A wing posture self-adapting adjusting micro bird-simulating bionic flapping-wing aircraft

Abstract

This invention relates to the field of micro biomimetic aircraft technology, and discloses a micro bird-inspired biomimetic flapping-wing aircraft with adaptive wing attitude adjustment. The aircraft includes a fuselage and biomimetic wings located on both sides of the fuselage. The fuselage contains a wing root flapping drive unit, a controller, and a wing attitude adjustment mechanism. The biomimetic wings include a scapular rod, humeral rod, radial rod, carpal rod, and finger rod connected sequentially from the wing root to the wingtip. This micro bird-inspired biomimetic flapping-wing aircraft achieves basic periodic flapping of the biomimetic wings through the wing root flapping drive unit. Through the cooperation of a traction rope, a winding wheel, a sliding wheel, a sliding plate, a track plate, and flexible bone-like rods, the radial rod, carpal rod, and finger rod can generate recoverable elastic bending under the eccentric traction of the traction rope. This allows the biomimetic wings to form different wing surface curvatures and wingtip attitudes under conditions of downward flapping, upward flapping, turning, and airflow disturbance.

Description

Technical Field

[0001] This invention relates to the field of micro biomimetic aircraft technology, and in particular to a micro bird-inspired biomimetic flapping-wing aircraft with adaptive wing attitude adjustment. Background Technology

[0002] Existing micro bird-inspired flapping-wing aircraft typically use motors, gears, crank-connecting rods, or servos to drive the wings in periodic flapping motions. Some structures also use articulated motors or linkage mechanisms to adjust the wingtip angle, achieving certain flapping, steering, or attitude correction functions. However, these structures mostly rely on the fixed-angle swinging or preset trajectory movement of rigid rods. The wing surface curvature changes little during upward flapping, downward flapping, and airflow disturbances. The outer wing section and wingtip section cannot form continuous elastic deformation similar to a bird's wing, resulting in a relatively mechanical flapping action and insufficient airflow adaptability and attitude adjustment capabilities.

[0003] Existing micro flapping wing structures mainly address the issue of whether the wings can flap back and forth, but they do not adequately consider the dynamic adjustment of wing curvature, wingtip attitude, and local stress state during flight. If multiple joint motors are used to adjust the wing attitude separately, it is easy to increase weight, energy consumption, and control complexity, which is not conducive to miniaturization. If only the flexible wing surface is passively deformed, it is difficult to actively change the degree of wing curvature and wingtip attitude, making it difficult for the aircraft to form an appropriate wing attitude in time under crosswinds, updrafts, downdrafts, or attitude disturbances. Summary of the Invention

[0004] The technical problem to be solved by the present invention is that the existing technology has the disadvantage that the wing surface is difficult to produce controllable elastic bending according to the flight stage and airflow state during the flapping process. To this end, we propose a micro bird-inspired bionic flapping wing aircraft with adaptive wing attitude adjustment.

[0005] To achieve the above objectives, this application adopts the following technical solution: a micro bird-like bionic flapping-wing aircraft with adaptive wing attitude adjustment, comprising a fuselage and bionic wings disposed on both sides of the fuselage. The fuselage contains a wing root flapping drive unit, a controller, and a wing attitude adjustment mechanism. The bionic wings include a scapular rod, an humeral rod, a radial rod, a wrist rod, and a finger rod connected sequentially from the wing root to the wingtip. The wing root flapping drive unit is connected to the scapular rod or the humeral rod for driving the bionic wings to flap periodically. At least one of the radial rod, wrist rod, and finger rod is a flexible bone-like rod with an elastic bending section. The wing attitude adjustment mechanism includes multiple traction ropes, multiple winding reels, and a lever arm adjustment assembly. Each winding reel is controlled by the controller to independently retract. The corresponding traction rope is wound or released. The traction rope extends along the bionic wing and is arranged off-center from the neutral axis of the corresponding flexible bone-like rod. The end of the traction rope is connected to the upper or lower side of the corresponding flexible bone-like rod so as to generate eccentric traction on the corresponding flexible bone-like rod and cause it to produce a recoverable elastic bend when wound up. The lever arm adjustment component is set on the radial rod and the wrist rod, including a through groove, a track plate set in the through groove, a sliding plate slidably set on the track plate, and a sliding wheel connected to the sliding plate. The traction rope is wound around or abutted against the sliding wheel. The sliding wheel moves with the sliding plate to change the traction angle of the traction rope and the eccentric distance of the traction rope relative to the neutral axis of the flexible bone-like rod, so that the bionic wing forms an adjustable wing surface curvature and wingtip attitude during flapping.

[0006] Preferably, the humeral member is a high-rigidity main force transmission member used to bear the flapping load at the wing root, and at least one of the radial member, wrist member, and finger member is made of carbon fiber composite sheet, glass fiber rod, nylon elastic rod, thin-walled composite rod, or elastic alloy rod, and forms the elastic bending section in its length direction.

[0007] Preferably, the multiple traction ropes include an upper traction rope group and a lower traction rope group. The upper traction rope group is connected to the upper region of the corresponding flexible bone-like rod, and the lower traction rope group is connected to the lower region of the corresponding flexible bone-like rod. The controller differentially controls the extension and retraction of the upper and lower traction rope groups, so that the corresponding flexible bone-like rod forms an upward arch, downward arch, flattening, or wingtip folding wing posture.

[0008] Preferably, the winding wheel is rotatably mounted on the transmission rod, and each winding wheel is connected to a micro geared motor, servo motor, stepper motor or transmission component with self-locking function. The outer circumferential surface of the winding wheel is provided with an annular winding groove. One end of the pull rope is fixed to the winding wheel. When the winding wheel rotates in the forward direction, the pull rope is wound up, and when it rotates in the reverse direction, the pull rope is released.

[0009] Preferably, the winding reel is connected to a self-locking gearbox, worm gear reducer, brake pad, or electromagnetic locking device for maintaining the winding position of the pull rope; the pull rope is also in cooperation with an elastic pretensioner, which is used to keep the pull rope in a pre-tensioned state when the winding reel releases the pull rope.

[0010] Preferably, the shielding box, scapular rod, humeral rod, radial rod, wrist and palm rod, or finger rod are provided with wire holes, wire tubes, or guide rings. The traction rope extends along the bionic wing through the wire holes, wire tubes, or guide rings to limit the direction of the traction rope and reduce the traction rope's wear or entanglement during winding and release.

[0011] Preferably, the sliding plate is driven to move along the track plate by a miniature lead screw, rack and pinion transmission component, traction rope transmission component, miniature servo motor or elastic reset structure. The sliding plate drives the sliding wheel to change position in the direction of approaching or moving away from the neutral axis of the flexible bone-like rod, so as to adjust the bending moment generated by the traction rope on the flexible bone-like rod.

[0012] Preferably, a ruler is provided between the humeral arm and the radial arm, and a connecting groove is provided on the side of the radial arm. One end of the ruler is connected to the humeral arm, and the other end of the ruler is slidably embedded in the connecting groove, so as to provide auxiliary support for the forearm segment and release relative displacement when the radial arm undergoes elastic bending or relative displacement.

[0013] Preferably, the outer sides of the humeral arm, radial arm, wrist arm, and finger arm are covered with nylon sheaths. The upper surface of the nylon sheaths is provided with upper wings, and the lower surface of the nylon sheaths is provided with lower wings. Adjusting rods are connected to both sides of the wrist arm, and the adjusting rods are provided with secondary wings. The secondary wings cover part of the upper surface of the upper wings to form a continuously changing wing surface curvature when the flexible bone-like rods are elastically bent.

[0014] Preferably, the controller is configured to control the movement of the winding wheel and the sliding plate according to the flapping phase of the bionic wing, so that the radial stick, wrist stick, or finger stick forms an extended or arched wing posture during the downward flapping phase, and the wrist stick or finger stick forms a downward deflection, folding, or reduced frontal area wing posture during the upward flapping phase; and to control the amount of extension or retraction of the traction rope or the position of the sliding wheel of the bionic wings on both sides of the fuselage respectively, so that the bionic wings on both sides form the same wing surface curvature for stable flight, or form different wing surface curvatures for turning, attitude correction, or airflow disturbance compensation.

[0015] The technical effects and advantages of this invention are as follows: In this invention, the basic periodic flapping of the bionic wing is achieved through a wing root flapping drive unit. The coordination of a traction rope, a winding wheel, a sliding wheel, a sliding plate, a track plate, and flexible bone-like rods allows the radial rod, wrist rod, and finger rod to generate recoverable elastic bending under the eccentric traction of the traction rope. This enables the bionic wing to form different wing surface curvatures and wingtip attitudes during downward flapping, upward flapping, turning, and airflow disturbance states. The sliding wheel, moving with the sliding plate, changes the traction angle of the traction rope and its eccentric distance relative to the neutral axis of the rods, thus changing the lever arm under the same traction tension and adjusting the degree of bending of the rods. Therefore, this invention reduces the need for multiple joint motors on the outer wing section, lowers the weight and control complexity of the micro-aircraft, and allows the wing to move beyond a single rigid flapping trajectory, achieving a continuous elastic wing attitude closer to bird flight, improving airflow adaptability, attitude adjustment capability, and bionic flight effect during flight. Attached Figure Description

[0016] The disclosure of this invention is illustrated with reference to the accompanying drawings. It should be understood that the drawings are for illustrative purposes only and are not intended to limit the scope of protection of this invention. In the drawings, the same reference numerals are used to refer to the same parts: Figure 1 This is a schematic diagram of the overall structure of the miniature bird-inspired bionic flapping-wing aircraft of the present invention.

[0017] Figure 2 This is a schematic diagram of the overall structure from another perspective of the present invention.

[0018] Figure 3 This is a lateral structural diagram of the scapular rod, ruler rod, and adjusting rod of the present invention.

[0019] Figure 4 This is a schematic diagram of the scapular and humeral shafts of the present invention.

[0020] Figure 5 This is a schematic diagram of the structure of the adjusting rod and the ruler rod of the present invention.

[0021] Figure 6 This is a schematic diagram of the assembly structure of the sliding plate, track plate and sliding wheel of the present invention.

[0022] Figure 7 This is a partially enlarged structural schematic diagram of the internal force arm adjustment assembly of the radius and wrist lever of the present invention.

[0023] Figure 8 This is a schematic diagram of the connection structure of the biomimetic wing skeleton of the present invention.

[0024] Figure 9 This is an exploded structural diagram of the present invention.

[0025] Figure 10This is a schematic diagram illustrating the mechanical analysis of the changes in the angle of the pulling rope and the change in the lever arm in an embodiment of the present invention.

[0026] Figure 11 This is a schematic diagram of the distribution of the traction ropes in an embodiment of the present invention.

[0027] Legend: 1. Shielded housing; 2. Nylon sheath; 3. Upper wing; 4. Secondary wing; 5. Lower wing; 6. Adjusting rod; 7. Ruler rod; 8. Shoulder rod; 9. Arm rod; 10. Radius rod; 11. Wrist rod; 12. Finger rod; 13. Connecting groove; 14. Through groove; 15. Sliding piece; 16. Track piece; 17. Pulley; 18. Pull rope; 19. Transmission rod; 20. Winding reel. Detailed Implementation

[0028] It is readily understood that, based on the technical solution of this invention, those skilled in the art can propose various interchangeable structural methods and implementations without altering the essential spirit of the invention. Therefore, the following detailed embodiments and accompanying drawings are merely illustrative examples of the technical solution of this invention and should not be considered as the entirety of the invention or as limitations or restrictions on the technical solution of this invention.

[0029] Reference Figure 1-11 As shown, the present invention provides a technical solution: a micro bird-like bionic flapping wing aircraft with adaptive wing attitude adjustment. The shielding box 1 is used to be embedded in the body of the bionic bird. The interior of the shielding box 1 forms an installation space for setting up a controller, a wing root flapping drive unit and a traction drive assembly. The shielding box 1 protects the internal electronic control components and transmission components on the one hand, and serves as the wing root mounting base for the wing skeleton, so that the wing skeleton can be stably connected to the side of the bionic bird body.

[0030] One end of the scapular rod 8 is connected to the shielding box 1, and the other end of the scapular rod 8 is connected to the humeral rod 9. The end of the humeral rod 9 away from the scapular rod 8 is connected to the radial rod 10. The end of the radial rod 10 away from the humeral rod 9 is connected to the carpal rod 11. The end of the carpal rod 11 away from the radial rod 10 is connected to the finger rod 12. The scapular rod 8, humeral rod 9, radial rod 10, carpal rod 11 and finger rod 12 form a segmented skeleton of a bird-like wing. The scapular rod 8 mainly undertakes the function of supporting the wing root, the humeral rod 9 mainly undertakes the function of transmitting flapping power, the radial rod 10 mainly undertakes the function of supporting the mid-section wing surface and adjusting curvature, the carpal rod 11 mainly undertakes the function of adjusting the attitude of the outer wing, and the finger rod 12 mainly undertakes the function of supporting the wingtip attitude and wingtip feathers.

[0031] The wing root flapping drive unit is connected to the scapular rod 8 or the humeral rod 9 to drive the wing skeleton to make periodic up-and-down flapping movements relative to the bionic bird body. The wing root flapping drive unit can be a micro motor, a geared motor, a servo motor, an eccentric wheel mechanism, a crank-connecting rod mechanism, or a gear transmission mechanism. The power output of the wing root flapping drive unit is mainly used to form the basic flapping motion of the entire wing, causing the humeral rod 9 to drive the radial rod 10, the wrist rod 11, the finger rod 12, and the feather structure installed on its outer side to make periodic oscillations. The humeral rod 9 is located close to the wing root. Since the humeral rod 9 bears the main force transmission function, the humeral rod... 9. Preferably, lightweight rods with high stiffness are used, such as carbon fiber rods, thin-walled aluminum alloy rods, or reinforced composite material rods. At least one of the radius rod 10, wrist rod 11, and finger rod 12 is configured as a flexible bone-like rod. The flexible bone-like rod has an elastic bending section that can repeatedly recover. When the traction rope 18 applies eccentric traction to the elastic bending section, the rod can produce an elastic bending that deflects in the traction direction. The flexible bone-like rod can be made of carbon fiber composite sheet, glass fiber rod, nylon elastic rod, thin-walled composite rod, elastic alloy rod, or lightweight material with elastic recovery capability.

[0032] To ensure the forearm remains stable during posture changes, a ruler 7 is provided between the humeral bar 9 and the radial bar 10. The radial bar 10 has a connecting groove 13 on its side. One end of the ruler 7 is connected to the humeral bar 9, and the other end of the ruler 7 is embedded in the connecting groove 13 and can slide along the connecting groove 13. When the radial bar 10 undergoes elastic bending or relative position change under the action of the tension rope 18, the ruler 7 can provide auxiliary support. At the same time, the relative displacement between the radial bar 10 and the humeral bar 9 is released through the connecting groove 13, reducing the jamming of the forearm during flapping and deformation.

[0033] Adjustment rods 6 are connected to both sides of the wrist bar 11. The adjustment rods 6 are used to support the wing structure near the wrist section and maintain the deployment state of the ailerons 4 when adjusting the attitude of the outer wing section. The finger rod 12 is located at the far end of the wrist bar 11. The finger rod 12 can be set as a thin and flexible rod, so that the wingtip area can form a more natural bending and attitude change under the action of the traction rope 18. The humerus bar 9, radial bar 10, wrist bar 11 and finger rod 12 are covered with a nylon sleeve 2. The nylon sleeve 2 is used to connect the wing structure on the outside of multiple rods into a continuous wing surface and follow the rod. The bending produces adaptive deformation. The upper surface of the nylon sleeve 2 is provided with upper wings 3, the lower surface of the nylon sleeve 2 is provided with lower wings 5, and the upper surface of the adjusting rod 6 is provided with secondary wings 4, which cover part of the upper surface of the upper wings 3. The upper wings 3, secondary wings 4 and lower wings 5 ​​can be made of lightweight flexible sheets, feather-like materials, elastic films or composite sheets. Through the cooperation of the nylon sleeve 2 and the multi-layer wings, the wing surface can form a continuous wing surface curvature when the rod is bent, reducing the stiff motion pattern generated by ordinary rigid wing plates when flapping wings.

[0034] The shielded housing 1 is equipped with a traction drive assembly, which includes a transmission rod 19, a winding wheel 20, and a drive component corresponding to the winding wheel 20. The transmission rod 19 can serve as the mounting shaft or support shaft of the winding wheel 20. Multiple sets of winding wheels 20 are rotatably mounted on the transmission rod 19 through bearings. Each winding wheel 20 can rotate independently relative to the transmission rod 19. Each winding wheel 20 is connected to a drive component. The drive component can be a micro geared motor, servo motor, stepper motor, or a micro transmission assembly with a self-locking function. Through the above structure, the controller can control the rotation of different winding wheels 20 respectively, thereby controlling the winding amount and release amount of different traction ropes 18 respectively.

[0035] In another structure, the drive rod 19 can also serve as the drive shaft, with some winding pulleys 20 fixed to the drive rod 19 for synchronously winding a set of pull ropes 18; the remaining winding pulleys 20 are connected to the drive rod 19 via a clutch, a separate motor, or a one-way transmission component for independently adjusting the corresponding pull ropes 18. This structure is suitable for situations where some wing attitudes require synchronous control and some wing attitudes require individual control.

[0036] Each winding wheel 20 has an annular winding groove on its outer circumference. The pull rope 18 is wound inside the annular winding groove. The winding wheel 20 is also provided with a rope end fixing hole, a wire pressing groove or a wire clamp. One end of the pull rope 18 is inserted into the rope end fixing hole and then fixed to the winding wheel 20 by a wire pressing screw, a wire pressing plate, adhesive bonding or knotting. When the winding wheel 20 rotates in the first direction, the pull rope 18 winds around into the annular winding groove one turn at a time, reducing the effective outward extension length of the pull rope 18 and increasing the pulling force on the corresponding rod. When the winding wheel 20 rotates in the opposite direction, the pull rope 18 is released from the annular winding groove. As the effective extension length of the pull rope 18 increases, the pulling force on the corresponding rod decreases. To prevent the pull rope 18 from becoming loose or tangled after release, a line-blocking edge can be provided on one side of the winding wheel 20. The annular winding groove can be set as a spiral guide groove or a groove with a certain width. After the pull rope 18 is led out from the winding wheel 20, it enters the shoulder rod 8, humerus rod 9, radius rod 10, wrist rod 11 or finger rod 12 through the wire hole, wire tube or low-friction guide ring. The wire hole, wire tube or guide ring can restrict the direction of the pull rope 18 and reduce the friction or tangling of the pull rope 18 inside the machine body.

[0037] To ensure that the pull rope 18 maintains basic tension in the released state, it can be coupled with an elastic pretensioner. This elastic pretensioner can be a tension spring, torsion spring, elastic rope segment, or elastic sheet. It can be installed between the winding reel 20 and the pull rope 18, or near the distal fixed position of the pull rope 18. Through the elastic pretensioner, the pull rope 18 maintains a certain tension when the winding reel 20 is released, preventing slack from affecting the next winding. The drive mechanism of the winding reel 20 can also be a worm gear reducer, a self-locking gearbox, a brake pad, or an electromagnetic locking device, allowing the winding reel 20 to maintain its current position when it stops rotating. To prevent the traction rope 18 from automatically retracting under airflow load or the rebound force of the rod, the traction rope 18 extends along the wing skeleton and is arranged off-center from the neutral axis of the corresponding flexible skeletal rod. The traction rope 18 can be configured as an upper traction rope group and a lower traction rope group. The upper traction rope group is arranged close to the upper side of the rod, and the lower traction rope group is arranged close to the lower side of the rod. When the upper traction rope group is wound up, the corresponding rod will have an elastic bending tendency to arch upward; when the lower traction rope group is wound up, the corresponding rod will have an elastic bending tendency to bend downward or retract. By differentially winding and unwinding the upper and lower traction rope groups, the local curvature of the wing skeleton, the wingtip angle, and the attitude of the outer wing section can be changed.

[0038] In one embodiment, the upper traction rope group includes multiple traction ropes 18. These ropes 18 extend from the shielded housing 1 to the humeral arm 9, radial arm 10, pawl arm 11, and finger arm 12, respectively. The traction rope 18 fixed to the humeral arm 9 is used for pre-tensioning and minor attitude correction near the wing root. The traction rope 18 fixed to the radial arm 10 is used to control the curvature of the mid-section wing surface. The traction rope 18 fixed to the pawl arm 11 is used to control the degree of bending of the outer wing section and the wingtip angle of attack. The traction rope 18 fixed to the finger arm 12 is used to control the deployment, retraction, or upward movement of the wingtip area. The lower traction rope group can adopt the same arrangement and is fixed to the lower area of ​​the aforementioned rods.

[0039] A through groove 14 is provided in the middle of the radial rod 10, and a track plate 16 is provided in the through groove 14. The track plate 16 extends along the length of the radial rod 10. A sliding plate 15 is slidably mounted on the track plate 16. The sliding plate 15 can be driven by a miniature screw, rack, slider traction rope, miniature servo motor, or elastic reset structure to move back and forth along the track plate 16. A sliding wheel 17 is connected to the sliding plate 15. A traction rope 18 is wound around the sliding wheel 17 or in contact with the outer circumference of the sliding wheel 17. The sliding wheel 17 is used to change the position of the traction rope 18 relative to the radial rod 10. When the sliding plate 15 moves along the track plate 16... The position of the pulley 17 changes, causing the eccentricity of the pull rope 18 relative to the neutral axis of the radius 10 to change. When the pulley 17 is far away from the neutral axis of the radius 10, the pull rope 18 forms a larger bending moment on the radius 10, and a larger bending curvature can be obtained under the same pulling force. When the pulley 17 is close to the neutral axis of the radius 10, the bending moment formed by the pull rope 18 on the radius 10 decreases, the degree of bending of the radius 10 decreases, and the wing surface tends to be relatively flat. Therefore, the bending curvature of the radius 10 can be adjusted not only by the length of the pull rope 18, but also by the position of the pulley 17.

[0040] The wrist arm 11 can also be equipped with a through groove 14, a track plate 16, a sliding plate 15, and a sliding wheel 17. Since the wrist arm 11 is located in the outer wing section, the bending and twisting trend of the outer wing section has a significant impact on the flight attitude. By setting the sliding wheel 17 in the wrist arm 11, the eccentric distance between the traction rope 18 and the wrist arm 11 can be changed, so that the outer wing section can form different wingtip attitudes under different flight conditions. For example, when the aircraft needs to increase the down-blow lift, the upward curvature of the wrist arm 11 can be increased; when the aircraft needs to reduce the up-blow drag, the wrist arm 11 and the finger stick 12 can be made to form a downward deflection or folding attitude; when the aircraft is disturbed by crosswinds, the different curvatures of the wrist arm sections of the left and right wings can be used to assist in attitude correction.

[0041] During flight, the wing root flapping drive unit first drives the scapular rod 8 or the humeral rod 9 to periodically swing up and down. The humeral rod 9 drives the radial rod 10, the wrist rod 11, the finger rod 12, and the feather structure to complete the basic flapping action. At the same time, the controller controls the winding wheel 20 to move according to the preset flapping phase, flight attitude signal, or airflow disturbance state. When the winding wheel 20 winds up the pull rope 18, the pull rope 18 generates eccentric traction on the corresponding flexible bone-like rod, causing the corresponding rod to bend elastically. When the winding wheel 20 releases the pull rope 18, the corresponding rod recovers or forms a reverse bend by relying on its own elastic recovery ability and the adjustment effect of the pull rope 18 on the opposite side.

[0042] When the wing is in the downward flapping phase, the controller controls the wing root flapping drive unit to drive the wing downward, and at the same time controls the winding wheel 20 corresponding to the upper side of the radial rod 10, the wrist rod 11 and the finger rod 12 to wind up the pull rope 18, so that the middle section of the wing surface, the outer wing section and the wingtip section form an extended or arched wing posture. At this time, the upper wing 3, the aileron 4 and the lower wing 5 form a large effective load-bearing area with the nylon cover 2, which is conducive to improving the lift and thrust during the downward flapping phase.

[0043] When the wings are in the flapping phase, the upper tether rope 18 of the controller is released, or the lower tether rope 18 is wound up, so that the wrist rod 11 and finger rod 12 drive the outer wing section and wingtip section to form a downward deflection or folding wing posture. This can reduce the windward area in the flapping phase, reduce airflow resistance, and make the flapping process closer to the downward flapping and drag reduction state of birds in flight.

[0044] When the aircraft is subjected to crosswinds, updrafts, downdrafts, or attitude disturbances, the controller can change the winding amount of different traction ropes 18. If it is necessary to increase the load-bearing capacity of one wing, the controller controls the traction ropes 18 corresponding to the radial rod 10, wrist rod 11, and finger rod 12 on that side to form a larger upward arch curvature. If it is necessary to reduce the aerodynamic effect of one wing, the controller controls the outer wing section on that side to form a smaller curvature or a folded state. By using different bending curvatures of the left and right wings, the controller can assist the aircraft in completing turns, disturbance rejection, and attitude correction.

[0045] When the controller determines that it is necessary to improve the adaptability of the outer wing section to airflow, the controller drives the corresponding winding wheel 20 to wind up or release the traction rope 18 corresponding to the wrist lever 11. On the other hand, it drives the sliding plate 15 to move along the track plate 16, so that the sliding wheel 17 changes the lever arm of the traction rope 18. Through the combination of length adjustment and lever arm adjustment, the wrist lever 11 can produce more delicate elastic bending changes, thereby driving the aileron 4 and upper wing 3 to form a more continuous wing surface curvature. When the wing surface needs to maintain greater stiffness, the sliding plate 15 can drive the sliding wheel 17 closer to the neutral axis of the rod, so that the bending moment generated by the traction rope 18 on the rod is reduced and the bending amplitude of the rod is reduced. When the wing surface needs to have strong compliance, the sliding plate 15 can drive the sliding wheel 17 away from the neutral axis of the rod, so that the traction rope 18 generates a larger bending moment on the rod, and the rod can form obvious bending even under a small pulling force. This structure enables the aircraft to adjust the wing surface curvature and wingtip attitude without increasing the number of articulated motors in the outer wing section.

[0046] The pull rope 18 can also preload and assist in stabilizing the humeral bar 9. As the main force transmission member of the wing root, the humeral bar 9 is easily affected by inertial force and transmission clearance when the wing root flapping drive unit changes direction. By applying appropriate preload to the pull rope 18 corresponding to the humeral bar 9, the vibration of the humeral bar 9 during the changing process can be reduced, making the power output of the wing root more stable. Compared with the radial bar 10, the wrist bar 11 and the finger bar 12, the elastic bending amplitude of the humeral bar 9 can be smaller to ensure that the wing root structure has sufficient support strength.

[0047] The radiator 10 is mainly used to form the mid-section wing surface curvature. After the radiator 10 is elastically bent by the pull rope 18, the nylon sheath 2 drives the upper wing 3 and lower wing 5 to form a relatively smooth mid-section wing surface. The wrist lever 11 is mainly used to change the attitude of the outer wing section. The bending of the wrist lever 11 can change the angle of attack and torsional trend near the wingtip. The finger lever 12 is mainly used to control the wingtip area. The elastic bending of the finger lever 12 under the action of the pull rope 18 can drive the wingtip wings to unfold, rise, deflect downward or fold, making the wingtip movement more natural.

[0048] The bird-like segmented skeleton is formed by the humeral rod 9, radial rod 10, wrist rod 11, and finger rod 12. The flexible bone-like rods and the pull rope 18 enable the elastic bending of the rod segments. The pull rope 18 can be independently wound and released by the winding wheel 20. The eccentric distance and force arm of the pull rope 18 can be changed by the sliding plate 15, the track plate 16, and the sliding wheel 17. As a result, the bionic wing can form various wing attitudes such as arching, arching, flattening, wingtip pointing, and wingtip folding during flapping. This gives the micro bird-like bionic flapping wing aircraft better wing attitude adaptability, flight stability, and bionic effect under the conditions of flapping, turning, and airflow disturbance.

[0049] The technical scope of this invention is not limited to the content described above. Those skilled in the art can make various modifications and variations to the above embodiments without departing from the technical concept of this invention, and all such modifications and variations should fall within the protection scope of this invention.

Claims

1. A micro bird-inspired bionic flapping-wing aircraft with adaptive wing attitude adjustment, comprising a fuselage and bionic wings disposed on both sides of the fuselage, characterized in that: The body contains a wing root flapping drive unit, a controller, and a wing attitude adjustment mechanism. The bionic wing includes a scapular rod, humeral rod, radial rod, carpal rod, and finger rod connected sequentially from the wing root to the wingtip. The wing root flapping drive unit is connected to the scapular rod or humeral rod for driving the bionic wing to flap periodically. At least one of the radial rod, carpal rod, and finger rod is a flexible bone-like rod with an elastic bending section. The wing attitude adjustment mechanism includes multiple traction ropes, multiple winding reels, and a lever arm adjustment assembly. Each winding reel is controlled by the controller to independently wind or release the corresponding traction rope. The traction ropes extend along the bionic wing and deviate from the corresponding flexible bone-like rod. The neutral axis of the rod is arranged such that the end of the traction rope is connected to the upper or lower side of the corresponding flexible bone-like rod, so that it can generate eccentric traction on the corresponding flexible bone-like rod and cause it to produce a recoverable elastic bend during winding; the lever arm adjustment assembly is set on the radial rod and the wrist rod, including a through groove, a track plate set in the through groove, a sliding plate slidably set on the track plate, and a sliding wheel connected to the sliding plate. The traction rope is wrapped around or abuts against the sliding wheel. The sliding wheel moves with the sliding plate to change the traction angle of the traction rope and the eccentric distance of the traction rope relative to the neutral axis of the flexible bone-like rod, so that the bionic wing can form an adjustable wing surface curvature and wingtip attitude during flapping.

2. The micro bird-inspired bionic flapping-wing aircraft with adaptive wing attitude adjustment according to claim 1, characterized in that: The humeral member is a high-rigidity main force transmission member used to bear the flapping load at the wing root. At least one of the radial member, wrist member, and finger member is made of carbon fiber composite sheet, glass fiber rod, nylon elastic rod, thin-walled composite rod, or elastic alloy rod, and forms the elastic bending section in its length direction.

3. The micro bird-inspired bionic flapping-wing aircraft with adaptive wing attitude adjustment according to claim 1, characterized in that: The multiple traction ropes include an upper traction rope group and a lower traction rope group. The upper traction rope group is connected to the upper area of ​​the corresponding flexible bone-like rod, and the lower traction rope group is connected to the lower area of ​​the corresponding flexible bone-like rod. The controller differentially controls the extension and retraction of the upper and lower traction rope groups, so that the corresponding flexible bone-like rod forms an upward arch, downward arch, flattening, or wingtip folding wing posture.

4. The micro bird-inspired bionic flapping-wing aircraft with adaptive wing attitude adjustment according to claim 1, characterized in that: The winding wheel is rotatably mounted on the transmission rod. Each winding wheel is connected to a micro geared motor, servo motor, stepper motor, or transmission component with self-locking function. The outer circumferential surface of the winding wheel is provided with an annular winding groove. One end of the pull rope is fixed to the winding wheel. When the winding wheel rotates in the forward direction, it winds up the pull rope and when it rotates in the reverse direction, it releases the pull rope.

5. The micro bird-inspired bionic flapping-wing aircraft with adaptive wing attitude adjustment according to claim 4, characterized in that: The winding reel is connected to a self-locking gearbox, worm gear reducer, brake pads, or electromagnetic locking device for maintaining the winding position of the pull rope; the pull rope is also in cooperation with an elastic pretensioner, which is used to keep the pull rope in a pre-tensioned state when the winding reel releases the pull rope.

6. The micro bird-inspired bionic flapping-wing aircraft with adaptive wing attitude adjustment according to claim 1, characterized in that: The shielding box, scapular rod, humeral rod, radial rod, wrist and palm rod, or finger rod are provided with wire holes, wire tubes, or guide rings. The traction rope extends along the bionic wing through the wire holes, wire tubes, or guide rings to limit the direction of the traction rope and reduce the traction rope's wear or entanglement during winding and release.

7. The micro bird-inspired bionic flapping-wing aircraft with adaptive wing attitude adjustment according to claim 1, characterized in that: The sliding plate is driven by a miniature lead screw, rack and pinion transmission component, traction rope transmission component, miniature servo motor or elastic reset structure to move along the track plate. The sliding plate drives the sliding wheel to change position in the direction of approaching or moving away from the neutral axis of the flexible bone-like rod to adjust the bending moment generated by the traction rope on the flexible bone-like rod.

8. The micro bird-inspired bionic flapping-wing aircraft with adaptive wing attitude adjustment according to claim 1, characterized in that: A ruler is provided between the humerus and the radius. A connecting groove is provided on the side of the radius. One end of the ruler is connected to the humerus, and the other end of the ruler is slidably embedded in the connecting groove to provide auxiliary support for the forearm segment and release relative displacement when the radius undergoes elastic bending or relative displacement.

9. The micro bird-inspired bionic flapping-wing aircraft with adaptive wing attitude adjustment according to claim 1, characterized in that: The outer sides of the humeral, radial, wrist, and finger rods are covered with nylon sheaths. The upper surface of the nylon sheaths is provided with upper wings, and the lower surface of the nylon sheaths is provided with lower wings. Adjusting rods are connected to both sides of the wrist rods, and secondary wings are provided on the adjusting rods. The secondary wings cover part of the upper surface of the upper wings to form a continuously changing wing surface curvature when the flexible bone-like rods are elastically bent.

10. The micro bird-inspired bionic flapping-wing aircraft with adaptive wing attitude adjustment according to claim 1, characterized in that: The controller is configured to control the movement of the winding wheel and sliding plate according to the flapping phase of the bionic wings. During the downward flapping phase, the radial stick, wrist stick, or finger stick forms an extended or arched wing posture. During the upward flapping phase, the wrist stick or finger stick forms a downward deflection, folding, or reduced frontal area wing posture. It also controls the extension and retraction of the traction ropes or the position of the sliding wheel on both sides of the bionic wings to make the two bionic wings have the same wing surface curvature for stable flight, or to form different wing surface curvatures for turning, attitude correction, or airflow disturbance compensation.

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