Vertical take-off and landing fixed-wing unmanned aerial vehicle and working method

Abstract

The invention relates to a vertical take-off and landing fixed-wing unmanned aerial vehicle and a working method, according to the tailstock type vertical take-off and landing fixed-wing unmanned aerial vehicle, high-aspect-ratio wings are arranged, the space size needed by storage and transportation of the unmanned aerial vehicle is effectively reduced, and the vertical take-off and landing fixed-wing unmanned aerial vehicle meets the storage and storage requirements of different carriers in the fields of sea, land, air and the like; meanwhile, a periodic variable pitch propeller is arranged, pitching and rolling control torque in the vertical state is provided through tilting of a propeller disc, a reliable control means is provided for the unmanned aerial vehicle during switching between the vertical state and the level flight state, and the unmanned aerial vehicle has high maneuverability in the vertical state; through coupling of inertia force and aerodynamic force, under the auxiliary action of the periodic variable pitch propellers, the wings are unfolded or folded through the inertia force, then the aerodynamic force is changed by controlling deflection of the control surfaces to finely control unfolding or folding of the wings, automatic folding and unfolding of the wings are completed on the premise that an additional folding and unfolding mechanism is not introduced, the structural weight is reduced, and the cost is reduced. And space is provided for performance improvement of the unmanned aerial vehicle.

Description

Technical Field

[0001] This invention relates to the field of unmanned aerial vehicle (UAV) overall design and control technology, specifically to a tail-mounted vertical take-off and landing (VTOL) fixed-wing UAV with foldable wings and a wing folding and unfolding control method. Background Technology

[0002] Small fixed-wing unmanned aerial vehicles (UAVs) have demonstrated great potential in emergency rescue, environmental monitoring, and other missions due to their excellent cruising efficiency, low manufacturing cost, and flexible deployment capabilities. However, the inherent range and endurance of small UAVs limit their operational radius. To overcome this limitation, transporting UAVs via carrier aircraft, ground vehicles, or ships to autonomously execute missions has become a reliable mission mode. This carrier-based transportation significantly expands the actual mission coverage of small UAVs. However, this specific loading requirement also places stringent demands on the physical dimensions of the UAVs, requiring them to be housed within the limited space of the carrier.

[0003] This compact size requirement directly contradicts the high aspect ratio aerodynamic layout needed for UAVs to improve endurance. Tail-seat vertical takeoff and landing fixed-wing UAVs, with their unique configuration, have successfully solved the takeoff and landing challenges in runway-less conditions and inherited the advantages of efficient cruise from fixed-wing platforms. However, to fully realize their aerodynamic potential, this configuration also requires a high aspect ratio wing, inevitably leading to a trade-off between storage and transport size and cruise performance.

[0004] Foldable wing technology is key to resolving the aforementioned contradictions. Existing transmission technologies each have their applicable scenarios but also significant limitations. Electric drive technology offers high control precision and flexible layout, but its core power components and associated reduction gears are often heavy and bulky, making them difficult to arrange within the space-constrained interior of the wing. Furthermore, it poses overload risks and protection challenges under high loads or harsh environments. Gear transmission mechanisms provide reliable transmission ratios and self-locking capabilities; however, gear meshing clearances can lead to transmission backlash, affecting the positioning accuracy and rigidity of the wing after deployment. They also suffer from wear, require lubrication, and need maintenance. While linkage mechanisms can achieve complex, customized motion trajectories, their multi-hinged design leads to accumulated clearances, significantly reducing end-effector positioning accuracy and overall rigidity. Moreover, the complex linkage layout is prone to interference with other internal wing structures. Crucially, these structures increase system complexity and overall weight. For small UAVs, controlling structural weight is a key factor affecting performance improvement. Therefore, achieving highly reliable and rigid autonomous wing folding and deployment while strictly controlling structural weight presents a significant challenge.

[0005] Among the existing publicly available technologies: Chinese invention patent application, publication number CN119734822A, entitled "A Tail-Seat Tailless Amphibious Aircraft with Foldable Wings and Design Method Thereof," discloses a method for optimizing the configuration and distribution of foldable wings, enabling UAVs to balance aerodynamic efficiency during aerial cruise and stability on water, and summarizes a system design method. However, the wing folding and unfolding method proposed in this method uses traditional servo motor direct control, resulting in an increase in the weight of the folding mechanism. Chinese invention patent application, publication number CN120646273A, entitled "A Foldable Wing with Separated Ribs," discloses a foldable wing structure that works in conjunction with two sets of four-bar linkages and separated ribs, enabling the aircraft to switch between quadcopter vertical takeoff and landing modes and fixed-wing efficient cruise modes. However, this design introduces additional structural weight and also presents issues with the reliability of complex mechanisms.

[0006] Therefore, there is a need in this field for an aircraft that can balance cruise efficiency, payload size, and structural weight, and there are also requirements for a highly reliable wing folding and deployment control method. This method is designed for tail-seat vertical takeoff and landing fixed-wing UAVs, introducing cyclic variable-pitch propeller-assisted control. Based on the fusion of inertial force and aerodynamics, it reduces weight and increases efficiency, achieving highly reliable and rigid autonomous folding and deployment of the wings without increasing structural weight. This allows the aircraft to simultaneously meet stringent vehicle storage and transportation size constraints and superior endurance performance. Summary of the Invention

[0007] In view of the above problems, the present invention provides a tail-seat vertical take-off and landing fixed-wing UAV and a folding and unfolding control method for the wings, which enables the aircraft to have excellent cruise efficiency and endurance without increasing structural weight, while achieving the effect of storage in a small vehicle. It has high space utilization, can take off and land vertically, does not introduce additional structural weight, is suitable for deployment in small space, and belongs to the field of unmanned aerial vehicles.

[0008] This invention provides a vertical takeoff and landing fixed-wing unmanned aerial vehicle, comprising: Main wing, fuselage 301 and vertical wing structure; The main wing includes a left wing and a right wing; The left wing includes an outer wing section 101 and a middle wing section 103-1; The right wing includes an outer wing section 2102 and a middle wing section 2103-2; The vertical wing structure includes tail fin one 201 and tail fin two 202; The mid-section wing 103-1 and mid-section wing 2 103-2 are respectively installed at the tail end of the fuselage 301; the mid-section wing 103-1 is also connected to the outer section wing 101, the mid-section wing 2 103-2 is also connected to the outer section wing 2 102, and the tail end of the fuselage 301 is also connected to the vertical wing 1 201 and the vertical wing 2 202; The first vertical stabilizer 201 is arranged vertically upward at the tail of the fuselage 301, and the second vertical stabilizer is arranged vertically downward at the tail of the fuselage 301, forming two vertical stabilizer surfaces to maintain lateral stability. The left wing and right wing respectively include power unit one and power unit two, which are used to provide vertical pull during the vertical take-off and landing phase and thrust during the level flight phase of the UAV. The power unit includes a periodic variable pitch propeller 501-1 and an electric motor 501-2 that is connected to the mid-section wing 103-1 and the periodic variable pitch propeller 501-1 respectively. The second power unit includes a periodic variable pitch propeller 502-1 and an electric motor 502-2 that is connected to the mid-section wing 103-2 and the periodic variable pitch propeller 502-1 respectively. The periodic variable pitch propeller one and periodic variable pitch propeller two achieve the tilting of the propeller disk through periodic pitch change, change the direction of the thrust, and provide sufficient pitch torque control capability, enabling the UAV to achieve autonomous vertical take-off and vertical landing.

[0009] Optionally, both the outer wing section 101 and the outer wing section 2 102 are foldable sections; Optionally, the outer wing section one further includes an aileron one 104, and the outer wing section two further includes an aileron two 105; The aileron 104 and aileron 2 105 provide pitch, roll and yaw control torques during the UAV's level flight phase, and provide aerodynamic force in conjunction with the slipstream generated by the rotation of the UAV's periodic variable pitch propeller during the vertical take-off and landing phase.

[0010] Optionally, the periodic variable pitch propeller 501-1 and motor 502-2 are located on the inner section of the wing 1, near the outer section of the wing 1, at the junction of the inner and outer sections of the wing 1; the periodic variable pitch propeller 502-1 and motor 502-2 are located on the inner section of the wing 2, near the outer section of the wing 2, at the junction of the inner and outer sections of the wing 2; the periodic variable pitch propeller 1 and motor 1 are symmetrically arranged with respect to the fuselage plane with respect to the periodic variable pitch propeller 2 and motor 2.

[0011] Optionally, it also includes locking mechanism one, locking mechanism two, rotating mechanism one and rotating mechanism two, to ensure that the mid-section wing one and mid-section wing two of the UAV can remain in a fixed position after being deployed; The corresponding rotating pair formed by the outer wing section 1 and the middle wing section 1 through the rotating mechanism 1 can rotate freely without an active control device.

[0012] Optionally, the locking mechanism includes a fixing ear piece 1001, a positioning hole 1002, a pin 1003, and an ear piece groove. The fixed lug 1001 is connected to the upper surface of the middle section wing 1. The positioning hole 1002 is provided on the fixed lug 1001 at one end near the outer section wing 1. The pin 1003 is provided in the lug groove 1 on the outer section wing 1 for connecting the positioning hole 1002. The lug groove 1 is provided on the upper wing surface of the outer section wing 1 on the side near the middle section wing 1 for connecting the lug groove 1. The shape of the lug groove 1 is consistent with the shape of the lug groove 1. The second locking mechanism includes a second fixing ear piece, a second positioning hole, a second pin, and a second ear piece groove; The second fixed lug is connected to the lower surface of the second middle section wing. The second positioning hole is located on the second fixed lug near the end of the second outer section wing. The second pin is located in the lug groove on the second outer section wing and is used to connect the second positioning hole.

[0013] Optionally, the upper surface of the pin 1003 is an inclined plane, wherein the lower side of the inclined plane of the pin 1003 faces the middle section of the wing and the higher side faces the outer section of the wing. The lower surface of the second pin is an inclined plane, wherein the lower side of the inclined plane of the second pin faces the middle section of the second wing, and the higher side faces the outer section of the second wing.

[0014] Optionally, the rotating mechanism includes a fixed ring 901, a rotating ring 902, and a rotating shaft 903; The fixed ring 901 is connected to the middle section wing 1, the rotating ring 902 is fixedly connected to the outer section wing 1, and the rotating shaft 903 is connected to the fixed ring 901 and the rotating ring 1 respectively. The two ends of the rotating shaft 903 are limited by the limiting boss 1 to prevent the outer section wing 1 from displacing along the axial direction. Optionally, the second rotating mechanism includes a second fixed ring, a second rotating ring, and a second rotating shaft; The fixed ring 2 is connected to the middle section wing 2, the rotating ring 2 is fixedly connected to the outer section wing 2, and the rotating shaft 2 is connected to the fixed ring 2 and the rotating ring 2 respectively. The two ends of the rotating shaft 2 are limited by the limiting boss 2 to prevent the outer section wing 2 from displacing along the axial direction.

[0015] Optionally, the tail fin 201 is equipped with an electromagnet 1101, and the lower surface of the outer wing is provided with a permanent magnet 1102. When the left wing is folded, when the outer wing is close to the wingtip of the vertical tail, the electromagnet 1101 is energized to attract the permanent magnet 1102 on the outer wing, thereby locking the folded state. The tail fin 202 is equipped with an electromagnet 2, and the upper surface of the outer wing 2 is arranged with a permanent magnet 2. When the right wing is folded, when the outer wing 2 is close to the wingtip of the vertical tail 2, the electromagnet 2 is energized and attracts the permanent magnet 2 on the outer wing 2, thereby locking the folded state.

[0016] Another object of the present invention is to provide a method for operating a vertical take-off and landing fixed-wing unmanned aerial vehicle, comprising: When the UAV takes off vertically with its wings in the unfolded state, pins 1003 and 2 receive control signals. Pin 1003 protrudes from the first plane of the lug slot of the outer wing 101, and pin 2 protrudes from the second plane of the lug slot of the outer wing 102. The outer wing 101 and the middle wing 103-1 unfold based on the first rotating mechanism and the periodic variable pitch propeller 501-1. The outer wing 102 and the middle wing 103-2 unfold based on the second rotating mechanism and the periodic variable pitch propeller 502-1. The fixed lug 1001 inserts pin 1 into the positioning hole 1002 along the inclined plane of pin 1003, and the fixed lug 2 inserts pin 2 into the positioning hole 2 along the inclined plane of pin 2. When the cyclic variable pitch propeller 1 501-1 and the cyclic variable pitch propeller 2 502-1 tilt in the same direction, they provide pitch control torque for the UAV. When the cyclic variable pitch propeller 1 501-1 and the cyclic variable pitch propeller 2 502-1 of the UAV tilt in opposite directions, they provide the UAV with roll control torque. When the thrust provided by the UAV's cyclic variable pitch propeller 1 501-1 and cyclic variable pitch propeller 2 502-1 are different, a yaw control torque is provided for the UAV. When the UAV is in flight and the wings are in the deployed state, pins 1003 and 2 receive control folding signals and retract. Pin 1 retracts into the wing interior below the plane of the lug slot 1 of the outer wing section 1, and pin 2 retracts into the wing interior below the plane of the lug slot 2 of the outer wing section 2. The outer wing section 1 and the middle wing section 1 fold based on the rotation mechanism 1 and the periodic variable pitch propeller 1, and are fixed by electromagnet 1 and permanent magnet 1. The outer wing section 2 and the middle wing section 2 fold based on the rotation mechanism 2 and the periodic variable pitch propeller 2, and are fixed by electromagnet 2 and permanent magnet 2.

[0017] Optionally, the UAV is a tail-mounted vertical takeoff and landing fixed-wing UAV.

[0018] Compared with the prior art, the present invention has at least the following beneficial effects: (1) The tail-seat vertical take-off and landing fixed-wing UAV proposed in this invention is equipped with a large aspect ratio wing to ensure high cruise efficiency. Through wing folding technology, the space required for UAV storage and transportation is effectively reduced, making it suitable for different vehicle storage and storage requirements in the sea, land, and air fields. (2) The tail-seat vertical take-off and landing fixed-wing UAV proposed in this invention is equipped with a periodic variable pitch propeller. The propeller disk tilt provides pitch and roll control torque in the vertical state, providing reliable control means for the UAV when switching between vertical and level flight states. This enables the UAV to have strong maneuverability in the vertical state, good wind resistance in the hovering state, and stable and reliable control during vertical take-off and landing. (3) The wing folding and unfolding method proposed in this invention uses inertial force and aerodynamic force coupling. With the assistance of a periodic variable pitch propeller, the wing is first opened or folded by inertial force, and then the aerodynamic force is changed by manipulating the control surface to finely control the unfolding or folding of the wing. The wing can be automatically unfolded without introducing an additional folding and unfolding mechanism, which reduces the structural weight and provides room for improving the performance of the UAV. Attached Figure Description

[0019] The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of the invention.

[0020] The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of the invention.

[0021] Figure 1 This is a schematic diagram of the structure of a vertical take-off and landing fixed-wing UAV according to an embodiment of the present invention; Figure 2 This is a schematic diagram of vertical mode control performed by a cyclic variable-pitch propeller of a vertical take-off and landing fixed-wing UAV according to an embodiment of the present invention. Figure 3 This is a schematic diagram illustrating the execution of a mission by a vertical takeoff and landing fixed-wing UAV according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the wing deployment process of a vertical take-off and landing fixed-wing UAV according to an embodiment of the present invention; Figure 5 This is a schematic diagram of the wing folding process of a vertical take-off and landing fixed-wing UAV according to an embodiment of the present invention; Figure 6 This is a schematic diagram of the structure of a vertical take-off and landing fixed-wing UAV with its wings folded according to an embodiment of the present invention; Figure 7 This is a schematic diagram of the vehicle structure in an embodiment of the present invention; Figure 8 This is a schematic diagram of the vertical take-off and landing fixed-wing UAV structure according to an embodiment of the present invention; Figure 9This is a schematic diagram of the propeller disk formed by the rotation of the propeller of a vertical take-off and landing fixed-wing UAV according to an embodiment of the present invention; Figure 10 This is a schematic diagram of the rotating mechanism of a vertical take-off and landing fixed-wing UAV according to an embodiment of the present invention; Figure 11 This is a schematic diagram of the locking mechanism of a vertical take-off and landing fixed-wing UAV according to an embodiment of the present invention; Figure 12 This is a schematic diagram illustrating the deployment, locking, unlocking, and folding process of the wings of a vertical take-off and landing fixed-wing UAV according to an embodiment of the present invention. Figure 13 This is a schematic diagram of the permanent magnet and electromagnet of the wing of a vertical take-off and landing fixed-wing UAV according to an embodiment of the present invention.

[0022] Figure label: Outer Wing Section 1 101, Mid Wing Section 1 103-1, Outer Wing Section 2 102, Mid Wing Section 2 103-2, Aileron 1 104, Aileron 2 105, Tail 1 201, Tail 2 202, Fuselage 301, Mission Equipment 401, Cyclic Pitch Propeller 1 501-1, Motor 1 501-2, Cyclic Pitch Propeller 2 502-1, Motor 2 502-2, Pitch Control 601, Roll Control 602, Yaw Control 603, Vehicle 701, Propeller Disc 801, Fixed Ring 1 901, Rotating Ring 1 902, Rotating Shaft 1 903, Fixed Lug 1001, Positioning Hole 1002, Pin 1003, Electromagnet 1101, Permanent Magnet 1102 Detailed Implementation To better understand the above-described objectives, features, and advantages of the present invention, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other. Furthermore, the present invention can be implemented in other ways different from those described herein; therefore, the scope of protection of the present invention is not limited to the specific embodiments disclosed below.

[0023] A specific embodiment of the present invention, such as Figure 1-13 A vertical takeoff and landing fixed-wing unmanned aerial vehicle (UAV) is disclosed, comprising: The vertical takeoff and landing fixed-wing UAV includes a main wing, a fuselage 301, and a vertical wing structure; The main wing includes a left wing and a right wing; The left wing includes an outer wing section 101 and a middle wing section 103-1; The right wing includes an outer wing section 2102 and a middle wing section 2103-2; The vertical wing structure includes tail fin one 201 and tail fin two 202; The left wing and right wing respectively include power unit one and power unit two, which are used to provide vertical pull during the vertical take-off and landing phase and thrust during the level flight phase of the UAV. The power unit includes a periodic variable pitch propeller 501-1 and an electric motor 501-2 that is connected to the mid-section wing 103-1 and the periodic variable pitch propeller 501-1 respectively. The second power unit includes a periodic variable pitch propeller 502-1 and an electric motor 502-2 that is connected to the mid-section wing 103-2 and the periodic variable pitch propeller 502-1 respectively. For example, the main wing of the drone is a high aspect ratio wing to ensure high cruise efficiency and endurance. Optionally, the aspect ratio of the main wing is ≥8; Optionally, the left wing, right wing, and vertical wing structure are respectively installed at the tail of the fuselage to support the vertical take-off and landing of the UAV. In one embodiment of the present invention, when the UAV is placed perpendicular to the ground plane, the mid-section wing 103-1, mid-section wing 203-2, tail wing 1 201 and tail wing 202 are all used to support the ground and play a role in supporting take-off and landing.

[0024] Optionally, the mid-section wing 103-1 and the mid-section wing 2 103-2 are respectively installed at the tail end of the fuselage 301; the mid-section wing 103-1 is also connected to the outer section wing 101, the mid-section wing 2 103-2 is also connected to the outer section wing 2 102, and the tail end of the fuselage 301 is also connected to the vertical wing 1 201 and the vertical wing 2 202; The first vertical stabilizer 201 is arranged vertically upward at the tail of the fuselage 301, and the second vertical stabilizer is arranged vertically downward at the tail of the fuselage 301, forming two vertical stabilizer surfaces for maintaining lateral stability.

[0025] Optionally, both the outer wing section 101 and the outer wing section 2 102 are foldable sections; Optionally, the outer wing section one further includes an aileron one 104, and the outer wing section two further includes an aileron two 105; The aileron 104 and aileron 2 105 provide pitch, roll and yaw control torques during the UAV's level flight phase, and provide aerodynamic force in conjunction with the slipstream generated by the rotation of the UAV's periodic variable pitch propeller during the vertical take-off and landing phase.

[0026] Optionally, the fuselage 301 includes a battery, onboard equipment, and a task execution unit; The battery powers the drone and its onboard equipment. The airborne equipment includes, but is not limited to, communication systems, navigation systems, and flight control computers; The communication system is responsible for data communication between the UAV and the control center; the navigation system is responsible for determining the UAV's position, heading, and speed, and guiding the aircraft to fly along a predetermined route; the flight control computer is responsible for data processing during flight.

[0027] Optionally, the task execution unit is located at the head 401 of the fuselage 301, and the task payload is set in the task execution unit according to the different task types of the UAV. For example, the mission payload includes an optoelectronic pod, which receives target coordinates and operating mode commands from the flight control system to achieve intelligent perception and stable tracking of the target.

[0028] Optionally, the periodic variable pitch propeller 501-1 and the periodic variable pitch propeller 502-1 are used to ensure that the UAV has sufficient thrust during the flight state transition process, so as to provide vertical force balance and pitch control of the whole aircraft, while ensuring that the UAV has a certain wind resistance in special mission scenarios.

[0029] Optionally, the periodic variable-pitch propeller 501-1 and motor 501-2 are located on the middle section wing 1, near the side of the outer section wing 1, at the folding junction of the middle section wing 1 and the outer section wing 1; the periodic variable-pitch propeller 502-1 and motor 502-2 are located on the middle section wing 2, near the side of the outer section wing 2, at the folding junction of the middle section wing 2 and the outer section wing 2; the periodic variable-pitch propeller 1 and power unit 1 are symmetrically arranged with respect to the fuselage plane with the periodic variable-pitch propeller 2 and power unit 2. Optionally, the ratio of the distance between the cyclic variable-pitch propeller and the wingtip of the left wing to the span of the left wing is 12-13:20; The ratio of the distance between the cyclic variable-pitch propeller II and the wingtip of the right wing to the span of the right wing is 12-13:20. The periodic variable pitch propeller one and periodic variable pitch propeller two described in this invention achieve the tilting of the propeller disk through periodic pitch change, change the direction of the thrust, and provide sufficient pitch torque control capability, enabling the UAV to achieve autonomous vertical take-off and vertical landing.

[0030] For example, the flight state transition process is the process of the UAV transitioning from vertical takeoff to level flight and the process of the UAV transitioning from level flight to vertical flight when landing after cruise.

[0031] Optionally, the drone also includes locking mechanism one, locking mechanism two, rotating mechanism one and rotating mechanism two, to ensure that the mid-section wing one and mid-section wing two of the drone can remain in a fixed position after being deployed.

[0032] Optionally, the corresponding rotating pair formed between the outer wing section 1 and the middle wing section 1 through the rotating mechanism 1 can rotate freely without an active control device; Optionally, the locking mechanism includes a fixing ear piece 1001, a positioning hole 1002, a pin 1003, and an ear piece groove. The fixed lug 1001 is connected to the upper surface of the middle section wing 1. The positioning hole 1002 is provided on the fixed lug 1001 at one end near the outer section wing 1. The pin 1003 is provided in the lug groove 1 on the outer section wing 1 for connecting the positioning hole 1002. The lug groove 1 is provided on the upper wing surface of the outer section wing 1 on the side near the middle section wing 1 for connecting the lug groove 1. The shape of the lug groove 1 is consistent with the shape of the lug groove 1. The upper surface of the pin 1003 is an inclined plane, wherein the lower side of the inclined plane of the pin 1003 faces the middle section of the wing and the higher side faces the outer section of the wing. The pin 1003 can be moved up and down by a servo motor to change the length of the pin extending from the wing surface.

[0033] The second locking mechanism includes a second fixing ear piece, a second positioning hole, a second pin, and a second ear piece groove; The second fixed lug is connected to the lower surface of the second middle section wing. The second positioning hole is provided on the second fixed lug near the end of the second outer section wing. The second pin is provided in the lug groove on the second outer section wing for connecting the second positioning hole. The lower surface of the second pin is an inclined plane, wherein the lower side of the inclined plane of the second pin faces the middle section of the second wing, and the higher side faces the outer section of the second wing. Optionally, the rotating mechanism includes a fixed ring 901, a rotating ring 902, and a rotating shaft 903; The fixed ring 901 is connected to the middle section wing 1, the rotating ring 902 is fixedly connected to the outer section wing 1, and the rotating shaft 903 is connected to the fixed ring 901 and the rotating ring 1 respectively. The two ends of the rotating shaft 903 are limited by the limiting boss 1 to prevent the outer section wing 1 from displacing along the axial direction.

[0034] Optionally, the second rotating mechanism includes a second fixed ring, a second rotating ring, and a second rotating shaft; The fixed ring 2 is connected to the middle section wing 2, the rotating ring 2 is fixedly connected to the outer section wing 2, and the rotating shaft 2 is connected to the fixed ring 2 and the rotating ring 2 respectively. The two ends of the rotating shaft 2 are limited by the limiting boss 2 to prevent the outer section wing 2 from displacing along the axial direction.

[0035] Optionally, an electromagnet 1101 is provided on the stabilizing surface of the tail fin 201, and a permanent magnet 1102 is arranged on the lower wing surface of the outer wing section. When the left wing is folded, when the outer wing section is close to the wingtip of the vertical tail, the electromagnet 1101 is energized to attract the permanent magnet 1102 on the outer wing section, thereby locking the folded state. The stabilizer of the tail fin 202 is equipped with an electromagnet 2, and the upper surface of the outer wing 2 is arranged with a permanent magnet 2. When the right wing is folded, when the outer wing 2 is close to the wingtip of the vertical tail 2, the electromagnet 2 is energized and attracts the permanent magnet 2 on the outer wing 2, thereby locking the folded state.

[0036] In this invention, the periodic variable-pitch propeller adjusts the angle of attack of the blades at different azimuth angles periodically. Further change the tilt angle of the propeller disk surface This provides additional pitch and roll control torques for the drone; among which, the propeller tilt angle corresponding to the propeller disk tilting upwards towards the fuselage when the drone is in level flight is defined as follows: It is positive; It is understood that the propeller disk surface is a circular area swept by the combined motion trajectories of all the blade tips when the propeller rotates. This plane is perpendicular to the rotation axis of the propeller, and the thrust of the propeller is considered to act uniformly on this disk.

[0037] Periodic variable pitch propellers achieve precise control over the direction of the propeller's aerodynamic resultant force and the fuselage attitude by periodically changing the pitch angle of the rotating blades.

[0038] For example, in each rotation cycle of a periodic variable-pitch propeller, the pitch angle of each blade is dynamically modulated according to its azimuth angle, resulting in differences in the aerodynamic angle of attack of the blades at different positions on the propeller disk, which leads to a corresponding asymmetric distribution of lift.

[0039] This invention generates a lateral aerodynamic torque perpendicular to the propeller shaft and pointing in the desired direction. This torque causes the entire propeller disk to tilt in a specific direction. Ultimately, the total aerodynamic force vector of the propeller disk tilts accordingly, decomposing into a vertical component to overcome gravity and a horizontal component to provide thrust for forward, backward, or lateral flight, thereby enabling the UAV to perform six-degree-of-freedom maneuvering in space in a vertical state. This process, along with the "collective pitch" control used to adjust the total lift, works independently yet collaboratively, together constituting the UAV's unique flight control system.

[0040] The cyclic variable-pitch propeller used in this invention requires the following characteristics: during the vertical takeoff phase, the lift generated by the high-speed, low-pitch configuration must be balanced with gravity to meet hovering requirements; during the high-speed, medium-pitch configuration, the lift generated must provide more than 1.5 times the gravity to meet wind resistance requirements and vertical-to-level flight maneuverability requirements; during the low-speed, medium-pitch configuration, the thrust generated must meet the thrust requirements for cruise; and during the high-speed, high-pitch configuration, the thrust must meet the thrust requirements for maximum speed.

[0041] Another objective of this invention is to provide a method for operating a vertical takeoff and landing fixed-wing unmanned aerial vehicle (UAV), comprising: When the UAV takes off vertically with its wings in the unfolded state, pins 1003 and 2 receive control signals. Pin 1003 protrudes from the first plane of the lug slot of the outer wing 101, and pin 2 protrudes from the second plane of the lug slot of the outer wing 102. The outer wing 101 and the middle wing 103-1 unfold based on the first rotating mechanism and the periodic variable pitch propeller 501-1. The outer wing 102 and the middle wing 103-2 unfold based on the second rotating mechanism and the periodic variable pitch propeller 502-1. The fixed lug 1001 inserts pin 1 into the positioning hole 1002 along the inclined plane of pin 1003, and the fixed lug 2 inserts pin 2 into the positioning hole 2 along the inclined plane of pin 2. When the cyclic variable pitch propeller 1 501-1 and the cyclic variable pitch propeller 2 502-1 tilt in the same direction, they provide pitch control torque for the UAV. When the cyclic variable pitch propeller 1 501-1 and the cyclic variable pitch propeller 2 502-1 of the UAV tilt in opposite directions, they provide the UAV with roll control torque. When the thrust provided by the UAV's cyclic variable pitch propeller 1 501-1 and cyclic variable pitch propeller 2 502-1 are different, a yaw control torque is provided for the UAV. When the UAV is in flight and the wings are in the deployed state, pins 1003 and 2 receive control folding signals and retract. Pin 1 retracts into the wing interior below the plane of the lug slot 1 of the outer wing section 1, and pin 2 retracts into the wing interior below the plane of the lug slot 2 of the outer wing section 2. The outer wing section 1 and the middle wing section 1 fold based on the rotation mechanism 1 and the periodic variable pitch propeller 1, and are fixed by electromagnet 1 and permanent magnet 1. The outer wing section 2 and the middle wing section 2 fold based on the rotation mechanism 2 and the periodic variable pitch propeller 2, and are fixed by electromagnet 2 and permanent magnet 2.

[0042] For example, when the drone takes off vertically with its wings in an undeployed state, pin one and pin two receive control signals. Pin one 1003 protrudes from the plane of the lug slot one of the outer wing section one, and pin two protrudes from the plane of the lug slot two of the outer wing section two. Figure 12 -a; Periodic variable-pitch propeller one and periodic variable-pitch propeller two rotate to generate aerodynamic forces. Outer wing section one and middle wing section one are subjected to corresponding inertial forces based on rotation mechanism one, while outer wing section two and middle wing section two are subjected to corresponding inertial forces based on rotation mechanism two. Based on the aerodynamic forces and corresponding inertial forces, outer wing section one and outer wing section two deploy respectively. Fixed lug one 1001 is inserted into positioning hole one 1002 along the inclined plane of pin one 1003, and fixed lug two is inserted into positioning hole two along the inclined plane of pin two. For example... Figure 12 -b; Pin 1003 and Pin 2 extend under the action of the servo motor to prevent the outer wing sections 1 and 2 from being disturbed and folded, such as Figure 12 -c.

[0043] For example, when the drone is in flight and the wings are in the deployed state, pin one and pin two receive control folding signals. Pin one 1003 protrudes from the plane of the lug slot one of the outer wing section one, and pin two protrudes from the plane of the lug slot two of the outer wing section two, as shown. Figure 12 -d; Pin 1003 retracts and enters the wing interior below the plane of the first lug slot of the outer wing section, while pin 2 retracts and enters the wing interior below the plane of the second lug slot of the outer wing section, as shown. Figure 12 -e; Periodic variable-pitch propeller one and periodic variable-pitch propeller two rotate to generate aerodynamic forces. Outer wing section one and middle wing section one are based on rotation mechanism one, while outer wing section two and middle wing section two are based on rotation mechanism two. They are subjected to corresponding inertial forces. Under the action of inertial forces and aerodynamic forces, outer wing section one and outer wing section two fold, as... Figure 12 -f.

[0044] For example, when the first and second cyclic pitch propellers of the UAV tilt in the same direction, they provide a pitch control torque for the UAV; that is, when the tilt angle of the first cyclic pitch propeller is... The tilt angle of the periodic variable pitch propeller II At that moment, the drone tilted its head up, and the tilt angle of the periodic variable-pitch propeller... The tilt angle of the periodic variable pitch propeller II The drone lowered its head; When the UAV's cyclic variable-pitch propeller one and cyclic variable-pitch propeller two tilt in opposite directions, they provide the UAV with a roll control torque, that is, the tilt angle of cyclic variable-pitch propeller one. The tilt angle of the periodic variable pitch propeller II The drone rolls to the left, and the tilt angle of the periodic variable-pitch propeller is... The tilt angle of the periodic variable pitch propeller II The drone then rolled to the right; When the thrust provided by the first and second cyclic variable-pitch propellers of the UAV is different, a yaw control torque is provided for the UAV; that is, the thrust generated by the first cyclic variable-pitch propeller... The thrust generated by the periodic variable pitch propeller satisfy At that time, the drone veered to the left, satisfying... At that moment, the drone veered to the right.

[0045] In this invention, the automatic folding and unfolding of the wing is controlled by coupling inertial force and aerodynamic force without introducing additional structural weight.

[0046] The automatic folding and unfolding control method for the UAV wings of the present invention does not require providing a direct and fully controllable driving force. It relies on inertial effect to transform the folded wings into the unfolded state, and automatically locks them when the unfolded state is reached.

[0047] In the folding and unfolding process of the wing of this invention, the part that relies on inertial force is as follows: First, the periodic variable-pitch propeller tilts to make the UAV roll around the fuselage axis. The outer wing rolls synchronously with the fuselage and the middle wing. Then, the periodic variable-pitch propeller tilts in the opposite direction, causing the fuselage and the middle wing to stop rolling. At this time, since the outer wing and the middle wing are only connected by a free-rotating axis, due to the inertial effect, the outer wing maintains its original motion state and continues to rotate in the original rotation direction. The unfolding or folding is determined according to the original flight state and rotation direction of the UAV, thus completing the automatic folding or automatic unfolding action.

[0048] The described working method is applicable to both level flight and vertical takeoff and landing phases. Compared with control surface operation, it can generate force control effects without relying on airflow speed. Optionally, the UAV is a tail-mounted vertical takeoff and landing fixed-wing UAV; Alternatively, the drone can be stored folded inside the vehicle; When a mission is required, the UAV takes off vertically in its folded state and hovers in the air. Under the control of the first and second cyclic variable-pitch propellers, it rotates to generate a slipstream. Through inertial force, the outer wing section is deployed. The slipstream rudder is further manipulated to generate aerodynamic force to control the deployment of the outer wing section. When the outer wing section and the middle wing section are in a state of being on the same wing plane, the locking mechanism locks the wing. The wing deployment action is completed by the rotation mechanism. The first and second cyclic variable-pitch propellers complete the transition from vertical mode to level flight mode based on control logic, and then can perform the relevant mission.

[0049] In this invention, the inertial force is that when the mid-section wing comes to an abrupt stop, the outer section wing has mass and therefore inertia. Due to the inertial effect, the outer section wing tends to maintain its original motion. Under the constraint of the pivot connection, the outer section wing rotates around the pivot, thereby completing the deployment action.

[0050] It is understood that the slipstream rudder refers to the control surface that is mainly affected by the propeller slipstream for force manipulation and control. In this invention, the left and right wings are equipped with two control surfaces, aileron 104 and aileron 2 105. When the propeller rotates, the control surface near the wing root will be affected by the propeller slipstream and is regarded as a slipstream rudder.

[0051] In this invention, the inertial force is due to the fact that when the mid-section wing comes to an abrupt stop, the outer section wing has mass and therefore inertia. Due to the inertial effect, the outer section wing tends to maintain its original motion. Under the constraint of the pivot connection, the outer section wing rotates around the pivot, thereby completing the deployment action.

[0052] In this invention, when the flight control system issues a command to execute the wing deployment operation, the periodic variable-pitch propeller first tilts the propeller disk to make the UAV start rolling. After reaching a stable speed, the two propeller disks tilt in opposite directions, causing the fuselage and mid-section wing to come to an abrupt stop. Under the effect of inertia, the outer section wing must maintain its original motion trend. Since the outer section wing and the mid-section wing are connected by a free pivot and are not subject to additional control, the outer section wing will rotate around the pivot under the action of inertia, which manifests as the action of the wing opening.

[0053] Optionally, the aerodynamic force is generated by manipulating the deflection of the control surfaces of aileron 104 and aileron 205 under the slipstream effect produced by the periodic variable pitch propeller 1 and periodic variable pitch propeller 2.

[0054] Optionally, the drone can be loaded into a vehicle 701 that is transported by a carrier in a sea, land, or air environment and stored in a folded state. In one embodiment of the present invention, when a mission is required, the vehicle launches the UAV, which takes off in a folded state. With the assistance of cyclic variable-pitch propeller one and cyclic variable-pitch propeller two, the UAV unfolds its wings by inertial and aerodynamic forces. After locking the wings, it transitions from vertical mode to level flight mode and flies to the mission area to perform the relevant mission. After the mission is completed, the UAV returns to the airspace above the vehicle, transitions from level flight mode to vertical mode, and folds its wings by inertial and aerodynamic forces with the assistance of cyclic variable-pitch propeller one and cyclic variable-pitch propeller two. Under the continuous control of aerodynamic forces, the outer wings are kept tucked to both sides of the fuselage, and the UAV lands vertically on the vehicle. The vehicle then assists in correcting the UAV's position and attitude before it is recovered.

[0055] It is understandable that sliding positioning rods in both the horizontal and vertical directions are installed on the bottom of the vehicle. The position and attitude of the drone are adjusted by pushing it. After the adjustment is completed, the vehicle cover is closed to complete the recovery operation.

[0056] Optionally, the wing deployment process of the drone is as follows: Figure 4 As shown, it specifically includes: The drone takes off vertically in a folded state, leaving the carrier platform, as... Figure 4 -a is shown; In hovering state, the tilt angle of the cyclic variable-pitch propeller one The tilt angle of the periodic variable pitch propeller II This generates a rolling torque. Instruct the drone to roll to the right, as follows: Figure 4 As shown in -b, the drone rotates counterclockwise around its fuselage axis, as... Figure 4 As shown in -b-1; Once a stable speed is reached, the tilt angles of the propeller disks of the first and second periodic pitch propellers are reversed, and the tilt angles are adjusted accordingly. The tilt angle of propeller two When the drone's roll angular velocity At that time, the tilt angle of the propeller disks of both the first and second periodic variable-pitch propellers is reduced to zero. At this point, the fuselage and the first and second mid-section wings cease rolling. Due to inertia, the first and second outer wing sections continue to rotate counterclockwise, opening relative to the fuselage, as if... Figure 4 -c is shown; When the outer wing section is deployed, and the angle between the outer wing section and the corresponding middle wing section is a right angle or an obtuse angle, the airflow on both sides of the outer wing section is less affected by the middle wing section. At this point, under the propeller slipstream, aerodynamic control can be provided to the outer wing section through deflection control surfaces. The aileron deflection angle of the outer wing section... Deflect downwards, that is Aileron deflection angle of the outer wing section Deflect upwards, that is At this point, the outer wing continues to rotate counterclockwise and unfold under aerodynamic forces. When it is aligned with the middle wing on the same wing plane, the locking mechanism engages, completing the wing unfolding process. Figure 4 -d is shown.

[0057] In one embodiment of the present invention, the wing folding process of the drone is as follows: Figure 5 As shown: After transitioning from vertical to horizontal flight, the drone enters a hovering state. When the flight control computer sends a command to begin the landing and recovery maneuver, the locking mechanism unlocks. While hovering, this provides different tilt angles to the left and right cyclic variable-pitch propellers, allowing... , In the generated rolling torque Under the influence of the drone, it rolled to the left, as... Figure 5 As shown in -a, the drone rotates clockwise around its fuselage axis, as... Figure 5 As shown in -a-1; Once a stable rotational speed is reached, the tilt angles of the left and right periodic variable-pitch propellers are controlled to reverse, and the roll rate of the UAV is... The tilt angle of the propeller disk of the left and right periodic variable-pitch propellers is brought to zero, i.e. At this point, the fuselage and mid-section wing stop rolling, but due to inertia, the outer left and right sections of the wing continue to rotate clockwise, folding relative to the fuselage, as if... Figure 5 -b is shown; When the outer wing section is folded to an acute angle with the middle wing section, aerodynamic control of the outer wing section can be provided by deflecting control surfaces under the action of the propeller slipstream. The flap and aileron rudder on the left outer wing section deflects upwards. The flaperon rudder on the right outer section of the wing deflects downwards. At this point, the outer wing section continues to rotate clockwise and fold under aerodynamic forces, tightening towards the fuselage, as... Figure 5 As shown in -c, aerodynamic control is then maintained to prevent the wings from opening during vertical descent. The descent process ends after landing on the vehicle, during which the autonomous folding of the wings is completed.

[0058] This folding and unfolding control method can significantly reduce the space requirements for storing and transporting high aspect ratio UAVs without increasing the weight of the folding and unfolding structure. Figure 6 The images show the drone in its folded state, with 6-a showing a front view, 6-b showing a side view, and 6-c showing a top view. This compact size and lightweight design allows for greater potential for performance improvements in the drone.

[0059] In one embodiment of the present invention, after the mission is completed, the drone returns from the mission area to above the vehicle for autonomous recovery; Under the control of the cyclic variable-pitch propeller, the aircraft transitions from level flight mode to vertical flight mode, thereby unlocking the wings. The outer wing section can rotate around the pivot axis. Under the control of the cyclic variable-pitch propeller, the wing folds through inertial force. Further manipulation of the slipstream rudder uses aerodynamics to continuously control the outer wing section to fold close to the fuselage, completing the wing folding. Subsequently, RTK positioning technology and visual guidance technology can be combined to achieve autonomous landing of the UAV. With the assistance of a vehicle, the position and attitude of the UAV can be adjusted to complete the autonomous recovery of the UAV.

[0060] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A vertical takeoff and landing fixed-wing unmanned aerial vehicle, characterized in that, include: Main wing, fuselage (301) and vertical wing structure; The main wing includes a left wing and a right wing; The left wing includes an outer wing section (101) and a middle wing section (103-1); The right wing includes an outer section wing two (102) and a middle section wing two (103-2); The vertical wing structure includes tail wing one (201) and tail wing two (202). The first mid-section wing (103-1) and the second mid-section wing (103-2) are respectively installed at the tail end of the fuselage (301); the first mid-section wing (103-1) is also connected to the first outer section wing (101), the second mid-section wing (103-2) is also connected to the second outer section wing (102), and the tail end of the fuselage (301) is also connected to the first vertical wing (201) and the second vertical wing (202); The first vertical stabilizer (201) is arranged at the tail of the fuselage (301) in a vertically upward direction, and the second vertical stabilizer is arranged at the tail of the fuselage (301) in a vertically downward direction, forming two vertical stabilizer surfaces to maintain lateral stability. The left wing and right wing respectively include power unit one and power unit two, which are used to provide vertical pull during the vertical take-off and landing phase and thrust during the level flight phase of the UAV. The power unit includes a periodic variable pitch propeller (501-1) and an electric motor (501-2) that is connected to the mid-section wing (103-1) and the periodic variable pitch propeller (501-1) respectively. The second power unit includes a second periodic variable pitch propeller (502-1) and a second motor (502-2) that is connected to the second mid-section wing (103-2) and the second periodic variable pitch propeller (502-1). The periodic variable pitch propeller one and periodic variable pitch propeller two achieve the tilting of the propeller disk through periodic pitch change, change the direction of the thrust, and provide sufficient pitch torque control capability, enabling the UAV to achieve autonomous vertical take-off and vertical landing.

2. The vertical takeoff and landing fixed-wing UAV according to claim 1, characterized in that, Both the outer wing section one (101) and the outer wing section two (102) are foldable sections.

3. The vertical takeoff and landing fixed-wing UAV according to claim 1, characterized in that, The outer wing section one also includes aileron one (104), and the outer wing section two also includes aileron two (105). The aileron one (104) and aileron two (105) provide pitch, roll and yaw control torques for the UAV during level flight, and provide aerodynamic force in combination with the slipstream generated by the rotation of the UAV's periodic variable pitch propeller during vertical take-off and landing.

4. The vertical takeoff and landing fixed-wing UAV according to claim 1, characterized in that, The first periodic variable-pitch propeller (501-1) and the first motor are located on the inner section of the first wing, close to the side of the outer section of the first wing, at the junction of the inner section of the first wing and the outer section of the first wing; the second periodic variable-pitch propeller (502-1) and the second motor (502-2) are located on the inner section of the second wing, close to the side of the outer section of the second wing, at the junction of the inner section of the second wing and the outer section of the second wing; the first periodic variable-pitch propeller and the first motor are arranged symmetrically with respect to the fuselage plane with respect to the second periodic variable-pitch propeller and the second motor.

5. The vertical takeoff and landing fixed-wing UAV according to claim 1, characterized in that, It also includes locking mechanism one, locking mechanism two, rotating mechanism one and rotating mechanism two, which are used to ensure that the mid-section wings one and two of the UAV can remain in a fixed position after they are deployed; The corresponding rotating pair formed by the outer wing section 1 and the middle wing section 1 through the rotating mechanism 1 can rotate freely without an active control device.

6. The vertical takeoff and landing fixed-wing UAV according to claim 5, characterized in that, The locking mechanism includes a fixing ear piece (1001), a positioning hole (1002), a pin (1003), and an ear piece groove; The fixed lug 1 (1001) is connected to the upper surface of the middle section wing 1. The positioning hole 1 (1002) is provided on the fixed lug 1 (1001) near one end of the outer section wing 1. The pin 1 (1003) is provided in the lug groove 1 on the outer section wing 1 for connecting the positioning hole 1 (1002). The lug groove 1 is provided on the upper wing surface of the outer section wing 1 near the middle section wing 1 for connecting the lug groove 1. The shape of the lug groove 1 is consistent with the shape of the lug groove 1. The second locking mechanism includes a second fixing ear piece, a second positioning hole, a second pin, and a second ear piece groove; The second fixed lug is connected to the lower surface of the second middle section wing. The second positioning hole is located on the second fixed lug near the end of the second outer section wing. The second pin is located in the lug groove on the second outer section wing and is used to connect the second positioning hole.

7. The vertical takeoff and landing fixed-wing UAV according to claim 6, characterized in that, The upper surface of the pin (1003) is an inclined plane, wherein the lower side of the inclined plane of the pin (1003) faces the middle section of the wing and the higher side faces the outer section of the wing. The lower surface of the second pin is an inclined plane, wherein the lower side of the inclined plane of the second pin faces the middle section of the second wing, and the higher side faces the outer section of the second wing.

8. The vertical takeoff and landing fixed-wing UAV according to claim 5, characterized in that, The rotating mechanism includes a fixed ring (901), a rotating ring (902), and a rotating shaft (903). The fixed ring 1 (901) is connected to the middle section wing 1, the rotating ring 1 (902) is fixedly connected to the outer section wing 1, and the rotating shaft 1 (903) is connected to the fixed ring 1 (901) and the rotating ring 1 respectively. The two ends of the rotating shaft 1 (903) are limited by the limiting boss 1 to prevent the outer section wing 1 from displacing along the axial direction. The second rotating mechanism includes a second fixed ring, a second rotating ring, and a second rotating shaft; The fixed ring 2 is connected to the middle section wing 2, the rotating ring 2 is fixedly connected to the outer section wing 2, and the rotating shaft 2 is connected to the fixed ring 2 and the rotating ring 2 respectively. The two ends of the rotating shaft 2 are limited by the limiting boss 2 to prevent the outer section wing 2 from displacing along the axial direction.

9. The vertical takeoff and landing fixed-wing UAV according to claim 1, characterized in that, The tail fin (201) is equipped with an electromagnet (1101), and the lower surface of the outer wing is provided with a permanent magnet (1102). When the left wing is folded, when the outer wing is close to the tip of the vertical tail, the electromagnet (1101) is energized to attract the permanent magnet (1102) on the outer wing, thereby locking the folded state. The tail fin 2 (202) is equipped with an electromagnet 2, and the upper surface of the outer wing 2 is arranged with a permanent magnet 2. When the right wing is folded, when the outer wing 2 is close to the wingtip of the vertical tail 2, the electromagnet 2 is energized and attracts the permanent magnet 2 on the outer wing 2, thereby locking the folded state.

10. A method for operating a vertical takeoff and landing fixed-wing unmanned aerial vehicle according to any one of claims 1-9, characterized in that, include: When the UAV takes off vertically and the wings are in the undeployed state, pin 1 (1003) and pin 2 receive control signals. Pin 1 (1003) protrudes from the first plane of the lug slot of the outer wing 1 (101), and pin 2 protrudes from the second plane of the lug slot of the outer wing 2 (102). The outer wing 1 (101) and the middle wing 1 (103-1) are deployed based on the first rotating mechanism and the first periodic variable pitch propeller (501-1). The outer wing 2 (102) and the middle wing 2 (103-2) are deployed based on the second rotating mechanism and the second periodic variable pitch propeller (502-1). The fixed lug 1 (1001) inserts pin 1 into the positioning hole 1 (1002) along the inclined plane of pin 1 (1003), and the fixed lug 2 inserts pin 2 into the positioning hole 2 along the inclined plane of pin 2. When the cyclic variable pitch propeller one (501-1) and the cyclic variable pitch propeller two (502-1) tilt in the same direction, they provide the UAV with pitch control torque. When the UAV's cyclic variable pitch propeller one (501-1) and cyclic variable pitch propeller two (502-1) tilt in opposite directions, they provide the UAV with roll control torque; When the thrust provided by the UAV's cyclic variable pitch propeller one (501-1) and cyclic variable pitch propeller two (502-1) is different, it provides yaw control torque for the UAV; When the UAV is in flight and the wings are in the deployed state, pin 1 (1003) and pin 2 receive control folding signals and retract. Pin 1 (1003) and pin 2 retract respectively. Pin 1 retracts into the wing interior below the plane of the lug slot 1 of the outer wing section 1, and pin 2 retracts into the wing interior below the plane of the lug slot 2 of the outer wing section 2. The outer wing section 1 and the middle wing section 1 are folded based on the rotation mechanism 1 and the periodic variable pitch propeller 1, and are fixed by electromagnet 1 and permanent magnet 1. The outer wing section 2 and the middle wing section 2 are folded based on the rotation mechanism 2 and the periodic variable pitch propeller 2, and are fixed by electromagnet 2 and permanent magnet 2.

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