrating an example configuration of a flight device that also includes a charging function. The flight device 20a further includes a charging unit 26 that receives power from the charging points 47 during flight, enabling long-term automatic flight. The interval between charging points 47 is determined by the flight speed and battery capacity of the flight device 20. For example, if the charging points are installed at intervals of 50 m and the speed is 0.3 m / s, an aircraft with a continuous flight time of 180 seconds can fly continuously for approximately 60 m.

[0035] FIG. 15 is a flowchart showing an example of an inspection method executed by an inspection system according to an embodiment.

[0036] In S101, the sensing unit 21 performs image recognition of the sign 10 installed in the tunnel 40.

[0037] In S102, the first control unit 22 performs image processing based on the image recognition result by the sensing unit 21, and generates a control signal for controlling the flight position.

[0038] In S103, the second control unit 23 converts the control signal generated by the first control unit 22 into a drive signal for driving the flight device 20.

[0039] In S104, the driving unit 25 drives the flight device 20 based on the driving signal generated by the second control unit.

[0040] In S105, the inspection image photographing unit 24 photographs an inspection image of the communication equipment installed in the telecommunications cable 40.

[0041] In this way, the inspection system 1 according to the present disclosure allows the flight device 20 to fly automatically even in a tunnel in a non-GPS environment.

[0042] The first control unit 22 provided in the above-mentioned flight device 20 may be configured with dedicated hardware such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field-Programmable Gate Array), or may be configured with a processor, or may be configured to include both.

[0043] A computer capable of executing program instructions can also be used to cause the first control unit 22 to function. Fig. 16 is a block diagram showing a schematic configuration of a computer functioning as the first control unit 22. Here, the computer functioning as the first control unit 22 may be a general-purpose computer, a dedicated computer, a workstation, a PC (Personal Computer), an electronic notepad, etc. The program instructions may be program code, code segments, etc. for performing necessary tasks.

[0044] 16, the computer 100 includes a processor 110, a memory unit including a ROM (Read Only Memory) 120, a RAM (Random Access Memory) 130, and a storage 140, an input unit 150, an output unit 160, and a communication interface (I / F) 170. Each component is connected to each other via a bus 180 so as to be able to communicate with each other.

[0045] The ROM 120 stores various programs and various data. The RAM 130 temporarily stores programs or data as a working area. The storage 140 is configured with an HDD (Hard Disk Drive) or an SSD (Solid State Drive) and stores various programs including an operating system and various data. In the present disclosure, the programs related to the present disclosure are stored in the ROM 120 or the storage 140.

[0046] Specifically, the processor 110 is a CPU (Central Processing Unit), MPU (Micro Processing Unit), GPU (Graphics Processing Unit), DSP (Digital Signal Processor), SoC (System on a Chip), etc., and may be configured with multiple processors of the same or different types. The processor 110 reads a program from the ROM 120 or storage 140 and executes the program using the RAM 130 as a working area, thereby controlling the above components and performing various arithmetic processing. Note that at least a part of these processing contents may be realized by hardware.

[0047] The program may be recorded on a recording medium readable by the first control unit 22. If such a recording medium is used, the program can be installed in the first control unit 22. Here, the recording medium on which the program is recorded may be a non-transitory recording medium. The non-transitory recording medium is not particularly limited, and may be, for example, a CD-ROM, a DVD-ROM, a USB (Universal Serial Bus) memory, or the like. Furthermore, the program may be in a form that is downloaded from an external device via a network.

[0048] The following additional notes are provided regarding the above-described embodiments.

[0049] (Additional note 1) An inspection system using a flying device, Patterned signs installed inside the tunnel, A flight device that automatically flies within the tunnel, The flying device is an inspection system equipped with a first camera that performs image recognition of the sign, a control unit that performs image processing based on the image recognition results of the first camera, generates a control signal to control the flight position, and converts the control signal into a drive signal to drive the flying device, and a second camera that takes inspection images of communication equipment installed in the cable tunnel. (Additional note 2) The label is An inspection system as described in appendix 1, wherein the sign is a triangular prism structure, and the surface of the sign has a pattern that allows image recognition based on brightness or a pattern that allows image recognition based on shape. (Additional note 3) The label is They are installed in two places on the ceiling of the tunnel, The flying device is 3. The inspection system according to claim 1 or 2, wherein the flight position is controlled by image recognition of two signs installed in the two locations. (Additional note 4) Further, charging points are installed at regular intervals within the tunnel, An inspection system described in any one of appendix 1 to 3, wherein the flying device further comprises a battery that receives power from the charging point during flight. (Additional note 5) a first camera that performs image recognition of a patterned sign installed in the tunnel; A control unit that performs image processing based on the image recognition result by the first camera, generates a control signal to control the flight position, converts the control signal into a drive signal that drives the flight device, and drives the flight device based on the drive signal; a second camera for taking inspection images of communication equipment installed in the tunnel; A flying device comprising: (Additional note 6) The control unit 6. The flight device of claim 5, which calculates optical flow and generates the control signal. (Additional note 7) An inspection method using a flying device, comprising: By the flying device, performing image recognition on a patterned sign installed in the tunnel; A step of performing image processing based on the image recognition result and generating a control signal for controlling the flight position; converting the control signal into a drive signal that drives a flight device; Driving a flight device based on the drive signal; taking an inspection image of the communication equipment installed in the tunnel; Inspection methods including:

[0050] Although the above-described embodiments have been described as typical examples, it will be apparent to those skilled in the art that many modifications and substitutions can be made within the spirit and scope of the present disclosure. Therefore, the present invention should not be interpreted as being limited by the above-described embodiments, and various modifications or alterations are possible without departing from the scope of the claims. For example, multiple building blocks shown in the block diagrams of the embodiments can be combined into one, or one building block can be divided. [Explanation of symbols]

[0051] 1, 1a Inspection System 10 signs 20, 20a flight equipment 21 Sensing unit 22 First Control Section 23 Second Control Section 24 Inspection image capture unit 25 Drive unit 26 Live parts 30 Communication Equipment 40 Tunnel 40a Cut-and-cover tunnel (rectangular) 41 Tunnel ceiling 42 Tunnel bottom 43 Cables, hardware, and wiring 44 Tunnel interior lighting 44a LED straight tube fluorescent lamp 44b Fluorescent lamp 45 Reflective Lens 46 Haunch 47 charging points

Claims

1. An inspection system using a flying device, a sign with a pattern that is installed on the ceiling of the cable tunnel and that is irradiated by condensing the illumination light from the lighting on the ceiling with a reflecting lens; a flight device that automatically flies within the tunnel, The flying device is a sensing unit that performs image recognition of the sign; A first control unit that performs image processing based on the image recognition result of the sign by the sensing unit and generates a control signal to control the flight position; a second control unit that converts the control signal into a drive signal that drives the flight device; an inspection image capturing unit that captures an inspection image of communication equipment installed in the telecommunications tunnel; An inspection system equipped with:

2. The label is A triangular prism structure having the following on the surface of the sign:

2. The inspection system according to claim 1, wherein a pattern is provided that allows image recognition based on brightness, or a pattern is provided that allows image recognition based on shape.

3. Further, charging points are provided at regular intervals within the tunnel, The inspection system of claim 1 or 2, wherein the flying device further comprises a charging unit that receives power from the charging point during flight.

4. a sensing unit that is installed on the ceiling of the cable tunnel and that performs image recognition of a patterned sign that is illuminated by condensed light from a light source on the ceiling using a reflecting lens; A first control unit that performs image processing based on the image recognition result of the sign by the sensing unit and generates a control signal to control the flight position; a second control unit that converts the control signal into a drive signal that drives a flight device; a drive unit that drives the flight device based on the drive signal; an inspection image capturing unit that captures an inspection image of the communication equipment installed in the telecommunications tunnel; A flying device comprising:

5. The first control unit calculates an optical flow and generates the control signal.

5. The flying device according to claim 4.

6. An inspection method using a flying device, comprising: The flying device a step of performing image recognition on a patterned sign that is installed on the ceiling of the cable tunnel and illuminated by condensing illumination light from a light on the ceiling using a reflecting lens; A step of performing image processing based on the image recognition result of the sign and generating a control signal for controlling a flight position; converting the control signal into a drive signal that drives a flight device; Driving a flight device based on the drive signal; taking an inspection image of the communication equipment installed in the tunnel; Inspection methods including:

Images