Tilt-rotor aircraft and control method thereof

Abstract

The invention discloses a tilt rotor aircraft and a control method thereof, and belongs to the technical field of rotorcrafts, the tilt rotor aircraft comprises a fuselage, wings are respectively arranged on two sides of the middle position of the fuselage, head rotor groups are respectively arranged on two sides of the head position of the fuselage, tail rotor groups are respectively arranged on two sides of the tail position of the fuselage, and the wings are provided with middle rotor groups. Comprising three control modes including a helicopter mode, a transition mode and a fixed wing mode, by designing a tilt rotor scheme with a high safety coefficient, the design difficulty and the structural complexity of the rotor aircraft in a flight control system are reduced, and then the stability and the safety of the rotor aircraft are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of rotorcraft, and in particular to a tiltrotor aircraft and a control method thereof. Background Art

[0002] Currently, tilt-rotor aircraft combine the characteristics of helicopters and fixed-wing aircraft. They have both rotors and wings. The rotors can switch between vertical and horizontal positions, making the tilt-rotor aircraft have the advantages of vertical take-off and landing of helicopters and the advantages of high-speed cruising of fixed-wing aircraft.

[0003] The relevant technology can refer to the existing tilt-rotor aircraft represented by the US V-22 Osprey, which has a pair of tilt-rotors. During takeoff, the rotors are parallel to the ground. After takeoff, the rotors tilt 90° to complete the mode switch from vertical takeoff to high-speed cruising.

[0004] With respect to the above-mentioned related technologies, the applicant has found that the complex aerodynamic characteristics and flight dynamic characteristics of the rotor tilt process pose great challenges to the flight control and transmission structure of the rotorcraft, increasing the risk of instability and loss of control of the rotorcraft. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present invention provides a tiltrotor aircraft and a control method thereof. By designing a tiltrotor solution with a high safety factor, the difficulty in designing a flight control system and the complexity of the structure of the rotorcraft are reduced, thereby improving the stability and safety of the rotorcraft.

[0006] The technical solution of the present invention to solve the above technical problems is as follows:

[0007] A tiltrotor aircraft comprises a fuselage, wings are respectively arranged on both sides of the middle position of the fuselage, head rotor groups are respectively arranged on both sides of the head position of the fuselage, tail rotor groups are respectively arranged on both sides of the tail position of the fuselage, and a middle rotor group is arranged on the wings.

[0008] Furthermore, the head rotor group includes at least two rotors, and the head rotor group is symmetrically distributed with respect to the fuselage.

[0009] Furthermore, the middle rotor group includes at least two rotors, and the middle rotor group is symmetrically distributed with respect to the fuselage.

[0010] Furthermore, the tail rotor group includes at least two rotors, and the tail rotor group is symmetrically distributed with respect to the fuselage.

[0011] Furthermore, the head rotor group, the middle rotor group and the tail rotor group can all achieve a tilt of 0° to 90°.

[0012] A tilt-rotor aircraft control method includes three control modes: helicopter mode, transition mode and fixed-wing mode.

[0013] Use helicopter mode before takeoff, with the rotors level with the ground and rotating at the same time, which provides lift for the aircraft to take off vertically or hover;

[0014] After takeoff, use the transition mode to increase the rotation speed of some rotors and reduce the rotation speed of others. Under the premise of ensuring the balance of the aircraft, some rotors will stop rotating. At this time, tilt the stopped rotors until they are vertical to the ground. Then open the stopped rotors and increase the rotation speed. At this time, the rotors provide the aircraft with forward traction and lift. At the same time, the wings generate upward lift. During the forward flight of the aircraft, reduce the rotation speed of the rotors that are horizontal to the ground until they stop rotating. At this time, the lift is completely provided by the wings.

[0015] After forward flight, use the fixed-wing mode to tilt the stalled rotor until it is vertical to the ground, then open the stalled rotor and increase the rotation speed to provide the aircraft with forward flight power and achieve a fixed cruising state.

[0016] Furthermore, in helicopter mode, the rotor is parallel to the ground, providing vertical lift for the aircraft, enabling vertical ascent and descent and hovering in the air.

[0017] Furthermore, in the transition mode, the rotor is tilted within an angle range of 0° to 90° with the ground, and the rotor provides a transition from vertical lift to forward flight thrust for the aircraft, thereby enabling the aircraft to fly forward in the horizontal direction.

[0018] Furthermore, in the transition mode, under the premise of ensuring the balance of the aircraft, the rotation speeds of any two sets of rotors are increased, and the rotation speed of any one set of rotors is reduced.

[0019] Furthermore, in fixed-wing mode, the rotor is perpendicular to the ground, the wing provides all the lift for the aircraft, and the rotor provides all the pulling force for the aircraft.

[0020] In summary, compared with the prior art, the above technical solution has the following beneficial effects:

[0021] (1) The present invention reduces the difficulty of designing a flight control system and the complexity of the structure of a rotorcraft by designing a tilt-rotor solution with a high safety factor, thereby improving the stability and safety of the rotorcraft;

[0022] (2) Compared with fixed-wing aircraft, tilt-rotor aircraft can take off and land vertically without taxiing on a specific airport runway. This means that when using tilt-rotor aircraft, there is no need to focus on the impact of the take-off environment. They can be used in both mountainous areas with harsh terrain conditions and densely populated urban areas.

[0023] (3) Compared with helicopters, tilt-rotor aircraft have faster speed, stronger cruising capability and longer endurance, which makes them more efficient. The excellent operating capability of tilt-rotor aircraft is favored by various countries and is widely used in monitoring and inspection, material delivery, disaster relief, logistics and transportation, power inspection, pesticide spraying and other fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the overall structure in an embodiment of the present invention.

[0025] Explanation of the accompanying drawings: 1. fuselage; 2. wing; 3. rotor one; 4. rotor two; 5. rotor three; 6. rotor four; 7. rotor five; 8. rotor six. DETAILED DESCRIPTION

[0026] The principles and features of the present invention are described below in conjunction with all the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0027] The embodiment of the invention discloses a tiltrotor aircraft and a control method thereof.

[0028] Reference Figure 1 A tilt-rotor aircraft comprises a fuselage 1, wings 2 are respectively arranged on both sides of the middle position of the fuselage 1, and head rotor groups are respectively arranged on both sides of the head position of the fuselage 1, the head rotor group comprises at least two rotors, and the head rotor group is symmetrically distributed with respect to the fuselage 1. In this embodiment, the head rotor group comprises rotor 1 3 and rotor 2 4, rotor 1 3 and rotor 2 4 are respectively symmetrically arranged on both sides of the head position of the fuselage 1, and rotor 1 3 and rotor 2 4 can achieve an angle of tilt of 0° to 90°. Rotor 1 3 and rotor 2 4 are connected to the fuselage 1 through short wings, and the short wings can also provide lift during flight.

[0029] The wing 2 is provided with a middle rotor group, which includes at least two rotors, and the middle rotor group is symmetrically distributed with respect to the fuselage 1. In this embodiment, the middle rotor group includes rotor three 5 and rotor four 6, which are symmetrically arranged on both sides of the middle position of the fuselage 1, and both rotor three 5 and rotor four 6 can achieve an angle tilt of 0° to 90°.

[0030] The tail rotor group is provided on both sides of the tail position of the fuselage 1, and the tail rotor group includes at least two rotors, and the tail rotor group is symmetrically distributed with respect to the fuselage 1. In this embodiment, the tail rotor group includes rotor 5 7 and rotor 6 8, and rotor 5 7 and rotor 6 8 are symmetrically arranged on both sides of the tail position of the fuselage 1, and rotor 5 7 and rotor 6 8 can achieve an angle of tilt of 0° to 90°. Rotor 5 7 and rotor 6 8 are connected to the fuselage 1 through short wings, and the short wings can also provide lift during flight.

[0031] The head rotor group, the middle rotor group and the tail rotor group, including rotor one 3, rotor two 4, rotor three 5, rotor four 6, rotor five 7 and rotor six 8 in this embodiment can all achieve a tilt of 0° to 90°.

[0032] A tiltrotor aircraft control method includes three control modes: a helicopter mode, a transition mode and a fixed-wing mode.

[0033] Before taking off, use the helicopter mode, the rotor is horizontal to the ground, and the rotor is rotated at the same time, which provides the aircraft with lift for vertical takeoff or hovering. In helicopter mode, the rotor is parallel to the ground, and the rotor provides vertical lift for the aircraft to achieve vertical takeoff and hovering in the air.

[0034] After takeoff, the transition mode is used to increase the rotation speed of some rotors and reduce the rotation speed of some rotors. Under the premise of ensuring the balance of the aircraft, until some rotors stop rotating, the stopped rotors are tilted until they are vertical to the ground, and then the stopped rotors are opened and the rotation speed is increased. At this time, the rotors provide the aircraft with forward traction and lift, and wing 2 generates upward lift. During the forward flight of the aircraft, the rotation speed of the rotors horizontal to the ground is reduced until it stops rotating. At this time, the lift is completely provided by wing 2. In the transition mode, the rotors are tilted within the angle range of 0° to 90° with the ground, and the rotors provide the aircraft with a transition from vertical lift to forward traction, so as to realize the forward flight of the aircraft in the horizontal direction. In the transition mode, under the premise of ensuring the balance of the aircraft, the rotation speed of any two sets of rotors is increased, and the rotation speed of any set of rotors is reduced.

[0035] The rotors 1 3 and 2 4 can be shut down and stopped, and the rotors 3 5, 4 6, 5 7 and 6 8 can be used to control the balance and provide lift in the transition mode, and then the rotors 1 3 and 2 4 can be turned on after they are tilted 90° to provide the aircraft with power to fly forward. The rotors 3 5 and 4 6 can also be shut down and stopped, and the rotors 1 3, 2 4, 5 7 and 6 8 can be used to control the balance and provide lift in the transition mode, and then the rotors 3 5 and 4 6 can be turned on after they are tilted 90° to provide the aircraft with power to fly forward. The rotors 5 7 and 6 8 can also be shut down and stopped, and the rotors 1 3, 2 4, 5 7 and 6 8 can be used to control the balance and provide lift in the transition mode, and then the rotors 5 7 and 6 8 can be turned on after they are tilted 90° to provide the aircraft with power to fly forward.

[0036] After forward flight, use the fixed-wing mode, tilt the stalled rotor until it is vertical to the ground, open the stalled rotor and increase the speed to provide the aircraft with forward flight power, and achieve the fixed cruising state of the aircraft. In the fixed-wing mode, the rotor is vertical to the ground, wing 2 provides all the lift for the aircraft, and the rotor provides all the pulling force for the aircraft.

[0037] The tilt-rotor aircraft is composed of a wing 2 (here, wing 2 is a fixed wing) and a rotor. The rotor can usually be tilted 0° to 90°, and then through three flight modes: helicopter mode, transition mode, and fixed-wing mode. Compared with fixed-wing aircraft, tilt-rotor aircraft can take off and land vertically without taxiing on a specific airport runway. This means that when using tilt-rotor aircraft, there is no need to focus on the impact of the take-off environment. It can be used in both mountainous areas with harsh terrain conditions and densely populated urban areas.

[0038] Compared with helicopters, tilt-rotor aircraft have faster speed, stronger cruising ability and longer endurance, which makes them more efficient. The excellent operating ability of tilt-rotor aircraft is favored by various countries and is widely used in monitoring and inspection, material delivery, disaster relief, logistics and transportation, power inspection, pesticide spraying and other fields.

[0039] The cruising speed of the V-22 Osprey is 509km / h, and its maximum speed can reach 650km / h, which is comparable to conventional turboprop fixed-wing aircraft, and its fuel range exceeds 1,850km. In helicopter mode, it can achieve vertical takeoff or hover in the air, with the rotor parallel to the ground, providing all the lift for the aircraft to take off or hover. After taking off to a certain height, it switches to transition mode, and the tilt-rotor tilts a certain angle to pull the aircraft forward. At this time, the lift is composed of wing 2 and the rotor. In fixed-wing mode, the rotor tilts 90°, at which time the lift is provided by wing 2, and the rotor only provides pulling force.

[0040] In transition mode, the lift of the aircraft is provided by the rotor and wing 2, which requires both thrust vector control of the rotor and air rudder control. The coordination of the three control modes of helicopter mode, transition mode and fixed-wing mode can reduce the control requirements for the aircraft, reduce the control difficulty of the aircraft when switching from helicopter mode to transition mode and from transition mode to fixed-wing mode, and improve the stability and safety of the aircraft during flight.

[0041] This embodiment arranges three groups of rotors, rotor 1 3 and rotor 2 4 in one group, rotor 3 5 and rotor 4 6 in one group, and rotor 5 7 and rotor 6 8 in one group. When the aircraft takes off vertically, the three groups of rotors work together. When transitioning to horizontal flight, any one group of rotors is closed first, and after the closed group of rotors is tilted 90°, the stopped rotors are restarted to generate a pulling force for the aircraft to fly forward. During the transition, the balance of the aircraft is controlled by any two groups of rotors and sufficient lift is provided. When wing 2 generates sufficient lift, the rotor group parallel to the ground is gradually closed, and after closing, the rotor group is tilted 90° until the rotor is vertical to the ground, completing the switch to fixed-wing flight and achieving level flight cruise. This solution decouples the flight control of the aircraft during the process of switching from helicopter mode to transition mode and from transition mode to fixed-wing mode, thereby improving the stability and safety of the aircraft.

[0042] The implementation principle of a tilt-rotor aircraft and a control method thereof according to an embodiment of the present invention is as follows:

[0043] In helicopter mode, the rotating surfaces of rotor one 3, rotor two 4, rotor three 5, rotor four 6, rotor five 7 and rotor six 8 are all horizontal with the ground, and the six rotors work simultaneously to provide the aircraft with the lift requirements for vertical takeoff or hovering.

[0044] After takeoff, the aircraft switches to transition mode, at which time the rotation speeds of rotor 1 3, rotor 2 4, rotor 5 7, and rotor 6 8 are increased to increase lift, while at the same time, the rotation speeds of rotor 3 5 and rotor 4 6 are reduced to balance the aircraft until rotor 3 5 and rotor 4 6 stop rotating. After rotor 3 5 and rotor 4 6 are closed, slowly tilt rotor 3 5 and rotor 4 6 90° until rotor 3 5 and rotor 4 6 are perpendicular to the ground, then open rotor 3 5 and rotor 4 6 and increase the rotation speed to keep the aircraft flying forward, at which time wing 2 generates upward lift. At the same time, the rotation speeds of rotor 1 3, rotor 2 4, rotor 5 7, and rotor 6 8 are gradually reduced until they are zero, at which time the lift is completely generated by wing 2, and rotor 3 5 and rotor 4 6 only provide pulling force for the aircraft to fly forward, completing the switching of transition mode.

[0045] In fixed-wing mode, rotor 1 3, rotor 2 4, rotor 5 7, rotor 6 8 are shut down, stopped and tilted 90° so that rotor 1 3, rotor 2 4, rotor 5 7, rotor 6 8 are perpendicular to the ground. When rotor 1 3, rotor 2 4, rotor 5 7, rotor 6 8 are turned on, they jointly provide forward flight traction for the aircraft, allowing the rotors to jointly participate in the fixed cruising state of the aircraft, completing the fixed-wing mode switch of the aircraft.

[0046] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A tilt-rotor aircraft, characterized in that: The invention comprises a fuselage (1), wings (2) are respectively arranged on both sides of the middle position of the fuselage (1), head rotor groups are respectively arranged on both sides of the head position of the fuselage (1), tail rotor groups are respectively arranged on both sides of the tail position of the fuselage (1), and the wings (2) are provided with a middle rotor group.

2. A tilt-rotor aircraft according to claim 1, characterized in that: The head rotor group comprises at least two rotors, and the head rotor group is symmetrically distributed with respect to the fuselage (1).

3. A tilt-rotor aircraft according to claim 1, characterized in that: The middle rotor group comprises at least two rotors, and the middle rotor group is symmetrically distributed with respect to the fuselage (1).

4. A tilt-rotor aircraft according to claim 1, characterized in that: The tail rotor assembly comprises at least two rotors, and the tail rotor assembly is symmetrically distributed with respect to the fuselage (1).

5. The tilt-rotor aircraft according to claim 1, characterized in that: The head rotor group, the middle rotor group and the tail rotor group can all achieve a tilt of 0° to 90°.

6. A tilt-rotor aircraft control method according to any one of claims 1 to 5, characterized in that: Including three control modes: helicopter mode, transition mode and fixed-wing mode. Use helicopter mode before takeoff, with the rotors level with the ground and rotating at the same time, which provides lift for the aircraft to take off vertically or hover; After takeoff, a transition mode is used to increase the rotation speed of some rotors and reduce the rotation speed of some rotors until some rotors stop rotating while ensuring the balance of the aircraft. At this time, the stopped rotors are tilted until they are vertical to the ground, and then the stopped rotors are opened and the rotation speed is increased. At this time, the rotors provide the aircraft with forward thrust and lift, and at the same time, the wing (2) generates upward lift. During the forward flight of the aircraft, the rotation speed of the rotors horizontal to the ground is reduced until they stop rotating, and at this time, the lift is completely provided by the wing (2); After forward flight, use the fixed-wing mode to tilt the stalled rotor until it is vertical to the ground, then open the stalled rotor and increase the rotation speed to provide the aircraft with forward flight power and achieve a fixed cruising state.

7. A tilt-rotor aircraft control method according to claim 6, characterized in that: In helicopter mode, the rotor is parallel to the ground, providing vertical lift for the aircraft, enabling vertical takeoff and landing and hovering in the air.

8. A tilt-rotor aircraft control method according to claim 6, characterized in that: In transition mode, the rotor tilts within an angle range of 0° to 90° to the ground, providing the aircraft with a transition from vertical lift to forward flight thrust, thereby enabling the aircraft to fly forward in the horizontal direction.

9. A tilt-rotor aircraft control method according to claim 6, characterized in that: In the transition mode, under the premise of ensuring the balance of the aircraft, the rotation speed of any two sets of rotors is increased, and the rotation speed of any one set of rotors is reduced.

10. A tilt-rotor aircraft control method according to claim 6, characterized in that: In the fixed-wing mode, the rotor is vertical to the ground, the wing (2) provides all the lift for the aircraft, and the rotor provides all the pulling force for the aircraft.

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