Unmanned Aerial Vehicle Flight Support Equipment

Abstract

To provide a flight support device of an unmanned aircraft which can suppress falling of an unmanned craft in a manhole.SOLUTION: A flight support device 100 of an unmanned aircraft DR in a manhole 500 having a skeleton part 520 forming an underground space, and a neck part 510 which communicates a skeleton opening 520a provided above the skeleton part 520 with the ground and has a width in a horizontal direction narrower than the skeleton part 520 includes: an annular ground opening guiding member 10 which is engaged with a ground opening 510a on the upper end of the neck part 510; an annular skeleton opening guiding member 20 provided in the skeleton opening 520a; and a plurality of connection members 30 which connects the ground opening guiding member 10 to the skeleton opening guiding member 20, extends in a substantially vertical direction and is aligned in a circumferential direction of the neck part 510.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] This disclosure relates to a flight support device that supports the flight of an unmanned aerial vehicle inside a manhole. [Background technology]

[0002] Conventionally, the mainstream method for inspecting underground structures such as sewer pipes installed underground is for workers to enter the pipes through manholes and conduct visual inspections, but there has been a need to reduce the labor required for workers to enter underground structures and ensure safety when workers perform underground work. In recent years, therefore, a method has been developed in which an unmanned aerial vehicle flies inside an underground structure and photographs the structure. In this method, the inspection of the underground structure is carried out by a person outside the underground structure checking the image of the structure photographed by the unmanned aerial vehicle (Non-Patent Document 1 and Non-Patent Document 2).

[0003] Non-Patent Document 1 proposes an unmanned aerial vehicle that can fly inside sewer pipes. However, it cannot be said that the automatic flight technology for the unmanned aerial vehicle to automatically fly from the ground through a manhole and enter the pipe connected to the manhole has been sufficiently established.

[0004] In response to this, Non-Patent Document 2 proposes a method for automatically entering a manhole body from the ground and inspecting the inside of a communication manhole. However, the diameter of a manhole is only a few meters at most (Non-Patent Document 3), and a communication manhole has a standard width of only about 70 cm, especially at a part called the neck (Non-Patent Document 2), making it a narrow space for an unmanned aerial vehicle to fly. In this narrow space, if an unmanned aerial vehicle comes into contact with the wall of the manhole neck, there is a risk that the main body or propeller guard of the unmanned aerial vehicle will get caught on the wall and crash, because the wall of the concrete neck has minute irregularities. Furthermore, because the neck is equipped with accessories such as steps for workers to ascend and descend (Non-Patent Document 3), there is a risk that the unmanned aerial vehicle will come into contact with these accessories and crash. Therefore, high-precision operation is required to prevent the unmanned aerial vehicle from colliding with the wall of the narrow space or the accessories attached to the wall.

[0005] Also, Non-Patent Document 2 proposes a method of autonomously controlling an unmanned aerial vehicle to automatically enter and exit the body of a manhole, and uses images from a camera mounted on the unmanned aerial vehicle for the entry and exit. However, since the body of a manhole is an underground structure, it is a dark space, and it was sometimes difficult to accurately determine the location of the entrance to the neck of the manhole using images from the camera mounted on the unmanned aerial vehicle. [Prior art documents] [Non-patent literature]

[0006] [Non-Patent Document 1] Yoshihiko Tanito and Hiroaki Inagaki, "Development of a drone capable of operating in enclosed spaces such as sewer pipes," Proceedings of the 29th Trenchless Technology Research Conference, 2018, pp.25-32 [Non-Patent Document 2] Daisuke Uchibori, Yuomi Hamano, Chihiro Kazato, Masashi Nakagawa, "Development of automatic inspection technology for communication manholes using drones", Proceedings of the Construction Robot Symposium, Vol. 19, O2-2, 2019. [Non-Patent Document 3] "Standard Structural Drawings for Sewerage Works", Hadano City Waterworks Bureau, 2017 Summary of the Invention [Problem to be solved by the invention]

[0007] As such, when using unmanned aerial vehicles to inspect underground structures, there is a need for technology that allows the unmanned aerial vehicle to move within the narrow neck of a manhole and easily return to the neck from the main body using autonomous control, but this has been difficult to achieve using the above-mentioned prior art alone.

[0008] Therefore, in consideration of the above points, the object of the present disclosure is to provide a flight support device for unmanned aerial vehicles that can prevent the unmanned aerial vehicles from falling into manholes. [Means for solving the problem]

[0009] In order to solve the above problems, the flight support device for an unmanned aerial vehicle according to the present disclosure includes: A flight support device for an unmanned aerial vehicle in a manhole having a body portion forming an underground space and a neck portion having a horizontal width narrower than that of the body portion, the neck portion connecting a body opening provided at an upper portion of the body portion to the ground, an annular ground opening guide member that engages with the ground opening at the upper end of the neck; a ring-shaped body opening guide member disposed in the body opening; a plurality of connecting members extending in a substantially vertical direction and arranged in a circumferential direction of the neck portion, the connecting members connecting the ground opening guide member and the frame opening guide member; The present invention is characterized by comprising: Effect of the Invention

[0010] According to the present disclosure, it is possible to provide a flight support device for an unmanned aerial vehicle that can prevent the unmanned aerial vehicle from crashing into a manhole. [Brief description of the drawings]

[0011] [Figure 1] A front cross-sectional view showing the state in which a flight support device for an unmanned aerial vehicle according to the first embodiment of the present disclosure is installed in the neck of a manhole. [Diagram 2] FIG. 1 is a perspective view of a flight support device for an unmanned aerial vehicle according to a first embodiment of the present disclosure. [Diagram 3] This is an oblique view of an unmanned aerial vehicle flight support device according to the first embodiment of the present disclosure installed on the neck of a manhole, as viewed from the ground. [Figure 4A] FIG. 2 is a detailed view of part A in FIG. [Figure 4B] FIG. 2 is a detailed view of part B in FIG. [Figure 5A] A front cross-sectional view showing a flight support device for an unmanned aerial vehicle according to a second embodiment of the present disclosure installed in the neck of a manhole. [Figure 5B] A plan view showing the state in which a flight support device for an unmanned aerial vehicle according to a second embodiment of the present disclosure is installed at the neck of a manhole. [Figure 6] A plan view showing the state in which the propeller guard of the unmanned aerial vehicle abuts against the connecting member. [Figure 7] This is a model for determining the condition (G>0) under which the propeller guard of an unmanned aerial vehicle does not come into contact with the cylindrical wall of the neck of a manhole when the propeller guard is circular in plan view. [Figure 8] This is a model for determining the condition (G>0) under which the propeller guard of an unmanned aerial vehicle does not come into contact with the cylindrical wall of the neck of a manhole when the propeller guard has a polygonal shape in a plan view. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, a flight support device 100 for an unmanned aerial vehicle according to a first embodiment of the present disclosure will be described with reference to the drawings.

[0013] In this embodiment, the upward direction of the flight support device 100 for the unmanned aerial vehicle is the upward direction in Fig. 1, and the downward direction is the downward direction in Fig. 1. The radial direction is a direction along a straight line perpendicular to the central axis O (see Figs. 7 and 8) of the neck 510 of the manhole 500 shown in Fig. 1 to which the flight support device 100 for the unmanned aerial vehicle according to this embodiment is attached, and the radially outward direction is a direction away from the central axis O of the neck 510 along the straight line, and the radially inward direction is a direction toward the central axis O of the neck 510 along the straight line.

[0014] 1, the manhole 500 to which the flight support device 100 for the unmanned aerial vehicle according to this embodiment is attached has a substantially rectangular parallelepiped body 520 forming an underground space, and a substantially cylindrical neck 510 that connects a body opening 520a provided at the top of the body 520 to the ground and has a horizontal width narrower than that of the body 520. The neck 510 has a cylindrical tube wall 511, a lid receiving member 514 that is disposed at the upper end of the tube wall 511 and into which an iron lid (not shown) is fitted, and a step 512 provided at one location in the circumferential direction on the inner surface of the tube wall 511.

[0015] The step 512 is provided so that an operator can enter from the ground opening 510a of the neck 510, descend inside the neck 510, and enter the body 520. In this embodiment, as shown in FIG. 3 and the like, the step 512 protrudes radially inward from the inner surface of the tube wall 511 at one circumferential location on the tube wall 511, and is arranged in a vertical line. The manhole 500 to which the flight support device 100 of the unmanned aerial vehicle according to this embodiment is attached is a communication manhole in which a communication cable or the like is laid in the duct 530, and the inside dimension (diameter) of the tube wall 511 of the neck 510 is about 60 cm to 70 cm, and the height of the tube wall 511 is about 60 cm. The size of the neck 510 is not limited to the above-mentioned size, and can be arbitrarily changed depending on the purpose of installation of the manhole 500, etc.

[0016] Body 520 of manhole 500 is made of reinforced concrete, with horizontal interior dimensions of approximately 2.3 m × 1.3 m and vertical interior dimensions of approximately 1.5 m. Body opening 520a is provided at the top of body 520, connecting body 520 to the ground via neck 510.

[0017] A pipe 530 is buried in the ground through a wall opening 520b provided in a vertical wall of the body part 520. In this embodiment, a communication cable is laid in the pipe 530 and extends to an adjacent manhole. For example, metal fittings for fixing the communication cable and a ladder for a worker to move to the neck part 510 through the body opening 520a can be installed in the body part 520.

[0018] As shown in Figure 2, the flight support device 100 for an unmanned aerial vehicle in this embodiment comprises a ground opening guide member 10 formed in a ring shape, a body opening guide member 20 also formed in a ring shape, and a plurality of connecting members 30 that extend approximately vertically and are arranged circumferentially around the neck 510 to connect the ground opening guide member 10 and the body opening guide member 20.

[0019] In this embodiment, the ground opening guide member 10 has a substantially circular shape and engages with the ground opening 510a at the upper end of the neck 510. More specifically, as shown in Fig. 4A, the ground opening guide member 10 is attached to the neck 510 by abutting against the upper surface of a lid receiving member 514 that is disposed at the upper end of a tubular wall portion 511 constituting the neck 510 and into which an iron lid (not shown) is fitted. The ground opening guide member 10 abuts against the upper surface of the lid receiving member 514, so that the flight support device 100 of the unmanned aerial vehicle is positioned in the vertical direction.

[0020] In this embodiment, the neck 510 includes a tube wall 511, a lid receiving member 514, and a step 512. The lid receiving member 514 is disposed so that its upper end is at the same height as the road surface RS, and forms a ground opening 510a that connects the inside of the neck 510 to the ground. However, this is not limited to the embodiment, and for example, the upper end of the lid receiving member 514 may be formed at a height position lower than the road surface RS, and the outer edge of the ground opening guide member 10 may abut against the outer edge of the ground opening 510a on the road surface RS. Also, the upper end of the lid receiving member 514 may be formed at a height position higher than the road surface RS, and the outer edge of the ground opening guide member 10 may abut against the upper end of the lid receiving member 514.

[0021] In this embodiment, the body opening guide member 20 has a substantially circular shape, and is disposed so that the outer edge abuts against the inner surface of the body opening 520a, as shown in Fig. 4B. With this configuration, the lower end of the flight support device 100 of the unmanned aerial vehicle is positioned in the radial direction.

[0022] In this embodiment, a light emitting unit (not shown) is built into the ground opening guide member 10 and the body opening guide member 20. The light emitting unit can be, for example, a light emitting diode (LED) element. By providing the light emitting unit in the ground opening guide member 10, the ground opening guide member 10 can be brightly and conspicuously displayed against the road surface RS, so that the position of the edge of the ground opening 510a near the ground opening guide member 10 can be easily recognized using an image of a camera mounted on the unmanned aerial vehicle DR. Therefore, when the unmanned aerial vehicle DR enters the neck 510 of the manhole 500 from the ground, the position of the edge of the ground opening 510a (i.e., the entrance position when entering the manhole 500 from the ground) can be accurately recognized, so that the autonomous control of the unmanned aerial vehicle DR can be stabilized.

[0023] Furthermore, since the body opening guide member 20 is provided with a light emitting unit, the body opening guide member 20 can be brightly highlighted in the dark body section 520, making it easier to recognize the position of the edge of the body opening 520a near the body opening guide member 20 using an image from a camera mounted on the unmanned aerial vehicle DR. Therefore, when the unmanned aerial vehicle DR that has entered the body section 520 passes through the neck section 510 and attempts to return to the ground, the position of the edge of the body opening 520a (i.e., the exit position when attempting to return from the body section 520 to the ground) can be accurately recognized, and therefore the autonomous control of the unmanned aerial vehicle DR can be stabilized.

[0024] Instead of being provided with a light-emitting portion, the ground opening guide member 10 and the body opening guide member 20 may be colored in a primary color, for example, red, blue, or green. By coloring the ground opening guide member 10 and the body opening guide member 20 in a primary color, the ground opening guide member 10 and the body opening guide member 20 can be brightly illuminated to make them stand out against the road surface RS and the body part 520. Therefore, the unmanned aerial vehicle DR can accurately recognize the positions of the edges of the ground opening 510a and the body opening 520a, and the autonomous control of the unmanned aerial vehicle DR can be stabilized.

[0025] The ground opening guide member 10 and the body opening guide member 20 may have a reflecting material on the surface, which reflects light irradiated from the unmanned aerial vehicle DR, instead of a light emitting portion. By providing the ground opening guide member 10 and the body opening guide member 20 with a reflecting material, the ground opening guide member 10 and the body opening guide member 20 can be made bright and conspicuous against the road surface RS and the body portion 520 by reflecting the light irradiated from the unmanned aerial vehicle DR even if they are not self-emitting. Note that the light emitting portion, the primary color coloring, and the reflecting material may be provided only on one of the ground opening guide member 10 or the body opening guide member 20.

[0026] The above-mentioned ground opening guide member 10 and the body opening guide member 20 are connected by a plurality of connecting members 30 that extend substantially vertically and are arranged in the circumferential direction of the neck portion 510. In this way, by connecting the ground opening guide member 10 and the body opening guide member 20 with the connecting members 30 that extend vertically, the propeller guard 610 (see FIG. 6) of the unmanned aerial vehicle DR can be configured to contact only the connecting members 30 without directly contacting the tube wall portion 511 of the neck portion 510. Since the tube wall portion 511 of the neck portion 510 is made of concrete and has minute irregularities on its surface, if the propeller guard 610 directly contacts the tube wall portion 511, a large frictional force acts on the unmanned aerial vehicle DR, which may cause the unmanned aerial vehicle DR to crash. In this embodiment, by connecting the ground opening guide member 10 and the body opening guide member 20 with the connecting members 30, the propeller guard 610 is prevented from directly contacting the tube wall portion 511, and the crash of the unmanned aerial vehicle DR can be suppressed.

[0027] The connecting member 30 preferably has a substantially cylindrical or polygonal prism shape, and if it has a substantially polygonal prism shape, it is preferable that it has a large number of corners. With this configuration, it is possible to prevent the propeller guard 610 (see FIG. 6) of the unmanned aerial vehicle DR from getting caught on the sharp corners and crashing when it comes into contact with the connecting member 30.

[0028] 3, the connecting member 30 is configured to have a wide spacing portion 31 in which the spacing between adjacent connecting members 30 is wider than the spacing between other connecting members at the circumferential position where the step 512 is provided. With this configuration, even if the step 512 protrudes radially inward from the cylindrical wall portion 511 of the neck portion 510, the flight support device 100 of the unmanned aerial vehicle DR can be easily attached to the neck portion 510. Even if the step 512 protrudes radially inward from the cylindrical wall portion 511, if the unmanned aerial vehicle is a predetermined size or smaller, there is sufficient flight space, so the unmanned aerial vehicle DR can fly inside the neck portion 510.

[0029] In the above configuration, although there is a possibility that the propeller guard 610 of the unmanned aerial vehicle DR may come into contact with the step 512, the step 512 often does not have an uneven surface like the concrete cylindrical wall portion 511, and does not have any sharp corners. Therefore, a certain degree of fall prevention effect can be obtained by attaching the flight support device 100 to the unmanned aerial vehicle DR.

[0030] The connecting member 30 can be formed from, for example, steel coated with a fluororesin such as polytetrafluoroethylene (PTFE) or aluminum. By using these materials, it is possible to reduce the frictional force acting on the unmanned aerial vehicle DR when the propeller guard 610 of the unmanned aerial vehicle DR comes into contact with the connecting member 30. Therefore, it is possible to prevent the unmanned aerial vehicle DR from crashing due to contact between the unmanned aerial vehicle DR and the connecting member 30.

[0031] In this embodiment, the flight support device 100 of the unmanned aerial vehicle DR is attached so that the ground opening guide member 10 abuts against the upper surface of the lid receiving member 514. With this configuration, as shown in Fig. 4A, the lid receiving member 514 is positioned outside the flight area of ​​the unmanned aerial vehicle DR. Therefore, it is possible to prevent the propeller guard 610 of the unmanned aerial vehicle DR from coming into contact with the lid receiving member 514 and crashing.

[0032] As described above, the present embodiment is a flight support device 100 for an unmanned aerial vehicle DR in a manhole 500 having a body part 520 forming an underground space and a neck part 510 having a horizontal width narrower than that of the body part 520, which connects a body opening 520a provided at the upper part of the body part 520 with the ground, and is configured to include an annular ground opening guide member 10 that engages with the ground opening 510a at the upper end of the neck part 510, an annular body opening guide member 20 that is disposed at the body opening 520a, and a plurality of connecting members 30 that extend in a substantially vertical direction and are arranged in the circumferential direction of the neck part 510, which connect the ground opening guide member 10 and the body opening guide member 20. By adopting such a configuration, it is possible to suppress the propeller guard 610 of the unmanned aerial vehicle DR from contacting the tube wall part 511 of the neck part 510, and suppress the crash of the unmanned aerial vehicle DR.

[0033] In this embodiment, the ground opening guide member 10 is configured to abut on the upper surface of the lid receiving member 514 disposed at the upper end of the neck portion 510. By adopting such a configuration, the lid receiving member 514 is positioned outside the flight area of ​​the unmanned aerial vehicle DR, so that it is possible to prevent the propeller guard 610 of the unmanned aerial vehicle DR from coming into contact with the lid receiving member 514 and crashing.

[0034] In this embodiment, the multiple connecting members 30 are configured to have wide spacing portions 31 in which the spacing between adjacent connecting members 30 is wider than the spacing between other connecting members at circumferential positions corresponding to steps 512 provided on the inner surface of the neck 510. By employing such a configuration, even if the steps 512 protrude radially inward from the cylindrical wall portion 511 of the neck 510, the flight support device 100 of the unmanned aerial vehicle DR can be easily attached to the neck 510.

[0035] In this embodiment, the body opening guide member 20 is configured to abut against the inner surface of the body opening 520a. By adopting such a configuration, the radial position of the lower end of the flight support device 100 of the unmanned aerial vehicle DR can be easily determined, so that the attitude of the flight support device 100 of the unmanned aerial vehicle DR can be stabilized.

[0036] In this embodiment, each of the multiple connecting members 30 has a substantially cylindrical shape and is configured to be coated with fluororesin or made of aluminum. By adopting such a configuration, it is possible to reduce the coefficient of friction between the propeller guard 610 of the unmanned aerial vehicle DR and the connecting member 30, and therefore it is possible to suppress the application of a large frictional force to the unmanned aerial vehicle DR when the unmanned aerial vehicle DR comes into contact with the connecting member 30 during flight.

[0037] In this embodiment, at least one of the ground opening guide member 10 and the body opening guide member 20 is configured to have a light emitting unit. By adopting such a configuration, the ground opening guide member 10 and the body opening guide member 20 can be made bright and conspicuous relative to the surroundings, so that the autonomous control of the unmanned aerial vehicle DR can be stabilized when entering the manhole 500 from the ground or returning from the body 520 to the ground, using an image from a camera mounted on the unmanned aerial vehicle DR.

[0038] Next, a flight support device 200 for an unmanned aerial vehicle according to a second embodiment of the present disclosure will be described with reference to FIGS. 5A to 8. FIG.

[0039] The flight support device 200 for an unmanned aerial vehicle according to this embodiment is similar to the first embodiment except for three points: 1. the ground opening guide member 10 is placed on two square bars 140 spanning the ground opening 510a, not on the upper surface of the lid receiving member 514, 2. the connecting member 30 is disposed radially inside the step 512, and no wide spacing portion 31 is provided, and 3. the body opening guide member 20 does not abut against the inner surface of the body opening 520a. Therefore, the following description will focus on the differences from the first embodiment.

[0040] As shown in Figures 5A and 5B, the flight support device 200 for the unmanned aerial vehicle in this embodiment comprises a ground opening guide member 10 formed in a ring shape, a body opening guide member 20 also formed in a ring shape, a plurality of connecting members 30 extending approximately vertically and arranged circumferentially around the neck portion 510 to connect the ground opening guide member 10 and the body opening guide member 20, and two square bars 140 spanning the ground opening 510a and supporting the ground opening guide member 10.

[0041] The two square bars 140 have a substantially rectangular cross-sectional shape, and are configured to be sufficiently long with respect to the diameter of the ground opening 510a, as shown in Fig. 5B. In this embodiment, as shown in Fig. 5B, the two square bars 140 are arranged parallel to each other on the road surface RS at an interval corresponding to the diameter of the ground opening guide member 10, and the lower surface of the outer edge of the ground opening guide member 10 is placed in contact with the upper surface of the square bar 140.

[0042] The flight support device 200 of the unmanned aerial vehicle used in this embodiment is configured so that the outer diameters of the ground opening guide member 10 and the body opening guide member 20 are smaller than the distance between the radially inner end of the step 512 in the neck portion 510 and the inner surface of the neck portion 510 facing the step 512. With this configuration, as shown in FIG. 5B, the flight support device 200 of the unmanned aerial vehicle DR can be accommodated in the neck portion 510 so as not to overlap with the step 512 in the radial direction. Therefore, the unmanned aerial vehicle DR that enters the neck portion 510 from the ground can reach the body portion 520 through the inside of the neck portion 510 without coming into contact with the step 512. In this embodiment, the connecting members 30 are arranged at equal intervals in the circumferential direction of the ground opening guide member 10 and the body opening guide member 20. However, this is not limited to this embodiment, and the connecting members 30 may be arranged at different intervals in the circumferential direction of the ground opening guide member 10 and the body opening guide member 20.

[0043] Furthermore, in this embodiment, the two square bars 140 are arranged parallel to each other on the road surface RS at an interval corresponding to the diameter of the ground opening guide member 10, so that even if the diameter of the ground opening guide member 10 is smaller than the inner diameter of the neck portion 510, the square bar 140 can be placed so that the lower surface of the outer edge of the ground opening guide member 10 abuts against the upper surface of the square bar 140.

[0044] The cross-sectional shape of the two square bars 140 is not limited to a substantially rectangular shape, and various other shapes that can be stably arranged on the road surface RS may be adopted. Also, the ground opening guide member 10 may be configured to be supported at three or more points by three or more square bars 140. The square bars 140 may be made of various other materials, such as aluminum, that have the strength to support the flight support device 200 of the unmanned aerial vehicle DR.

[0045] FIG. 6 shows a state in which the propeller guard 610 of the unmanned aerial vehicle DR is in contact with the connecting member 30. The unmanned aerial vehicle DR used in this embodiment includes a main body 605 including a control unit, a propeller unit 608, a fixed arm unit 620 for fixing the propeller unit 608, and a propeller guard 610 for protecting the propeller unit 608. If the outer edge of the propeller guard 610 does not protrude radially outward from the connecting member 30 when the propeller guard 610 contacts the connecting member 30, the propeller guard 610 will not contact the tube wall portion 511 of the neck portion 510 or the step 512. Therefore, the propeller guard 610 can only come into contact with the connecting member 30, which has a small frictional force at the time of contact, and therefore it is possible to prevent the unmanned aerial vehicle DR from crashing due to a large frictional force acting on the propeller guard 610. In addition, it is possible to stabilize the autonomous control of the unmanned aerial vehicle DR.

[0046] Next, we will consider the conditions for preventing the propeller guard 610 from protruding radially outward beyond the connecting member 30 when the propeller guard 610 of the unmanned aerial vehicle DR is approximately circular in plan view and when it is approximately polygonal in plan view.

[0047] 7, symbol O is the central axis of neck 510 of manhole 500, and symbol C is the central axis of propeller guard 610. Parameters R, R', r, X, and G in the figure are the outer diameter (radius) of propeller guard 610, the inner diameter (radius) of neck 510, the outer diameter (radius) of connecting member 30, the distance between central axis O of neck 510 and central axis C of propeller guard 610, and the distance between the outer edge of propeller guard 610 and the inner surface of neck 510, respectively. Note that the cross-sectional shape of connecting member 30 is assumed to be a circle that is considered to minimize the frictional force with propeller guard 610.

[0048] Using the law of cosines, the angle α in FIG.

number

[0049] Moreover, it is clear from FIG. 7 that the following formula (2) holds true.

number

[0050] Here, in order for the propeller guard 610 to not come into contact with the cylindrical wall portion 511, the following formula (3) must be satisfied.

number

[0051] The condition for preventing the propeller guard 610 from coming into contact with the cylindrical wall portion 511, obtained by using the above formulas (1) to (3), can be expressed by the following formula (4).

number

[0052] In formula (4), R and R' are already determined, so by determining either the radius r of the connecting member 30 or the arrangement angle θ, it is possible to design a flight support device 200 for the unmanned aerial vehicle DR that satisfies formula (4).

[0053] Here, if the radius r of the connecting member 30 is set large, the arrangement angle θ of the connecting member 30 can be increased, and the number of connecting members 30 used in the flight support device 200 of the unmanned aerial vehicle DR can be reduced. Therefore, the manufacturing cost of the flight support device 200 of the unmanned aerial vehicle DR can be reduced, and the weight can be reduced to facilitate portability. However, since the outer diameters of the ground opening guide member 10 and the body opening guide member 20 become smaller, the space in which the unmanned aerial vehicle DR can fly becomes narrower.

[0054] On the other hand, if the radius r of the connecting member 30 is set to be small, although the number of connecting members 30 increases, a larger flight space for the unmanned aerial vehicle DR can be secured, so that even an unmanned aerial vehicle DR with a relatively large outer diameter of the propeller guard 610 can fly inside the manhole 500.

[0055] Next, in the case where the propeller guard 610 has a regular polygonal shape, the condition for preventing the propeller guard 610 from coming into contact with the cylindrical wall portion 511 of the neck portion 510 of the manhole 500 will be considered using the model shown in FIG.

[0056] In this case as well, similarly to the case of FIG. 7, the flight support device 200 of the unmanned aerial vehicle DR can be designed so as to satisfy the following mathematical expression (5).

number

[0057] Here, if the radius r of the connecting member 30 is set large, the number of connecting members 30 can be reduced. Therefore, the manufacturing cost of the flight support device 200 for the unmanned aerial vehicle DR can be reduced, and the weight can be reduced to facilitate portability. However, since the outer diameters of the ground opening guide member 10 and the body opening guide member 20 become smaller, the space in which the unmanned aerial vehicle DR can fly becomes narrower.

[0058] On the other hand, if the radius r of the connecting member 30 is set to be small, although the number of connecting members 30 increases, a larger flight space for the unmanned aerial vehicle DR can be secured, so that even an unmanned aerial vehicle DR with a relatively large outer diameter of the propeller guard 610 can fly inside the manhole 500.

[0059] As described above, in this embodiment, the ground opening guide member 10 is configured to engage with a plurality of bars (square bars 140) that are spanned across the ground opening 510a at the upper end of the neck 510. By adopting such a configuration, even if the diameter of the ground opening guide member 10 is smaller than the inner diameter of the neck 510, the flight support device 200 of the unmanned aerial vehicle DR can be installed so that the lower surface of the outer edge of the ground opening guide member 10 abuts against the upper surface of the square bars 140.

[0060] Furthermore, in this embodiment, the multiple connecting members 30 are configured to be disposed radially inward of the neck portion 510 relative to the step 512 provided on the inner surface of the neck portion 510, at circumferential positions corresponding to the step 512. By adopting such a configuration, the propeller guard 610 of the unmanned aerial vehicle DR is likely to come into contact only with connecting members 30 that have a small frictional force upon contact, and therefore it is possible to prevent a large frictional force from acting on the propeller guard 610 and causing the unmanned aerial vehicle DR to crash.

[0061] Although the present disclosure has been described based on the drawings and embodiments, it should be noted that those skilled in the art can easily make various modifications and corrections based on the present disclosure. Therefore, it should be noted that these modifications and corrections are included in the scope of the present invention. For example, the functions included in each component can be rearranged so as not to cause logical inconsistencies, and multiple components can be combined into one or divided.

[0062] For example, in the second embodiment, an approximately circular shape is adopted as the shape of the ground opening guide member 10 and the body opening guide member 20, but this is not limited to this form, and for example, the shape may be such that it avoids only the area of ​​step 512 in a planar view, thereby ensuring a larger flight space for the unmanned aerial vehicle DR. [Explanation of symbols]

[0063] 10 Ground opening guide member 20 Structure opening guide member 30 Connecting members 31 Wide Spacing Section 100,200 Unmanned Aerial Vehicle Flight Support Equipment 140 Square bar (bar) 500 Manholes 510 Neck 511 Cylinder wall 512 steps 514 Lid holder member 520 Body part 520a Body opening 530 Pipeline 605 Main body 608 Propeller section 610 Propeller Guard 620 Fixed arm part C Propeller guard center axis O Neck central axis

Claims

1. A flight support device for an unmanned aerial vehicle in a manhole having a body portion forming an underground space and a neck portion having a horizontal width narrower than that of the body portion, the neck portion connecting a body opening provided at an upper portion of the body portion to the ground, an annular ground opening guide member that engages with the ground opening at the upper end of the neck; a ring-shaped body opening guide member disposed in the body opening; a plurality of connecting members extending in a substantially vertical direction and arranged in a circumferential direction of the neck portion, the connecting members connecting the ground opening guide member and the frame opening guide member; Equipped with The ground opening guide member is engaged with a plurality of rods spanning the ground opening at the upper end of the neck, providing a flight support device for an unmanned aerial vehicle.

2. The flight support device for an unmanned aerial vehicle as described in claim 1, wherein the multiple connecting members are arranged radially inward of the neck at circumferential positions corresponding to a step provided on the inner surface of the neck, the step being located at the radially inward position of the neck.

3. The flight support device for an unmanned aerial vehicle according to claim 1 or 2, wherein the body opening guide member abuts against an inner surface of the body opening.

4. 4. A flight support device for an unmanned aerial vehicle as described in any one of claims 1 to 3, wherein each of the plurality of connecting members has an approximately cylindrical shape and is coated with fluororesin or made of aluminum.

5. 5. A flight support device for an unmanned aerial vehicle as described in any one of claims 1 to 4, wherein at least one of the ground opening guide member and the body opening guide member is provided with a light emitting unit.

Images