Unmanned aerial vehicle with Faraday cage

Abstract

In an unmanned aerial vehicle 1 with a Faraday cage, the Faraday cage 11 is configured to include a conductor in which a first coil 11A formed from a conductor wound in a predetermined direction and a second coil 11B formed from a conductor wound in the opposite direction to the predetermined direction are connected in series or parallel.

Description

[Technical Field]

[0001] This disclosure relates to an unmanned aerial vehicle equipped with a Faraday cage. [Background technology]

[0002] Non-Patent Document 1 discloses a technology for detecting lightning strikes and safely guiding the detected lightning to the ground by flying a drone equipped with a lightning rod and a guide wire with one end grounded. Non-Patent Document 2 discloses a technology for protecting a drone from lightning strikes by equipping the drone with a spherical Faraday cage. These technologies allow for guiding lightning strikes to a safe or desired location (e.g., an electric vehicle, a battery) while protecting the drone from lightning strikes. [Prior art documents] [Non-patent literature]

[0003] [Non-Patent Document 1] “E03 Lightning Control and Charging Technology”, Nippon Telegraph and Telephone Corporation, NTT R&D Forum 2020 Connect, 2020 [Non-Patent Document 2] Masuda, et al., "Basic Study on Improving Lightning Resistance of Drones," IEICE University, B-4-6, 2021, p.179. [Overview of the project] [Problems that the invention aims to solve]

[0004] In order to use drones to induce lightning (hereinafter referred to as "lightning induction"), the drone used for induction must be able to withstand lightning surges. However, the shape of the Faraday cage surrounding the drone may change due to the electromagnetic force caused by the lightning surge, which could cause the drone to crash.

[0005] For example, if a spherical Faraday cage is struck by lightning at its apex, and lightning surges flow simultaneously downward in parallel through each of the four vertical conductors A to D, then the electromagnetic force of conductor A, considering the combined magnetic field of the other conductors B to D and the direction of the current in conductor A, becomes an attractive force towards the inside of the sphere according to Fleming's law.

[0006] Therefore, if a large current such as a lightning surge flows, the conductors that make up the Faraday cage may bend inward towards the sphere, and the bent conductors may come into contact with the drone, potentially cutting the propellers and causing the drone to crash.

[0007] This disclosure is made in view of the above circumstances, and the purpose of this disclosure is to provide a technology that can reduce the crash risk of unmanned aerial vehicles equipped with a Faraday cage. [Means for solving the problem]

[0008] An unmanned aerial vehicle with a Faraday cage according to one aspect of the present disclosure is configured such that the Faraday cage includes a conductor connected in series or in parallel to a first coil made of a conductor wound in a predetermined direction and a second coil made of a conductor wound in the opposite direction to the predetermined direction. [Effects of the Invention]

[0009] According to this disclosure, we can provide technology that can mitigate the crash risk of unmanned aerial vehicles equipped with Faraday cages. [Brief explanation of the drawing]

[0010] [Figure 1] Figure 1 shows the configuration of a drone with a Faraday cage according to the first embodiment. [Figure 2] Figure 2 shows the magnetic field generated in each coil connected in series. [Figure 3] Figure 3 shows the configuration of a drone with a Faraday cage according to the second embodiment. [Figure 4]FIG. 4 is a diagram showing magnetic fields generated in each of the coils connected in parallel.

Embodiments for Carrying Out the Invention

[0011] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the description of the drawings, the same reference numerals are given to the same parts and the description thereof will be omitted.

[0012] [First Embodiment] FIG. 1 is a diagram showing the configuration of a drone 1 with a Faraday cage according to the first embodiment.

[0013] The drone 1 with a Faraday cage includes a spherical Faraday cage 11, and a drone 12 fixedly connected to a part of the Faraday cage 11 and disposed inside the Faraday cage 11.

[0014] The Faraday cage 11 is a conductor cage for protecting the drone from lightning strikes and has the effect of shielding the internal space from an external electric field. The Faraday cage 11 is formed by combining a plurality of conductors in the vertical and horizontal directions and is formed in a spherical shape as a whole. The overall shape of the Faraday cage 11 may also be a rectangular parallelepiped, a hexagonal prism, a cylinder, or the like.

[0015] P In the present disclosure, the conductors, which are components of the Faraday cage 11, are improved. Specifically, the Faraday cage 11 is configured using two types of conductor coils with opposite winding directions. By canceling (reducing, offsetting) the magnetic fields generated in the two types of conductor coils with each other's magnetic fields, the electromagnetic force (the attractive force toward the inside of the sphere) during lightning strikes is suppressed.

[0016] More specifically, as shown in FIG. 1, the Faraday cage 11 according to the first embodiment is configured by connecting in series a first coil 11A made of a conductor wound in a predetermined direction (a predetermined rotation direction) and a second coil 11B made of a conductor wound in a direction opposite to the predetermined direction (an opposite rotation direction).

[0017] In FIG. 1, among the plurality of conductors in the vertical and horizontal directions that constitute the Faraday cage 11, the plurality of vertical conductors are each constituted by conductors in which the second coil 11B, the first coil 11A, the first coil 11A, and the second coil 11B are connected in series in that order.

[0018] In the first coil 11A and the second coil 11B connected in series, magnetic fields H

[0021] , , , H B are generated. For example, it is assumed that a current is input from the left side of the paper surface of FIG. 2 and flows to the right side of the paper surface through the second coil 11B and the first coil 11A connected in series in that order. It is assumed that the left second coil 11B is wound in a clockwise direction as viewed from the left side of the paper surface. It is assumed that the right first coil 11A is wound in a counterclockwise direction as viewed from the left side of the paper surface.

[0019] At this time, a current i B flows through the second coil 11B in a clockwise direction as viewed from the left side of the paper surface. In this case, the direction of the internal magnetic field H B(1) is from left to right. The direction of the external magnetic field H B(2) is the direction that returns from the output side of the current to the input side of the current via the outside. On the other hand, a current i A flows through the first coil 11A in a counterclockwise direction as viewed from the left side of the paper surface. In this case, the direction of the internal magnetic field H A(1) is from right to left. The direction of the external magnetic field H A(2) is the direction that returns from the input side of the current to the output side of the current via the outside.

[0020] Thus, the directions of the magnetic fields H A , H B generated in the first coil 11A and the second coil 11B connected in series are opposite to each other both in the internal magnetic field and the external magnetic field. Therefore, the magnetic field of one coil is reduced by the magnetic field of the other coil. Since each magnetic field generated in the plurality of vertical conductors is reduced, the combined magnetic field due to lightning surges is reduced both in the internal magnetic field and the external magnetic field, and the electromagnetic force (the attractive force toward the inside of the sphere) at the time of lightning strike can be reduced.

[0021] As a result, the shape of the Faraday cage 11 can be maintained in its original form, allowing the drone to fly stably even during lightning strikes. In addition, the first coil 11A and the second coil 11B also function as springs, and the elasticity of these springs reduces the impact caused by thermal expansion of the air during lightning strikes, enabling stable flight of the drone.

[0022] Furthermore, this method is not limited to vertical conductors; horizontal conductors may also be configured similarly. It is also preferable that the number of turns of the conductors in the first coil 11A and the second coil 11B are the same. This ensures that the magnitudes of the magnetic fields generated in each are equal, allowing them to cancel each other out.

[0023] Drone 12 is an example of an unmanned aerial vehicle.

[0024] As described above, according to the first embodiment, the conductor of the Faraday cage 11 is configured by connecting in series a first coil 11A, which is made of a conductor wound in a predetermined direction, and a second coil 11B, which is made of a conductor wound in the opposite direction to the predetermined direction. This reduces the risk of the drone crashing and enables stable flight of the drone.

[0025] [Second Embodiment] Figure 3 shows the configuration of the Faraday cage-equipped drone 1 according to the second embodiment.

[0026] In the second embodiment, the first coil 11A and the second coil 11B are connected in parallel. For example, the multiple vertical conductors constituting the Faraday cage 11 are each composed of a conductor formed by connecting four first coils 11A in series, a conductor formed by connecting four second coils 11B in series, and a conductor formed by connecting these in parallel. Furthermore, the four first coils 11A and the four second coils 11B are arranged in adjacent positions.

[0027] The magnetic fields H generated when the first coil 11A and the second coil 11B are connected in parallel. A H BFigure 4 shows the situation. Magnetic fields H are generated in the first coil 11A and the second coil 11B, which are connected in parallel. A H B The orientation of the internal and external magnetic fields is opposite to that of the series connection. Therefore, the same effects as in the first embodiment can be obtained.

[0028] As described above, according to the second embodiment, the conductor of the Faraday cage 11 is configured by connecting in parallel a first coil 11A, which is made of a conductor wound in a predetermined direction, and a second coil 11B, which is made of a conductor wound in the opposite direction to the predetermined direction. This reduces the risk of the drone crashing and enables stable flight of the drone.

[0029] [Other embodiments] It is also possible to combine the first embodiment and the second embodiment. [Explanation of symbols]

[0030] 1. Drone with Faraday Cage 11 Faraday Cage 11A First coil 11B Second coil 12 Drones

Claims

[Claim 1] In an unmanned aerial vehicle equipped with a Faraday cage, The aforementioned Faraday cage is An unmanned aerial vehicle with a Faraday cage, comprising a conductor comprising a first coil made of a conductor wound in a predetermined direction and a second coil made of a conductor wound in the opposite direction to the predetermined direction, connected in series or in parallel.

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