Aircraft control devices
The control device adjusts rotor blade pitch and stop rotation angle to manage lift and drag forces on the airframe, addressing inefficiencies in stationary rotor control and enhancing aircraft performance.
Patent Information
- Application Number
- JP2022158019
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2022-09-30
- Publication Date
- 2026-01-07
- Estimated Expiration
- 2042-09-30
AI Technical Summary
Existing aircraft control systems using stationary rotors struggle with effective force control on the airframe when the rotor is stopped, leading to inefficiencies in managing lift and drag.
A control device that adjusts the pitch and stop rotation angle of each rotor blade to manage lift and drag forces, even when the rotors are stationary, by differentiating force application based on the rotor's position relative to the aircraft's center of gravity.
Enhances control over airframe forces, improves response speed, and reduces energy consumption by optimizing lift, drag, and moment generation, even when rotors are not rotating.
Smart Images

Figure 0007795441000001 
Figure 0007795441000002 
Figure 0007795441000003
Abstract
Description
[Technical Field]
[0001] The present invention relates to a control device for an aircraft. [Background technology]
[0002] Patent Document 1 below discloses an aircraft control device. The aircraft has a rotor that generates lift by rotating, separate from wings that generate lift. The control device optimizes the position of the rotor blades during cruising, thereby minimizing turbulence in the airflow over the wings during cruising. [Prior art documents] [Patent documents]
[0003] [Patent Document 1] US Patent Application Publication No. 2020 / 0079501 Summary of the Invention [Problem to be solved by the invention]
[0004] Better control is required when using forces generated in a stationary rotor to control forces acting on the airframe.
[0005] The present invention aims to solve the above-mentioned problems. [Means for solving the problem]
[0006] One aspect of the present invention is a control device for an aircraft having a plurality of rotors, each having one or more blades and generating lift by rotating around a rotating shaft, and one or more fixed wings that generate lift when the aircraft has airspeed, wherein the control device applies a force to the aircraft by controlling the pitch of each of the blades and the stopping rotation angle of each of the rotors when lift is generated in the fixed wings, and controlling the force generated in each of the rotors when the rotation of the rotors is stopped. [Effects of the Invention]
[0007] The present invention provides better control of the forces acting on the airframe using the forces generated in the rotor when the rotor is stopped. [Brief explanation of the drawings]
[0008] [Figure 1] Figure 1 is a schematic diagram of an aircraft. [Figure 2] FIG. 2 is a diagram showing the configuration of the power supply system. [Figure 3] FIG. 3 is a block diagram of the control device. DETAILED DESCRIPTION OF THE INVENTION
[0009] [First embodiment] [Aircraft configuration] FIG. 1 is a schematic diagram of an aircraft 10. The aircraft 10 of this embodiment is an electric vertical take-off and landing aircraft (eVTOL aircraft). The aircraft 10 of this embodiment has multiple VTOL rotors 12 and multiple cruise rotors 14. The rotation of the VTOL rotors 12 generates lift that moves the airframe 16 upward. The rotation of the cruise rotor 14 generates thrust that moves the airframe 16 forward.
[0010] The aircraft 10 has a fuselage 16. The fuselage 16 is provided with a cockpit, a cabin, etc. A pilot sits in the cockpit and pilots the aircraft 10. The cabin houses passengers, etc. The aircraft 10 may be piloted automatically without a pilot on board.
[0011] The aircraft 10 has fixed wings, that is, front wings 18 and rear wings 20. The front wings 18 are provided forward of the center of gravity G of the fuselage 16. The rear wings 20 are provided rearward of the center of gravity G of the fuselage 16. When the fuselage 16 has an airspeed, the angles of attack of the front wings 18 and rear wings 20 are controlled, thereby generating lift on the front wings 18 and rear wings 20.
[0012] Ailerons, elevators, and rudder (not shown) are provided on at least one of the front wings 18 and rear wings 20. When the ailerons are operated, a roll moment acts around the center of gravity G of the aircraft 16. When the elevators are operated, a pitch moment acts around the center of gravity G of the aircraft 16. When the rudder is operated, a yaw moment acts around the center of gravity G of the aircraft 16.
[0013] The aircraft 10 has eight VTOL rotors 12. The eight VTOL rotors 12 are rotor 12FLa, rotor 12FLb, rotor 12RLa, rotor 12RLb, rotor 12FRa, rotor 12FRb, rotor 12RRa, and rotor 12RRb. Each of the VTOL rotors 12 corresponds to a rotor of the present invention.
[0014] The rotors 12FLa, 12FLb, 12RLa, and 12RLb are attached to a boom 22L. The boom 22L extends in the front-to-rear direction. The boom 22L is attached to the front wing 18 and the rear wing 20. The boom 22L is provided to the left of the center of gravity G. In other words, the rotors 12FLa, 12FLb, 12RLa, and 12RLb are disposed to the left of the center of gravity G.
[0015] The rotor 12FLa is provided forward of the front wing 18. The rotor 12FLb is provided between the front wing 18 and the center of gravity G in the longitudinal direction of the fuselage 16. The rotor 12RLb is provided between the center of gravity G and the rear wing 20 in the longitudinal direction of the fuselage 16. The rotor 12RLa is provided rearward of the rear wing 20. The distance from the center of gravity G to the rotor 12FLb is shorter than the distance from the center of gravity G to the rotor 12FLa. The distance from the center of gravity G to the rotor 12RLb is shorter than the distance from the center of gravity G to the rotor 12RLa.
[0016] The rotor 12FLa corresponds to the outer rotor and the first rotor of the present invention. The rotor 12FLb corresponds to the inner rotor and the second rotor of the present invention. The rotor 12RLb corresponds to the inner rotor and the third rotor of the present invention. The rotor 12RLa corresponds to the outer rotor and the fourth rotor of the present invention.
[0017] The rotors 12FRa, 12FRb, 12RRa, and 12RRb are attached to a boom 22R. The boom 22R extends in the fore-and-aft direction. The boom 22R is attached to the front wing 18 and the rear wing 20. The boom 22R is provided to the right of the center of gravity G. In other words, the rotors 12FRa, 12FRb, 12RRa, and 12RRb are disposed to the right of the center of gravity G.
[0018] The rotor 12FRa is provided forward of the front wing 18. The rotor 12FRb is provided between the front wing 18 and the center of gravity G in the longitudinal direction of the fuselage 16. The rotor 12RRb is provided between the center of gravity G and the rear wing 20 in the longitudinal direction of the fuselage 16. The rotor 12RRa is provided rearward of the rear wing 20. The distance from the center of gravity G to the rotor 12FRb is shorter than the distance from the center of gravity G to the rotor 12FRa. The distance from the center of gravity G to the rotor 12RRb is shorter than the distance from the center of gravity G to the rotor 12RRa.
[0019] The rotor 12FRa corresponds to the outer rotor and first rotor of the present invention. The rotor 12FRb corresponds to the inner rotor and second rotor of the present invention. The rotor 12RRb corresponds to the inner rotor and third rotor of the present invention. The rotor 12RRa corresponds to the outer rotor and fourth rotor of the present invention.
[0020] 1, the boom 22L and the boom 22R have a shape that extends linearly in the fore-and-aft direction of the airframe 16. However, the boom 22L and the boom 22R may be formed in an arc shape that convex outward in the left-and-right direction of the airframe 16. When the boom 22L is formed in an arc shape that convex outward in the left-and-right direction of the airframe 16, the rotor 12FLb is located to the left (outside) of the rotor 12FLa in the left-and-right direction of the airframe 16. When the boom 22R is formed in an arc shape that convex outward in the left-and-right direction of the airframe 16, the rotor 12FRb is located to the right (outside) of the rotor 12FRa in the left-and-right direction of the airframe 16.
[0021] Each of the VTOL rotors 12 has a rotation shaft 24. The rotation shaft 24 extends in the vertical direction of the airframe 16. The rotation shaft 24 may be angled (canted) by several degrees relative to the vertical direction of the airframe 16.
[0022] Each of the VTOL rotors 12 has three blades 26. The number of blades 26 of the VTOL rotor 12 does not have to be limited to three. The number of blades 26 of the VTOL rotor 12 may be one or more.
[0023] Lift is generated in the blades 26 as the VTOL rotor 12 rotates around the rotary shaft 24. The magnitude of lift generated in the VTOL rotor 12 is controlled by controlling the rotation speed and the pitch of the blades 26 of the VTOL rotor 12. The VTOL rotor 12 rotates and generates lift mainly during vertical takeoff, transition from vertical takeoff to cruising, transition from cruising to vertical landing, vertical landing, hovering in the air, etc.
[0024] When viewed from above the aircraft 10, the rotors 12FLa, 12RLa, 12FRb, and 12RRb rotate counterclockwise. When viewed from above the aircraft 10, the rotors 12FRa, 12RRa, 12FLb, and 12RLb rotate clockwise. Note that the rotation direction of each VTOL rotor 12 does not have to be limited to the above-described direction.
[0025] When the airframe 16 has airspeed, lift is generated in the VTOL rotor 12 even when the VTOL rotor 12 is stopped from rotating. The magnitude of lift generated in the VTOL rotor 12 is controlled by controlling the stopping rotation angle and the pitch of the blades 26 of the VTOL rotor 12. The magnitude of drag generated in the VTOL rotor 12 is controlled by controlling the stopping rotation angle and the pitch of the blades 26 of the VTOL rotor 12. For example, during cruising, the magnitude of lift and drag generated in the VTOL rotor 12 is controlled when the VTOL rotor 12 is stopped from rotating. Note that the magnitude of lift and drag generated in the VTOL rotor 12 may be controlled when the VTOL rotor 12 is stopped from rotating, not only during cruising but also during transition from vertical takeoff to cruising, transition from cruising to vertical landing, etc. Furthermore, when the airframe 16 has airspeed and lift is generated in the front wings 18 and the rear wings 20, the magnitude of lift and drag generated in the VTOL rotor 12 may be controlled when the VTOL rotor 12 is stopped from rotating.
[0026] By controlling the magnitude of lift and drag generated in each of the eight VTOL rotors 12, a roll moment, a pitch moment, and a yaw moment are applied around the center of gravity G of the aircraft 16.
[0027] By creating a difference between the sum of the lifts of the four VTOL rotors 12 arranged to the left of the center of gravity G and the sum of the lifts of the four VTOL rotors 12 arranged to the right of the center of gravity G, a roll moment acts around the center of gravity G of the aircraft 16.
[0028] The four VTOL rotors 12 arranged to the left of the center of gravity G refer to rotor 12FLa, rotor 12FLb, rotor 12RLa, and rotor 12RLb. The four VTOL rotors 12 arranged to the right of the center of gravity G refer to rotor 12FRa, rotor 12FRb, rotor 12RRa, and rotor 12RRb.
[0029] A pitch moment acts around the center of gravity G of the aircraft 16 by creating a difference between the sum of the lifts of the four VTOL rotors 12 arranged forward of the center of gravity G and the sum of the lifts of the four VTOL rotors 12 arranged aft of the center of gravity G.
[0030] The four VTOL rotors 12 arranged forward with respect to the center of gravity G refer to rotor 12FLa, rotor 12FLb, rotor 12FRa, and rotor 12FRb. The four VTOL rotors 12 arranged rearward with respect to the center of gravity G refer to rotor 12RLa, rotor 12RLb, rotor 12RRa, and rotor 12RRb.
[0031] By creating a difference between the sum of the drag on each of the four VTOL rotors 12 arranged to the left of the center of gravity G and the sum of the drag on each of the four VTOL rotors 12 arranged to the right of the center of gravity G, a yaw moment acts around the center of gravity G of the aircraft 16.
[0032] The aircraft 10 has two cruise rotors 14. The two cruise rotors 14 are rotor 14L and rotor 14R.
[0033] The rotors 14L and 14R are attached to the rear of the airframe 16. The rotor 14L is disposed to the left of the center line A of the airframe 16. The rotor 14R is disposed to the right of the center line A of the airframe 16.
[0034] The rotating shafts (not shown) of the cruise rotors 14 extend in the fore-and-aft direction of the airframe 16. The rotating shafts of the cruise rotors 14 may be angled (canted) by several degrees relative to the fore-and-aft direction. Each cruise rotor 14 has one or more blades (not shown).
[0035] The cruise rotor 14 rotates around the rotating shaft, generating thrust from its blades. The magnitude of thrust is controlled by controlling the rotation speed and blade pitch of the cruise rotor 14. The cruise rotor 14 rotates and generates thrust mainly during the transition from vertical takeoff to cruising, during cruising, and during the transition from cruising to vertical landing.
[0036] [Power supply system configuration] FIG. 2 is a diagram showing the configuration of the power supply system 28. As shown in FIG.
[0037] Each of the VTOL rotors 12 is provided with a drive mechanism including a VTOL motor 30, an inverter 32, and a pitch drive mechanism 34.
[0038] The VTOL motor 30 is PWM controlled by an inverter 32. This controls the rotation speed of the VTOL rotor 12. The pitch drive mechanism 34 changes the pitch of the blades 26 of the VTOL rotor 12.
[0039] Furthermore, the VTOL motor 30 is PWM controlled to control the stop rotation angle of the VTOL rotor 12. The VTOL rotor 12 maintains a predetermined rotation angle in a rotation-stopped state. The stop rotation angle indicates the predetermined rotation angle that is maintained. In order to maintain the VTOL rotor 12 stopped at the stop rotation angle, the inverter 32 controls the VTOL motor 30 to output a balancing torque against the external force.
[0040] The VTOL motor 30 is supplied with power at a relatively high voltage of several hundred volts output from a power supply unit 36. The power output from the power supply unit 36 is stepped down to a relatively low voltage of several tens of volts by a DC / DC converter 38 and then supplied to the pitch drive mechanism 34.
[0041] Each cruise rotor 14 is provided with a cruise motor 40, an inverter 42, and a pitch drive mechanism 44 as a drive mechanism.
[0042] The cruise motor 40 is PWM controlled by an inverter 42, thereby controlling the rotation speed of the cruise rotor 14. A pitch drive mechanism 44 changes the pitch of the blades of the cruise rotor 14.
[0043] The cruise motor 40 is supplied with power at a relatively high voltage of several hundred volts output from the power supply unit 36. The power output from the power supply unit 36 is stepped down to a relatively low voltage of several tens of volts by a DC / DC converter 46 and then supplied to the pitch drive mechanism 44.
[0044] The power supply unit 36 includes an engine, a generator, a power control unit, a battery, and the like, all of which are not shown. The engine drives the generator, which generates electricity. The power control unit converts the AC power generated by the generator into DC power and outputs it. The battery stores a portion of the power output from the power control unit. The battery outputs power when, for example, the power generated by the generator is insufficient to cover the power consumed by the VTOL motor 30, cruise motor 40, and the like.
[0045] The power supply unit 36 may have an engine, a generator, and a power control unit, but may not have a battery. The power supply unit 36 may have a battery, but may not have an engine, a generator, and a power control unit.
[0046] The inverter 32 , the pitch drive mechanism 34 , the inverter 42 and the pitch drive mechanism 44 are controlled by a control device 48 .
[0047] [Control device configuration] 3 is a block diagram of the control device 48. The control device 48 includes a calculation unit 50 and a storage unit 52.
[0048] The calculation unit 50 is a processor such as a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), etc. The calculation unit 50 has a lift command value calculation unit 54, a roll moment command value calculation unit 56, a pitch moment command value calculation unit 58, a yaw moment command value calculation unit 60, a mode selection unit 62, a thrust command value calculation unit 64, an allocation command value calculation unit 66, a control surface control command value generation unit 68, a control surface control unit 70, a VTOL rotor command value generation unit 72, a VTOL motor control unit 74, a pitch control unit 76, a cruise rotor command value generation unit 78, a cruise motor control unit 80, and a pitch control unit 82.
[0049] The lift command value calculation unit 54, the roll moment command value calculation unit 56, the pitch moment command value calculation unit 58, the yaw moment command value calculation unit 60, the mode selection unit 62, the thrust command value calculation unit 64, the allocation command value calculation unit 66, the control surface control command value generation unit 68, the control surface control unit 70, the VTOL rotor command value generation unit 72, the VTOL motor control unit 74, the pitch control unit 76, the cruise rotor command value generation unit 78, the cruise motor control unit 80, and the pitch control unit 82 are realized by the calculation unit 50 executing a program stored in the memory unit 52.
[0050] At least a part of the lift command value calculation unit 54, the roll moment command value calculation unit 56, the pitch moment command value calculation unit 58, the yaw moment command value calculation unit 60, the mode selection unit 62, the thrust command value calculation unit 64, the allocation command value calculation unit 66, the control surface control command value generation unit 68, the control surface control unit 70, the VTOL rotor command value generation unit 72, the VTOL motor control unit 74, the pitch control unit 76, the cruise rotor command value generation unit 78, the cruise motor control unit 80, and the pitch control unit 82 may be realized by an integrated circuit such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field-Programmable Gate Array).
[0051] At least a portion of the lift command value calculation unit 54, the roll moment command value calculation unit 56, the pitch moment command value calculation unit 58, the yaw moment command value calculation unit 60, the mode selection unit 62, the thrust command value calculation unit 64, the allocation command value calculation unit 66, the control surface control command value generation unit 68, the control surface control unit 70, the VTOL rotor command value generation unit 72, the VTOL motor control unit 74, the pitch control unit 76, the cruise rotor command value generation unit 78, the cruise motor control unit 80, and the pitch control unit 82 may be realized by an electronic circuit including a discrete device.
[0052] The storage unit 52 is configured by a volatile memory (not shown) and a non-volatile memory (not shown), which are computer-readable storage media. The volatile memory is, for example, a random access memory (RAM). The non-volatile memory is, for example, a read-only memory (ROM), a flash memory, etc. Data, etc., are stored in the volatile memory. Programs, tables, maps, etc., are stored in the non-volatile memory. At least a part of the storage unit 52 may be provided in the above-mentioned processor, integrated circuit, etc.
[0053] The lift command value calculation unit 54 calculates a lift command value. The lift command value is determined, for example, according to the amount of operation of the operation input unit by the pilot. The operation input unit is, for example, a control stick, pedals, levers, etc. The amount of operation of the operation input unit and the lift command value do not need to correspond one-to-one. The lift command value for the amount of operation of the operation input unit may differ depending on the operation range of the operation input unit, the operation speed of the operation input unit, the altitude of the aircraft 16, etc. The altitude of the aircraft 16 is estimated, for example, based on the distance between the ground and the aircraft 16 detected by a ground range finder (not shown). The altitude of the aircraft 16 is estimated, for example, based on a signal received from a GNSS (Global Navigation Satellite System).
[0054] If the pilot does not input an operation to the operation input unit, the lift command value may be automatically determined and the aircraft may hover, regardless of the amount of operation of the operation input unit. Also, if the aircraft 10 is automatically piloted, the lift command value may be automatically determined according to a preset flight path, regardless of the amount of operation of the operation input unit.
[0055] The roll moment command value calculation unit 56 calculates a roll moment command value. The roll moment command value is determined according to the amount of operation of the operation input unit by the pilot. The amount of operation of the operation input unit and the roll moment command value do not need to correspond one-to-one. The roll moment command value corresponding to the amount of operation of the operation input unit may differ depending on the operation range of the operation input unit, the operation speed of the operation input unit, the altitude of the aircraft 16, etc. The angular velocity of the aircraft 16 is detected by, for example, a gyro sensor (not shown).
[0056] If the pilot does not input an operation to the operation input unit, the roll moment command value may be automatically determined and the aircraft may hover, regardless of the amount of operation of the operation input unit. Also, if the aircraft 10 is automatically piloted, the roll moment command value may be automatically determined according to a preset flight path, regardless of the amount of operation of the operation input unit.
[0057] The pitch moment command value calculation unit 58 calculates a pitch moment command value. The pitch moment command value is determined, for example, according to the amount of operation of the operation input unit by the pilot. The amount of operation of the operation input unit and the pitch moment command value do not necessarily correspond one-to-one. The pitch moment command value for the amount of operation of the operation input unit may differ depending on the operation range of the operation input unit, the operation speed of the operation input unit, the altitude of the aircraft 16, etc.
[0058] If the pilot does not input an operation to the operation input unit, the pitch moment command value may be automatically determined and the aircraft may hover, regardless of the amount of operation of the operation input unit. Also, if the aircraft 10 is automatically piloted, the pitch moment command value may be automatically determined in accordance with a preset flight path, regardless of the amount of operation of the operation input unit.
[0059] The yaw moment command value calculation unit 60 calculates a yaw moment command value. The yaw moment command value is determined, for example, according to the amount of operation of the operation input unit by the pilot. The amount of operation of the operation input unit and the yaw moment command value do not necessarily correspond one-to-one. The yaw moment command value corresponding to the amount of operation of the operation input unit may differ depending on the operation range of the operation input unit, the operation speed of the operation input unit, the altitude of the aircraft 16, etc.
[0060] If the pilot does not input an operation to the operation input unit, the yaw moment command value may be automatically determined and the aircraft may hover, regardless of the amount of operation of the operation input unit. Also, if the aircraft 10 is automatically piloted, the yaw moment command value may be automatically determined in accordance with a preset flight path, regardless of the amount of operation of the operation input unit.
[0061] The mode selection unit 62 selects the normal mode or the energy saving mode. The selection of the normal mode or the energy saving mode may be based on, for example, the operation of a switch (not shown) by the pilot. The selection of the normal mode or the energy saving mode may also be automatically selected based on, for example, the remaining amount of fuel.
[0062] When the normal mode is selected, for example, during cruising, the stopping rotation angle of the VTOL rotor 12 and the pitch of the blades 26 are controlled, thereby controlling the magnitude of the lift and moment acting on the airframe 16. When the energy saving mode is selected, for example, during cruising, the stopping rotation angle of the VTOL rotor 12 and the pitch of the blades 26 are controlled, thereby controlling the magnitude of the drag acting on the airframe 16 to be smaller than when the normal mode is selected. Note that even when the stopping rotation angle of the VTOL rotor 12 and the pitch of the blades 26 are controlled to control the magnitude of the lift and moment acting on the airframe 16, the lift and moment acting on the airframe 16 may be controlled by controlling the control surfaces of the front wings 18 and rear wings 20.
[0063] The thrust command value calculation unit 64 calculates a thrust command value. The thrust command value is determined, for example, according to the amount of operation of the operation input unit by the pilot. The amount of operation of the operation input unit and the thrust command value do not need to correspond one-to-one. The thrust command value corresponding to the amount of operation of the operation input unit may differ depending on the operation range of the operation input unit, the operation speed of the operation input unit, the altitude of the aircraft 16, etc. The airspeed of the aircraft 16 is detected, for example, by an airspeed sensor (not shown).
[0064] If the pilot does not input an operation to the operation input unit, the thrust command value may be determined automatically, and the aircraft 10 may fly at a constant speed. Also, if the aircraft 10 is automatically piloted, the thrust command value may be determined automatically according to a preset flight path, regardless of the amount of operation of the operation input unit.
[0065] The allocation command value calculation unit 66 calculates an allocation command value for each of the lift command value, roll moment command value, pitch moment command value, and yaw moment command value. The allocation command value indicates, among each command value, a command value allocated to the control surface control of the front wing 18 and rear wing 20, and a command value allocated to the control of the VTOL rotor 12. The allocation command value may be calculated according to the selected mode from the normal mode and the energy saving mode. The allocation is determined according to the magnitude of each command value. Current A command value may be calculated.
[0066] The control surface control command value generation unit 68 generates drive command values for the ailerons, elevators, and rudder based on the assigned command values allocated to the control surface control of the front wings 18 and rear wings 20. The control surface control unit 70 controls the drive mechanisms that drive the ailerons, elevators, and rudder based on the drive command values.
[0067] When the normal mode is selected by the mode selection unit 62, the VTOL rotor command value generation unit 72 generates a drive command value for the VTOL motor 30 based on the assigned command value assigned to the control of the VTOL rotor 12. The VTOL rotor command value generation unit 72 generates a drive command value for the blades 26 of the VTOL rotor 12 based on the assigned command value assigned to the control of the VTOL rotor 12.
[0068] When the energy saving mode is selected by the mode selection unit 62, the VTOL rotor command value generation unit 72 sets the stop rotation position of the VTOL motor 30 and the pitch of the blades 26 so that the drag generated in the VTOL rotor 12 is smaller than when the normal mode is selected. The VTOL rotor command value generation unit 72 generates a drive command value for the VTOL motor 30 and a drive command value for the pitch drive mechanism 34 based on the set stop rotation position of the VTOL motor 30 and the pitch of the blades 26. The VTOL rotor command value generation unit 72 may set the stop rotation position of the VTOL motor 30 and the pitch of the blades 26 so that the drag generated in the VTOL rotor 12 is minimized.
[0069] The VTOL motor control unit 74 controls the inverter 32 based on a drive command for the VTOL motor 30. The pitch control unit 76 controls the pitch drive mechanism 34 based on a drive command value for the blades 26 of the VTOL rotor 12.
[0070] The cruise rotor command value generation unit 78 generates a drive command value for the cruise motor 40 based on the thrust command value. The cruise rotor command value generation unit 78 generates a drive command value for the blades of the cruise rotor 14 based on the thrust command value. The cruise motor control unit 80 controls the inverter 42 based on the drive command for the cruise motor 40. The pitch control unit 82 controls the pitch drive mechanism 44 based on the drive command value for the blades of the cruise rotor 14.
[0071] In the above, the thrust command value calculated in thrust command value calculation unit 64 is directly input to cruise rotor command value generation unit 78. Cruise rotor command value generation unit 78 generates a drive command value for cruise motor 40 based on the thrust command value.
[0072] Alternatively, the thrust command value may be input to the allocated command value calculation unit 66, similar to the lift command value, roll moment command value, pitch moment command value, and yaw moment command value. In this case, the allocated command value calculation unit 66 calculates allocated command values for each of the lift command value, roll moment command value, pitch moment command value, yaw moment command value, and thrust command value. The cruise rotor command value generation unit 78 may generate a drive command value for the cruise motor 40 based on the command value allocated to the cruise rotor 14.
[0073] [Forces generated in VTOL rotors when rotation stops] As described above, in the aircraft 10 of this embodiment, the stopping rotation angle of the VTOL rotors 12 and the pitch of the blades 26 are controlled while the VTOL rotors 12 are stopped from rotating. This controls the magnitude of lift generated in each of the VTOL rotors 12. As a result, the magnitude of lift acting on the airframe 16 and the magnitude of the moment acting around the center of gravity G of the airframe 16 are controlled.
[0074] When a moment is applied around the center of gravity G of the airframe 16, the control device 48 makes the moment generated by the force in the outer rotor located farther from the center of gravity G greater than the moment generated by the force in the inner rotor located closer to the center of gravity G. If the force generated in the outer rotor and the force generated in the inner rotor are the same, the moment acting around the center of gravity G of the airframe 16 due to the force generated in the outer rotor is greater than the moment acting around the center of gravity G of the airframe 16 due to the force generated in the inner rotor. Therefore, the control device 48 can ensure the moment to be applied around the center of gravity G of the airframe 16 while suppressing the forces generated in the outer rotor and inner rotor.
[0075] When a roll moment is applied around the center of gravity G of the airframe 16, the control device 48 creates a difference between the sum of the lifts of the four VTOL rotors 12 arranged to the left of the center of gravity G and the sum of the lifts of the four VTOL rotors 12 arranged to the right of the center of gravity G. In this case, the control device 48 makes the magnitude of the roll moment applied around the center of gravity G of the airframe 16 by the lift generated in the outer rotors greater than the magnitude of the roll moment applied around the center of gravity G of the airframe 16 by the lift generated in the inner rotors. In this case, the control device 48 may make the sum of the magnitudes of the lifts generated in the outer rotors greater than the sum of the magnitudes of the lifts generated in the inner rotors.
[0076] When a pitch moment is applied around the center of gravity G of the airframe 16, the control device 48 creates a difference between the sum of the lifts of the four VTOL rotors 12 arranged forward with respect to the center of gravity G and the sum of the lifts of the four VTOL rotors 12 arranged aft with respect to the center of gravity G. In this case, the control device 48 makes the magnitude of the pitch moment applied around the center of gravity G of the airframe 16 by the lift generated in the outer rotors greater than the magnitude of the pitch moment applied around the center of gravity G of the airframe 16 by the lift generated in the inner rotors. In this case, the control device 48 may make the sum of the magnitudes of the lifts generated in the outer rotors greater than the sum of the magnitudes of the lifts generated in the inner rotors.
[0077] When a yaw moment is applied around the center of gravity G of the airframe 16, the control device 48 creates a difference between the sum of the drags on each of the four VTOL rotors 12 arranged to the left of the center of gravity G and the sum of the drags on each of the four VTOL rotors 12 arranged to the right of the center of gravity G. In this case, the control device 48 makes the magnitude of the yaw moment applied around the center of gravity G of the airframe 16 due to the drag generated in the outer rotors greater than the magnitude of the yaw moment applied around the center of gravity G of the airframe 16 due to the drag generated in the inner rotors. In this case, the control device 48 may make the sum of the magnitudes of the lift generated in the outer rotors greater than the sum of the magnitudes of the lift generated in the inner rotors.
[0078] [VTOL rotor stop rotation angle control and blade pitch control] When the VTOL rotors 12 are stopped from rotating, the lift and drag generated in each of the VTOL rotors 12 are controlled by the stopping rotation position of the VTOL rotors 12 and the pitch of the blades 26.
[0079] When changing the lift and drag generated in each of the VTOL rotors 12 toward the command values, the control device 48 controls the pitch of the blades 26 to change the lift and drag, and then controls the stopping rotation position of the VTOL rotors 12 to change the lift and drag.
[0080] The stopped rotation position of the VTOL rotor 12 is maintained by the inverter 32 controlling the VTOL motor 30 to output a balancing torque to the VTOL motor 30 against the external force. When the stopped rotation position of the VTOL rotor 12 is changed, the balance between the external force and the torque of the VTOL motor 30 must be released. Compared to releasing the balance between the external force and the torque of the VTOL motor 30, the response speed of changing the pitch of the blades 26 is faster. This improves the response speed of changes in lift and drag generated in each of the VTOL rotors 12.
[0081] [Action and effect] In the aircraft 10 of this embodiment, when the airframe 16 has airspeed, lift and drag can be generated in the VTOL rotor 12 even when the VTOL rotor 12 is in a stopped rotation state.
[0082] Furthermore, in the aircraft 10 of this embodiment, the control device 48 controls the stop rotation angle of the VTOL rotors 12 and the pitch of the blades 26, and controls the force generated in each of the VTOL rotors 12 when the VTOL rotors 12 are in a state where the rotors are stopped from rotating, thereby applying a force to the airframe 16. As a result, even when the VTOL rotors 12 are in a state where the rotors are stopped from rotating, a force can be applied to the airframe 16 by the force generated in each of the VTOL rotors 12.
[0083] Furthermore, in the aircraft 10 of this embodiment, when a moment is generated around the center of gravity G of the airframe 16, the control device 48 makes the moment acting around the center of gravity G of the airframe 16 due to the force generated in the outer rotor larger than the moment acting around the center of gravity G of the airframe 16 due to the force generated in the inner rotor. This allows the control device 48 to ensure the moment acting around the center of gravity G of the airframe 16 while suppressing the forces generated in the outer rotor and inner rotor.
[0084] Furthermore, in the aircraft 10 of this embodiment, the control device 48 changes the lift and drag by controlling the stop rotation position of the VTOL rotors 12, after changing the lift and drag by controlling the pitch of the blades 26. This allows the control device 48 to improve response speed when changing the lift and drag generated in each of the VTOL rotors 12.
[0085] Furthermore, in the aircraft 10 of this embodiment, when an energy saving mode that prioritizes reducing drag acting on the airframe 16 is selected, the control device 48 controls the stop rotation angle of each of the VTOL rotors 12 and the pitch of each of the blades 26 to reduce the drag generated in each of the VTOL rotors 12 compared to when another mode is selected. This allows the aircraft 10 to reduce energy consumption.
[0086] [Variations] The VTOL rotor 12 of the aircraft 10 of the first embodiment rotates to generate lift that moves the airframe 16 upward. A tilt rotor that can change the orientation of the rotor relative to the airframe 16 may be used instead of the VTOL rotor 12. When the orientation of the tilt rotor relative to the airframe 16 is at a predetermined angle, the tilt rotor rotates to generate lift that moves the airframe 16 upward.
[0087] The VTOL rotors 12 of the aircraft 10 of the first embodiment are arranged in a plurality of (four in the first embodiment) VTOL rotors 12 in the fore-and-aft direction of the airframe 16. Alternatively, the VTOL rotors 12 of the aircraft 10 may be arranged in a plurality of VTOL rotors 12 in the left-and-right direction of the airframe 16. Furthermore, the VTOL rotors 12 of the aircraft 10 may be arranged in a plurality of VTOL rotors 12 in the up-and-down direction of the airframe 16.
[0088] In the first embodiment, the VTOL rotor 12 is connected to the VTOL motor 30. Alternatively, a gearbox may be provided between the VTOL motor 30 and the VTOL rotor 12. The gearbox is a transmission that changes the speed of the rotation of the VTOL motor 30 and transmits it to the VTOL rotor 12. Similarly, a gearbox may be provided between the cruise motor 40 and the cruise rotor 14.
[0089] [Inventions Obtained from the Embodiments] The invention that can be understood from the above embodiment will be described below.
[0090] A control device (48) for an aircraft (10) having a plurality of rotors (12) each having one or more blades (26) and rotating about a rotating shaft (24) to generate lift, and one or more fixed wings (18, 20) that generate lift when the airframe (16) has airspeed, the control device controls the pitch of each of the blades and the stop rotation angle of each of the rotors when lift is generated at the fixed wings, thereby controlling the force generated in each of the rotors when the rotors are stopped, thereby causing a force to be applied to the airframe by the force generated in each of the rotors even when the rotors are stopped.
[0091] In the control device for an aircraft described above, the aircraft has one or more inner rotors (12FLb, 12RLb, 12FRb, 12RRb) that are the rotors and one or more outer rotors (12FLa, 12RLa, 12FRa, 12RRa) that are the rotors, the distance from the center of gravity (G) of the airframe to the inner rotors is shorter than the distance from the center of gravity to the outer rotors, and when generating a moment around the center of gravity of the airframe, the control device may make the moment that is caused to act on the airframe by a force generated in the outer rotor larger than the moment that is caused to act on the airframe by a force generated in the inner rotor. This allows the control device to reduce the force generated in the rotor relative to the magnitude of the desired moment.
[0092] In the control device for an aircraft described above, the aircraft may have a front wing (18) that is the fixed wing and is located forward of the center of gravity of the airframe, a rear wing (20) that is the fixed wing and is located rearward of the center of gravity of the airframe, one or more first rotors (12FLa, 12FRa) that are the outer rotors and are located forward of the front wing, one or more second rotors (12FLb, 12FRb) that are the inner rotors and are located between the front wing and the center of gravity in the longitudinal direction of the airframe, one or more third rotors (12RLb, 12RRb) that are the inner rotors and are located between the center of gravity and the rear wing in the longitudinal direction of the airframe, and one or more fourth rotors (12RLa, 12RRa) that are the outer rotors and are located rearward of the rear wing. This allows the control device to reduce the force generated in the rotors relative to the magnitude of the required moment.
[0093] In the control device for an aircraft, when changing the force generated in each of the rotors, the control device may change the force generated in each of the rotors by controlling the stop rotation angle of each of the rotors after changing the force generated in each of the rotors by controlling the pitch of each of the blades, thereby enabling the control device to improve response speed when changing the force generated in each of the rotors.
[0094] In the control device for an aircraft, when an energy-saving mode that prioritizes reducing drag acting on the airframe is selected, the stop rotation angle of each of the rotors and the pitch of each of the blades may be controlled to reduce drag generated in each of the rotors compared to when another mode is selected, thereby enabling the aircraft to reduce energy consumption.
[0095] The present invention is not limited to the above disclosure, and various configurations can be adopted without departing from the gist of the present invention. [Explanation of symbols]
[0096] 10...Aircraft 12...VTOL rotor (rotor) 12FLa...Rotor (outer rotor, first rotor) 12FLb...Rotor (inner rotor, second rotor) 12RLa...Rotor (outer rotor, 4th rotor) 12RLb...Rotor (inner rotor, third rotor) 12FRa...Rotor (outer rotor, first rotor) 12FRb...Rotor (inner rotor, second rotor) 12RRa...Rotor (outer rotor, 4th rotor) 12RRb...Rotor (inner rotor, third rotor) 18...Forward wing (fixed wing) 20...Back wing (fixed wing) 24...Rotating shaft 26...Blade 48...Control device
Claims
1. a plurality of rotors, each having one or more blades, rotating about a rotating shaft to generate lift; one or more fixed wings that generate lift when the aircraft has airspeed; An aircraft control device having: An aircraft control device that performs pitch control to control the pitch of each of the blades and stop rotation angle control to control each of the rotors to stop at a predetermined rotation angle when lift is generated in the fixed wing, thereby generating a moment around the center of gravity of the aircraft due to the lift and drag generated in each of the blades.
2. A plurality of rotors, each having one or more blades and rotating around a rotating shaft to generate lift; one or more fixed wings that generate lift when the aircraft has airspeed; An aircraft control device having: An aircraft control device that, during cruising, performs pitch control to control the pitch of each of the blades and stop rotation angle control to control each of the rotors to stop at a predetermined rotation angle, thereby generating a moment around the center of gravity of the aircraft due to the lift and drag generated in each of the blades.
3. 3. The aircraft control device according to claim 1 or 2, The aircraft one or more inner rotors, one or more outer rotors, and a distance from the center of gravity of the airframe to the inner rotor is shorter than a distance from the center of gravity to the outer rotor; an aircraft control device that, when generating a moment around the center of gravity of the aircraft, makes the moment acting on the aircraft due to a force generated in the outer rotor greater than the moment acting on the aircraft due to a force generated in the inner rotor.
4. 4. The aircraft control system according to claim 3, The aircraft a front wing that is the fixed wing and is provided forward of the center of gravity of the airframe; a rear wing that is the fixed wing and is provided rearward of the center of gravity of the airframe; one or more first rotors that are the outer rotors and are provided forward of the front wing; one or more second rotors that are the inner rotors and are provided between the front wing and the center of gravity in the longitudinal direction of the airframe; one or more third rotors that are the inner rotors and are provided between the center of gravity and the rear wing in the longitudinal direction of the airframe; one or more fourth rotors that are the outer rotors and are provided rearward of the rear wing; An aircraft control device comprising:
5. 3. The aircraft control device according to claim 1 or 2, a control device for an aircraft, wherein, when changing the force generated in each of the rotors, the force generated in each of the rotors is changed by controlling the pitch of each of the blades, and then the force generated in each of the rotors is changed by controlling the stop rotation angle of each of the rotors.
6. 3. The aircraft control device according to claim 1 or 2, an aircraft control device that, when an energy-saving mode that prioritizes reducing drag acting on the airframe is selected, controls the stopping rotation angle of each of the rotors and the pitch of each of the blades to reduce drag generated in each of the rotors compared to when another mode is selected.
Citation Information
Patent Citations
Aircraft
JP2022019033A
Compound multi-copter aircraft
US20190127056A1
Vertical take-off and landing (VTOL) aircraft with cruise rotor positioning control for minimum drag
US20200079501A1
Procedure for maneuvering a hybrid aerodyne of VTOL or stol
US20210011493A1
Aircraft
WO2022130500A1