Aerodynamic layout of tiltable propeller unmanned aerial vehicle

Abstract

The invention provides a tiltable propeller unmanned aerial vehicle aerodynamic layout, and relates to the technical field of unmanned aerial vehicles, the tiltable propeller unmanned aerial vehicle aerodynamic layout comprises a fuselage, wings and a longitudinal beam, the longitudinal beam is installed in the middle of the wings, and the two ends of the longitudinal beam are each provided with a propeller with the adjustable inclination angle; the length of the longitudinal beam enables the distance from the edge of the wing to the center of the propeller to be larger than the radius of the propeller, and when the front-end propeller tilts forwards by 90 degrees and the rear-end propeller tilts backwards by 90 degrees and the rotating plane is a vertical plane, the front propeller and the rear propeller provide forward thrust for the aircraft on the premise that the rotating direction of the propellers is not changed. The four tilting propellers with power and the four wings are coupled to provide lifting force in the vertical direction and power in the advancing direction for the aircraft in the vertical take-off and landing and cruising states.

Description

Technical Field

[0001] This invention relates to the field of unmanned aerial vehicle (UAV) technology, specifically to an aerodynamic layout for a tiltable propeller-driven UAV. Background Technology

[0002] Generally, tiltrotor aircraft have low requirements for takeoff and landing sites, typically involving both vertical ascent and descent. The lift of the entire aircraft comes from the propellers in the power system. During level flight and cruise, thrust comes from all or part of the propellers rotating 90 degrees, while all or part of the lift comes from the wings. The American Osprey series and the R6000 from China's United Aircraft Corporation employ this structure where all propellers are tilted 90 degrees. However, the AE200 from Volvo Aircraft uses a larger number of propellers, allowing all lift during takeoff and landing to be provided by these propellers. During cruise, only a portion of the propellers need to tilt 90 degrees to provide thrust; the remaining propellers either continue rotating to provide lift along with the wings, or stop rotating, with lift provided solely by the wings. Another extreme case is that the aircraft uses two sets of propellers in a fixed direction: one set provides lift and the other provides thrust. The two have a clear division of labor and do not need to tilt. However, the setting of multiple propellers increases the basic weight of the aircraft, increases the cruise drag of the aircraft, and, most importantly, increases the complexity of the aircraft structure.

[0003] For tiltrotor aircraft, the ideal outcome is twofold: first, during takeoff and landing, the downdraft generated by the propeller should flow directly downwards undisturbed; second, the coupling energy between the airflow from the wing and propeller should effectively provide additional lift to the wing. However, current aircraft fall short in these aspects to some extent: For example, the main wing of the American Osprey series aircraft obstructs the airflow and creates significant interference when the propeller tilts downwards or tilts. The same applies to certain models of the Rainbow and the R6000. Furthermore, because the propellers are located at the wingtips and there is only one pair, the center of lift is on a horizontal line, and the stability and balance of the aircraft rely entirely on other mechanisms for counterbalance. The AE200, due to the lack of tilting capability in some of its propellers, is therefore an incomplete tiltrotor aircraft. Summary of the Invention

[0004] To achieve the above objectives, the present invention provides the following technical solution: an aerodynamic layout for a tiltable propeller-driven unmanned aerial vehicle (UAV), comprising a fuselage, wings, and a longitudinal beam. The longitudinal beam is installed in the middle region of each wing. Both ends of the longitudinal beam are equipped with propellers with adjustable tilt angles. The length of the longitudinal beam ensures that the distance from the wing edge to the center of the propeller is greater than the radius of the propeller. After the front propeller tilts forward by 90 degrees and the rear propeller tilts backward by 90 degrees, without changing the direction of propeller rotation, the resulting airflow helps to increase the lift of the wing. Furthermore, the rotation of the propellers causes the two propellers on one side of the wing to generate airflow in the same direction, resulting in the thrust being increased in opposite directions.

[0005] Preferably, a servo motor is arranged inside the longitudinal beam to drive the propeller for angle adjustment.

[0006] Preferably, during the tilting process, due to the longitudinal beam in the middle of the wing, only when the rotating surface of the propeller is close to vertical during the tilting process will a portion of the airflow from the propeller blow onto the wing, and this airflow will be oblique.

[0007] Preferably, the width of the longitudinal beam in the horizontal direction is 3 to 30 cm.

[0008] Preferably, a flight controller is arranged inside the fuselage, which independently controls the propeller and servo motor.

[0009] This invention provides an aerodynamic layout for a tiltable propeller-driven unmanned aerial vehicle (UAV). It offers the following advantages: This structure utilizes the coupling of four tilting, powered propellers and wings to provide lift and forward propulsion for the aircraft during vertical takeoff, landing, and cruise. This structure enables a simple and safe transition between vertical takeoff and landing and cruise because, during tilting, the airflow generated by the propellers is effectively converted into lift or thrust, while having a much smaller impact on the airflow to the wings compared to other tiltrotor structures. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the structure of the present invention in the vertical takeoff or landing state; Figure 2 This is a schematic diagram of the structure of the present invention in cruise mode; Figure 3 This is a schematic diagram of the structure of the present invention in the transition state.

[0011] Among them, 1. fuselage; 2. propeller; 3. wing; 4. longitudinal beam. Detailed Implementation

[0012] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0013] like Figure 1 As shown, this embodiment of the invention provides an aerodynamic layout for a tiltable propeller-driven unmanned aerial vehicle (UAV), including a fuselage 1, a wing 3, and a longitudinal beam 4. The longitudinal beam 4 is installed in the middle of the wing, and both ends of the longitudinal beam 4 are equipped with propellers 2 with adjustable tilt angles. The length of the longitudinal beam 4 is such that the distance from the edge of the wing 3 to the center of the propeller 2 is greater than the radius of the propeller. The width of the beam in the horizontal direction should be as narrow as possible to ensure that the beam has minimal interference with the propeller airflow when the propeller rotates horizontally. This ensures that the airflow generated by the propeller 2 during rotation is not significantly affected by the wing 3. When the propeller 2 tilts 90 degrees and the plane of rotation is vertical, a stable airflow field needs to be ensured. On the one hand, this increases the lift of the wing 3, and on the other hand, the airflow has minimal interference with the tail fin, thus achieving higher propulsion efficiency. The generated airflow helps increase the lift of the wing 3. Finally, the rotation of the propeller 2 enables the two propellers 2 on one side of the wing 3 to generate airflow in the same direction, resulting in thrust increasing in opposite directions.

[0014] The longitudinal beam 4 is equipped with a servo motor to drive the propeller 2 to adjust the angle. That is, the lift or thrust of the UAV is adjusted by driving the propeller 2 to adjust the angle.

[0015] During the tilting process, due to the longitudinal beam in the middle of the wing 3, only when the rotating surface of the propeller 2 is close to vertical during the tilting process will some of the airflow from the propeller 2 blow onto the wing 3, and it will be at an angle. Moreover, due to the tilting motion of the propeller 2, the effect is only manifested after the tilting angle is 45 degrees, at which point the main lift comes from the wing.

[0016] The fuselage 1 houses a flight controller that independently controls the propellers 2 and servo motors. During takeoff and landing, the center of lift can be changed within a plane by adjusting the rotational speed and lift of the four propellers 2. During cruise, the individual and precise adjustment of the rotational speed of the four propellers 2 is also beneficial for adjusting the flight attitude and heading, which is conducive to the transportation of cargo and personnel and the adjustment and change of flight attitude and route.

[0017] First, when the plane of rotation of propeller 2 is horizontal, the airflow generated by propeller 2 during rotation will not be disturbed by wing 3. This allows the downward airflow generated by propeller 2 to be converted into lift with maximum efficiency. Furthermore, if the airflow is disturbed by wing 3, the change in airflow direction can lead to unforeseen events and safety hazards, especially during takeoff and landing.

[0018] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An aerodynamic layout for a tiltable propeller-driven unmanned aerial vehicle (UAV), characterized in that: The system includes a fuselage, wings, and longitudinal beams. The longitudinal beams are installed in the middle of the wings, and each end of the longitudinal beam is equipped with an adjustable tilt angle propeller. The length of the longitudinal beams is such that the distance from the edge of the wing to the center of the propeller is greater than the radius of the propeller. When the front propeller tilts forward by 90 degrees and the rear propeller tilts backward by 90 degrees, and the plane of rotation is vertical, without changing the direction of propeller rotation, the generated airflow helps to increase the lift of the wing. On the other hand, the rotation of the propellers causes the two propellers on one side of the wing to generate airflow in the same direction, resulting in thrust increasing in opposite directions.

2. The aerodynamic layout of a tiltable propeller-driven unmanned aerial vehicle according to claim 1, characterized in that: The longitudinal beam contains a servo motor to drive the front and rear propellers to adjust their angles.

3. The aerodynamic layout of a tiltable propeller-driven unmanned aerial vehicle according to claim 1, characterized in that: During the tilting process, due to the longitudinal spars in the middle of the wing, only when the rotating surfaces of the front and rear propellers are close to vertical during the tilting process does a portion of the airflow from the propellers blow onto the wing, and even then, it is at an angle.

4. The aerodynamic layout of a tiltable propeller-driven unmanned aerial vehicle according to claim 1, characterized in that: The width of the longitudinal beam in the horizontal direction is 3~30cm.

5. The aerodynamic layout of a tiltable propeller-driven unmanned aerial vehicle according to claim 2, characterized in that: The fuselage houses a flight controller that independently controls the propeller and servo motors.

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