Variable configuration biomimetic cross-media unmanned vehicle based on canted folding wings and method

Abstract

This invention provides a variable-layout biomimetic cross-medium unmanned aerial vehicle and method based on a folding wing, comprising a blended hull, a foldable wing, a Y-shaped tail, and a biomimetic buoyancy system. The foldable wing is installed at the intersection of the forward main structure and the aft main structure of the blended hull. The foldable wing is capable of being folded in half, has an adjustable dihedral angle, and can be rotated. The variable-layout biomimetic cross-medium unmanned aerial vehicle and method based on a folding wing provided by this invention features a wing mechanism design that allows the wing to fold and conform to the fuselage shape in underwater navigation, forming another underwater vehicle shape. This design also maintains the lightweight, flexible, and structurally strong nature of the wing mechanism. This invention enables simultaneous underwater, surface, and air navigation capabilities, and can switch layouts multiple times across water and air media.

Description

Technical Field

[0001] This invention belongs to the field of aircraft design technology, specifically relating to a variable-layout biomimetic cross-medium unmanned aerial vehicle and method based on an obliquely folding wing. Background Technology

[0002] Transmedium-water unmanned aerial vehicles (UAVs) represent a crucial development direction for future maritime warfare, naval power, maritime rescue, resource exploration, and environmental monitoring. Currently, the hull designs for transmedium-water entry and exit lack stability and reliability. Approximately 45% of transmedium-water UAVs use splashdown entry. Since the density difference between water and air is approximately 800 times, and the dynamic viscosity coefficient of water is about 60 times that of air, the abrupt change in medium when the UAV splashes into the water generates a significant impact force, placing high demands on the structural strength and impact resistance of sensitive components. About 40% of stable and reliable UAVs use water-surface gliding for takeoff and landing. This method places lower demands on the impact resistance of the aircraft structure, but because the UAV moves at the interface between air and water phases, factors such as air-water coupling and water surface viscosity result in a longer transition time and require a longer takeoff distance. In addition, in order to take into account the different aerodynamic and hydrodynamic shapes of unmanned aerial vehicles (UAVs) in submerged and flight states, maintain the structural reliability and stability requirements of the deployed wings during flight, and reduce the overall wetted area of ​​the UAV in water during underwater navigation, the design of the variable wing mechanism is usually quite complex. Therefore, this type of variable wing mechanism occupies more weight, resulting in a significant decrease in the UAV's payload and fuel consumption. Summary of the Invention

[0003] To address the shortcomings of existing technologies, this invention provides a variable-layout biomimetic cross-medium unmanned aerial vehicle and method based on obliquely folding wings, which can effectively solve the above-mentioned problems.

[0004] This invention provides a variable-layout biomimetic cross-medium unmanned vehicle based on a folding oblique wing, including a blended hull, a folding wing, a Y-shaped tail, and a biomimetic buoyancy system.

[0005] The integrated hull includes a forward main structure, integrated hydrofoils, and a rear main structure; the forward and rear main structures are connected aft to aft; the integrated hydrofoils are arranged opposite each other on the left and right sides of the forward main structure; the Y-shaped tail fin is installed at the stern of the rear main structure; and the biomimetic buoyancy system is installed inside the integrated hull.

[0006] The foldable wing is installed at the intersection of the forward main structure of the integrated hull and the aft main structure of the integrated hull. The foldable wing is a wing that can be folded in half, has an adjustable dihedral angle, and can be rotated and folded. When the foldable wing is fully folded, it is placed obliquely and attached to the lower surface of the aft main structure of the integrated hull.

[0007] Preferably, the bottom of the integrated hull front main structure is provided with a hull structure and a wave-damping groove structure.

[0008] Preferably, the foldable wings are arranged symmetrically on the left and right, and each side of the foldable wing includes a wing root turntable, a front wing section, a rear wing section, an upper dihedral pivot, a limiting rail, a wing half-folding pivot, a wing half-folding power source, and a folding wing support.

[0009] The foldable wing is mounted to the root of the blended hydrofoil via the foldable wing bracket; the front wing and the rear wing are connected by the wing split-folding pivot.

[0010] The wing root turntable is installed in the folding wing bracket. The rotating shaft of the wing root turntable is embedded in the limiting rail. The limiting rail is used to limit the sliding trajectory of the wing root turntable, so that the front wing section and the rear wing section rotate around the dihedral rotating shaft as the rotation center. The dihedral rotating shaft is installed below the wing root turntable for adjusting the dihedral angle of the front wing section and the rear wing section.

[0011] The end of the front wing is connected to the wing root turntable; the wing split folding power source is installed on the wing root turntable, and its output end is connected to the wing split folding pivot, which is used to realize the rotation of the rear wing around the wing split folding pivot, thereby realizing the wing unfolding or folding.

[0012] Preferably, the Y-shaped tail fin includes a V-shaped tail fin, a water rudder, a variable-pitch coaxial twin propeller, and a power plant fairing;

[0013] The V-shaped tail fin includes a first tail fin and a second tail fin that are symmetrically arranged on both sides; the variable pitch coaxial twin propeller is arranged between the first tail fin and the second tail fin and on the upper surface of the main structure of the aft section of the integrated hull; the power unit fairing is installed on the outside of the variable pitch coaxial twin propeller.

[0014] Preferably, the biomimetic buoyancy system includes a first front airbag, a second front airbag, a first rear airbag, a second rear airbag, a first connecting air tube, a second connecting air tube, a third connecting air tube, a fourth connecting air tube, a high-pressure tank, a pump, and a support.

[0015] The first and second front airbags are symmetrically arranged vertically on both sides of the front main structure of the integrated hull; the first and second rear airbags are symmetrically located at the bottom of the rear main structure of the integrated hull.

[0016] The first front airbag and the second rear airbag are connected by the first connecting air tube; the second front airbag and the second rear airbag are connected by the second connecting air tube.

[0017] One end of the high-pressure tank is connected to the first front airbag via a third connecting air pipe; the other end of the high-pressure tank is connected to the second front airbag via a fourth connecting air pipe.

[0018] The pump is connected and energized to the high-pressure tank via the bracket; the pump is connected to the outside of the main structure of the front section of the fusion hull, and can pump out external water and control the water-to-air ratio in the airbag; the first and second connecting air pipes are convex upwards, and the end structure of the foldable wing is installed in the space below them.

[0019] This invention provides a method for a variable-layout biomimetic cross-medium unmanned aerial vehicle based on a folding oblique wing, wherein the working process of the integrated hull, foldable wing, Y-shaped tail, and biomimetic buoyancy system is as follows:

[0020] 1) Integrated hull design:

[0021] The integrated hull structure of the cross-medium unmanned aircraft is based on the wave-damping structure of a seaplane hull. Integrated hydrofoils are embedded on both sides of the hull. After the wings are deployed, the rear section of the foldable wings forms a step and bilge structure unique to seaplane hulls due to the lateral rotation of the turntable at the wing root. This reduces the water encroachment volume of the rear fuselage. At the same time, the integrated hydrofoils at the lower section interact with the water to generate lift, raising the wing root above the water surface. This improves the airflow environment around the hull and wings, thereby shortening the takeoff distance of the aircraft. During underwater navigation, the integrated hydrofoils also adjust the aircraft's attitude.

[0022] 2) Foldable wings:

[0023] Wing folding process: First fold: The front and rear wing sections fold in half around the wing folding pivot and powered by the wing folding power source, causing the rear wing to fold under the front wing section; then the dihedral angle of the wing is increased by the dihedral pivot. Second fold: The wing is folded to the lower rear fuselage surface using the oblique pivot of the wing root turntable as the rotation center. This unfolding and folding process minimizes the impact of changes in wing position and shape on the aircraft's water taxiing takeoff and landing.

[0024] Wing deployment process: First fold: The front and rear sections of the wing, which have been folded in half, are unfolded diagonally, with the upper dihedral angle of the folded wing unfolding diagonally; Second fold: The dihedral angle of the wing is reduced and the rear section of the wing is flipped. The gradually flipped rear section of the wing will initially generate greater drag, but during this process, when the two airfoils form an angle greater than 90° with the front section of the wing, the camber formed by the two airfoils can generate enough lift to allow the aircraft to quickly leave the water and take off.

[0025] 3) Y-shaped tail fin:

[0026] A water rudder is added to the tail fin. The water rudder can adjust the course of the vehicle both underwater and on the surface. In the air, it acts as a ventral fin of the aircraft. At the same time, the small hydrofoils at the tips of the water rudder generate lift during high-speed gliding on the water surface during the takeoff phase, supporting the main structure of the integrated stern section of the hull and reducing gliding drag. In order to meet the operational reliability and propulsion efficiency of the unmanned vehicle's power system in both water and air environments, a variable pitch coaxial twin propeller is used as the propulsion device.

[0027] Rear fuselage sloping lower side surface design:

[0028] The lower side surface of the rear fuselage of the cross-medium non-aerial vehicle corresponds to the shape of the upper surface of the front wing. The wings are folded and placed at an angle to fit the fuselage. The fit is based on the shape of the upper surface of the front wing and completely corresponds to the shape of the lower surface of the rear fuselage. This ensures that the wings, which are folded in half along the span, have sufficient chord length, i.e. sufficient wing size, and can fit completely into the main structure of the blended hull after folding without creating any gaps that waste space.

[0029] 4) Bionic buoyancy system:

[0030] The cross-medium unmanned aerial vehicle (UAV) uses an onboard pump to fill the airbags with compressed air from a high-pressure tank and expel water from the fuselage, enabling the UAV to float. The pump draws air from the airbags into the high-pressure tank, and water enters the first front airbag, second front airbag, first rear airbag, and second rear airbag, enabling the UAV to submerge. When surfacing or submerging, the tail fin's control surfaces and the blended hydrofoils on both sides of the fuselage are used to adjust the UAV's attitude.

[0031] The technical solution adopted in this invention is as follows:

[0032] The biomimetic cross-medium unmanned aerial vehicle and method based on a slanted folding wing provided by this invention have the following advantages:

[0033] This invention provides a variable-layout biomimetic cross-medium unmanned aerial vehicle and method based on a folding, obliquely mounted wing. The wing mechanism design allows the wing to fold and conform to the fuselage shape during underwater navigation, forming another underwater vehicle shape. This design also maintains the lightweight, flexible, and structurally strong nature of the wing mechanism. This invention enables simultaneous underwater, surface, and air navigation capabilities, and allows for multiple layout changes to traverse water and air media. Attached Figure Description

[0034] Figure 1 Two-dimensional views of a variable-layout biomimetic cross-medium unmanned aerial vehicle based on an obliquely folding wing, provided for the present invention;

[0035] Figure 2 This is the main drawing of the integrated head unit of the present invention;

[0036] Figure 3 This is a bottom view of the integrated nose section of the present invention;

[0037] Figure 4 This is a side view of the fused machine head of the present invention;

[0038] Figure 5 This is the main drawing of the variable wing of the present invention;

[0039] Figure 6 This is the main drawing of the variable wing of the present invention;

[0040] Figure 7 This is a magnified detail of the variable wing of the present invention;

[0041] Figure 8 This is a diagram showing the left deformable wing of the present invention in its folded intermediate state.

[0042] Figure 9 This is the main drawing of the Y-shaped tail fin and power unit of the present invention;

[0043] Figure 10 This is a side view of the Y-shaped tail fin of the present invention;

[0044] Figure 11 This is a rear view of the Y-shaped tail fin of the present invention;

[0045] Figure 12 This is the main diagram of the buoyancy system of the present invention;

[0046] Figure 13 This is a front view of the buoyancy system of the present invention;

[0047] Figure 14 This is a top view of the buoyancy system of the present invention;

[0048] Figure 15 This is a diagram illustrating the folding process of the variable wing of the present invention;

[0049] Figure 16 This is a comparison of the main images showing the wings of the present invention unfolding and folding.

[0050] Figure 17 This is a comparative top view of the wing of the present invention from unfolded to folded;

[0051] Figure 18 This is a side view comparing the wings of the present invention from unfolded to folded.

[0052] Figure 19 This is a detailed illustration of the power unit of the present invention;

[0053] Figure 20 This is a cross-sectional view showing the wing folding mechanism of the present invention;

[0054] Figure 21 This is a comparison image of the left deformable wing of the present invention before and after being folded in half along the spanwise axis;

[0055] Figure 22 This is a cross-sectional view of the folding wing of the present invention when it is attached to the rear fuselage underside;

[0056] Figure 23 This is a front view of the Y-shaped tail fin and a diagram showing the bottom outline of the stern hull of the present invention;

[0057] Figure 24 This is a rear view of the entire aircraft and a detailed view of the aircraft with the wings folded into the rear fuselage belly.

[0058] Figure 25 This is a diagram showing the installation location of the buoyancy system of the present invention;

[0059] Figure 26 This is a flowchart of the control process for the wing tilting system of the present invention. Detailed Implementation

[0060] To make the technical problems solved, the technical solutions, and the beneficial effects of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the invention.

[0061] This invention proposes a variable-layout biomimetic cross-medium unmanned aerial vehicle based on an obliquely folding wing mechanism, which has the following advantages:

[0062] (1) This invention possesses simultaneous underwater, surface, and air navigation capabilities, and can switch configurations to traverse water and air media multiple times. The vehicle, equipped with corresponding sensors, specialized equipment, or weapons, performs specific tasks underwater, on the surface, or in the air. For military applications, upon receiving an attack mission, it can use flight mode to rapidly approach the target from the air. Once the unmanned vehicle reaches the target area, it can flexibly choose between air, surface, or underwater attack methods; alternatively, it can first use underwater navigation mode and then ambush the target from the water. During the approach to the target, if an emergency occurs, the vehicle can quickly enter another medium for tactical evasion. If the mission is adjusted, it can also remain afloat on the water.

[0063] (2) The present invention provides a variable-layout biomimetic cross-medium unmanned vehicle and method based on a folding oblique wing, comprising a blended hull, a foldable wing, a Y-shaped tail, a power unit, and a biomimetic buoyancy system. The design of the variable-wing mechanism allows the wing to fold and conform to the fuselage shape during underwater navigation, forming another underwater vehicle shape. Furthermore, this design maintains the lightweight, flexible, and structurally strong nature of the variable-wing mechanism.

[0064] (3) This design integrates the characteristics of both water and air unmanned systems, enabling special tasks based on two different media to be completed by a single vehicle, thereby improving the efficiency and success rate of the mission. In contrast, traditional submarine-launched cross-media unmanned vehicles still require additional carriers for underwater navigation, launch, and recovery, which is very inconvenient.

[0065] Specifically, the present invention provides a variable layout biomimetic cross-medium unmanned vehicle based on a folding wing, including a blended hull, a folding wing, a Y-shaped tail, and a biomimetic buoyancy system;

[0066] The integrated hull includes an integrated forward main structure, integrated hydrofoils, and an integrated aft main structure; the integrated forward and aft main structures are connected forward and backward; the bottom of the integrated forward main structure is provided with a hull structure and a wave-damping channel structure. The integrated hydrofoils are arranged opposite each other on the left and right sides of the integrated forward main structure; the Y-shaped tail fin is installed at the stern of the integrated aft main structure; the biomimetic buoyancy system is installed inside the integrated hull.

[0067] The foldable wing is installed at the intersection of the forward main structure of the integrated hull and the aft main structure of the integrated hull. The foldable wing is a wing that can be folded in half, has an adjustable dihedral angle, and can be rotated and folded. When the foldable wing is fully folded, it is placed obliquely and attached to the lower surface of the aft main structure of the integrated hull.

[0068] The foldable wings are symmetrically arranged on both sides. Each side of the foldable wing includes a wing root turntable, a front wing section, a rear wing section, an upper dihedral pivot, a limiting rail, a wing-half folding pivot, a wing-half folding power source, and a folding wing support.

[0069] The Y-shaped tail fin includes a V-shaped tail fin, a water rudder, a variable-pitch coaxial twin propeller, and a power plant fairing; the V-shaped tail fin includes a first tail fin and a second tail fin that are symmetrically arranged on both sides; the variable-pitch coaxial twin propeller is disposed between the first tail fin and the second tail fin and on the upper surface of the main structure of the aft section of the integrated hull; the power plant fairing is mounted on the outside of the variable-pitch coaxial twin propeller.

[0070] The biomimetic buoyancy system includes a first front airbag, a second front airbag, a first rear airbag, a second rear airbag, a first connecting air tube, a second connecting air tube, a third connecting air tube, a fourth connecting air tube, a high-pressure tank, a pump, and a support frame.

[0071] The first and second front airbags are symmetrically arranged vertically on both sides of the front main structure of the integrated hull; the first and second rear airbags are symmetrically located at the bottom of the rear main structure of the integrated hull.

[0072] The first front airbag and the second rear airbag are connected by the first connecting air tube; the second front airbag and the second rear airbag are connected by the second connecting air tube.

[0073] One end of the high-pressure tank is connected to the first front airbag via a third connecting air pipe; the other end of the high-pressure tank is connected to the second front airbag via a fourth connecting air pipe.

[0074] The pump is connected and energized to the high-pressure tank via the bracket; the pump is connected to the outside of the main structure of the front section of the fusion hull, and can pump out external water and control the water-to-air ratio in the airbag; the first and second connecting air pipes are convex upwards, and the end structure of the foldable wing is installed in the space below them.

[0075] This invention provides a method for a variable-layout biomimetic cross-medium unmanned aerial vehicle based on a folding oblique wing. The working process of the integrated hull, foldable wing, Y-shaped tail, and biomimetic buoyancy system is as follows:

[0076] 1) Integrated hull design:

[0077] The integrated hull structure of the cross-medium unmanned aircraft is based on the wave-damping structure of a seaplane hull. Integrated hydrofoils are embedded on both sides of the hull. After the wings are deployed, the rear section of the foldable wings forms a step and bilge structure unique to seaplane hulls due to the lateral rotation of the turntable at the wing root. This reduces the water encroachment volume of the rear fuselage. At the same time, the integrated hydrofoils at the lower section interact with the water to generate lift, raising the wing root above the water surface. This improves the airflow environment around the hull and wings, thereby shortening the takeoff distance of the aircraft. During underwater navigation, the integrated hydrofoils also adjust the aircraft's attitude.

[0078] 2) Foldable wings:

[0079] Wing folding process: First fold: The front and rear wing sections fold in half around the wing folding pivot and powered by the wing folding power source, causing the rear wing to fold under the front wing section; then the dihedral angle of the wing is increased by the dihedral pivot. Second fold: The wing is folded to the lower rear fuselage surface using the oblique pivot of the wing root turntable as the rotation center. This folding and unfolding process minimizes the impact of changes in wing position and shape on the aircraft's water taxiing takeoff and landing.

[0080] Wing deployment process: First fold: The front and rear sections of the wing, which have been folded in half, are unfolded diagonally, with the upper dihedral angle of the folded wing unfolding diagonally; Second fold: The dihedral angle of the wing is reduced and the rear section of the wing is flipped. The gradually flipped rear section of the wing will initially generate greater drag, but during this process, when the two airfoils form an angle greater than 90° with the front section of the wing, the camber formed by the two airfoils can generate enough lift to allow the aircraft to quickly leave the water and take off.

[0081] 3) Y-shaped tail fin:

[0082] Water rudders are added to the tail fin. The water rudders adjust the course of the vehicle both underwater and on the water surface, and act as ventral fins of the aircraft in the air. At the same time, the small hydrofoils at the tips of the water rudders generate lift during high-speed gliding on the water surface during the takeoff phase, supporting the main structure of the integrated stern section of the hull and reducing gliding drag. In order to meet the operational reliability and propulsion efficiency of the unmanned vehicle's power system in both water and air environments, variable pitch coaxial twin propellers are used as the propulsion device.

[0083] Tail wing lower surface design:

[0084] The lower side surface of the rear fuselage of the cross-medium non-aerial vehicle corresponds to the shape of the upper surface of the front wing. The wings are folded and placed at an angle to fit the fuselage. The fit is based on the shape of the upper surface of the front wing and completely corresponds to the shape of the lower surface of the rear fuselage. This ensures that the wings, which are folded in half along the span, have sufficient chord length, i.e. sufficient wing size, and can fit completely into the main structure of the blended hull after folding without creating any gaps that waste space.

[0085] 4) Bionic buoyancy system:

[0086] The cross-medium unmanned aerial vehicle (UAV) uses an onboard pump to fill the airbags with compressed air from a high-pressure tank and expel water from the fuselage, enabling the UAV to float. The pump draws air from the airbags into the high-pressure tank, and water enters the first front airbag, second front airbag, first rear airbag, and second rear airbag, enabling the UAV to submerge. When surfacing or submerging, the tail fin's control surfaces and the blended hydrofoils on both sides of the fuselage are used to adjust the UAV's attitude.

[0087] The present invention will now be described in detail with reference to the accompanying drawings:

[0088] like Figure 1 As shown, the design of this cross-medium unmanned aerial vehicle includes a blended hull, foldable wings, a Y-shaped tail and power plant, and a biomimetic buoyancy system.

[0089] like Figures 2-4 As shown, the forward section of the integrated hull includes a hull structure 1, a wave-damping groove structure 2, a first integrated hydrofoil 3, a second integrated hydrofoil 7, and a main structure of the forward section of the integrated hull 5.

[0090] The bottom of the integrated hull forward main structure 5 achieves water takeoff functionality through the hull structure 1, wave-damping groove structure 2, first integrated hydrofoil 3, and second integrated hydrofoil 7. The first integrated hydrofoil 3 and the second integrated hydrofoil 7 are symmetrically arranged. A first wing root turntable 4 and a second wing root turntable 6 (also described below as foldable wings) are mounted at the roots of the first integrated hydrofoil 3 and the second integrated hydrofoil 7. The cross-section of the integrated hull forward main structure 5 is connected to the integrated hull rear main structure 26 (also described below as a Y-shaped tail and power unit; this distinction is for illustrative purposes only).

[0091] like Figures 5-8 As shown, the foldable wing includes a first wing root turntable 4, a second wing root turntable 6, a first front wing section 13, a first rear wing section 14, a second front wing section 8, a second rear wing section 9, a first dihedral pivot 11, a second dihedral pivot 10, a limiting rail 12, a first wing half-folding pivot 15, a second wing half-folding pivot 18, a first folding wing support 16, a second folding wing support 17, a first wing half-folding power source 19, and a second wing half-folding power source 20.

[0092] The foldable wing is mounted on the positions of the first integrated hydrofoil 3 and the second integrated hydrofoil 7 via a first folding wing bracket 16 and a second folding wing bracket 17 (corresponding to the front section of the integrated hull described above). The first wing root turntable 4, the second wing root turntable 6, the first dihedral pivot 11, the second dihedral pivot 10, the first wing half-folding power source 19, and the second wing half-folding power source 20 are each mounted on the upper part of the first folding wing bracket 16 and the second folding wing bracket 17, collectively enabling wing folding and unfolding. The first dihedral pivot 11 and the second dihedral pivot 10 can adjust the dihedral angle of the wing; the first wing root turntable 4 and the second wing root turntable 6 can fold or unfold the wing; and the first wing half-folding pivot 15, the second wing half-folding pivot 18, the first wing half-folding power source 19, and the second wing half-folding power source 20 can fold each side of the wing in half. The first wing half-folding power source 19 and the second wing half-folding power source 20 are respectively installed on the first wing root turntable 4 and the second wing root turntable 6. The limiting track 12 is limited by the interlocking sliding of the cylindrical rotating shafts of the first wing root turntable 4 and the second wing root turntable 6. The sliding trajectory is centered on the first dihedral rotating shaft 11 and the second dihedral rotating shaft 10, and the contact position can satisfy the rotation of the entire wing section driven by the first wing root turntable 4 and the second wing root turntable 6 themselves.

[0093] like Figures 9-11 As shown, the Y-shaped tail fin and power plant include a first tail fin 21, a second tail fin 24, a water rudder 22, a variable pitch coaxial twin propeller 23, a power plant fairing 25, a first rear fuselage lower side surface 27, a second rear fuselage lower side surface 28, and a blended hull rear main structure 26.

[0094] The Y-shaped tail fin consists of a V-shaped tail fin composed of a first tail fin 21 and a second tail fin 24, and a water rudder 22. The variable-pitch coaxial twin propeller 23 is mounted on the upper part of the blended hull rear section main structure 26, and a power unit fairing 25 is installed on its exterior. The cross-section of the blended hull rear section main structure 26 is connected to the blended hull forward section main structure 5.

[0095] like Figures 12-14 As shown, the biomimetic buoyancy system includes a first front airbag 30, a second front airbag 29, a first rear airbag 36, a second rear airbag 35, a first connecting air pipe 34, a second connecting air pipe 33, a third connecting air pipe 38, a fourth connecting air pipe 37, a high-pressure tank 31, a pump 32, and a support 39.

[0096] The biomimetic buoyancy system is equipped with four airbags: a first front airbag 30, a second front airbag 29, a first rear airbag 36, and a second rear airbag 35. Two airbags are arranged in each group, one in the front main structure 5 and the other in the rear main structure 26 of the integrated hull. The four airbags are connected front to rear by a first connecting air pipe 34, a second connecting air pipe 33, a third connecting air pipe 38, and a fourth connecting air pipe 37, ultimately connecting to a pressure tank 31 and a pump 32. The pressure tank 31 and the pump 32 are connected and conductive by a bracket 39. The pump 32 is connected to the outside of the front main structure 5 of the integrated hull, enabling it to pump and release external water and control the water-to-air ratio in the airbags. The first connecting air pipe 34 and the second connecting air pipe 33 are upwardly convex, and the space below them houses the wing root turntable 14, the wing root turntable 26, and the limiting track 12.

[0097] The biomimetic cross-medium unmanned aerial vehicle based on a folding oblique wing provided by this invention mainly includes a blended hull, a foldable wing, a Y-shaped tail, and a biomimetic buoyancy system. The design and operational characteristics of each part are as follows:

[0098] The operational effects of the integrated hull design:

[0099] This integrated hull structure for a cross-medium, non-submersible aircraft is based on the wave-damping structure 2 of a seaplane hull. First integrated hydrofoils 3 and second integrated hydrofoils 7 are embedded on both sides of the hull. After the wings are deployed, the rear section of the variable-wing mechanism forms a step-like and bilge-like structure unique to seaplanes due to the lateral rotation of the first wing root turntable 4 and the second wing root turntable 6. This reduces the water-soaked volume of the rear fuselage. Simultaneously, the lower sections of the first and second integrated hydrofoils 3 and 7 generate lift through the water, raising the wing roots above the water surface. This improves the airflow environment around the hull and wings, thereby shortening the takeoff distance. During underwater navigation, the first and second integrated hydrofoils 3 and 7 can also adjust the aircraft's attitude.

[0100] The steps for achieving the deformation of the foldable wing are as follows:

[0101] like Figures 15-18 As shown, taking the wing folding process as an example, the first folding is achieved by using the first wing folding pivot 15 and the second wing folding pivot 18 as power sources for the first wing folding power source 19 and the second wing folding power source 20, respectively. The dihedral angle of the wings is then increased by the first dihedral pivot 11 and the second dihedral pivot 10, respectively. The second folding is achieved by using the oblique pivots of the first wing root turntable 4 and the second wing root turntable 6 as rotation centers to fold the wings to the lower oblique surfaces 27 and 28 of the first and second rear fuselage sections, respectively. This design minimizes the impact of wing position and shape changes on the aircraft's water-based takeoff and landing processes.

[0102] Taking the wing deployment process as an example, the first oblique deployment of the wing, which is already half-folded, can maintain the roll stability of the aircraft. The second deployment reduces the dihedral angle of the wing and flips the other half of the wing—the first rear section 14 and the second rear section 9. The gradually flipped other half of the wing will initially generate greater drag, but during the process, when it forms an angle greater than 90° with the main wing—the first front section 13 and the second front section 8, the camber formed by the two airfoils can generate enough lift to enable the aircraft to quickly take off from the water.

[0103] The Y-shaped tail fin and power unit (variable pitch coaxial twin propeller) operate as follows:

[0104] This design incorporates water rudders 22 on the tail fin while maintaining control of the aircraft's flight surfaces. The water rudders 22 can adjust the vehicle's course both underwater and on the surface, and in the air, they function as ventral fins. Furthermore, the small hydrofoils at the tips of the water rudders 22 generate lift during high-speed gliding on the water surface during takeoff, supporting the integrated aft main structure 26 and reducing drag. To ensure the reliability and propulsion efficiency of the unmanned aerial vehicle's propulsion system in both water and air environments, this design uses variable-pitch coaxial twin propellers 23 as the propulsion device. Figure 19 As shown, the propeller of this propulsion device can change the pitch, tilt angle, leading edge angle, and longitudinal tilt angle of the blades.

[0105] Design effect of the lower rear fuselage surface:

[0106] like Figures 20-24 As shown, the lower oblique surface 27 of the first rear fuselage and the lower oblique surface 28 of the second rear fuselage of this transmedium-less aircraft are designed to correspond to the upper surface shapes of the first forward wing 13 and the second forward wing 8, respectively. After folding, the wings are obliquely positioned and fitted to the fuselage, with the fitting point based on the upper surface shape of the forward wing, perfectly corresponding to the lower surface shape of the rear fuselage. This ensures that the wings, folded in half along the spanwise direction, have sufficient chord length, i.e., sufficient wing size, and after folding again, can completely fit into the integrated rear main structure 26 without creating any wasted space.

[0107] How the biomimetic buoyancy system works:

[0108] like Figure 25As shown, this cross-medium unmanned aerial vehicle (UAV) borrows the surfacing and diving mechanisms of fish. It uses a pump 32 to fill the airbags with compressed air from a high-pressure tank 31 and expel water from the fuselage, enabling surfacing. The pump 32 draws air from the airbags into the high-pressure tank 31, and water enters the first front airbag 30, second front airbag 29, first rear airbag 36, and second rear airbag 35, enabling diving. During surfacing or diving, the control surfaces of the first tail fin 21 and second tail fin 24, along with the first blended hydrofoils 3 and second blended hydrofoils 7 on both sides of the fuselage, adjust the UAV's attitude.

[0109] The biomimetic cross-medium unmanned aerial vehicle and method based on a slanted folding wing provided by this invention have the following advantages:

[0110] 1. The integrated hull structure of this cross-medium unmanned aerial vehicle (UAV), combining wave-damping channels and hydrofoils, is based on the wave-damping channel design of a seaplane hull. A hydrofoil structure is embedded and integrated into each side of the hull. After the wings are deployed, the rear section of the variable-wing mechanism, due to the lateral rotation at the wing root, forms a stepped and bilge structure unique to seaplane hulls. This reduces the water ingress volume of the rear fuselage. Simultaneously, the lower hydrofoils generate lift through the water, raising the wing root above the water surface, improving the airflow environment around the hull and wings, thereby shortening the takeoff distance. During underwater navigation, the integrated hydrofoils can also adjust the vehicle's attitude.

[0111] 2. This cross-medium unmanned aerial vehicle (UAV) employs a two-stage folding wing device based on an obliquely oriented pivot. Taking the wing folding process as an example, the wing is first folded in half along its spanwise axis, increasing the dihedral angle; the second fold is performed with the wing root centered on a vertically oriented oblique pivot, folding towards the rear of the vehicle to the main body. This design minimizes the impact of wing position and shape changes on the vehicle's water-based takeoff and landing. Taking the wing deployment process as an example, the first oblique deployment of the half-folded wing maintains the vehicle's roll stability. The second deployment reduces the dihedral angle and flips the other half of the wing. Initially, the gradually flipping wing generates significant drag, but the camber formed by the two airfoils at an angle greater than 90° to the main wing generates sufficient lift to allow the vehicle to quickly leave the water and take off.

[0112] 3. The rear fuselage shape of this cross-medium unmanned aerial vehicle is designed to correspond to the upper surface shape of its wing. When folded, the wing is angled and fitted to the fuselage, with the fitting point based on the upper surface shape of the wing, perfectly corresponding to the lower surface shape of the rear fuselage. This ensures that the wing, folded in half along the spanwise direction, has sufficient chord length, i.e., sufficient wing size, and can completely integrate into the rear fuselage after folding without creating any wasted space.

[0113] 4. The Y-shaped tail of this cross-medium unmanned aerial vehicle consists of a V-shaped tail and a water rudder. This design incorporates water rudders on the tail while also providing control over flight surfaces in the air. These water rudders can adjust the vehicle's heading both underwater and on the water surface, and in the air, they function as ventral fins. Additionally, the small hydrofoils at the tips of the water rudders can lift the tail of the vehicle during high-speed gliding on the water surface during takeoff, reducing drag.

[0114] 5. The propulsion system of this cross-medium unmanned aerial vehicle (UAV) is designed to operate in both water and air, utilizing lithium batteries as its sole energy source. Because water is approximately 800 times denser than air, the underwater propulsion system requires higher torque and lower rotational speed compared to air-based thrusters, necessitating different blade shapes. Frequent switching between water and air environments can cause severe corrosion to the gearbox structure, and there is also the issue of dead weight when the two propulsion systems are idle. Therefore, to ensure the reliability and propulsion efficiency of the UAV's propulsion system in both water and air environments, this design employs a variable-pitch coaxial dual-propeller propulsion system. The propeller of this system can adjust its pitch, tilt angle, leading edge angle, and longitudinal tilt angle.

[0115] 6. This cross-medium unmanned aerial vehicle (UAV) employs a pump, pressure tank, and airbag system, drawing inspiration from the surfacing and diving mechanisms of fish. When diving, the onboard air pump inflates the airbag with compressed air from the high-pressure tank, expelling water from the fuselage and allowing the UAV to surface. Conversely, the air pump draws air from the airbag into the high-pressure tank, allowing water to enter the fuselage and enabling the entire vehicle to dive. During surfacing and diving, the tail fin's control surfaces and the blended hydrofoils on both sides of the fuselage adjust the UAV's attitude.

[0116] 7. This cross-medium unmanned aerial vehicle can be equipped with an airspeed measurement unit, a pitch measurement unit, and an acceleration measurement unit to perform real-time attitude calculations. The data is processed by the flight controller's dual-precision computing unit and continuously outputs PWM signals, which enable the servo motor to control the tilt system of the semi-folded wing to dynamically compensate for the angle of attack. It also synchronizes with the electronic speed controller to adjust the output power of the power source, completing the closed loop of the PID control chain. This allows the aircraft to dynamically adjust the angle of attack at different airspeeds and different flight stages, achieving coordination between the flight trajectory angle, attitude angle, and the rear wing angle of attack, so as to achieve high angle of attack short takeoff and reduce the water surface taxiing distance.

[0117] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method of a variable configuration biomimetic cross-media unmanned vehicle based on a canted folded wing, characterized in that, The variable-layout biomimetic cross-medium unmanned vehicle based on obliquely folding wings includes a blended hull, foldable wings, Y-shaped tail, and a biomimetic buoyancy system. The integrated hull includes a forward main structure, integrated hydrofoils, and a rear main structure; the forward and rear main structures are connected aft to aft; the integrated hydrofoils are arranged opposite each other on the left and right sides of the forward main structure; the Y-shaped tail fin is installed at the stern of the rear main structure; and the biomimetic buoyancy system is installed inside the integrated hull. The foldable wing is installed at the intersection of the main front structure of the integrated hull and the main rear structure of the integrated hull. The foldable wing is a wing that can be folded in half, has an adjustable dihedral angle, and can be rotated and folded. After the foldable wing is fully folded, it is placed obliquely and attached to the lower surface of the main rear structure of the integrated hull. The bottom of the integrated hull forward main structure is provided with a hull structure and a wave-damping groove structure. The foldable wing is symmetrically arranged on the left and right sides. Each side of the foldable wing includes a wing root turntable, a front wing section, a rear wing section, an upper dihedral pivot, a limiting rail, a wing half-folding pivot, a wing half-folding power source, and a folding wing support. The foldable wing is mounted to the root of the blended hydrofoil via the foldable wing bracket; the front wing and the rear wing are connected by the wing split-folding pivot. The wing root turntable is installed in the folding wing bracket. The rotating shaft of the wing root turntable is embedded in the limiting rail. The limiting rail is used to limit the sliding trajectory of the wing root turntable, so that the front wing section and the rear wing section rotate around the dihedral rotating shaft as the rotation center. The dihedral rotating shaft is installed below the wing root turntable for adjusting the dihedral angle of the front wing section and the rear wing section. The end of the front wing is connected to the wing root turntable; the wing split folding power source is installed on the wing root turntable, and its output end is connected to the wing split folding pivot, which is used to realize the rotation of the rear wing around the wing split folding pivot, thereby realizing the wing unfolding or folding. The working process of the integrated hull, foldable wings, Y-shaped tail, and biomimetic buoyancy system is as follows: 1) Composite hull: The integrated hull structure of the cross-medium unmanned aerial vehicle is based on the wave-damping groove structure of a seaplane hull. Integrated hydrofoils are embedded on both sides of the hull. After the wings are deployed, the rear section of the foldable wings forms a step and bilge structure unique to seaplane hulls due to the lateral rotation of the turntable at the wing root. This reduces the water encroachment volume of the rear section of the vehicle. At the same time, the integrated hydrofoils at the lower section interact with the water to generate lift, lifting the wing root off the water surface. During underwater navigation, the integrated hydrofoils also adjust the vehicle's attitude. 2) Foldable wings: Wing folding process: First fold: The front and rear wing sections fold in half around the wing folding pivot and powered by the wing folding power source, causing the rear wing to fold under the front wing section; then the dihedral angle of the wing is increased by the dihedral pivot. Second fold: The wing is folded to the lower rear fuselage surface using the oblique pivot of the wing root turntable as the rotation center. This unfolding and folding process minimizes the impact of changes in wing position and shape on the aircraft's water taxiing takeoff and landing. Wing deployment process: First fold: The front and rear sections of the wing, which have been folded in half, are unfolded diagonally, and the upper dihedral of the folded wing is unfolded diagonally; Second fold: The dihedral of the wing is reduced and the rear section of the wing is flipped. 3) Y-shaped tail fin: A water rudder is added to the tail fin. The water rudder can adjust the course of the vehicle both underwater and on the surface. In the air, it acts as a ventral fin of the aircraft. At the same time, the small hydrofoils at the tips of the water rudder generate lift during high-speed gliding on the water surface during the takeoff phase, supporting the main structure of the integrated stern section of the hull and reducing gliding drag. In order to meet the operational reliability and propulsion efficiency of the unmanned vehicle's power system in both water and air environments, a variable pitch coaxial twin propeller is used as the propulsion device. 4) Bionic buoyancy system: The cross-medium unmanned aerial vehicle (UAV) uses an onboard pump to fill the airbags with compressed air from a high-pressure tank and expel water from the fuselage, enabling the UAV to float. The pump draws air from the airbags into the high-pressure tank, and water enters the first front airbag, second front airbag, first rear airbag, and second rear airbag, enabling the UAV to submerge. When surfacing or submerging, the tail fin's control surfaces and the blended hydrofoils on both sides of the fuselage are used to adjust the UAV's attitude.

2. The method for a variable-layout biomimetic cross-medium unmanned aerial vehicle based on an obliquely folding wing according to claim 1, characterized in that, The rear fuselage of the cross-medium unmanned aerial vehicle is designed with the upper surface of the front wing corresponding to its shape. The wings are folded and placed at an angle to fit the fuselage. The fit is based on the shape of the upper surface of the front wing and corresponds to the shape of the lower surface of the rear fuselage. This ensures that the wings, which are folded in half along the span, have sufficient chord length, i.e., sufficient wing size, and can fit completely into the main structure of the aft section of the integrated ship after folding without creating any gaps that waste space.

3. The method for a variable-layout biomimetic cross-medium unmanned aerial vehicle based on an obliquely folding wing according to claim 1, characterized in that, The Y-shaped tail fin includes a V-shaped tail fin, a water rudder, a variable-pitch coaxial twin propeller, and a power plant fairing. The V-shaped tail fin includes a first tail fin and a second tail fin that are symmetrically arranged on both sides; the variable pitch coaxial twin propeller is arranged between the first tail fin and the second tail fin and on the upper surface of the main structure of the aft section of the integrated hull; the power unit fairing is installed on the outside of the variable pitch coaxial twin propeller.

4. The method of claim 1, wherein, The biomimetic buoyancy system includes a first front airbag, a second front airbag, a first rear airbag, a second rear airbag, a first connecting air tube, a second connecting air tube, a third connecting air tube, a fourth connecting air tube, a high-pressure tank, a pump, and a support frame. The first and second front airbags are symmetrically arranged vertically on both sides of the front main structure of the integrated hull; the first and second rear airbags are symmetrically located at the bottom of the rear main structure of the integrated hull. The first front airbag and the second rear airbag are connected by the first connecting air tube; the second front airbag and the second rear airbag are connected by the second connecting air tube. One end of the high-pressure tank is connected to the first front airbag via a third connecting air pipe; the other end of the high-pressure tank is connected to the second front airbag via a fourth connecting air pipe. The pump is connected and energized to the high-pressure tank via the bracket; the pump is connected to the outside of the main structure of the front section of the fusion hull, and can pump out external water and control the water-to-air ratio in the airbag; the first and second connecting air pipes are convex upwards, and the end structure of the foldable wing is installed in the space below them.

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