JP2022026839A - Pilotless aircraft - Google Patents

Abstract

To make flight performance and submersion performance compatible in a pilotless aircraft submersible in water.SOLUTION: This is solved by a submersible pilotless aircraft (10) individually provided with a rotor (50) having a horizontal rotary blade (51) for flight and provided with a thrust source (60) used for movement in water. Such a pilotless aircraft preferably has a plurality of the rotors and a plurality of the thrust sources. Furthermore, it is preferable that the thrust source be able to generate thrust in one direction and an opposite direction to it and that the horizontal rotary blade be able to pivot in a direction along a rotation center axis of the rotor.SELECTED DRAWING: Figure 1

Description

The present invention relates to unmanned aerial vehicle technology.

In recent years, the application of unmanned aerial vehicles to various industrial fields has been studied.

International Publication No. 2017/073300

Conventional unmanned underwater vehicles (UUVs) have had to be carried by ship or the like to the water area to be submerged and submerged, or to be navigated from the water's edge to the target water area. According to the invention of Patent Document 1, it is possible to carry an underwater camera, which is an unmanned diving machine, to a water area to be submerged by a multicopter, and make the multicopter stand by on the water surface to remotely control the underwater camera. With such a configuration, there is an advantage that the flight function and the diving function can be completely separated into the multicopter and the underwater camera, but there is a problem that it is difficult to improve the efficiency and miniaturization of the structure of the entire device. ..

In view of such a problem, an object to be solved by the present invention is to achieve both flight performance and diving performance of an unmanned aerial vehicle capable of diving underwater.

In order to solve the above problems, it is a gist that the submersible unmanned aerial vehicle of the present invention is separately provided with a rotor having horizontal rotors for flight and a thrust source used for movement in water.

The diameter and pitch of the propeller (horizontal rotary blade) of the rotor mounted on the unmanned aerial vehicle are designed so that the flight efficiency is the highest. Naturally, such a rotor is not suitable as a thrust source in water, and cannot exhibit the maneuverability in water as in the air. On the other hand, if the rotor is designed in consideration of being used as a thrust source during diving, the cruising time and stability during flight will be impaired. By equipping the unmanned aerial vehicle with a thrust source used for movement underwater in addition to the rotor for flight, it is possible to achieve both the flight performance and the diving performance of the unmanned aerial vehicle.

At this time, it is preferable that the unmanned aerial vehicle of the present invention has a plurality of the rotors and the plurality of thrust sources. By providing a plurality of thrust sources during diving, it is possible to control the attitude and propulsion direction of the aircraft underwater without separately providing a rudder. At this time, it is preferable that the unmanned aerial vehicle of the present invention has the same number of rotors and thrust sources. This makes it possible to control the attitude and propulsion direction of the aircraft underwater by applying the same principle as during flight. Further, the unmanned aerial vehicle of the present invention preferably has four rotors and four thrust sources. This makes it possible to control the attitude and propulsion direction of the aircraft underwater by applying the general quadcopter flight principle.

Further, it is preferable that the thrust source can generate thrust in one direction and the opposite direction. Unmanned aerial vehicles can use the rotor and gravity to lift and lower the aircraft relatively freely during its flight. On the other hand, since buoyancy is acting in water, the aircraft does not react as quickly as in the air even if the thrust source is stopped. By generating thrust in one direction and the opposite direction from the thrust source, it is possible to arbitrarily control the attitude of the aircraft even underwater.

Further, it is preferable that the horizontal rotary blade can turn in a direction along the rotation center line of the rotor. If both a flying rotor and a thrust source used for underwater movement are provided, the rotor will only hinder movement in water. Since the rotor propeller (horizontal rotary blade) can rotate in the direction along the rotation center line of the rotor, the propeller can freely rotate and rotate without resisting the resistance of water during diving. This reduces propulsion resistance during diving.

Further, the thrust source is preferably a screw propeller. By providing a thrust source optimized for movement in water, it is possible to move the aircraft smoothly in water.

Further, the unmanned aerial vehicle of the present invention has a body portion which is a central portion of the airframe and a plurality of arms extending from the body portion, and each of the arms has these arms based on the attitude during flight. A convex portion protruding upward or downward from the convex portion may be provided, and the screw propeller may be arranged at the tip end portion of each of the convex portions. By providing a conical convex portion from each arm toward the propulsion direction, the stability of the posture during propulsion is enhanced. At this time, the rotor may be arranged at or near the rear end of each of the convex portions.

Further, it is preferable that each arm is a plate-shaped member arranged so that the plate surface faces the front-back or the left-right direction when the axial direction of each screw propeller is the vertical direction. As a result, the arm acts as a fin and can stabilize the posture during underwater propulsion.

Further, the unmanned aerial vehicle of the present invention preferably has a communication device that floats on the surface of the water when diving. When operating an underwater aircraft by wireless communication, for example, electromagnetic waves are significantly attenuated in conductors such as water, so even if the frequency of electromagnetic waves is lowered, communication can only be performed at a distance of several meters at most. By floating a communication device on the surface of the water and connecting the communication device to the unmanned aerial vehicle underwater with, for example, a signal line or communicating with light or ultrasonic waves, the unmanned aerial vehicle underwater can be freely operated from the water. ..

As described above, according to the present invention, it is possible to achieve both flight performance and diving performance of an unmanned aerial vehicle capable of diving underwater.

It is a perspective view which shows the appearance of the multicopter which concerns on embodiment. It is a perspective view which shows the state of a multicopter at the time of a dive. It is a side view (a) and a partially enlarged view (b) which shows the state of the turning of a propeller when a multicopter moves in water. It is a block diagram which shows the functional composition of a multicopter at the time of a flight. It is a block diagram which shows the functional composition of a multicopter at the time of a dive. It is a schematic diagram which shows an example of the communication method with the water at the time of diving of a multicopter. It is explanatory drawing of the levitation assist function of a multicopter by a screw propeller. It is a perspective view which shows the other embodiment of the unmanned aerial vehicle of this invention.

Hereinafter, embodiments of the present invention will be described. The embodiments listed below are examples of a multicopter 10 which is an unmanned aerial vehicle capable of not only flying in the air but also diving.

[Outline of configuration]
FIG. 1 is a perspective view showing the appearance of the multicopter 10 according to the present embodiment. FIG. 2 is a perspective view showing the state of the multicopter 10 during diving. In the following description, "up and down" and "vertical" are directions parallel to the Z axis of the coordinate axes drawn in each figure, with the Z1 side as the top and the Z2 side as the bottom. Further, "front and back", "left and right" and "side" mean directions orthogonal to the Z-axis direction. Note that the "up and down" here is not an absolute up and down along the vertical line (direction of gravity), but merely determines the upper and lower sides of the aircraft for convenience of explanation. The same applies to "vertical", "front and back", "left and right", and "sideways".

The multicopter 10 is a so-called quadcopter that moves in the air with four rotors 50. In addition to these rotors 50, the multicopter 10 includes four screw propellers 60 as thrust sources used for movement in water.

Normally, the rotor mounted on an unmanned aerial vehicle is designed with the diameter and pitch of its propeller so as to have the highest flight efficiency. Naturally, such a rotor is not suitable as a thrust source in water, and cannot exhibit the maneuverability in water as in the air. On the other hand, if the rotor is designed in consideration of being used as a thrust source during diving, the cruising time and stability during flight will be impaired. The multicopter 10 of the present embodiment is provided with a screw propeller 60 optimized for movement in water in addition to the rotor 50 for flight, thereby achieving both flight performance and diving performance.

The multicopter 10 of the present embodiment has a body portion 11 which is a central portion of the machine body, and four arms 12 extending from the body portion 11. The rotor 50 is arranged at the tip of each arm 12. Further, the tip of each arm 12 is provided with a convex portion 13 protruding downward in a conical shape. The screw propeller 60 is arranged at the tip of each convex portion 13.

The body portion 11 of the present embodiment is a vertically long, substantially spindle-shaped case body, and is formed so that the upper side is slightly thin and the lower side is thick. Each arm 12 extends laterally from the body portion 11 in a radial manner in a plan view. The arm 12 of this embodiment is a plate-shaped member arranged so that its plate surface faces sideways. As a result, the arm 12 also acts as a fin, and the posture during underwater propulsion can be further stabilized.

The rotor 50 has a propeller 51 which is a horizontal rotary blade, a motor (not shown) which is a drive source thereof, and a spinner 52 which covers the motor. The rotor 50 is arranged at the rear end of each convex portion 13, and the motor of the rotor 50 is housed in whole or a part thereof in each convex portion 13. In this embodiment, a waterproof motor is used for the motor itself, but for example, the convex portion 13 or the spinner 52 may be provided with a waterproof structure to prevent water from entering the accommodation space of the motor.

As mentioned above, the screw propeller 60 is arranged at the tip of each convex portion 13. In this embodiment, the stability of the posture during propulsion is enhanced by providing a conical convex portion from each arm 12 toward the main propulsion direction (Z2 direction in this embodiment) of the screw propeller 60.

By including a plurality of rotors 50 and a plurality of screw propellers 60, the multicopter 10 of the present embodiment can control the attitude and propulsion direction of the airframe in water without separately providing a rudder. Further, by providing four screw propellers 60, it is possible to control the attitude and propulsion direction of the aircraft underwater by applying the flight principle of a general quadcopter.

[Structure of rotor and screw propeller]
FIG. 3 is a side view (a) and a partially enlarged view (b) showing the state of the propeller 51 when the multicopter 10 moves in the water. Hereinafter, the structures of the propeller 51 and the screw propeller 60 of the rotor 50 will be described with reference to FIG.

The screw propeller 60 of this embodiment can generate thrust in the Z1 direction and the Z2 direction. The multicopter 10 in flight can raise and lower each part of the airframe relatively freely by using the rotor 50 and gravity. On the other hand, since buoyancy acts in water, the aircraft does not react as quickly as in the air even if the screw propeller 60 is stopped. Since the screw propeller 60 can generate thrust in one direction and the opposite direction (hereinafter referred to as "forward and reverse directions"), the posture of the multicopter 10 can be arbitrarily controlled even in water.

Further, the rotor 50 of the present embodiment includes a propeller 51 capable of turning in a direction along the rotation center line of the rotor 50 (in the present embodiment, the Z-axis direction). The propeller 51 is connected to the spinner 52 or a rotor hub (not shown) in the spinner 52 via a hinge. During flight, the rotor 50 rotates at high speed, so that the propeller 51 is automatically deployed by centrifugal force and kept in that position.

When a screw propeller 60 used for movement in water is provided separately from the rotor 50 for flight as in the multicopter 10, the rotor 50 only hinders movement in water. Since the propeller 51 of the rotor 50 can rotate in the direction along the rotation center line of the rotor 50, the propeller 51 can freely rotate and rotate without resisting the resistance of water when moving in water. This reduces propulsion resistance during diving.

[Functional configuration of multicopter]
FIG. 4 is a block diagram showing a functional configuration of the multicopter 10 during flight. FIG. 5 is a block diagram showing a functional configuration of the multicopter 10 during diving. FIG. 6 is a schematic diagram showing an example of a method of communicating with the water when the multicopter 10 is diving.

As shown in FIG. 4, the functions of the multicopter 10 during flight include a flight controller FC which is a control unit, a plurality of rotors 50, a communication device 72 which communicates with an operator (operator terminal 71), and electric power to these. It consists of a battery (not shown) that supplies power.

The flight controller FC has a control device 20 which is a microcontroller. The control device 20 is not limited to a single microcontroller, but may be a combination with a so-called companion computer. In addition, it is also conceivable to configure the control device 20 with, for example, an FPGA (field-programmable gate array) or an ASIC (Application Specific Integrated Circuit).

The flight controller FC further has a flight control sensor group S1 including an IMU 21 (Inertial Measurement Unit), a GPS receiver 22, a pressure sensor 23, and an electronic compass 24, which are connected to the control device 20. Has been done.

The IMU 21 is a sensor that detects the inclination of the multicopter 10, and is mainly composed of a 3-axis acceleration sensor and a 3-axis angular velocity sensor. The barometric pressure sensor 23 is an altitude sensor that obtains the altitude above sea level (elevation) of the multicopter 10 from the detected barometric pressure value. The electronic compass 24 is a sensor that detects the azimuth angle of the heading (nose) of the flight controller FC, and is mainly composed of a three-axis geomagnetic sensor. The GPS receiver 22 is, to be exact, a receiver of a navigation satellite system (NSS). The GPS receiver 22 acquires the current latitude and longitude value from the Global Navigation Satellite System (GNSS) or the Regional Navigational Satellite System (RNSS).

The flight control sensor group S acquires the position information of the aircraft including the latitude and longitude, altitude, and the azimuth angle of the nose in addition to the tilt and rotation of the aircraft by the flight control sensor group S.

The control device 20 has a flight control program FS, which is a program for controlling the attitude and basic flight operations of the multicopter 10 during flight. The flight control program FS adjusts the rotation speed of each rotor 50 based on the information acquired from the flight control sensor group S1, and flies the multicopter 10 while correcting the disturbance of the attitude and position of the aircraft.

The control device 20 further has an autonomous flight program AF, which is a program for autonomously flying the multicopter 10. Then, in the control device 20, a flight plan FP, which is a parameter in which the latitude and longitude of the course on which the multicopter 10 is flown, the altitude and the speed during flight, and the like are specified, is registered. The autonomous flight program AF autonomously flies the multicopter 10 according to the flight plan FP, with instructions from the operator terminal 71 and other systems, a predetermined time, and the like as starting conditions.

In addition, there are no particular restrictions on the devices and equipment mounted on the multicopter 10, such as general visible light cameras, dark vision cameras, depth cameras, LiDAR (Light Detection And Ranging), millimeter wave radars, microphones and speakers, and so on. It may be equipped with a parachute, a flash light, a warning light, an alarm / buzzer, or the like. On the contrary, for example, some or all of the sensors may be omitted from the flight control sensor group S1, or only manual control may be supported without the autonomous flight function.

The communication device 72 of the multicopter 10 and the operator terminal 71 are not limited as long as they can transmit and receive control signals and data, regardless of their specific communication method, protocol, line used, or the like. For example, by connecting the operator terminal 71 and the multicopter 10 through a mobile phone communication network such as 3G, LTE (Long Term Evolution), WiMAX (Worldwide Interoperability for Microwave Access), or 5G, the operator can use the mobile phone communication network. The multicopter 10 can be accessed from anywhere within the service area. If the range of movement of the multicopter 10 extends beyond the service area of the mobile phone communication network, such as offshore or mountainous areas, multi-satellite communication modules such as Iridium (registered trademark) and Inmarsat (registered trademark) are used. By mounting it on the copter 10, it is possible to maintain communication with the multicopter 10 even outside the service area of the mobile phone communication network. In addition, an access point may be installed in advance in the moving range of the multicopter 10, and communication may be performed with the multicopter 10 via the access point.

As shown in FIG. 5, the function of the multicopter 10 during diving is to supply electric power to a diving controller DC which is a control unit, a plurality of screw propellers 60, a communication device 72 which communicates with an operator terminal 71, and these. It consists of a battery (not shown). In addition, an external device according to the purpose of diving of the multicopter 10 may be separately mounted.

The diving controller DC has a control device 30 which is a microcontroller. The control device 30 is not limited to a single microcontroller, but may be a combination with a so-called companion computer. In addition, it is also conceivable to configure the control device 30 with, for example, FPGA or ASIC.

The diving controller DC further includes a diving control sensor group S2 including an IMU 31, an ultrasonic sensor 32, a water pressure sensor 33, a camera 34, and a floodlight 35 for the camera 34, which are connected to the control device 30. ..

The IMU 31 is a sensor that detects the inclination of the multicopter 10 in water, and is mainly composed of a 3-axis acceleration sensor and a 3-axis angular velocity sensor. The IMU21 of the flight control sensor group S1 can also be used instead of the IMU31. The water pressure sensor 33 is a sensor that obtains the water depth of the multicopter 10 from the detected pressure value. For example, by arranging the water pressure sensor 33 at the tip of each arm 12, it is possible to detect a change in the posture of the multicopter 10 in water. The ultrasonic sensor 32 and the camera 34 are sensors that detect the distance between the multicopter 10 and its peripheral objects in water.

The diving controller DC acquires the position information of the aircraft including the tilt and rotation of the aircraft, the relative position with the surrounding objects in the water, and the direction of the nose by the diving control sensor group S2. The camera 34 of this embodiment is used as a means for detecting a change in the position of the multicopter 10 in water and a distance from a peripheral object by image recognition, and transfers an underwater photographed image / video to an operator terminal 71. It can also be used as a camera. However, it is desirable to have a camera for position detection underwater and a camera for underwater photography separately.

The control device 30 has a diving control program DS, which is a program for controlling the attitude and basic navigation operation of the multicopter 10 during diving. The diving control program DS adjusts the rotation speed and rotation direction of each screw propeller 60 based on the information acquired from the diving control sensor group S2, and navigates the multicopter 10 while correcting the disturbance of the attitude and position of the aircraft. ..

The control device 30 further has an autonomous diving program AD, which is a program for autonomously navigating the multicopter 10 in water. A diving plan DP, which is a parameter in which the route for autonomously navigating the multicopter 10 and the water depth, speed, and the like are registered in the control device 30, is registered. The autonomous diving program AD autonomously navigates the multicopter 10 according to the diving plan DP, with instructions from the operator terminal 71 and other systems, a predetermined time, and the like as starting conditions.

As described above, the multicopter 10 of this embodiment has an advanced diving control function, but for example, some or all of the sensors may be omitted from the diving control sensor group S2, or only manual control may be performed without having an autonomous navigation function. May correspond to.

Further, as shown in FIG. 6, the multicopter 10 of this embodiment has a buoy 90 that floats on the water surface during diving. A known automatic expansion mechanism can be used as a mechanism for expanding the buoy 90 at the time of landing. For example, a part that dissolves in water is used in the lock mechanism of a gas cylinder filled with liquefied gas (carbon dioxide gas or a mixed gas of carbon dioxide gas and nitrogen gas), and the lock mechanism is released when the part dissolves by landing. There is a structure in which the bag-shaped body is filled with gas, and a structure in which the lock mechanism of the gas cylinder is electronically released by using a sensor for detecting water wetting.

In this embodiment, the multicopter 10 and the buoy 90 on the water are connected by a signal line 91. Further, a communication device 72 is arranged in the buoy 90, and the operator terminal 71 can communicate with the multicopter 10 via the communication device 72 on the water. A winch (not shown) is also mounted on the buoy 90 or the multicopter 10, and the length of the signal line 91 is automatically or manually adjusted.

Electromagnetic waves are significantly attenuated in conductors such as water. Therefore, when operating an underwater aircraft by wireless communication, even if the frequency of electromagnetic waves is lowered, communication can be performed only at a distance of several meters at most. In this embodiment, by floating the buoy 90 and the communication device 72 on the water, the underwater multicopter 10 can be remotely controlled without considering the attenuation of the electromagnetic wave due to the water. On the contrary, if the multicopter 10 is submerged within the range where the radio wave from the water can reach, the multicopter 10 may be directly operated by wireless communication. Alternatively, if the operator is near the area where the multicopter 10 is submerged, it is conceivable to directly connect the operator terminal 71 and the multicopter 10 with a signal line. Even in this case, since the multicopter 10 can also fly, the multicopter 10 can be quickly moved from the position of the operator to the target diving spot and dived.

The communication between the water communication device 72 and the underwater multicopter 10 is not limited to the wired connection by the signal line 91, and it is also possible to transmit and receive signals using, for example, light or ultrasonic waves as a medium. When communicating the buoy 90 (communication device 72) and the underwater multicopter 10 in a non-contact manner (non-wired), the buoy and the communication device during diving may be floated in advance around the diving spot.

Further, not only the communication device 72 but also the GPS receiver 22 is arranged in the buoy 90 of the present embodiment, and the multicopter 10 can acquire the latitude and longitude of the buoy 90 on the water. This makes it possible to specify a rough latitude and longitude at the current position in the water with reference to the latitude and longitude of the buoy 90. Further, if the relative position with the buoy 90 is grasped by, for example, a camera 34, an ultrasonic sensor 32, or another sensor, it is possible to specify a more accurate latitude and longitude in water.

[Floating assistance function]
FIG. 7 is an explanatory diagram of the levitation assist function of the multicopter 10 by the screw propeller 60.

As described above, in the multicopter 10 of the present embodiment, the screw propeller 60 is arranged at the tip of each convex portion 13, and the rotor 50 is arranged at the rear end of each convex portion 13. That is, the rotor 50 is arranged on the upper side (Z1 side), and the screw propeller 60 is arranged on the lower side (Z2 side). The screw propeller 60 can generate thrust in the forward and reverse directions.

When the multicopter 10 finishes diving and moves from the water to the air, the water surface sticks to the body of the multicopter 10 and the water separation of the multicopter 10 is hindered. Especially in an environment where the water surface is not stationary, such as the sea surface, the multicopter 10 may not be smoothly peeled off from the water surface. With the above configuration, the multicopter 10 of this embodiment can push up the machine body not only by the lift of the rotor 50 but also by the screw propeller 60 under the water surface at the time of water separation. As a result, the multicopter 10 can be smoothly separated from the water.

[Other embodiments]
Hereinafter, other embodiments of the unmanned aerial vehicle of the present invention will be described. FIG. 8 is a perspective view of the multicopter 10b, which is an example of another embodiment. In the following description, the same and similar configurations as each configuration of the multicopter 10 will be designated by the same reference numerals as those in the previous embodiment, and the description thereof will be omitted.

In the multicopter 10 of the previous embodiment, the screw propeller 60 is arranged at the tip of each convex portion 13, but in the multicopter 10b of the present embodiment, the screw propeller 60b is located at the lower end (Z2 side end portion) of the body portion 11. Only one is provided. The screw propeller 60b is also a thrust source capable of generating thrust in the forward and reverse directions. Each arm 12 of the multicopter 10b is provided with a rudder 14 for controlling the propulsion direction of the aircraft in water, and the arm 12 of the multicopter 10b also functions as a so-called + rudder / X rudder. .. As a result, the multicopter 10b can freely move in the water with only one screw propeller 60b without using a plurality of screw propellers. It is also possible to replace the rudder 14 by appropriately driving the four rotors 50 and adjusting their propulsion resistance individually.

The rotor 50 of the multicopter 10b also has a propeller 51 that can turn in a direction along the rotation center line of the rotor 50 as in the previous embodiment. If the propulsion resistance of the propeller 51 in water is acceptable, or if the rotor 50 is used in place of the rudder 14 as described above, the propeller 51 may be fixed in a non-swivelable manner.

The number of underwater thrust sources of the present invention is not limited to one or four. For example, 3, 6, or 8 thrust sources may be provided as long as the desired operation is possible in water. Further, the form of the underwater thrust source is not limited to the screw propeller, and may be, for example, a water jet propulsion device as long as it can generate thrust in a specific direction in water. Further, the underwater thrust source does not necessarily have to be able to generate thrust in the forward and reverse directions, and may generate thrust in only one direction depending on the type of motion required and the control accuracy.

Further, the number of rotors 50 of the present invention is not limited to four. For example, the rotor 50 may be a tricopter type with three units, a hexacopter type with six units, an octacopter type unmanned aerial vehicle with eight units, or a helicopter type with one main rotor and one tail rotor. good.

Although the embodiments of the present invention have been described above, the scope of the present invention is not limited to this, and various modifications can be made without departing from the gist of the invention.

10, 10b: Multicopter (unmanned aircraft), 11: Body, 12: Arm, 13: Convex, 14: Steering, FC: Flight controller, 20: Control device, FS: Flight control program, AF: Autonomous flight program , FP: Flight plan, S1: Flight control sensor group, 21: IMU, 22: GPS receiver, 23: Pressure sensor, 24: Electronic compass, 50: Rotor, 51: Propeller, 52: Spinner, DC: Diving controller, 30: Control device, DS: Diving control program, AD: Autonomous diving program, DP: Diving plan, S2: Diving control sensor group, 31: IMU, 32: Ultrasonic sensor, 33: Water pressure sensor, 34: Camera, 35: Floodlight, 60, 60b: Screw propeller (thrust source), 71: Operator terminal, 72: Communication device, 90: Buoy, 91: Signal line

Claims (11)

With a rotor with horizontal rotors for flight,
An unmanned aerial vehicle that can be submerged with a thrust source used for movement in the water. The unmanned aerial vehicle according to claim 1, which has a plurality of the rotors and the plurality of thrust sources. The unmanned aerial vehicle according to claim 2, wherein the rotor and the thrust source are provided in the same number. The unmanned aerial vehicle according to claim 3, which has four rotors and four thrust sources. The unmanned aerial vehicle according to any one of claims 1 to 4, wherein the thrust source can generate thrust in one direction and the opposite direction. The unmanned aerial vehicle according to any one of claims 1 to 5, wherein the horizontal rotary blade can turn in a direction along the rotation center line of the rotor. The unmanned aerial vehicle according to any one of claims 1 to 6, wherein the thrust source is a screw propeller. The fuselage, which is the center of the aircraft,
It has a plurality of arms extending from the body and has a plurality of arms.
Each of the arms is provided with a convex portion protruding upward or downward from these arms in a conical shape with reference to the attitude during flight.
The unmanned aerial vehicle according to claim 7, wherein the screw propeller is arranged at the tip of each convex portion. The unmanned aerial vehicle according to claim 8, wherein the rotor is arranged at the rear end of each of the convex portions or in the vicinity thereof. The unmanned aerial vehicle according to claim 8 or 9, wherein each arm is a plate-shaped member arranged so that the plate surface faces front-back or left-right when the axial direction of each screw propeller is set in the vertical direction. .. The unmanned aerial vehicle according to any one of claims 1 to 10, wherein the unmanned aerial vehicle has a communication device that floats on the surface of the water when diving.

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