Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B64—AIRCRAFT; AVIATION; COSMONAUTICS
  • B64U—UNMANNED AERIAL VEHICLES [UAV]; EQUIPMENT THEREFOR
  • B64U10/00—Type of UAV
  • B64U10/10—Rotorcrafts
  • B64U10/13—Flying platforms
  • B64U10/16—Flying platforms with five or more distinct rotor axes, e.g. octocopters
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B64—AIRCRAFT; AVIATION; COSMONAUTICS
  • B64U—UNMANNED AERIAL VEHICLES [UAV]; EQUIPMENT THEREFOR
  • B64U2101/00—UAVs specially adapted for particular uses or applications
  • B64U2101/40—UAVs specially adapted for particular uses or applications for agriculture or forestry operations

Definitions

• Unmanned aerial vehicles are aircraft that cannot accommodate people due to their structure, but can fly remotely or automatically.
• 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 are also called “drones,” “multirotors,” or “multicopters,” and are widely used for aerial photography, surveying, logistics, and pesticide spraying.
• Patent Document 1 describes an unmanned aerial vehicle (unmanned flying object) that changes its flight position in conjunction with the operation of agricultural machinery.
• Patent Document 2 describes an unmanned aerial vehicle (autonomous flying device) that can increase the payload and continuous flight time, and can accurately adjust its position and attitude during flight.
• autonomous flying device autonomous flying device
• the present disclosure provides an unmanned aerial vehicle capable of increasing payload and/or flight time and suitable for agricultural applications.
• the unmanned aerial vehicle of the present disclosure is an unmanned aerial vehicle having multiple rotors, further comprising a control device that controls the rotation of the multiple rotors, the multiple rotors including multiple first rotors and at least one second rotor, and the control device acquires information about the weight of the unmanned aerial vehicle and controls the rotational speed of at least one second rotor included in the multiple rotors based on the acquired information.
• the unmanned aerial vehicle and the control method for the unmanned aerial vehicle disclosed herein it is possible to realize an unmanned aerial vehicle that is suitable for agricultural applications and that can increase the payload and/or flight time.
• FIG. 1 is a block diagram showing an example of a basic configuration of a parallel hybrid type multicopter.
• FIG. 1 is a schematic top view of a multicopter in an exemplary embodiment;
• FIG. 1 is a side view diagrammatically illustrating a multicopter in an exemplary embodiment;
• FIG. 2 is a block diagram illustrating an example of a system configuration in a multicopter according to an exemplary embodiment.
• FIG. 1 is a plan view illustrating a parallel hybrid drive type multicopter.
• 10 is a flowchart showing an example of a process for determining the rotational speeds of each sub-rotor and each main rotor.
• 4 is a flowchart illustrating an example of a process performed by a control device.
• FIG. 4 is a flowchart illustrating an example of a process performed by a control device.
• 1 is a schematic diagram showing a change in the total thrust of the main rotor when the total weights of the multicopters are different from each other.
• FIG. 4 is a flowchart illustrating an example of a process performed by a control device.
• 1 is a schematic diagram showing a change in the total thrust of the main rotor when the total weights of the multicopters are different from each other.
• FIG. 4 is a flowchart showing an example of a method for controlling an electric motor and an internal combustion engine.
• FIG. 2 is a block diagram showing a configuration example of a flight controller.
• 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, making it possible to increase the efficiency of energy utilization.
• This type of drive is called a "parallel hybrid drive.”
• FIG. 1B is a plan view that shows a schematic example of one basic configuration of multicopter 10.
• the configuration example of FIG. 1B includes a first rotation drive device 3A shown in FIG. 1A as the rotation drive device 3. That is, the rotation drive device 3 (3A) in this example includes a motor 14 and a battery 52.
• FIG. 1C is a side view that shows a schematic example of multicopter 10.
• the multicopter 10 is a quad-type multicopter (quadcopter) equipped with four rotors 2.
• the rotors 2 located on one diagonal line rotate in the same direction (clockwise or counterclockwise), but the rotors 2 located on different diagonals rotate in the opposite direction.
• the aircraft body 4 includes a control device 4a that controls the operation of the 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.
• the control device 4a may include, for example, a flight control device such as a flight controller, and a higher-level computer (companion computer).
• the companion computer can perform advanced computational processing such as image processing, obstacle detection, and obstacle avoidance based on the sensor data acquired by the sensor group 4b.
• the sensor group 4b may include an acceleration sensor, an angular velocity sensor, a geomagnetic sensor, an air 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 GNSS (Global Navigation Satellite System) receiver.
• the acceleration sensor and the angular velocity sensor may be mounted on the aircraft body 4 as components of an IMU (Inertial Measurement Unit), for example.
• IMU Inertial Measurement Unit
• laser sensors may include a laser range finder used to measure the distance to the ground, and a two-dimensional or three-dimensional LiDAR (light detection and ranging).
• the communication device 4c may include a wireless communication module for transmitting and receiving signals via an antenna between a transmitter on the ground or a ground station (Ground Control Station: GCS), a mobile communication module using a cellular communication network, and the like.
• 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 function for satellite communication.
• 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 executed by a computer on the cloud.
• the configuration of the rotation drive device 3 may include a rotor 2 with a relatively large thrust that can be generated and a rotor 2 with a relatively small thrust.
• the rotor 2 with a relatively large thrust that can be generated may be referred to as the "main rotor” and the rotor 2 with a relatively small thrust may be referred to as the "sub rotor”.
• the rotor 2 that generates a relatively large thrust per rotation may be called the "main rotor”
• the rotor 2 that generates a relatively small thrust per rotation may be called the "sub-rotor.”
• the main rotor may be positioned more inward than the sub-rotor.
• each rotor 2 may be positioned so that the distance from the center of the aircraft to the rotation axis of each main rotor is shorter than the distance from the center of the aircraft to the rotation axis of each sub-rotor.
• the eight propellers 12a and 12b of the sub-rotor 12 have the same pitch angle and diameter as each other.
• 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.
• the multicopter 100 in this embodiment includes eight sub-rotors 12, eight motors 14 that rotate the eight sub-rotors 12, and eight ESCs that control the eight motors 14.
• Each ESC 16 receives a signal (motor control signal) for controlling the motor 14 from the control device 30 via the wiring 82.
• the motor control signal is, for example, a PWM (Pulse With Modulation) signal.
• PWM Pulse With Modulation
• the duty 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 the ESC 16 based on the motor control signal from the control device 30. In FIG.
• 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 opening.
• 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.
• Mechanical devices such as a clutch and a reducer may be provided between the main rotor drive unit 24 and the main rotor 22.
• the battery 52 can receive DC power from the power generation device 42 via a power switch 56 and be charged by that power.
• the operation of the power switch 56 can be controlled by the battery management device 54 and the control device 30.
• the battery management device 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, charging rate (State Of Charge: SOC), state of health (State Of Health: SOH), and temperature.
• the storage capacity of the battery 52 has a value that allows the aircraft to continue to generate lift and control attitude by the sub-rotor 12 and fly to a location where landing is possible and land there, even if power generation by the power generation device 42 stops for some reason and lift by the main rotor 22 is lost.
• the power required to drive the sub-rotor 12 can be supplied to the ESC 16 from the power generation device 42, not from the battery 52. For this reason, even if the payload and flight time are increased, there is little need to increase the storage capacity of the battery 52 accordingly.
• an internal combustion engine can efficiently generate a large thrust.
• the sub-rotor 12 is rotated using electricity generated by the power of the main rotor drive unit 24, which is an internal combustion engine, but energy losses occur when converting mechanical energy into electrical energy. For this reason, from the perspective of improving energy consumption efficiency, it is preferable that the main rotor drive unit 24 is used to rotate the main rotor 22 to generate the main thrust. Also, in order to increase the thrust of the main rotor 22, it is preferable that the diameter of the main rotor 22 is larger than the diameter of each of the multiple sub-rotors 12.
• battery-powered multicopters use various algorithms to adjust the torque of each of the multiple motors to adjust the thrust of each rotor and control it to the desired attitude.
• adding a rotor rotated by an internal combustion engine can complicate the calculations required for attitude control.
• FIG. 5 is a plan view showing a parallel hybrid drive type multicopter 100.
• FIG. 5 shows an xyz coordinate system defined by mutually orthogonal x-, y-, and z-axes. This coordinate system is fixed to the body of the multicopter 100, and its origin is located at the center of the body (e.g., the center of gravity).
• the x-axis is an axis that extends forward of the body and is also called the “roll axis.”
• the y-axis is an axis that extends leftward of the body and is also called the "pitch axis.”
• the z-axis is an axis that extends upward of the body and is also called the "yaw axis.”
• each main rotor 22 The distance from the center of the aircraft to the rotation axis of each main rotor 22 is shorter than the distance from the center of the aircraft to the rotation axis of each sub-rotor 12.
• the diameter of each main rotor 22 is larger than the diameter of each sub-rotor 12. 5
• each main rotor 22 is represented by a relatively large circle
• the two coaxial sub-rotors 12 are represented by one relatively small circle.
• the main rotor 22 supported by the arm 110B1 extending from the center of the aircraft in the positive direction of the x-axis rotates clockwise at a rotational speed of ⁇ m1 .
• the main rotor 22 supported by the arm 110B2 extending from the center of the aircraft in the negative direction of the x-axis rotates counterclockwise at a rotational speed of ⁇ m2 .
• each of the four arms 110A1, 110A2, 110A3, 110A4 supporting the sub-rotor 12 is l
• the length of each of the two arms 110B1, 110B2 supporting the main rotor 22 is l m .
• the total thrust generated by the rotation of the multiple main rotors 22 and the multiple sub-rotors 12 is T
• the torque of rotation about the x-axis is ⁇ ⁇
• the torque of rotation about the y-axis is ⁇ ⁇
• the torque of rotation about the z-axis is ⁇ ⁇ .
• T-2k m ⁇ m 2 can be calculated by multiplying T by a constant coefficient. For example, if the ratio between the total thrust of the main rotor 22 and the total thrust of the sub-rotor 12 is fixed at 6:4, T-2k m ⁇ m 2 can be determined by multiplying T by a coefficient of 0.4. Also, if the ratio between the total thrust of the main rotor 22 and the total thrust of the sub-rotor 12 is fixed at, for example, 3:7, T-2k m ⁇ m 2 can be determined by multiplying T by a coefficient of 0.7.
• the total thrust 2k m ⁇ m 2 by the main rotor 22 can be calculated by multiplying the total thrust T by all rotors or the total thrust T-2k m ⁇ m 2 by the sub-rotor 12 by a predetermined coefficient. Since km is known, the rotational speed ⁇ m of the main rotor 22 can be calculated from the value of 2k m ⁇ m 2 .
• step S100 the control device 30 acquires information about the total weight T 0 of the multicopter 100.
• the information about the total weight T 0 of the multicopter 100 may be stored in advance in a storage device, for example.
• the weight of the multicopter 100 may be stored in advance in a storage device, and the weight of the working machine 200 may be measured by a sensor. By providing such a sensor, the total weight T 0 of the multicopter 100 can be estimated more accurately even if the weight of the working machine 200 varies due to work such as pesticide spraying or harvesting.
• control device 30 may calculate the weight of the fuel or the change amount thereof by detecting the remaining amount of fuel in the internal combustion engine (main rotor drive unit 24) from, for example, a sensor (level sensor) provided in a container (fuel tank) that contains the fuel.
• the control device 30 may calculate the total weight T 0 of the multicopter 100 based on data acquired from the storage device and/or the sensor.
• the control device 30 determines the sum (total thrust) T of the thrust to be generated by the multiple sub-rotors 12 and the multiple main rotors 22.
• the control device 30 can determine the total thrust T based on information on the total weight T0 of the multicopter 100 and the flight state. For example, during hovering, the control device 30 can determine the thrust that balances the total weight T0 of the multicopter 100 as the total thrust T.
• the control device 30 can determine the total thrust T based on the condition that the vertical component of the thrust balances with gravity, taking into account the inclination of the aircraft.
• the control device 30 determines the total thrust T so that the aircraft ascends or descends with the desired acceleration.
• step S104 the control device 30 estimates the current attitude angle of the multicopter 100 based on data acquired from one or more sensors, such as the IMU and a geomagnetic sensor.
• the attitude angle represents the inclination of the multicopter 100 from a reference attitude in a coordinate system fixed to the ground.
• steps S104 and S106 may be performed before the processes of steps S100 and S102, or may be performed in parallel.
• step S108 the control device 30 determines a first thrust T1, which is the total thrust to be generated by the multiple sub-rotors 12, by multiplying the total thrust T determined in step S102 by a first coefficient K1, which is equal to or greater than 0 and equal to or less than 1.
• the first coefficient K1 can be set to a predetermined value, for example, 0.4.
• the calculation of multiplying the total thrust T by the second coefficient K2 and the calculation of multiplying the first thrust T1 by the third coefficient K3 bring about the same result.
• steps S108 and S110 are not particularly limited, and either may be performed first, or these processes may be performed simultaneously.
• the ratio between the second thrust T2 , which is the total thrust of the main rotor 22, and the first thrust T1 , which is the total thrust of the sub rotor 12, may be set to a predetermined ratio, for example, 6:4.
• the third coefficient corresponds to T2 / T1 , and may be referred to as the "boost coefficient.”
• the first thrust force T 1 corresponds to T ⁇ 2 km ⁇ m 2 in Equation 4
• the second thrust force T 2 corresponds to 2 km ⁇ m 2 in Equation 4.
• steps S112 and S114 are not particularly limited, and either may be performed first, or these processes may be performed simultaneously.
• the control device 30 can determine the rotational speed of each rotor based on the desired total thrust T and the required torques ⁇ ⁇ , ⁇ ⁇ , and ⁇ ⁇ around each axis. Note that instead of the processing in step S110 described above, the control device 30 may calculate the second thrust T2 by subtracting the first thrust T1 from the total thrust T required for flight. The second thrust T2 can also be obtained by such a calculation.
• the control device 30 controls each motor 14 and the internal combustion engine (main rotor drive unit 24) based on the determined rotational speed of each sub-rotor 12 and each main rotor 22.
• the control device 30 controls each motor 14 via each ESC 16 by sending a motor control signal (e.g., a PWM signal) indicating the determined rotational speed of the sub-rotor 12 to each ESC 16.
• the control device 30 also controls the internal combustion engine via the main rotor control unit 26 by sending a control signal indicating the determined rotational speed of the main rotor 22 to the main rotor control unit 26.
• the above operations are executed repeatedly during flight.
• the control device 30 in this embodiment calculates the first thrust T1 , which is the total thrust generated by the multiple sub-rotors 12, and calculates the second thrust T2 , which is the total thrust generated by the main rotor 22 , based on the first thrust T1 and the total thrust T required for flight.
• the control device 30 determines the rotational speeds ⁇ 1 to ⁇ 8 of each of the multiple sub-rotors 12 based on the first thrust T1 , and determines the rotational speed ⁇ m of each main rotor 22 based on the second thrust T2 .
• control device 30 determines the total thrust T to be generated by the multiple sub-rotors 12 (first rotors) and the multiple main rotors 22 (second rotors), and can determine the rotational speed of each rotor based on a predetermined relationship between the total thrust T and the rotational speed ⁇ m of the main rotor 22 and/or a predetermined relationship between the total thrust T and the rotational speeds ⁇ 1 to ⁇ 8 of each of the sub-rotors 12. These predetermined relationships are expressed by, for example, at least one or all of a first coefficient K1 , a second coefficient K2 , and a third coefficient K3 .
• control device 30 can sequentially determine the rotational speed of each sub-rotor 12 and each main rotor 22 during flight, and rotate each sub-rotor 12 and each main rotor 22 at the determined rotational speed. This allows the multicopter 100 to approach the target attitude and perform the desired flight.
• the multicopter 100 has two main rotors 22 and eight sub-rotors 12, but the number of main rotors 22 and sub-rotors 12 is not limited to this example.
• the number of main rotors 22 may be one or three or more.
• the number of sub-rotors 12 may be another number, such as four or six.
• the sub-rotors 12 are not limited to the octo-quadcopter configuration shown in Figures 3A and 5, and various configurations such as a quadcopter, hexacopter, or octocopter can be adopted.
• the first coefficient K 1 and the second coefficient K 2 or the third coefficient K 3 may be variable.
• the boost coefficient T 2 /T 1 (corresponding to the third coefficient K 3 ), which is the ratio of the total thrust T 2 by the main rotor 22 to the total thrust T 1 by the sub rotor 12, may be variable.
• the boost coefficient corresponds to the ratio of the total thrust (second thrust) of the main rotor 22 obtained from the main rotor drive unit 24 to the total thrust (first thrust) of the sub rotor 12 obtained from the multiple motors 14.
• the control device 30 may change the first coefficient K 1 and the second coefficient K 2 or the third coefficient K 3 depending on the state of the multicopter 100.
• the control device 30 may change the first coefficient K 1 and the second coefficient K 2 or the third coefficient K 3 depending on the flight mode.
• the flight modes include, for example, modes such as hovering, horizontal flight (forward, backward, or sideways (aileron)), ascent, descent, and rotation (rudder).
• the control device 30 may be configured to maintain the first coefficient K 1 at a value smaller than 0.5, for example, during ascent and hovering.
• the first coefficient K 1 is maintained at a value smaller than 0.5
• the second coefficient K 2 is maintained at a value larger than 0.5
• the third coefficient K 3 boost coefficient
• the control device 30 may set the boost coefficient to a value smaller than the value during hovering (for example, a value smaller than 1). This allows a large thrust and rotational moment generated by the rotation of the main rotor 22 to be suppressed from interfering with the attitude control by the sub rotor 12.
• the total weight T 0 of the multicopter 100 is the total weight of the weight of the multicopter 100 and the weight of the load (here, the work machine 200) connected to the body 121 of the multicopter 100.
• the weight of the multicopter 100 may include the body weight of the multicopter 100 and the weight of the fuel for the internal combustion engine.
• the weight of the multicopter 100 excluding the load and the fuel may be referred to as the "body weight".
• the control device 30 executes the processing shown in Fig. 7 while the multicopter 100 is flying, thereby changing the rotation speed of each rotor in response to a change in the total weight T0 of the multicopter 100.
• the control of the attitude angle of the multicopter 100 is omitted in Fig. 7, but can be performed in a similar manner to the method described with reference to Fig. 6.
• step S200 the control device 30 determines whether or not to start control based on a change in the total weight T 0 of the multicopter 100.
• the control device 30 determines whether or not to start control based on a change in weight based on, for example, a command from an external device such as a pilot or a remote monitoring device used by a user, or a preset flight plan. The determination may be made during the flight of the multicopter 100.
• the rotation speed of the main rotor 22 and the rotation speed of the sub rotor 12 and the attitude angle of the multicopter 100 may be controlled by, for example, the method described with reference to FIG. 6. If it is determined that the control based on a change in the total weight T 0 of the multicopter 100 is to be started (in the case of "Yes"), the process proceeds to step S202.
• step S202 the control device 30 detects a change in the total weight T0 of the multicopter 100 while the multicopter 10 is flying.
• the control device 30 can detect a change in the weight of the work machine 200 by, for example, measuring the weight of the work machine 200 with a sensor while the multicopter 100 is flying.
• the control device 30 may calculate the weight of the fuel or the change in the weight of the work machine 200 with a sensor provided in the fuel tank.
• the method is not limited to using a sensor, and the control device 30 can also detect a change in the total weight T0 of the multicopter 100 by estimating the change (decrease) in the fuel and the change in the agricultural materials or harvested products stored in the work machine 200 from the flight time, flight distance, work content, work time, etc. of the multicopter 100 .
• the control device 30 may determine the rotation speeds of the main rotor 22 and the sub rotor 12 so that the ratio between the second thrust T2 and the first thrust T1 is within a predetermined range, allowing a predetermined error (e.g., ⁇ 5%), without being limited to the case where the ratio between the second thrust T2 and the first thrust T1 strictly matches the predetermined ratio.
• the control device 30 may determine the rotation speed of the main rotor 22 based on data such as a table showing the relationship between the total thrust T determined based on the total weight T0 of the multicopter 100 and the rotation speed of the main rotor 22.
• the control device 30 changes the rotation speed of the sub-rotor 12 in accordance with the amount of change in the total weight T0 of the multicopter 100 in step S208, and maintains the rotation speed of the main rotor 22 unchanged.
• the control device 30 can determine the rotation speed of the sub-rotor 12 based on the total thrust T determined based on the total weight T0 of the multicopter 100 and the rotation speed of the main rotor 22. Since the rotation speed of the main rotor 22 is maintained, there is no need to change the target rotation speed of the engine.
• the rotation speed of the rotor can be controlled in accordance with the change in the total weight T0 of the multicopter 100 while suppressing the frequency of changing the target rotation speed of the internal combustion engine (main rotor drive unit 24), thereby controlling the flight of the multicopter 100.
• the control device 30 repeats the processing of steps S202, S204, S206, and S208 while the multicopter 100 is flying until an end command is issued (step S210).
• the control device 30 can control flight in response to a change in the total weight T 0 of the multicopter 100. For example, when work is performed by the work machine 200 connected to the multicopter 100, the control device 30 can respond to a change in the weight of the work machine 200.
• "when a change in the total weight T 0 of the multicopter 100 is detected" includes not only a case where the total weight T 0 of the multicopter 100 has actually changed, but also a case where there is a difference between the information on the total weight T 0 of the multicopter 100 used to determine the rotation speed of the main rotor 22 or the sub rotor 12 (for example, the information on the total weight T 0 of the multicopter 100 acquired in step S100 of FIG.
• the process described with reference to FIG. 7 can be performed to perform control based on the corrected total weight T 0 of the multicopter 100.
• step S100 of FIG. 6 information on the total weight T 0 of the multicopter 100 may be acquired as information on the total weight T 0 of the multicopter 100, which is the total weight of the multicopter 100's body weight and the weight of the load (here, the work machine 200).
• the weight of the multicopter 100 does not change during flight.
• the weight of the multicopter 100 is known to the user and can be stored in a storage device in advance.
• the total weight T 0 of the multicopter 100 is the total of the weight of the multicopter 100's body weight, the weight of the fuel, and the weight of the load (here, the work machine 200).
• the total weight of the weight of the multicopter 100's body weight and the weight of the work machine 200 may not match the total weight T 0 of the multicopter 100, but by performing the processing described with reference to FIG. 7, processing based on the total weight T 0 of the multicopter 100 calculated by a sensor or the like can be performed. Therefore, in order to simplify control, the initial setting of the rotational speed of the main rotor 22 or the sub-rotor 12 can be performed using only information on the weight of the multicopter 100 and the weight of the work machine 200, which are known to the user.
• the control device 30 determines whether to perform the process of step S206 or step S208 depending on the magnitude of the change in the total weight T0 of the multicopter 100.
• the embodiment of the present disclosure is not limited to the example of FIG. 7.
• Another example of the process performed by the control device 30 will be described with reference to FIG. 8A and FIG. 9A.
• the control device 30 performs the process of step S206 when a change in the weight of the work machine 200 is detected, and performs the process of step S208 when no change in the weight of the work machine 200 is detected and only a change in the weight of the fuel is detected.
• the control device 30 may always perform the process of step S206 when a change in the total weight T0 of the multicopter 100 is detected.
• step S224 the control device 30 determines whether or not a change in the weight of the work machine 200 is detected. If a change in the weight of the work machine 200 is detected (if "Yes"), in step S226, the control device 30 changes the rotation speed of the main rotor 22 and the rotation speed of the sub-rotor 12 according to the amount of change in the total weight T0 of the multicopter 100. Step S226 may be performed in the same manner as step S206 in FIG. 7.
• both the weight of the payload and the weight of the fuel change.
• the control device 30 changes the rotation speed of the main rotor 22 and the rotation speed of the sub rotor 12 while maintaining the ratio between the second thrust T 2 and the first thrust T 1 unchanged.
• the multicopter 100 in this embodiment has multiple rotors including multiple sub-rotors 12 and at least one main rotor 22.
• the multiple sub-rotors 12 are each driven by multiple motors 14.
• At least one main rotor 22 is driven by a main rotor drive unit 24, i.e., an internal combustion engine.
• the control device 30 controls the rotation of the multiple sub-rotors 12 by controlling the multiple motors 14, thereby performing attitude control of the aircraft.
• the control device 30 controls the rotation of at least one main rotor 22 by controlling the internal combustion engine via the main rotor control unit 26, thereby generating main thrust.
• PWM signals #1 to #8 are also input to a module 326 that generates a PWM signal for the main rotor 22.
• Module 326 generates a PWM signal (second PWM signal) for the main rotor 22 based on these PWM signals #1 to #8, and outputs the second PWM signal to the main rotor control unit 26.
• the main rotor control unit 26 converts the second PWM signal into a second control signal, which is an engine control signal, and controls the internal combustion engine based on the second control signal.
• Processor 34 is one or more semiconductor integrated circuits, and is also called a central processing unit (CPU) or microprocessor. Processor 34 sequentially executes computer programs stored in ROM 35 to realize the above-mentioned processing. Processor 34 is broadly interpreted as a term including a CPU-equipped FPGA (Field Programmable Gate Array), GPU (Graphic Processor Unit), ASIC (Application Specific Integrated Circuit), or ASSP (Application Specific Standard Product).
• CPU CPU-equipped FPGA
• GPU Graphic Processor Unit
• ASIC Application Specific Integrated Circuit
• ASSP Application Specific Standard Product

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• 2022
  • 2022-12-27 WO PCT/JP2022/048186 patent/WO2024142243A1/ja active Application Filing
  • 2022-12-27 JP JP2024567026A patent/JPWO2024142243A1/ja active Pending

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