Unmanned aircraft

Abstract

An unmanned aircraft according to the present invention comprises: a plurality of rotors; an electric power source; and a power supply device that supplies external electric power from the electric power source to a work machine.

Description

unmanned aerial vehicle

[0001] The present disclosure relates to unmanned aerial vehicles.

[0002] An unmanned aerial vehicle (UAV) is an aircraft that cannot carry a person due to its structure and can fly by remote control or automatic pilot. Rotary-wing unmanned aerial vehicles are unmanned aerial vehicles that obtain lift using propellers that rotate around an axis, i.e., rotors. Small unmanned aerial vehicles equipped with multiple rotors (multi-rotor UAVs) are also called "drones," "multirotors," or "multicopters," and are widely used for applications such as aerial photography, surveying, logistics, and pesticide spraying.

[0003] Patent Document 1 describes an unmanned aerial vehicle (unmanned aerial vehicle) that changes its flight position in conjunction with the operation of agricultural machinery.

[0004] Japanese Patent Application Laid-Open No. 2022-104737

[0005] The maximum payload and flight time of unmanned aerial vehicles are insufficient for some applications, and further improvements are required.

[0006] The present disclosure provides unmanned aerial vehicles suitable for agricultural applications that allow for increased payload and / or flight time.

[0007] The present disclosure provides the solutions described in the following items.

[0008] [Item A1] An unmanned aerial vehicle having a plurality of rotors, comprising: a plurality of first rotors included in the plurality of rotors; at least one second rotor included in the plurality of rotors; a plurality of electric motors that respectively drive the plurality of first rotors; an internal combustion engine that drives the at least one second rotor; a battery that stores a first electric power; a power generation device that is driven by the internal combustion engine to generate a second electric power; a first power control device that controls charging and discharging of the battery; and a second power control device that controls power generation by the power generation device, wherein each of the plurality of electric motors receives at least one of the first electric power and the second electric power, and the first power control device controls the second power control device.

[0009] [Item A2] The unmanned aerial vehicle according to Item A1, wherein the first power control device controls the second power control device depending on the state of the battery.

[0010] [Item A3] The unmanned aerial vehicle according to Item A1, further comprising wiring connecting the electric motor to the power generation device and the battery, and the first power control device controlling the electrical connection between the wiring and the battery.

[0011] [Item A4] An unmanned aerial vehicle described in any one of Items A1 to A3, wherein the first power control device controls the second power control device to adjust the amount of power generation depending on the work content of the unmanned aerial vehicle.

[0012] [Item A5] The unmanned aerial vehicle described in any one of Items A1 to A3, wherein the first power control device controls the charging rate of the battery according to flight conditions including the flight altitude of the unmanned aerial vehicle.

[0013] [Item A6] The unmanned aerial vehicle described in any one of items A1 to A5, wherein the first power control device controls the charging rate of the battery depending on the distance from the unmanned aerial vehicle to a possible landing point.

[0014] [Item A7] The unmanned aerial vehicle according to any one of Items A1 to A3, including a control device that functions as the first power control device and the second power control device.

[0015] [Item B1] An unmanned aerial vehicle having a plurality of rotors, the unmanned aerial vehicle comprising: a power source; and a power supply device that supplies external power from the power source to a work machine.

[0016] [Item B2] An unmanned aerial vehicle as described in Item B1, comprising: a plurality of electric motors that respectively drive a plurality of first rotors included in the plurality of rotors; a first wiring that supplies power from the power source to each of the plurality of electric motors; and a second wiring that branches off from the first wiring and supplies the external power from the power source to the power supply device.

[0017] [Item B3] The unmanned aerial vehicle according to Item B2, wherein the power source includes a battery that stores the first power.

[0018] [Item B4] An unmanned aerial vehicle as described in Item B2 or 3, comprising: at least one second rotor included in the plurality of rotors; an internal combustion engine that drives the at least one second rotor; and a power generation device that is driven by the internal combustion engine to generate second electric power, wherein the power source includes the power generation device, and the power generation device is connected to the first wiring and the second wiring.

[0019] [Item B5] The unmanned aerial vehicle according to any one of items B1 to B4, wherein the work machine is an exchangeable implement that performs agricultural work on a field or crops in the field.

[0020] [Item B6] The unmanned aerial vehicle according to any one of Items B1 to B5, wherein the power supply device has a terminal for supplying power to the work machine and a terminal for communicating with the work machine.

[0021] [Item B7] An unmanned aerial vehicle as described in Item B6, further comprising a control device that controls the output of the external power from the power supply device, wherein the control device controls the supply of the external power in accordance with the current operating state or the planned operating state of the work machine obtained through the communication.

[0022] [Item B8] The unmanned aerial vehicle described in any one of Items B1 to B7, wherein the unmanned aerial vehicle is configured to fly while towing the work machine, and the power supply device and the work machine are electrically connected by a cable.

[0023] [Item C1] An unmanned aerial vehicle having a plurality of rotors, comprising: a plurality of first rotors included in the plurality of rotors; at least one second rotor included in the plurality of rotors; a plurality of electric motors that respectively drive the plurality of first rotors; an internal combustion engine that drives the at least one second rotor; a battery that stores a first electric power; a power generation device that is driven by the internal combustion engine to generate a second electric power; a control device that controls at least one of the operation of the internal combustion engine, the operation of the electric motor, charging and discharging of the battery, and power generation by the power generation device; and a power supply device that supplies at least a portion of the first electric power and the second electric power to a work machine as a third electric power, wherein the control device controls at least one of the operation of the internal combustion engine, the operation of the electric motor, charging and discharging of the battery, and power generation by the power generation device according to the content of a current operation or a content of a planned operation of the work machine.

[0024] [Item C2] The unmanned aerial vehicle according to Item C1, wherein the control device starts charging the battery before the start of the planned operation of the work machine, depending on the content of the planned operation of the work machine.

[0025] [Item C3] The unmanned aerial vehicle according to Item C2, wherein the control device adjusts the charging rate or the charging amount of the battery depending on the content of the operation.

[0026] [Item C4] The unmanned aerial vehicle according to Item C1 or C2, wherein the control device increases the amount of power generated by the power generation device before the start of the planned operation of the work machine, depending on the content of the planned operation of the work machine.

[0027] [Item C5] The unmanned aerial vehicle according to Item C4, wherein the control device adjusts the amount of power generation depending on the content of the operation.

[0028] [Item C6] The unmanned aerial vehicle described in any one of Items C1 to C5, wherein the control device has a first power control device that controls charging and discharging of the battery, and a second power control device that controls power generation by the power generation device.

[0029] [Item C7] The unmanned aerial vehicle according to any one of Items C1 to C6, wherein the control device acquires the content of the current operation or the content of the planned operation of the work machine from a work plan.

[0030] [Item C8] The unmanned aerial vehicle according to any one of Items C1 to C6, wherein the control device acquires the content of the current operation of the work machine or the content of the planned operation of the work machine from the work machine.

[0031] [Item C9] The unmanned aerial vehicle according to any one of Items C1 to C8, wherein the work machine is an interchangeable implement that performs agricultural work on a field or crops in the field.

[0032] [Item C10] The unmanned aerial vehicle according to any one of Items C1 to C9, wherein the power supply device has a terminal for supplying power to the work machine and a terminal for communicating with the work machine.

[0033] [Item C11] The unmanned aerial vehicle described in any one of Items C1 to C10, wherein the unmanned aerial vehicle is configured to fly while towing the work machine, and the power supply device and the work machine are electrically connected by a cable.

[0034] Embodiments of the unmanned aerial vehicle disclosed herein allow the generation and utilization of the electrical power required to rotate the electric motor to be adjusted according to flight conditions or tasks.

[0035] 1 is a block diagram schematically showing several examples of a rotary drive device that rotates rotors in an unmanned aerial vehicle having multiple rotors. FIG. 2 is a plan view schematically showing one basic configuration example of an unmanned aerial vehicle having multiple rotors. FIG. 3 is a side view schematically showing one basic configuration example of an unmanned aerial vehicle having multiple rotors. FIG. 4 is a plan view schematically showing another basic configuration example of an unmanned aerial vehicle having multiple rotors. FIG. 5 is a block diagram showing an example basic configuration of a battery-powered multicopter. FIG. 6 is a block diagram showing an example basic configuration of a series hybrid multicopter. FIG. 7 is a block diagram showing an example basic configuration of a parallel hybrid multicopter. FIG. 8 is a top view schematically showing a multicopter according to an embodiment of the present disclosure. FIG. 9 is a side view schematically showing a multicopter according to this embodiment. FIG. 10 is a block diagram showing an example system configuration of a multicopter according to this embodiment. FIG. 11 is a block diagram showing an example configuration of a battery management device according to this embodiment. FIG. 12 is a diagram for explaining an overview of an agricultural management system according to this embodiment. FIG. 13 is a diagram showing an example of a work plan for each agricultural work. FIG. 14 is a diagram showing an example of a setting screen displayed on a terminal device. 1 is a side view schematically showing the lower limit (first reference value) of the target range of the state of charge (SOC) when the flight altitude of the multicopter in this embodiment is h4, h3, h2, or h1. FIG. 2 is a graph schematically showing an example of the relationship between the flight altitude of the multicopter and the lower limit (first reference value) of the target range of the state of charge (SOC) in this embodiment. FIG. 3 is a flowchart showing an example of processing performed by the battery management device in this embodiment. FIG. 4 is a flowchart showing an example of the operation of an external power supply in this embodiment. FIG. 5 is a graph showing an example of the relationship between power consumption, power generation amount, and engine speed of a planned operation of a work machine in this embodiment. FIG. 6 is a block diagram schematically showing the connection state of a power supply device and a work machine in this embodiment. FIG. 7 is a block diagram showing an example of the hardware configuration of a control device in this embodiment. FIG. 8 is a diagram schematically showing an example of a communication network to which a multicopter is connected in this embodiment.

[0036] An unmanned aerial vehicle with multiple rotors includes a rotary drive unit that rotates the rotors (hereinafter sometimes referred to as "propellers"). Hereinafter, such an unmanned aerial vehicle will be referred to as a "multicopters."

[0037] There are various configurations of the rotary drive device provided in a multicopter. Fig. 1A is a block diagram schematically illustrating four examples of the rotary drive device 3 in the present disclosure.

[0038] The first rotation drive device 3A shown in FIG. 1A has a plurality of electric motors (hereinafter referred to as "motors") 14 that rotate a plurality of rotors 2, and a battery 52 that stores power to be supplied to each motor 14. The battery 52 is, for example, a secondary battery such as a polymer lithium-ion battery. Each rotor 2 is connected to the output shaft of the corresponding motor 14 and rotated by the motor 14. In order to increase the payload and / or flight time, it is necessary to increase the power storage capacity of the battery 52. ​​The power storage capacity of the battery 52 can be increased by increasing the size of the battery 52, but increasing the size of the battery 52 results in an increase in weight.

[0039] The second rotation drive device 3B shown in FIG. 1A includes a power transmission system 23 mechanically connected to the rotor 2 and an internal combustion engine 7a that provides driving force (torque) to the power transmission system 23. The power transmission system 23 includes mechanical components such as gears or belts, and transmits torque from the output shaft of the internal combustion engine 7a to the rotor 2. The internal combustion engine 7a can efficiently generate mechanical energy by burning fuel. Examples of the internal combustion engine 7a include a gasoline engine, a diesel engine, and a hydrogen engine. The number of internal combustion engines 7a included in the rotation drive device 3B is not limited to one.

[0040] The third rotary drive device 3C shown in FIG. 1A includes multiple motors 14, a power buffer 9 that stores power to be supplied to each motor 14, a power generator 8 such as an alternator that generates power, and an internal combustion engine 7a that provides mechanical energy for the power generator 8 to generate electricity. A typical example of the power buffer 9 is a battery such as a secondary battery, but it may also be a capacitor. In the third rotary drive device 3C, even if the power buffer 9 does not have a large storage capacity, the power generator 8 generates power using the driving force (mechanical energy) of the internal combustion engine 7a, thereby enabling an increase in payload and / or flight time. This type of drive is called a "series hybrid drive." The power generator 8 and internal combustion engine 7a in the series hybrid drive are called a "range extender" because they extend the flight distance of the multicopter.

[0041] 1A includes a plurality of motors 14, a power buffer 9 that stores power to be supplied to each motor 14, a power generator 8 such as an alternator that generates power, an internal combustion engine 7a that provides driving force for generating power to the power generator 8, and a power transmission system 23 that transmits the driving force generated by the internal combustion engine 7a to a rotor 2 to rotate the rotor 2. At least one rotor 2 of the plurality of rotors 2 is rotated by the internal combustion engine 7a, and the other rotors 2 are rotated by the motor 14. In the fourth rotary drive device 3D, the mechanical energy generated by the internal combustion engine 7a can also be used to rotate the rotor 2 without being converted into electric power, thereby improving energy utilization efficiency. This type of drive is called a "parallel hybrid drive."

[0042] Fig. 1B is a plan view schematically illustrating one basic configuration example of multicopter 10. The configuration example of Fig. 1B includes the first rotational drive device 3A shown in Fig. 1A as the rotational drive device 3. That is, the rotational drive device 3 (3A) in this example includes a motor 14 and a battery 52. ​​Fig. 1C is a side view schematically illustrating multicopter 10.

[0043] 1B and 1C includes a plurality of rotors 2, an airframe 4, and an airframe frame 5 that supports the rotors 2 and the airframe 4. The airframe frame 5 supports the airframe 4 at its center and rotatably supports the plurality of rotors 2 with a plurality of arms 5A extending outward from the center. A motor 14 that rotates the rotors 2 is provided near the tip of each arm 5A. The airframe 4 and the airframe frame 5 are sometimes collectively referred to as the "airframe 11."

[0044] 1B, the multicopter 10 is a quad-type multicopter (quadcopter) having four rotors 2. The rotors 2 located on one diagonal line rotate in the same direction (clockwise or counterclockwise), while the rotors 2 located on different diagonal lines rotate in opposite directions.

[0045] The main body 4 includes a control device 4a that controls the operation of devices and components mounted on the multicopter 10, a group of sensors 4b connected to the control device 4a, a communication device 4c connected to the control device 4a, and a battery 52.

[0046] The control device 4 a may include, for example, a flight control device such as a flight controller and a host computer (companion computer). The companion computer can perform advanced arithmetic processing such as image processing, obstacle detection, and obstacle avoidance based on the sensor data acquired by the sensor group 4 b.

[0047] The sensor group 4b may include an acceleration sensor, an angular velocity sensor, a geomagnetic sensor, a barometric pressure sensor, an altitude sensor, a temperature sensor, a flow rate sensor, an imaging device, a laser sensor, an ultrasonic sensor, an obstacle contact sensor, and a Global Navigation Satellite System (GNSS) receiver. The acceleration sensor and the angular velocity sensor may be mounted on the airframe main body 4 as components of an IMU (Inertial Measurement Unit). Examples of the laser sensor may include, for example, a laser range finder used to measure the distance to the ground, and a two-dimensional or three-dimensional light detection and ranging (LiDAR).

[0048] The communication device 4c may include a wireless communication module for transmitting and receiving signals via an antenna to a transmitter or ground station (Ground Control Station (GCS)) on the ground, a mobile communication module using a cellular communication network, etc. The communication device 4c may receive signals such as control commands transmitted from the ground and transmit sensor data such as image data acquired by the sensor group 4b as telemetry information. The communication device 4c may have a function for communicating between multicopters and a satellite communication function. The control device 4a can be connected to a computer on the cloud via the communication device 4c. Some or all of the functions of the companion computer may be performed by the computer on the cloud.

[0049] The battery 52 is a secondary battery that stores power by charging and supplies power to the motors 14 by discharging. The battery 52 and the multiple motors 14 operate to rotate the multiple rotors 2, making it possible to generate a desired thrust.

[0050] Each of the multiple rotors 2 generally has multiple blades with a fixed pitch angle and generates thrust by rotation. The pitch angle may be variable. The multiple rotors 2 do not all need to have the same diameter (propeller diameter); one or more rotors 2 may have a larger diameter than the other rotors 2. The thrust (static thrust) generated by a rotating rotor 2 is generally proportional to the cube of the rotor 2 diameter. Therefore, when rotors 2 with different diameters are included, the rotor 2 with a relatively larger diameter may be referred to as the "main rotor," and the rotor 2 with a relatively smaller diameter may be referred to as the "sub-rotor." Note that, regardless of the diameter, the configuration of the rotary drive device 3 may include a rotor 2 capable of generating a relatively larger thrust and a rotor 2 with a relatively smaller thrust. In this case, the rotor 2 capable of generating a relatively larger thrust may be referred to as the "main rotor," and the rotor 2 with a relatively smaller thrust may be referred to as the "sub-rotor." For example, the rotor 2 that generates a relatively large thrust per rotation may be referred to as the "main rotor," and the rotor 2 that generates a relatively small thrust per rotation may be referred to as the "sub-rotor." In one example, the main rotor may be positioned more inward than the sub-rotors. In other words, each rotor 2 may be positioned so that the distance from the center of the airframe to the rotation axis of each main rotor is shorter than the distance from the center of the airframe to the rotation axis of each sub-rotor.

[0051] In this example, the rotary drive device 3 includes a plurality of motors 14. As mentioned above, the rotary drive device 3 may include an internal combustion engine 7a.

[0052] FIG. 1D is a plan view schematically illustrating an example of the basic configuration of a multicopter 10 including a second rotational drive device 3B as the rotational drive device 3. In the example shown in FIG. 1D , an internal combustion engine 7a is supported by the airframe main body 4. In this example, the driving force generated by the internal combustion engine 7a is transmitted to multiple rotors 2 via multiple power transmission systems 23, causing each rotor 2 to rotate. The control device 4a can change the rotational speed of each rotor 2 by controlling each power transmission system 23. The rotational drive device 3B may include a mechanism for changing the pitch angle of each blade of the multiple rotors 2. In this case, the control device 4a may adjust the lift generated by each rotor 2 by controlling the mechanism to change the pitch angle of the blades.

[0053] In a "parallel hybrid drive" in which some of the multiple rotors 2 are rotated by the internal combustion engine 7a and the other rotors 2 are rotated by the motor 14, the internal combustion engine 7a and the battery 52 are supported on the aircraft body 4. At least one rotor 2 of the multiple rotors 2 is connected to the internal combustion engine 7a via the power transmission system 23, and the other rotors 2 are connected to the motor 14.

[0054] In such a parallel hybrid drive, the diameter of one or more rotors 2 rotated by the internal combustion engine 7a may be larger than the diameter of the other rotors 2 rotated by the motor 14. In other words, the internal combustion engine 7a may be used to rotate the main rotor, and the motor 14 may be used to rotate the sub-rotor. In such a case, the main rotor is primarily used to generate thrust, and the sub-rotor is used to generate thrust and for attitude control. The main rotor may also be called a "booster rotor," and the sub-rotor may also be called an "attitude control rotor."

[0055] In the case of a parallel hybrid drive, the internal combustion engine is used for both thrust generation and power generation. By selectively transmitting the driving force (torque) generated by the internal combustion engine to one or both of the rotor and the power generator, it is possible to achieve a good balance between thrust generation and power generation.

[0056] Equipping a multicopter with an internal combustion engine and using it to generate thrust and / or electricity contributes to increased payload and flight time. It is desirable to control the attitude of a multicopter by rotating the propellers with a motor, which has better response characteristics than an internal combustion engine. Therefore, in applications requiring precise control of the multicopter's attitude, it is desirable to employ a parallel hybrid drive or series hybrid drive to increase the payload and flight time. If the rotary drive device 3 is equipped with a mechanism for changing the pitch angle of each blade of the multiple rotors 2, the attitude can also be adjusted by changing the pitch angle of each blade.

[0057] Increased payload and flight time may further expand the applications of multicopters. For example, in the agricultural field, multicopters are currently being used for spraying pesticides or monitoring crop growth conditions. However, by connecting various ground implements (hereinafter, sometimes simply referred to as "implements") to a multicopter, various agricultural tasks can be performed from the air. Agricultural implements are sometimes called "implements." Examples of implements include sprayers that spray pesticides on crops, mowers, seeders, spreaders, rakes, balers, harvesters, plows, harrows, or rotary tillers. Work vehicles such as tractors are not included in the "implements" of this disclosure.

[0058] In the example shown in FIG. 1C , a work implement 200 is coupled to the multicopter 10. The work implement 200 can spray, for example, pesticides or fertilizers on a field or crops within the field. Increasing the payload and flight time allows for a larger and / or more versatile work implement 200. For example, by changing the work implement 200 coupled to the multicopter 10, a variety of ground tasks (agricultural operations) can be performed, including liquid and granular application of pesticides, fertilization, thinning, weeding, transplanting, direct seeding, and harvesting. The work implement 200 may be equipped with a mechanism such as a robotic hand. In this case, a single work implement 200 can perform a variety of ground tasks. If the work implement 200 has a sufficient space to accommodate materials, the work implement 200 can also be used to transport agricultural materials or harvested products over a wide area. The work implement 200 can be coupled to the multicopter 10 in a variety of ways. The multicopter 10 may suspend and tow the work machine 200 by a cable. The work machine 200 towed by the multicopter 10 can also perform ground work while being towed while the multicopter 10 is flying or hovering. The work machine 200 during work may be in the air or on the ground.

[0059] 1C , the multicopter 10 includes a power supply device 76. The power supply device 76 is a device that supplies power to the work machine 200 from a drive energy source, such as the battery 52 or the power generation device 8, included in the multicopter 10. Various functions of the work machine 200 can be performed using this power. The work machine 200 includes actuators such as motors that operate using power obtained from the power supply device 76 of the multicopter 10. The work machine 200 preferably includes a battery that stores power.

[0060] FIG. 2A is a block diagram illustrating an example of the basic configuration of a battery-powered multicopter 10. The battery-powered multicopter 10 includes multiple rotors 12, multiple motors 14 for rotating the rotors 12, multiple ESCs (electric speed controllers) 16 each having a motor drive circuit for driving the motors 14, a battery 52 for supplying power to the corresponding motors 14 via each ESC 16, a control device 4a for controlling the multiple ESCs 16 to control attitude and perform flight, a sensor group 4b, a communication device 4c, and a power supply device 76 electrically connected to the battery 52. ​​For simplicity, FIG. 2A illustrates the rotors 12, motors 14, and ESCs 16 as a single block, but the number of rotors 12, motors 14, and ESCs 16 is actually multiple. This also applies to FIGS. 2B and 2C. The ESC 16 may be included in the control device 4a.

[0061] The control device 4a can receive control commands wirelessly, for example, from a ground station 6 located on the ground via the communication device 4c. The number of ground stations 6 is not limited to one and may be distributed across multiple locations. The communication device 4c can also receive control commands wirelessly from a control device operated by a pilot on the ground. The control device 4a may have the function of automatically or autonomously performing takeoff, flight, obstacle avoidance, and landing operations based on sensor data obtained from the sensor group 4b. The control device 4a may be configured to communicate with the work machine 200 connected to the power supply device 76 and acquire a signal indicating the status of the work machine 200 from the work machine 200. The control device 4a may also provide the work machine 200 with a signal that controls the operation of the work machine 200. Furthermore, the work machine 200 may generate a signal instructing the operation of the multicopter 10 and transmit it to the control device 4a. Such communication between the control device 4a and the work machine 200 can be performed via wired or wireless communication.

[0062] FIG. 2B is a block diagram showing an example of the basic configuration of a series hybrid drive multicopter 10. Similar to the battery-powered multicopter 10, the series hybrid drive multicopter 10 includes multiple rotors 12, multiple motors 14, multiple ESCs 16, a control device 4a, a sensor group 4b, and a communication device 4c. The illustrated series hybrid drive multicopter 10 further includes an internal combustion engine 7a, a fuel tank 7b for storing fuel for the internal combustion engine 7a, a power generation device 8 driven by the internal combustion engine 7a to generate electric power, a power buffer 9 for temporarily storing the electric power generated by the power generation device 8, and a power supply device 76 electrically connected to the power buffer 9. The power buffer 9 is, for example, a battery such as a secondary battery. The electric power generated by the power generation device 8 is supplied to the motor 14 via the power buffer 9 and the ESC 16. The electric power generated by the power generation device 8 may also be supplied to the work machine 200 via the power supply device 76.

[0063] FIG. 2C is a block diagram showing an example of the basic configuration of a parallel hybrid drive multicopter 10. Similar to the series hybrid drive multicopter 10, the parallel hybrid drive multicopter 10 includes multiple rotors 12, multiple motors 14 that respectively drive the multiple rotors 12, multiple ESCs 16, a control device 4a, a sensor group 4b, a communication device 4c, an internal combustion engine 7a, a fuel tank 7b, a power generator 8, a power buffer 9, and a power supply device 76. The parallel hybrid drive multicopter 10 further includes a drive train 27 that transmits the driving force of the internal combustion engine 7a, and a rotor 22 that rotates by receiving the driving force of the internal combustion engine 7a from the drive train 27. One of the rotor 12 and the rotor 22 may be referred to as the “first rotor” and the other as the “second rotor” to distinguish them from each other. The number of rotors 22 connected to the drive train 27 and rotating may be one or more.

[0064] In the parallel hybrid drive multicopter 10, the internal combustion engine 7a not only drives the power generation device 8 to generate electricity, but also mechanically transmits energy to the rotor 22 to rotate the rotor 22. On the other hand, in the series hybrid drive multicopter 10, all of the rotors 12 are rotated by the electric power generated by the power generation device 8. For this reason, in the series hybrid drive multicopter 10, if the power generation device 8 is, for example, a fuel cell, the internal combustion engine 7a is not an essential component.

[0065] Below, an example of the configuration and operation of an unmanned aerial vehicle according to an embodiment of the present disclosure will be described, taking a multicopter that uses parallel hybrid drive as an example.

[0066] <Basic Configuration> Fig. 3A is a schematic top view of the multicopter 100 according to this embodiment, and Fig. 3B is a side view thereof. Fig. 3B illustrates a work implement 200 coupled to the multicopter 100. In addition to or instead of the work implement 200, luggage, agricultural materials, other machinery, or containers, cases, or packages capable of accommodating these items may be coupled to the multicopter 100. Hereinafter, the weight of the work implement 200 and the work implement itself may be referred to as the "payload." The "coupling" between the multicopter 100 and the work implement 200 or the like may be performed using various tools or devices.

[0067] The multicopter 100 shown in FIG. 3A includes eight sub-rotors 12 and two main rotors 22. Each sub-rotor 12 is composed of four sets of propellers 12a and 12b that rotate coaxially and in opposite directions. Each of the propellers 12a and 12b has two blades. The propellers 12a and 12b are rotated by a motor 14. The four sets of propellers 12a and 12b that rotate coaxially and in opposite directions are located at the vertices of a square. The main rotor 22 is composed of two propellers 22a that rotate in opposite directions at different positions. Each propeller 22a has four blades. The eight propellers 12a and 12b of the sub-rotor 12 have the same pitch angle and diameter. The two propellers 22a of the main rotor 22 also have the same pitch angle and diameter. The diameter of the propeller 22a is 1.2 times or more, for example, 1.4 times or more and 2.0 times or less, the diameter of the propellers 12a and 12b.

[0068] The multicopter 100 includes an airframe 110 having four arms 110A for the sub-rotors 12 and two arms 110B for the main rotors 22. The airframe 110 supports an airframe body 120 including various electronic and mechanical components, which will be described later.

[0069] In the example of FIG. 3B , the airframe main body 120 has a power supply device 76 and an actuator 78 used for coupling to the work machine 200, etc. The power supply device 76 is a device that supplies power generated within the airframe main body 120 to the work machine 200. The actuator 78 is a device such as an electric motor that performs an operation to couple the work machine 200 to the airframe main body 120 of the multicopter 100. In the example of FIG. 3B , the actuator 78 drives a mechanism that winds up a cable connecting the airframe main body 120 and the work machine 200. This cable may include a power supply line for supplying power (external power) for the work machine 200 from the multicopter 100, and a communication line for communication between the multicopter 100 and the work machine 200.

[0070] <System Configuration> FIG. 4 is a block diagram showing an example of a system configuration of the multicopter 100 according to this embodiment.

[0071] In the illustrated example, the airframe 120 of the multicopter 100 has a control device 30 including a flight controller 32, a sensor group 72, and a communication device 74. These are basically the same as the control device 4a, sensor group 4b, and communication device 4c that the airframe 4 of the multicopter 10 has, as described with reference to FIG. 1A.

[0072] The multicopter 100 of this embodiment includes eight sub-rotors 12, eight motors 14 for rotating the eight sub-rotors 12, and eight ESCs for controlling the eight motors 14. Each ESC 16 receives a signal (motor control signal) for controlling the motor 14 from the control device 30 via a wiring 82. The motor control signal is, for example, a PWM (Pulse With Modulation) signal. When the motor control signal is a PWM signal, the duty cycle of the PWM signal can indicate an analog value of the motor rotation speed. Each ESC 16 controls the rotation speed of the motor 14 connected to that ESC 16 based on the motor control signal from the control device 30. While FIG. 4 illustrates one set of "sub-rotors 12, motors 14, and ESCs 16" for simplicity, the multicopter 100 of this embodiment includes eight sets of "sub-rotors 12, motors 14, and ESCs 16." The number of these sets is not limited to eight.

[0073] The control device 30 is connected to each of the ESCs 16 via electrically independent wiring 82, and can individually control each of the eight ESCs 16. As described above, the sub-rotors 12 are used not only to generate lift but also for attitude control. Attitude control is achieved by the flight controller 32 of the control device 30 obtaining measured or estimated values ​​indicating the attitude of the airframe 120 from the sensors 72, determining the current attitude of the airframe 120, and controlling the rotational speed of each of the motors 14 in accordance with the difference from the target attitude.

[0074] The aircraft body 120 includes a main rotor drive unit 24 that drives the main rotor 22 and a main rotor control unit 26 that controls the main rotor drive unit 24. In this embodiment, the main rotor drive unit 24 is an internal combustion engine. Therefore, the main rotor control unit 26 includes an engine control unit (ECU). The main rotor control unit 26 acquires sensor data, such as the accelerator position, intake air temperature, engine speed, and temperatures of various components, of the main rotor drive unit 24, which is an internal combustion engine, and controls the internal combustion engine. The main rotor control unit 26 is connected to the control device 30 via wiring 82, such as a CAN (Controller Area Network) bus. The main rotor control unit 26 is configured to output an engine control signal based on a signal transmitted from the control device 30. The engine control signal includes, for example, a throttle position. A digital-to-analog converter (DAC) and / or a voltage converter may be connected between the control device 30 and the main rotor control unit 26. A mechanical device such as a clutch and a reducer may be provided between the main rotor drive section 24 and the main rotor 22.

[0075] The main rotor drive unit 24 is preferably an internal combustion engine with little vibration. In this embodiment, the main rotor drive unit 24 is, for example, an opposed-piston engine. Opposed-piston engines are disclosed, for example, in Japanese Patent No. 5508604. The entire contents of Japanese Patent No. 5508604 are incorporated herein by reference.

[0076] The main rotor drive unit 24, which is an internal combustion engine, can generate electricity by driving a power generator 42, such as an alternator. In this embodiment, the power generator 42 has the structure of an AC synchronous motor having a rotor and a stator. Therefore, when the main rotor drive unit 24 is started, the power generator 42 can also function as a "starter" by rotating the rotor when current is applied. The power generator 42 rectifies the AC generated by power generation and converts it into DC. The power generator 42 generates DC power required to drive the motor 14 and supplies it to each ESC 16 via wiring 80. The power generator 42 is configured to output a DC voltage of, for example, 250 V or higher. Note that the wiring 80 is a power wiring, and the wiring 82 is a signal wiring. Each of the wirings 80 and 82 includes multiple conductors.

[0077] The power generation device 42 is connected to a power management device 44. The power management device 44 is connected to the control device 30 and a battery management device 54, which will be described later. The power management device 44 can control the amount of power generated by the power generation device 42 based on signals from the control device 30 or the battery management device 54. This amount of power generation can be variably controlled by the power management device 44 in accordance with the power required by the motor 14 and the battery 52, even when the engine speed of the main rotor drive unit 24, which is an internal combustion engine, is constant.

[0078] The aircraft body 120 further includes a battery 52 in the form of a plurality of cells, such as a lithium ion secondary battery, connected in series or in parallel, and a battery management device 54 that controls the charging and discharging of the battery 52 .

[0079] The battery 52 receives DC power from the power generation device 42 via a power switch 56 and can be charged by the power. The operation of the power switch 56 can be controlled by a battery management unit 54 and the control device 30. The battery management unit 54 is a device that measures or estimates parameter values ​​that define the state of the battery 52, such as the current flowing through the battery 52, cell voltage, cell balance, state of charge (SOC), state of health (SOH), and temperature.

[0080] The battery management unit 54 can control the power switch 56 depending on the state of the battery 52. ​​For example, when the battery 52 is in a state requiring charging, the battery management unit 54 electrically connects the power generation device 42 and the battery 52 using the power switch 56, and supplies power from the power generation device 42 to the battery 52 to perform a charging operation. At this time, the battery management unit 54 controls the power management unit 44 to increase the amount of power generated by the power generation device 42 so that the power supplied to the ESC 16 does not drop below a desired level. On the other hand, when the battery 52 is in a state requiring no charging, the battery management unit 54 disconnects the electrical connection between the power generation device 42 and the battery 52 using the power switch 56, and stops charging the battery 52.

[0081] In this embodiment, the battery 52 has a storage capacity that allows the aircraft to continue to fly to a location where landing is possible and land there, by continuing to generate lift and control attitude using the sub-rotor 12, even if power generation by the power generation device 42 stops for some reason and lift from the main rotor 22 is lost. In other words, when the multicopter 100 of this embodiment is flying normally, the power required to drive the sub-rotor 12 can be supplied to the ESC 16 from the power generation device 42, rather than from the battery 52. ​​Therefore, even if the payload and flight time are increased, there is little need to increase the storage capacity of the battery 52 accordingly.

[0082] The power stored in the battery 52 can be output as a DC voltage of, for example, 250 V or higher. However, this DC voltage decreases as the charging rate decreases. Therefore, when the charging rate falls below a predetermined level, the battery management device 54 operates to supply part of the DC power from the power generation device 42 to the battery 52 to charge the battery 52.

[0083] The battery 52 is connected to a power circuit board 60. The power circuit board 60 has a function of stepping down the voltage output from the battery 52 to, for example, 24 V, 12 V, or 5 V. The DC voltage output from the battery 52 is converted to a desired voltage by the power circuit board 60 and then supplied to other electronic components. In the example of FIG. 4 , the power stepped down by the power circuit board 60 is supplied to the control device 30 and the actuator 78 via wiring 80.

[0084] In the example shown in FIG. 4, the power management unit 44 and the battery management unit 54 are separate components, but a single control unit (computer or ECU) may function as both the power management unit 44 and the battery management unit 54.

[0085] 4 , the power supply device 76 is electrically connected to the power generation device 42 or the battery 52 by a power switch 56. The power supply device 76 in this example is configured to supply power (external power) generated within the machine body 120 to an external machine or device such as a work machine 200.

[0086] The airframe main body 120 may have a configuration not shown in FIG. 4 . For example, the airframe main body 120 may include a fuel tank that stores fuel necessary for the operation of the main rotor drive unit 24, a water-cooling or air-cooling device for cooling the main rotor drive unit 24, and electrical components such as lighting devices and an electric pump. The electrical components can be operated by power that has been stepped down to a predetermined voltage by the power circuit board 60. A battery for the electrical components (auxiliary battery) may be provided and configured to supply power to the electrical components. Such an auxiliary battery may be charged by the battery 52 or the power generation device 42.

[0087] In this embodiment, the motor 14 functions as a plurality of "attitude control devices" that respectively drive a plurality of first rotors (sub-rotors) 12. In addition, the main rotor drive unit 24, which is an internal combustion engine, functions as a "main thrust generating device" that drives the second rotor (main rotor) 22.

[0088] In this embodiment, the control device 30 can change the ratio (power ratio) between the first drive power output from the multiple motors 14 and the second drive power output from the main rotor drive unit 24. This point will be described in detail below.

[0089] Generally, the responsiveness of the motor 14 is superior to that of an internal combustion engine. If the time from when a torque command signal is input until the torque required to rotate the rotors 12, 22 reaches a target torque value is called the "response time," the response time of the motor is, for example, approximately 1 / 100 of the response time of the internal combustion engine. Therefore, to control the attitude of the multicopter 100, it is desirable to detect the difference between the current and target attitude angles of the multicopter 100 and control the rotational speed of each of the multiple sub-rotors 12 with a high response speed so as to reduce this difference. An increase in rotor rotational speed results in an increase in thrust. By adjusting the thrust of each of the multiple sub-rotors 12, the attitude of the multicopter 100 can be controlled quickly and with high precision.

[0090] On the other hand, an internal combustion engine can efficiently generate large thrust. The sub-rotor 12 is rotated using electric power generated by the power of the main rotor drive unit 24, which is an internal combustion engine. However, energy loss occurs when converting mechanical energy into electrical energy. Therefore, from the viewpoint of improving energy consumption efficiency, it is preferable that the main rotor drive unit 24 be used to rotate the main rotor 22 and generate the main thrust. Furthermore, to increase the thrust of the main rotor 22, it is preferable that the diameter of the main rotor 22 be larger than the diameter of each of the multiple first rotors 12.

[0091] However, when the main rotor 22, which generates the main thrust, generates a large thrust, the large thrust and rotational moment may actually inhibit the attitude control function of the sub-rotor 12. As a result, even if multiple sub-rotors 12 are rotated using multiple motors 14 with excellent response, a delay in response may occur in attitude control. On the other hand, if the rotation speed of the main rotor 22 is reduced, attitude control performance improves, but energy consumption efficiency decreases.

[0092] Battery-powered multicopters use various algorithms to adjust the torque of each of the multiple motors to regulate the thrust of each rotor and control it to a desired attitude. When using multiple motors for attitude control, adding a rotor rotated by an internal combustion engine can complicate the calculations required for attitude control. Fixing the "ratio" between the drive power output from the multiple motors and the drive power output from the internal combustion engine is an effective way to avoid this complexity. For this reason, conventional parallel hybrids have adopted a control method that fixes this ratio.

[0093] However, as a result of studies by the inventors, it has been found that when using the multicopter 100 for agricultural work, for example, it is preferable to make the above-mentioned "ratio" variable rather than fixed, compared to when flying the multicopter 100 for simple logistics or surveillance purposes. This is because when flying the multicopter 100 for agricultural purposes, it flies under a variety of different conditions, such as various agricultural tasks (ground tasks) within a field, traveling between multiple fields, and transporting agricultural materials or harvested crops. The level of response speed required for attitude control varies greatly depending on these conditions. Furthermore, when various types of implements with different weights and shapes are appropriately selected and connected depending on the type of agricultural work, the required lift and attitude control precision can also vary greatly.

[0094] <Power Control> In the present embodiment, each of the multiple motors 14 can operate by receiving at least one of power (first power) from the battery 52 and power (second power) from the power generation device 42. The battery 52 and the power generation device 42 function as "power sources." A wiring 80 that supplies power from the power source (power generation device 42 and battery 52) is connected to each of the multiple motors 14. Power can also be supplied from the power source to devices other than the motors 14. A wiring (second wiring) 80A branching from the wiring (first wiring) 80 electrically connects the power source and the power supply device 76, allowing power to be supplied from the power source to the work machine 200.

[0095] In this embodiment, the battery management device 54 functions as a first power control device that controls charging and discharging of the battery 52, and the power management device 44 functions as a second power control device that controls power generation by the power generation device 42. The battery management device 54, which is the first power control device, is configured to control the power management device 44, which is the second power control device.

[0096] By including the battery management device 54 and the power management device 44, the multicopter 100 in this embodiment is capable of performing at least one of the following control operations: (1) The battery management device 54, which is a first power control device, controls the power management device 44, which is a second power control device, in accordance with the state of the battery 52. ​​(2) The battery management device 54, which is a first power control device, controls the power management device 44, which is a second power control device, in accordance with the work content of the multicopter 100 to adjust the amount of power generation. (3) The battery management device 54, which is a first power control device, controls the charge rate of the battery 52 in accordance with flight conditions including the flight altitude of the multicopter 100. (4) The battery management device 54, which is a first power control device, controls the charge rate of the battery 52 in accordance with the distance from the multicopter 100 to a possible landing point.

[0097] An example of the above control operation by the battery management device 54 will now be described.

[0098] First, a configuration example of the battery management device 54 will be described with reference to Fig. 5. Fig. 5 is a block diagram showing a configuration example of the battery management device 54. In the illustrated example, the battery management device 54 has a cell monitoring circuit 54a that monitors the state (voltage, temperature, etc.) of each of the multiple single cells (cells) included in the battery 52, and a microcontroller (Micro Controller Unit: MCU) 54b that estimates the state of the battery 52 and performs management operations for the battery 52.

[0099] The cell monitoring circuitry 54a may be configured to measure the voltage of each cell and perform cell balancing during charging. The cell monitoring circuitry 54a may also include protection circuitry to prevent overcharging and over-discharging of each cell. Such protection circuitry may be provided in battery packs each containing multiple cells.

[0100] The MCU 54b can acquire current measurements from a current sensor 53a that measures the current flowing through the battery 52. ​​The MCU 54b can also acquire various sensor data, such as temperature measurements of the battery 52, from other sensors. The battery management unit 54 can be programmed to perform various calculations, for example, to estimate the state of charge (SOC) of the battery 52. ​​The SOC is one of the state variables that define the state (state of charge) of the battery 52. ​​Parameters that define the state of the battery 52 are not limited to the state of charge, but can also include variables such as the charge amount (remaining charge), cell voltage, battery temperature, state of health (SOH), and full charge capacity (FCC).

[0101] As shown in FIG. 4, the battery management device 54, which functions as a first power control device, can control the electrical connection state between the battery 52 and wiring 80 that connects the power generation device 42 to the motor 14.

[0102] <(1) Control of the Power Management Device According to the State of the Battery> The battery management device 54 can control the power management device 44, which is the second power control device, according to the state of the battery 52.

[0103] For example, when the state of charge (SOC) of the battery 52 is equal to or higher than a first reference value (e.g., 60%), the battery management device 54 controls the power management device 44 to supply electric power from the power generation device 42 to the motor 14 without charging the battery 52 from the power generation device 42. On the other hand, for example, when the state of charge (SOC) of the battery 52 falls below the first reference value, the battery management device 54 controls the power management device 44 to charge the battery 52 from the power generation device 42. This charging may be continued until the state of charge (SOC) of the battery 52 reaches a second reference value (e.g., 90%).

[0104] The above operation is an example. For example, the first reference value may be 80% and the second reference value may be 90%. The first reference value and the second reference value do not need to be fixed values.

[0105] <(2) Control of the power management device according to the work content> The battery management device 54 can control the power management device 44 to adjust the amount of power generation according to the work content of the multicopter 100. The work content of the multicopter 100 is specified by a work plan. Then, a work implement 200 selected according to the work content can be connected to the multicopter 100. The work plan will be described in detail below.

[0106] The work plan includes information about one or more agricultural tasks to be performed by the multicopter 100. When tasks are performed by multiple multicopters 100, different work plans may be created for each multicopter 100. The work plan includes information about one or more agricultural tasks to be performed by each multicopter 100 and the fields on which each task is to be performed. The work plan may include information about multiple agricultural tasks to be performed by each multicopter 100 over multiple work days and the fields on which each task is to be performed. More specifically, the work plan may be a database containing work schedule information indicating which multicopters will perform which tasks in which fields at which times for each work day. Therefore, for example, when a work plan is provided to the control device 30 of the multicopter 100, the control device 30 can obtain information about how the power consumption of the multicopters 100 and the work implement 200 changes as the tasks start and progress. In this embodiment, the battery management unit 54 can control the power management unit 44 in accordance with the content of the work defined by such a work plan, in other words, in accordance with changes in power consumption. That is, when the remaining power in the battery 52 is not at a sufficient level to supply the necessary power consumption and perform the work, the battery management unit 54 is configured to control the power management unit 44 to increase the charging rate of the battery 52 and increase the amount of power generation.

[0107] An example of a work plan that defines the work content of the multicopter 100 (and the work implement 200) will be described in detail below. In this embodiment, the work plan can be created by a management system (agricultural management system) for the multicopter 100.

[0108] FIG. 6 is a diagram illustrating an example of an agricultural management system that can be used in this embodiment. The agricultural management system illustrated in FIG. 6 includes multiple multicopters 100 and a management device 600. FIG. 6 also illustrates multiple terminal devices 400 used by multiple users. The management device 600 is a computer managed by a business operator that operates the agricultural management system. The multicopters 100, the terminal devices 400, and the management device 600 can communicate with each other via a communication network N. While FIG. 6 illustrates three multicopters 100, the agricultural management system may include two or fewer multicopters 100 or four or more multicopters 100. The agricultural management system may include not only multicopters 100 but also multiple different types of agricultural machinery, such as tractors, rice transplanters, and combine harvesters. Each multicopter 100 can perform its assigned agricultural work in a designated field according to instructions from the management device 600. In addition, the operation of the multicopter 100 may be performed by a user (operator) from the ground, in which case the management device 600 can be used by the user or other people to create work plans.

[0109] The agricultural management system shown in FIG. 6 can be suitably used for managing agricultural work using multiple multicopters 100 that fly automatically or manually. The management device 600 may create a work plan for each multicopter 100 based on information indicating a general plan for agricultural work input by each user using their respective terminal device 400, and may plan paths for each multicopter 100 based on the work plan. The management device 600 may be a collection of multiple computers. For example, the management device 600 may include a computer that creates a work plan for each multicopter 100 and a computer that plans paths for each multicopter 100.

[0110] The management device 600 determines the route along which each multicopter 100 should travel so that each multicopter 100 performs a predetermined agricultural task (e.g., tilling, sowing, planting, pest control, fertilizing, harvesting, etc.). The management device 600 references a map of the area in which each multicopter 100 will travel, generates a route on the map along which each multicopter 100 should travel, and transmits the route information to the terminal device 400 of each multicopter 100 or the user. Multicopters 100 capable of autonomous flight travel based on the received route information and perform the predetermined agricultural task in the field assigned to each multicopter 100. In the case of a manually flown multicopter 100, the user can operate the multicopter 100 based on the route information received by the terminal device 400.

[0111] The multicopter 100 in this embodiment can be equipped with or towed by a work implement 200, and therefore the multicopter 100 can fly over a field while performing agricultural work according to the type of work implement 200. The multicopter 100 can also move between fields or fly between a storage facility and a field.

[0112] In a preferred embodiment, the multicopter 100 has an automatic flight function. That is, the multicopter 100 can fly not only manually but also through the operation of the control device 30. In a preferred embodiment, the multicopter 100 can fly not only over the field but also outside the field automatically or remotely.

[0113] The control device 30 of the multicopter 100 in this embodiment can also automatically fly the multicopter 100 based on the position of the multicopter 100 and information about the target route generated by the management device 600. In addition to controlling the flight of the multicopter 100, the control device 30 can also control the operation of the work implement 200. This allows the multicopter 100 to perform agricultural work using the work implement 200 while automatically flying within a field. During flight, the multicopter 100 flies while generating a local route along the target route that can avoid obstacles based on sensor data output from a group of sensors 72, such as an imaging device or a LiDAR sensor.

[0114] The management device 600 may be, for example, a server computer that centrally manages information about farm fields and agricultural work on the cloud and supports agriculture by utilizing data on the cloud. The management device 600 may, for example, create a work plan for each multicopters 100 and perform global path planning for each multicopters 100 in accordance with the work plan.

[0115] The management device 600 generates a target route in the field based on information about the field. For example, the management device 600 can generate a target route in the field based on various information such as the pre-registered outline of the field, the area of ​​the field, the location of the entrance and exit to the field, the size of the multicopter 100, the model or size of the work implement 200, the type of work, the type of crop being cultivated, the crop growing area, the crop growth status, or the spacing between crop rows or furrows. The management device 600 can generate a target route in the field based on, for example, information input by a user using the terminal device 400 or another device. The management device 600 generates a route in the field so as to cover, for example, the entire work area where work is to be performed.

[0116] The terminal device 400 is a computer used by a user located remotely from the multicopter 100. The terminal device 400 may be a mobile terminal such as a laptop computer, smartphone, or tablet computer as shown in FIG. 6, or a stationary computer such as a desktop personal computer (PC). The terminal device 400 displays a setting screen on its display, allowing the user to input information necessary to create a work plan (e.g., a schedule for each agricultural task). When the user inputs the necessary information on the setting screen and performs a send operation, the terminal device 400 transmits the input information to the management device 600. The management device 600 creates a work plan based on that information. The terminal device 400 may also be used to register one or more fields where the multicopter 100 will perform agricultural tasks.

[0117] FIG. 7 is a diagram illustrating an example of a work plan for each multicopter 100. In this example, the work plan includes, for each registered multicopter 100, information indicating the date and time of the agricultural work, the field, the work content, and the agricultural implement 200 to be used. The work plan is not limited to the format shown in FIG. 7 and may include other information related to the work. For example, the work plan may include information such as the type and amount of pesticide or fertilizer to be applied. Based on this work plan, the processor included in the management device 600 generates a route for each multicopter 100 for each work day and issues instructions for the agricultural work to each multicopter 100. The work plan may be downloaded by the control device 30 of the multicopter 100 and stored in the storage device 37 (described later). In this case, the control device 30 may autonomously start operation according to the schedule indicated by the work plan stored in the storage device 37.

[0118] The management device 600 may create a work plan based not only on information indicating the approximate timing of agricultural work, but also on information input by each user using the terminal device 400. For example, the management device 600 may create a work plan based on information indicating a rough plan for each type of agricultural work in one or more fields managed by each user.

[0119] Fig. 8 is a diagram showing an example of a setting screen 760 displayed on the display screen of the terminal device 400. In response to a user's operation using the input device, the processor of the terminal device 400 starts up application software for creating a work plan and displays the setting screen 760 shown in Fig. 8 on the display screen. The user can input outline plan information required for creating a work plan on this setting screen 760.

[0120] 8 shows an example of a setting screen 760 for when tilling with fertilizer application is performed as agricultural work in a rice field. The setting screen 760 is not limited to the one shown in the figure and can be modified as appropriate. The setting screen 760 in the example of FIG. 8 includes a period setting section 761, a time setting section 762, a planting variety selection section 763, a field selection section 764, an operation selection section 765, a machine selection section 766, a fertilizer selection section 767, and an application amount setting section 768.

[0121] The period input by the user is displayed in the period setting section 761. The user inputs the period during which the user wishes to perform the farm work. The days included in the input period are set as candidate days for performing the farm work.

[0122] The time setting section 762 displays the work time input by the user. The user inputs the work time for which the user wishes to perform the farm work. The work time is specified by a start time and an end time. The input work time is set as a candidate time for performing the farm work.

[0123] The crop variety selection section 763 displays a list of varieties of crops to be cultivated (i.e., planted). The user can select a desired variety from the list. In the example of Figure 8, the rice variety "Koshiibuki" is selected.

[0124] The field selection section 764 displays the fields on the map. The user can select any field from the displayed fields. In the example of FIG. 8, the portion showing "Field A" is selected. In this case, the selected "Field A" is set as the field where agricultural work will be performed. The user can also select multiple fields at the same time.

[0125] The work selection section 765 displays a plurality of farming works required to cultivate the selected crop. The user can select one farming work from the plurality of farming works. In the example of FIG. 8, "plowing" is selected from the plurality of farming works. In this case, the selected "plowing" is set as the farming work to be performed.

[0126] The machine selection unit 766 is a section for setting the multicopter to be used in the agricultural work. The machine selection unit 766 may display, for example, the type or model of the multicopter registered in advance by the management device 600, and the type or model of the work implement 200 that can be used. The user can select a specific machine from the displayed machines. In the example of FIG. 8 , the work implement 200 with the model number "XX4511" is selected. In this case, the work implement 200 is set as the machine to be used in the agricultural work.

[0127] The names of multiple fertilizers that have been registered in advance are displayed in the fertilizer selection section 767. The user can select a specific fertilizer from the multiple fertilizers that are displayed. The selected fertilizer is set as the fertilizer to be used in the farm work.

[0128] The spray amount setting section 770 displays a numerical value input from the input device 420. The input numerical value is set as the spray amount.

[0129] When the desired period, work hours, crop variety, field, work, fertilizer, and application amount are entered on the setting screen 760 and "Register" is selected, the communication device of the terminal device 400 transmits the entered information to the management device 600. The processor of the management device 600 stores the received information in a storage device.

[0130] The agricultural work information managed by the management device 600 is not limited to the above. For example, the type and application amount of pesticides used in the field may be set on the setting screen 760. Information about agricultural work other than the agricultural work shown in FIG. 8 may also be set.

[0131] The management device 600 creates a work plan for each multicopter 100 to perform agricultural work based on information received from each user's terminal device 400. For example, the management device 600 determines the actual work date and work time for each multicopter 100 to perform the agricultural work. For example, the management device 600 determines the date and time for performing the agricultural work in each field by comprehensively considering the number, distribution, and usage status of the multicopters 100, the distribution of fields in the area where agricultural work is performed, the desired work date and time of each user, and the estimated work period in the area. The determination of the date and time for performing the agricultural work in each field may be performed using an algorithm utilizing artificial intelligence (AI), such as a deep neural network. The management device 600 notifies the terminal device 400 used by the user of the determined date and time for performing the agricultural work. If the determined date and time for performing the agricultural work differs from the desired date and time of the user, information to that effect may be notified. The management device 600 executes a route plan for each multicopter 100 for each work day based on the determined dates and times when agricultural work will be performed in each field.

[0132] When a work plan is created by the management system described above, the battery management unit 54 in this embodiment can control the power management unit 44 to efficiently increase or decrease the amount of power generation. That is, as will be described later, the amount of power generation can be increased in synchronization with the operation of the work machine 200.

[0133] Furthermore, when a work plan is prepared, the battery management device 54 in this embodiment can monitor the state of the battery 52 (particularly the charging rate) and control the power management device 44 to efficiently increase or decrease the amount of power generation. That is, as will be described later, the amount of power generation can be increased immediately before the work machine 200 starts to operate. Because the battery 52, such as a lithium-ion battery, is prone to deterioration if kept in a fully charged state, processing to increase the charging rate in time for the start of work by the work machine 200 is also effective in extending the life of the battery 52. ​​Such control of the charging rate will be described below.

[0134] (3) Control of Charging Rate According to Flight Conditions of the Multicopter, etc. For example, when the charging rate (SOC) of the battery 52 is equal to or higher than a first reference value (e.g., 60%), the battery management device 54 supplies electric power from the power generation device 42 to the motor 14 without charging the battery 52 from the power generation device 42. On the other hand, for example, when the charging rate (SOC) of the battery 52 falls below the first reference value, the battery management device 54 charges the battery 52 from the power generation device 42. This charging may be continued until the charging rate (SOC) of the battery 52 reaches a second reference value (e.g., 90%).

[0135] The above operation is an example. For example, the first reference value may be 80% and the second reference value may be 90%. The first reference value and the second reference value do not need to be fixed values.

[0136] The battery management device 54 can control the charge rate of the battery 52 according to flight conditions, including the flight altitude of the multicopter 100. The flight conditions are various parameters that determine the amount of power (power consumption) consumed per unit time by the multicopter 100 during flight, such as flight altitude, flight speed, wind direction and speed during flight, and payload size (weight). In this embodiment, the control device 30 calculates an estimated power consumption value based on the above parameters that define the flight conditions. In this embodiment, the battery management device 54 is configured to determine whether the multicopter 100 can descend and land to a possible landing point using only the power currently stored in the battery 52, based on the estimated power consumption value obtained from the control device 30. If it is determined that the multicopter 100 cannot descend and land to a possible landing point using only the power currently stored in the battery 52, the battery management device 54 initiates a charging operation to increase the charge rate of the battery 52. ​​This means increasing the first reference value described above. Such a change in the first reference value may be performed according to the type of work performed by the multicopter 100, because power consumption varies depending on the type of work. The details of the operations performed by the multicopter 100 will be described later.

[0137] The range with the first reference value as the lower limit and the second reference value as the upper limit is the "target range" of the state of charge control performed by the battery management device 54. As described above, this target range is preferably varied depending on the flight state or the working state. For example, if the battery 52 is used as an emergency backup power source in case the power generation device 42 fails, the power (first power) stored in the battery 52 only needs to be large enough to allow the aircraft to descend to the ground and land without using the power (second power) generated by the power generation device 42. In such a case, the power (first power) stored in the battery 52 can be reduced as the flight altitude decreases. Therefore, for example, the lower limit (first reference value) of the target range of the state of charge (SOC) can be varied depending on the flight altitude.

[0138] 9 is a side view schematically showing the lower limit (first reference value) of the target range of the state of charge (SOC) when the height (flight altitude) of the multicopter 100 from the ground GR is h4, h3, h2, or h1 (h4>h3>h2>h1>0). FIG. 10 is a graph schematically showing an example of the relationship between the height of the multicopter 100 from the ground GR and the lower limit (first reference value) of the target range of the state of charge (SOC).

[0139] 9 and 10 , in this example, the first reference value of the state of charge (SOC) can be reduced as the flight altitude of the multicopter 100 decreases. When the state of charge (SOC) of the battery 52 falls below the first reference value, the battery management device 54 controls the power management device 44 to increase the amount of power generation and charge the battery 52.

[0140] 10, the first reference value changes stepwise depending on the flight altitude, but may change linearly or in a curved manner. Also, in the example of FIG. 10, the first reference value of the state of charge (SOC) is 50% or more, but when the multicopter 100 flies or performs ground operations at a low altitude of, for example, 5 meters or less, the first reference value may be set to, for example, 50% or less.

[0141] The first reference value may be changed depending on whether the multicopter 100 is working in a field that is the target of ground work or flying and moving in an area other than the field.

[0142] (4) Control of Charging Rate According to Distance to Landing Point The battery management device 54 can control the charging rate of the battery 52 according to the distance from the multicopter 100 to a possible landing point.

[0143] As described above, the technical significance of controlling the charging rate according to the flight altitude is that the power consumption required for the multicopter 100 to descend and land at that flight altitude depends on the flight altitude. However, during flight, the multicopter 100 may fly to a position where it cannot land even if it descends directly downward. In such cases, it is preferable for the multicopter 100 to control the charging rate of the battery 52 based on the power consumption taking into account the distance to a possible landing point.

[0144] In a preferred embodiment, the control device 30 measures or estimates the position (self-position) of the multicopter 100 during flight based on sensor data obtained from the sensor group. The control device 30 may then calculate the distance from that position to a possible landing location based on map information or the like, and determine the first reference value based on that distance. This distance calculation is not limited to being performed by the control device 30, but may also be performed by a host computer, a computer at the ground station 6, or one or more computers connected to a communication network (described later). The battery management device 54 of the multicopter 100 can then perform charging processing through communication between these computers and the multicopter 100 to achieve the charge rate required for flying the distance to the landing location and landing.

[0145] In this way, the preferred target range of, for example, the state of charge (SOC) or charge amount of the battery 52 may vary not only depending on the flight altitude or location of the multicopter 100, but also on various conditions such as the type of work being performed. The type of work being performed by the multicopter 100 also depends on the type (model name, model number, power consumption, size, etc.) of the work machine 200 coupled to or towed by the multicopter 100. In this embodiment, target ranges of parameters that define the state of the battery 52 are selected according to various flight conditions or work being performed, and the battery management device 54 can control charging and discharging.

[0146] As described above, the battery management device 54 in this embodiment can control the amount of power generated by the power generation device 42 by controlling the power management device 44 when charging the battery 52 .

[0147] Next, an example of control of the power management device 44 by the battery management device 54 will be described with reference to FIG.

[0148] In step S10, the battery management unit 54 acquires a target range for a parameter (first parameter) such as the state of charge (SOC) that defines the state of the battery 52. ​​The target range can be specified by a first reference value that defines a lower limit and a second reference value that defines an upper limit. The target range can be provided to the battery management unit 54 from the control device 30. The control device 30 may estimate the required power based on a known flight plan or operation plan and determine the target range, or may acquire the target range from a higher-level computer or the ground station 6.

[0149] In step S12 , the battery management unit 54 obtains a measured or estimated value of a first parameter that defines the current state of the battery 52 .

[0150] In step S14, the battery management unit 54 acquires a measured or estimated value of a parameter (second parameter) that defines the current power generation state. The measured or estimated value of the second parameter can be provided to the battery management unit 54 from the power management unit 44 or the control unit 30. Examples of the second parameter include the power generated per unit time, the rotational speed of the main rotor drive unit (engine speed), and the output of the main rotor drive unit.

[0151] In step S16, the battery management unit 54 determines whether the measured or estimated value of the first parameter is lower than the target range. If the answer is No, the process returns to step S10. If the answer is Yes, in step S18, the battery management unit 54 adjusts the second parameter so that the measured or estimated value of the first parameter falls within the target range. For example, the battery management unit 54 provides the power management unit 44 with an instruction signal to increase the amount of power generation. The increase in the amount of power generation may be performed in predetermined increments. Alternatively, the battery management unit 54 may instruct the power management unit 44 on the amount of increase in the amount of power generation.

[0152] After the process in step S18, the process returns to step S10. In step S10, the target range of the first parameter is acquired, which may change dynamically depending on the flight state or the working state, as described above.

[0153] The above flow is an example, and the control of the power management unit 44 by the battery management unit 54 may be performed by another algorithm.

[0154] <External Power Supply> As described above, the multicopter 100 according to this embodiment includes a power supply device 76 that supplies external power from the battery 52 and the power generation device 42 to the work implement 200. An appropriate implement can be selected from a wide variety of interchangeable implements and attached to the agricultural work implement 200 depending on the ground work to be performed. Therefore, the drive power (energy consumption per unit time) of the work implement 200 strongly depends on the type of work implement 200 connected to the multicopter 100, in other words, the ground work to be performed by the work implement 200 connected to the multicopter 100. Therefore, in this embodiment, a "control device" controls the drive power from the power source (the battery 52 and the power generation device 42) depending on the current operating state or the planned operating state of the work implement 200 connected to the multicopter 100. This point will be described in more detail below.

[0155] In a preferred embodiment, the control device 30 provided in the multicopter 100 is configured to control at least one of the operation of the main rotor drive unit 24, which is an internal combustion engine shown in Figure 4, the operation of the motor 14, the charging and discharging of the battery 52, and the power generation by the power generation device 42, depending on the current operation or planned operation of the work machine 200.

[0156] For example, the control device 30 may start charging the battery 52 before the start of operation of the work machine 200, depending on the content of the planned operation of the work machine 200. Information indicating such planned operation can be obtained from the work plan described above. The control device 30 can also adjust the charging rate or charge amount of the battery 52 depending on the content of the operation of the work machine 200. The content of such operation of the work machine 200 is determined by the work content (work schedule) defined by the work plan described above, and the control device 30 can estimate the change over time in the power consumption of the work machine 200 based on the work schedule. Meanwhile, the content of the current operation of the work machine 200 during work is determined by the work plan described above or by commands received by the control device 30 from the user. Therefore, the control device 30 can increase or decrease the amount of power provided to the work machine 200 from the power supply device 76 in accordance with the increase or decrease in the power consumption of the work machine 200, based on the content of the current operation of the work machine 200 or the content of the planned operation.

[0157] The power required by the work machine 200 is the power consumed when the work machine 200 performs ground work, and is the power consumed by electrical components such as actuators provided in the work machine 200. In addition, if the work machine 200 is provided with a battery, the power required to charge the battery is also included.

[0158] In this way, the power supplied from the power supply device 76 of the multicopter 100 to the work machine 200 depends on the operation (operating state) of the work machine 200. Meanwhile, the power that the multicopter 100 can supply to the work machine 200 from the power supply device 76 is determined by the power consumption of the motor 14 provided in the multicopter 100, the charge / discharge amount of the battery 52, and the amount of power generated by the power generation device 42. The amount of power generated by the power generation device 42 can be adjusted by the operation of the main rotor drive unit 24. In this embodiment, the control device 30 is configured to control at least one of the operation of the main rotor drive unit 24, the operation of the motor 14, the charge / discharge of the battery 52, and the power generation by the power generation device 42, so that the amount of power required by the work machine 200 can be appropriately supplied from the power supply device 76 to the work machine 200.

[0159] An example of the "control device" here is not limited to the control device 30 in Fig. 4, but may include its host computer, a computer in a ground station, and / or a computer on the cloud. For simplicity, an example will be described below in which the control device 30 in Fig. 4 controls not only the state of the power source but also the operation of the main rotor drive unit 24 and the motor 14. Using the battery management device 54 and the power management device 44, the control device 30 can supply at least a portion of the power (first power) from the battery 52 and the power (second power) from the power generation device 42 as third power from the power supply device 46 to the work machine 200.

[0160] Depending on the content of the planned operation of the work machine 200, the control device 30 may start charging the battery 52 or increase the amount of power generated by the power generation device 42 before the start of this operation.

[0161] Next, an example of the operation of the external power supply will be described with reference to Figures 12 and 13. Figure 12 is a flowchart showing an example of the operation of the external power supply in this embodiment. Figure 13 is a graph showing an example of the relationship between the power consumed by the planned operation of the work machine 200 in this embodiment, the amount of power generated by the power generation device 42, and the engine speed. Here, the "engine speed" corresponds to the number of rotations per unit time (rotational speed) of the output shaft of the internal combustion engine that functions as the main rotor drive unit 24.

[0162] First, in step S20, the control device 30 acquires details of the current or planned operation of the work machine 200. The details of the operation of the work machine 200 may be acquired from the work machine 200 or from a work plan stored in a storage device provided in the control device 30. The details of the operation of the work machine 200 include the start time of the operation of the work machine 200. The details of the operation of the work machine 200 may also include at least one piece of information: the type of operation, the end time of the operation, the duration of the operation, the power required for the operation (power consumption per unit time), and the cumulative amount of power required until the end of the operation. "Power consumption of work machine" in FIG. 13 schematically illustrates the power consumption in an example in which the work machine 200 starts operating at time t1. In this example, the power consumption temporarily shows a relatively high value between time t1 and time t2, but maintains a relatively low value after time t2, and the operation of the work machine 200 stops at time t3. The change in power consumption over time shown in Figure 13 is merely an example, and may vary depending on the type of work machine 200 and the work performed by work machine 200. Furthermore, there are cases where the operation of work machine 200 is performed intermittently and repeatedly.

[0163] In step S22, the control device 30 determines the required amount of external power supply based on the details of the operation of the work machine 200. If the details of the operation of the work machine 200 acquired in step S20 include, for example, only the start time of the operation, the control device 30 can determine the required amount of external power supply based on, for example, a power consumption table for each work machine stored in the storage device. If the details of the operation of the work machine 200 acquired in step S20 include information on the power required for the operation, the control device 30 can determine that power as the required amount of external power supply.

[0164] In step S24, the control device 30 acquires information on the current power generation state (e.g., power generation amount) and battery state (e.g., charge amount) from the power management device 44 and the battery management device 54, and determines the possible amount of external power supply. Even if the current amount of power generation is small, the possible amount of external power supply can be high if the charge amount of the battery 52 is sufficiently high.

[0165] In step S26, the control device 30 determines whether the required amount of external power supply is greater than the available amount. If the answer is No, the process returns to step S20. If the answer is Yes, in step S28, the control device 30 increases the amount of power generated by the power generation device 42. In the example of FIG. 13 , the control device 30 increases the amount of power generated by the power generation device 42 at time g1, which is earlier than time t1. The control device 30 may change the increase in the amount of power generated by the power generation device 42 in response to changes in the required amount of external power supply. In the example of FIG. 13 , the increase in the amount of power generation is reduced at time g2 after time t2, and the amount of power generation is returned to the level before the increase at time g3 after time t3.

[0166] When increasing the amount of power generation, the control device 30 can first increase the engine speed of the main rotor drive unit 24, which is an internal combustion engine. The response speed of the increase in engine speed may not always be high. In such cases, it is preferable to start increasing the engine speed at time e1, which is earlier than time t1 when the work machine 200 starts operating, by the length of the response time. As a result, it is possible to reach the engine speed required to generate the required amount of power generation at time e2, which is earlier than time t1. In the example of FIG. 13 , the engine speed gradually increases from time e1 to time e2, then maintains a constant level and decreases to the pre-increase level from time e3. In this example, the engine speed does not change in response to relatively short-term fluctuations in the power consumption of the work machine 200. It is preferable to reduce the number of engine speed changes.

[0167] Next, the process proceeds to step S30, where the control device 30 charges the battery 52 with the electric power 28 generated by the power generation device 42. The amount of charge can be determined based on the required amount of external power supply.

[0168] In the above example, the required amount of external power supply (supply power) is determined based on the operation of the work machine 200, but such processing may not be performed and an algorithm such as the one below may be adopted.

[0169] Before the work machine 200 starts operating, charging of the battery 52 from the power generation device 42 is started, and the charging rate of the battery 52 is increased to a desired level (for example, 90% or more). In this case, it is preferable that the timing for starting charging of the battery 52 is set so that the charging rate reaches the desired level by the scheduled time when the work machine 200 starts operating.

[0170] - If the scheduled start time of operation of the work machine 200 is, for example, immediately after the multicopter 100 starts flying, and the charge rate of the battery 52 immediately after the multicopter 100 starts up is lower than the desired level, the control device 30 may start charging the battery 52 immediately after startup (for example, before flight starts) and increase the charge rate.

[0171] Before the work machine 200 starts operating, the amount of power generated by the power generation device 42 is increased by a preset amount, and the increased power is supplied to the work machine 200. The increase in the amount of power generation is preferably set to a level equal to or greater than the power required for operation of the work machine 200. In this case, the operation of the work machine 200 does not require the consumption of power from the battery 52. ​​If the power generation by the power generation device 42 is performed using the driving force of an internal combustion engine, which has a longer response time than an electric motor, the control device 30 can be configured to start increasing the driving force of the main rotor drive unit 24, for example, one second, preferably two or three seconds, before operation of the work machine 200 starts. A portion of the increased amount of power generation may be used to charge the battery 52 when it is not required for operation of the work machine 200.

[0172] In flight conditions in which the thrust of the main rotor 22 can be reduced (for example, when descending), the power transmitted from the main rotor drive unit 24 to the main rotor 22 may be reduced, and the proportion of the power output from the main rotor drive unit 24 used to drive the power generation device 42 may be increased. By using a mechanical device (for example, a clutch) provided between the main rotor 22 and the main rotor drive unit 24, the driving force generated by the main rotor drive unit 24 can be used efficiently to increase the amount of power generated by the power generation device 42.

[0173] FIG. 14 is a block diagram that schematically shows the connection state between the power supply device 76 and the work machine 200 in this embodiment.

[0174] 14 includes a power receiving terminal 210 electrically connected to the power supply device 76, an actuator 212 for performing ground work (agricultural work), an MCU 214 for controlling the actuator 212, and a communication terminal 216 for communicating with the multicopter 100. In contrast, the power supply device 76 includes a power transmitting terminal 76A electrically connected to the power receiving terminal 210 of the work device 200 to supply power, and a communication terminal 76B for communicating with the work device 200.

[0175] An example of the actuator 212 is one or more electric motors. The actuator 212 may be configured to rotate a pump for spraying pesticides or fertilizer, or to drive a robotic hand. The work machine 200 may include electrical components, a secondary battery, sensors, and mechanical components that are not shown in FIG. 14 . The secondary battery of the work machine 200 stores some or all of the power received from the power receiving terminal 210 and can supply that power not only to the actuator 212 but also to the MCU 214 and other electrical components.

[0176] Examples of the electrical connection between the power receiving terminal 210 and the power transmitting terminal 76A include direct contact that enables current to flow, connection via a conductive cable or wiring, and connection via wireless power transmission. Examples of the electrical connection between the communication terminals 216 and 76B also include direct contact that enables current to flow, connection via a communication cable or wiring, and wireless connection.

[0177] The power receiving terminal 210 and the communication terminal 216 may be configured to receive power and perform communication through the same terminal. Similarly, the power transmitting terminal 76A and the communication terminal 76B may be configured to transmit power and perform communication through the same terminal.

[0178] The control device 30 of the multicopter 100 can acquire information regarding the power required to operate the work machine 200 from the MCU 214 of the work machine 200 via the communication terminals 216 and 76B. Such information may include information regarding a plan for the operation of the work machine 200.

[0179] The control device 30 can generate and supply the power required for the operation of the work machine 200 based on information acquired from the work machine 200. Note that the work machine 200 does not need to be equipped with the MCU 214, and the control device 30 of the multicopter 100 may be configured to execute some or all of the functions of the MCU 214 of the work machine 200.

[0180] 15 is a block diagram showing an example of the hardware configuration of the control device 30. The control device 30 includes a processor 34, a ROM (Read Only Memory) 35, a RAM (Random Access Memory) 36, a storage device 37, and a communication I / F 38. These components are connected to each other via a bus 39.

[0181] The processor 34 is one or more semiconductor integrated circuits, and is also referred to as a central processing unit (CPU) or a microprocessor. The processor 34 sequentially executes computer programs stored in the ROM 35 to perform the above-described processing. The term "processor 34" is broadly interpreted as including a field programmable gate array (FPGA) equipped with a CPU, a graphic processor unit (GPU), an application specific integrated circuit (ASIC), or an application specific standard product (ASSP).

[0182] The ROM 35 is, for example, a writable memory (e.g., a PROM), a rewritable memory (e.g., a flash memory), or a read-only memory. The ROM 35 stores a program that controls the operation of the processor. The ROM 35 does not have to be a single recording medium, but may be a collection of multiple recording media. Some of the collection of multiple recording media may be removable memories.

[0183] The RAM 36 provides a working area for temporarily loading the programs stored in the ROM 35 at boot time. The RAM 36 does not have to be a single recording medium, but can be a collection of multiple recording media.

[0184] The communication I / F 38 is an interface for communication between the control device 30 and other electronic components or electronic control units (ECUs). For example, the communication I / F 38 can perform wired communication in accordance with various protocols. The communication I / F 38 may also perform wireless communication in accordance with the Bluetooth (registered trademark) standard and / or the Wi-Fi (registered trademark) standard. Both standards include wireless communication standards that use frequencies in the 2.4 GHz band.

[0185] The storage device 37 may be, for example, a semiconductor memory, a magnetic storage device, an optical storage device, or a combination thereof. The storage device 37 may store, for example, map data useful for the autonomous flight of the multicopter 10 and various sensor data acquired by the multicopter 10 during flight.

[0186] As described above, the control device 30 may include, for example, a flight control device such as the flight controller 32 and a higher-level computer (companion computer) as separate components. The companion computer may execute the processes described above and issue flight-related commands based on the results of those processes to the flight controller.

[0187] 16 , some or all of the functions of the control device 30 may be implemented by one or more servers (computers) 500 or terminal devices (including portable and fixed types) 400 connected to the communication device of the multicopter 100 via a communication network N. An agricultural machine 700 such as a tractor may be connected to such a communication network N, and communication may be performed between the multicopter 100 and the agricultural machine 700. Some of the data used for processing by the control device 30 and control signals for the multicopter 100 may be provided from the agricultural machine 700 to the multicopter 100 via the communication network N.

[0188] In the unmanned aerial vehicle according to the above embodiments, the "attitude control device" includes multiple electric motors, and the "main thrust generating device" includes an internal combustion engine. In other words, the unmanned aerial vehicle according to the above embodiments includes the rotary drive device 3D shown in FIG. 1A. However, even in the rotary drive devices 3A, 3B, and 3C shown in FIG. 1A, by differentiating some of the motors 14 or power transmission systems 23 from the other motors 14 or power transmission systems 23, it is possible to realize an unmanned aerial vehicle that includes an "attitude control device" and a "main thrust generating device."

[0189] The unmanned aerial vehicle may also be equipped with multiple internal combustion engines with different power outputs and response speeds. In this case, an internal combustion engine with a relatively low power output and a relatively high response speed may constitute an "attitude control device," and an internal combustion engine with a relatively high power output and a relatively low response speed may constitute a "main thrust generating device."

[0190] The unmanned aerial vehicle disclosed herein can be widely used not only for aerial photography, surveying, logistics, and pesticide spraying, but also for ground work related to agricultural work, transporting harvested products and agricultural materials, and the like.

[0191] 2: Rotor (propeller), 3: Rotation drive device, 4: Airframe body, 4a: Control device, 4b: Sensor group, 4c: Communication device, 5: Airframe frame, 10: Multicopter, 12: Sub-rotor, 12a: Propeller, 12b: Propeller, 14: Motor, 16: ESC, 22: Main rotor, 52: Battery, 54: Battery management device

Claims

1. 1. An unmanned aerial vehicle having multiple rotors, a power source; a power supply device that supplies external power from the power source to the work machine; An unmanned aerial vehicle comprising:

2. a plurality of electric motors that respectively drive a plurality of first rotors included in the plurality of rotors; a first wiring that supplies electric power from the power source to each of the electric motors; a second wiring branching from the first wiring and supplying the external power from the power source to the power supply device; The unmanned aerial vehicle of claim 1 , comprising:

3. The unmanned aerial vehicle according to claim 2 , wherein the power source includes a battery that stores a first power.

4. at least one second rotor included in the plurality of rotors; an internal combustion engine driving the at least one second rotor; a power generation device driven by the internal combustion engine to generate second electric power; Equipped with the power source includes the power generator; The unmanned aerial vehicle according to claim 2 or 3, wherein the power generation device is connected to the first wiring and the second wiring.

5. The unmanned aerial vehicle according to claim 1 , wherein the work machine is an exchangeable implement that performs agricultural work on a field or a crop in the field.

6. The unmanned aerial vehicle according to claim 1 , wherein the power supply device has a terminal for supplying power to the work machine and a terminal for communicating with the work machine.

7. a control device that controls the output of the external power from the power supply device, The unmanned aerial vehicle according to claim 6 , wherein the control device controls the supply of the external power in accordance with the current operating state or the planned operating state of the work machine obtained through the communication.

8. The unmanned aerial vehicle is configured to fly while towing the work machine, The unmanned aerial vehicle according to claim 1 , wherein the power supply device and the work machine are electrically connected by a cable.