Slidable ornithopter with bistable passive torsion double wings

Abstract

The invention discloses a gliding flapping wing aircraft with bistable passive torsion double wings, which belongs to the technical field of aircrafts, and comprises a fuselage skeleton, a left flapping wing, a right flapping wing, a bistable passive torsion mechanism, a transmission flapping mechanism, a gliding mechanism and a tail vane, bistable passive torsion mechanisms are arranged at the roots of the left flapping wing and the right flapping wing, the gliding mechanism is a deceleration claw-damping rotating wheel mechanism controlled by a steering engine, and a damping rotating wheel is fixedly connected to an output shaft of the transmission flapping mechanism. The flapping wings of the aircraft are passively twisted in the flapping process, and are switched between two steady states in a reciprocating manner, so that the average lift force of the flapping wings in a flapping period is improved, and the effective load of the aircraft is favorably improved; the elastic supporting mechanism can provide steady-state force for the flapping wings, lateral wind and turbulent flow are prevented from interfering with the steady state of the flapping wings, and the sliding function facilitates long-distance flight of the aircraft and improves the cruising ability. And the tail vane can control the yawing and pitching movement.

Description

Technical Field

[0001] The present invention belongs to the technical field of aircraft, and particularly relates to a gliding flapping-wing aircraft with bistable passive torsion double wings. Background Art

[0003] At present, most existing flapping-wing aircraft generate the lift required for flight by driving a single-segment flapping wing to flap up and down with a motor. Except for the structure of the aircraft itself and its control system, the effective mass that can be carried is very small. That is, the single-segment flapping-wing flapping method cannot provide enough lift at the same flapping frequency, and it is also very difficult for such aircraft to achieve long-distance or long-time flight.

[0004] In summary, the existing flapping-wing aircraft generally have problems that directly affect the performance of the aircraft, such as limited lift provided by the flapping of the flapping wings, resulting in a small effective load of the aircraft and insufficient endurance. Summary of the Invention

[0005] The purpose of the present invention is to solve the performance problems of most existing flapping-wing aircraft, such as limited lift provided by the flapping of the flapping wings, resulting in a small effective load of the aircraft and insufficient endurance, and to provide a gliding flapping-wing aircraft with bistable passive torsion double wings.

[0006] A gliding flapping-wing aircraft with bistable passive torsion double wings, comprising: a fuselage frame 1, left and right flapping wings 2, a bistable passive torsion mechanism 3, a transmission flapping mechanism 4, a gliding mechanism 5, and a tail rudder 6;

[0007] The transmission flapping mechanism 4 drives the flapping wing rocker arms symmetrically connected to both sides of the fuselage frame 1 to swing up and down, and the left and right flapping wings 2 flap up and down;

[0008] The bistable passive torsion mechanism 3 is arranged between the flapping wing rocker arm and the flapping wing;

[0009] The bistable passive torsion mechanism 3 includes: a passive torsion support 30, a cam-shaped turntable 31, an elastic support mechanism 32, a leading edge rod support platform 33, and two buffer limit posts 34;

[0010] The passive torsion support 30 is provided with an inner connection platform 30c inside and a main support platform 30a outside, and the inner connection platform 30c is fixedly connected to the outer end of the flapping wing rocker arm;

[0011] The cam-shaped turntable 31 is pivotally connected to the main support platform 30a, and a wing root rod fixing sleeve 31a is provided at the rear thereof, and its outer end face is fixedly connected to the leading edge rod support platform 33;

[0012] The leading edge rod support platform 33 and the wing root rod fixing sleeve 31a are respectively fixedly connected to the leading edge rod and the wing root rod of the flapping wing;

[0013] On the upper and lower sides of the rear of the passive torsion bracket 30, buffer limit posts 34 are fixedly connected, and the wing root rod fixing sleeve 31a is located between them;

[0014] The elastic support mechanism 32 includes a push rod, a steady state spring 32b, and a slide rail block. The push rod and the slide rail block are in sliding fit, and a compressed steady state spring 32b is provided between them;

[0015] A secondary support platform 30b is provided below the main support platform 30a of the passive torsion bracket 30, and the slide rail block is arranged on the secondary support platform 30b;

[0016] The end of the push rod of the elastic support mechanism 32 is in contact with the "convex end" of the cam-shaped turntable 31, providing a steady contact force between the wing root rod fixing sleeve 31a and the upper and lower buffer limit posts 34.

[0017] The slide rail block of the elastic support mechanism 32 is axially connected or fixedly connected to the secondary support platform 30b;

[0018] If they are axially connected, the end of the push rod of the elastic support mechanism 32 is axially connected to the "convex end" of the cam-shaped turntable 31;

[0019] If they are fixedly connected, the push rod of the elastic support mechanism 32 slides up and down relative to the slide rail block, the top head at the end of the push rod is in contact with the outer contour of the "convex end" of the cam-shaped turntable 31, and the axis where the push rod is located intersects with the rotation axis of the cam-shaped turntable 31 in space.

[0020] The gliding mechanism 5 includes: a gliding drive servo 50, a crank cylindrical pin steering arm 51, a damping and decelerating support member 52, a sliding sleeve 53, a gliding spring 54, and a damping runner 55;

[0021] The gliding drive servo 50 is fixedly connected to the main support plate 10 at the front of the fuselage frame 1, and its output shaft is fixedly connected to the crank cylindrical pin steering arm 51; the damping runner 55 is fixedly connected to the output shaft 45 of the transmission flapping mechanism 4;

[0022] One end of the damping and decelerating support member 52 close to the damping runner 55 is provided with a damping claw 52c, the middle sliding rod 52b of which is slidably connected to the sliding sleeve 53 fixedly connected to the main support plate 10, and the other end of the damping and decelerating support member 52 is provided with a decelerating claw redundancy ring 52a;

[0023] The gliding spring 54 is sleeved on the sliding rod 52b, one end is connected to the sliding sleeve 53, and the other end is connected to the damping claw 52c; the cylindrical pin of the crank cylindrical pin steering arm 51 is located within the decelerating claw redundancy ring 52a, and its contact and separation with the inner ring of the decelerating claw redundancy ring 52a are controlled by the gliding drive servo 50.

[0024] The described gliding spring 54 is in a compressed state; the gliding mechanism 5 is provided with a distance sensor or an angle sensor at the roots of the left flapping rocker 20b and the right flapping rocker 20a.

[0025] On the upper side of the wing root rod fixing sleeve 31a of the cam-shaped turntable 31, an energy storage elastic rope I 37a is fixedly connected, and on the lower side, an energy storage elastic rope II 37b is fixedly connected; the other ends of the energy storage elastic rope I 37a and the energy storage elastic rope II 37b are respectively fixedly connected to the upper and lower sides of the passive torsion bracket 30; when the flapping wing is at the middle position between the upper and lower buffer limit posts 34, both the energy storage elastic rope I 37a and the energy storage elastic rope II 37b are in an unstretched state.

[0026] The left and right flapping wings 2 include a right flapping wing 21 and a left flapping wing 22, and their structures are the same; the left flapping wing 22 includes a leading edge rod 22a, a wing root rod 22b, wing veins, and a wing surface skin 22e; when the flapping wing flaps, the flapping wing and the cam-shaped turntable 31 are twisted due to fluid-structure interaction. When the wing root rod fixing sleeve 31a contacts the upper buffer limit post 34, the wing surface of the flapping wing is in a horizontal steady state position, and the position where the wing root rod 22b is located is recorded as OA; when the wing root rod fixing sleeve 31a contacts the lower buffer limit post 34, the wing surface of the flapping wing is in the limit steady state position of the torsional motion, and the position where the wing root rod 22b is located is recorded as OB; ∠AOB is the torsional angle of the torsional motion of the flapping wing.

[0027] The transmission flapping mechanism 4 is driven by a drive motor 40, and the drive motor 40 is fixedly connected to the main support plate 10; the left and right crank drive arms of the transmission flapping mechanism 4 rotate symmetrically and synchronously in a circle, and respectively drive the left flapping rocker 20b and the right flapping rocker 20a to swing up and down through the left ball head pull rod 47b and the right ball head pull rod 47a, thereby realizing the symmetric and synchronous flapping of the left flapping wing 22 and the right flapping wing 21.

[0028] The tail rudder 6 includes a pitch servo 61, a yaw servo 65, and a fan-shaped tail wing 67. The pitch servo 61 and the yaw servo 65 are both arranged at the rear of the fuselage frame 1, and respectively control the lifting and lowering movement and the left and right rotation of the fan-shaped tail wing 67.

[0029] Another object of the present invention is to provide a flight and gliding method for a flapping wing aircraft;

[0030] A flight and gliding method for a flapping wing aircraft includes:

[0031] 1) The drive motor 40 is started, the left and right flapping wings 2 flap, the aircraft flies, and the gliding drive servo 50 separates the damping claw 52c of the damping and decelerating support member 52 from the damping runner 55 through the crank cylindrical pin rudder arm 51;

[0032] 2) Before gliding, the gliding drive servo 50 controls the cylindrical pin of the crank cylindrical pin rudder arm 51 to be in a separated state from the deceleration claw redundancy ring 52a of the damping deceleration support member 52. The damping claw 52c is in contact with the damping wheel sleeve 55b of the damping runner 55 under the elastic force of the gliding spring 54;

[0033] 3) During gliding, the drive motor 40 decelerates. Distance sensors or angle sensors provided at the roots of the left and right flapping rocker arms detect that the left and right flapping wings 2 reach the gliding position, and the drive motor 40 stops. The gliding drive servo 50 increases the contact force between the damping claw 52c and the damping runner 55 by controlling the cylindrical pin of the crank cylindrical pin rudder arm 51, stopping the rotation of the damping runner 55, and the aircraft glides;

[0034] 4) When releasing the gliding state, the gliding drive servo 50 drives the crank cylindrical pin rudder arm 51 to rotate outwards, separating the damping claw 52c from the damping runner 55. When the two are separated, the drive motor 40 is quickly started to resume the flapping of the double wings, and the aircraft flies.

[0035] The present invention provides a gliding flapping-wing aircraft with bistable passive torsion double wings, belonging to the technical field of aircraft. It includes: a fuselage skeleton, left and right flapping wings, a bistable passive torsion mechanism, a transmission flapping mechanism, a gliding mechanism, and a tail rudder. Among them: the transmission flapping mechanism is a motor-driven spatial crank rocker mechanism, the roots of the left and right flapping wings are provided with a bistable passive torsion mechanism, the gliding mechanism is a servo-controlled deceleration claw - damping runner mechanism, and the damping runner is fixedly connected to the output shaft of the transmission flapping mechanism. During the flapping process of the flapping wings of this aircraft, passive torsion occurs, reciprocally switching between two stable states, improving the average lift force within one flapping cycle of the flapping wings, and contributing to the improvement of the effective payload of the aircraft; the elastic support mechanism can provide a stable state force for the flapping wings, preventing lateral wind and turbulence from interfering with their stable states. The gliding function helps the aircraft fly long distances and improve its endurance; the tail rudder can control its yaw and pitch movements.

[0036] In summary, compared with the prior art, the present invention has the following beneficial effects and advantages:

[0037] A bistable passive torsion mechanism 3 is provided at the roots of the left and right flapping wings 2 of the flapping-wing aircraft of the present invention. During the up and down flapping process of the double wings, passive torsion of the left and right flapping wings 2 can be realized through fluid-structure interaction, the release of energy stored in the energy storage elastic rope, and the inertia of the mechanism movement, improving the average lift force within one flapping cycle of the flapping wings, and contributing to the improvement of the effective payload of the aircraft;

[0038] In the bistable passive torsion mechanism 3 of the present invention, the elastic support mechanism 32 provides a stable state force for the flapping wings, preventing interference from lateral wind and turbulence during the flapping or gliding process;

[0039] The flapping-wing aircraft of the present invention has a taxiing function and can perform arbitrary conversion between two flight modes of flapping and taxiing. It is equipped with a servo-controlled deceleration claw-damper pulley taxiing mechanism, which helps the aircraft fly long distances and improve endurance. Therefore, the flapping-wing aircraft of the present invention is suitable for information collection and monitoring work such as image acquisition and environmental detection. Brief Description of the Drawings

[0040] Figure 1 is a schematic diagram of the overall structure of a taxiable flapping-wing aircraft with bistable passive torsion wings according to the present invention;

[0041] Figure 2 is a three-dimensional structure schematic diagram of the fuselage skeleton of a taxiable flapping-wing aircraft with bistable passive torsion wings according to the present invention;

[0042] Figure 3 is an exploded structure schematic diagram of the front part of the fuselage skeleton of a taxiable flapping-wing aircraft with bistable passive torsion wings according to the present invention;

[0043] Figure 4 is a three-dimensional structure schematic diagram of the transmission flapping mechanism and the taxiing mechanism of a taxiable flapping-wing aircraft with bistable passive torsion wings according to the present invention;

[0044] Figure 5 is a three-dimensional structure schematic diagram of the transmission flapping mechanism of a taxiable flapping-wing aircraft with bistable passive torsion wings according to the present invention;

[0045] Figure 6 is a schematic diagram of the state of the taxiing mechanism and its specific structure when the taxiing of a taxiable flapping-wing aircraft with bistable passive torsion wings according to the present invention is released;

[0046] Figure 7 is the state of the taxiing mechanism before taxiing of a taxiable flapping-wing aircraft with bistable passive torsion wings according to the present invention;

[0047] Figure 8 is the state of the taxiing mechanism during taxiing of a taxiable flapping-wing aircraft with bistable passive torsion wings according to the present invention;

[0048] Figure 9 is a schematic diagram of the specific structure of the connection mode between the flapping wings and the bistable torsion mechanism of a taxiable flapping-wing aircraft with bistable passive torsion wings according to the present invention;

[0049] Figure 10 is a schematic diagram of the specific structure of the left flapping wing of a taxiable flapping-wing aircraft with bistable passive torsion wings according to the present invention;

[0050] Figure 11Schematic diagrams of two stable positions of the bistable passive torsion mechanism in Embodiment 1 of a gliding flapping-wing aircraft with bistable passive torsion wings according to the present invention; wherein Figure 11 (a) shows the stable position I of the bistable passive torsion mechanism in Embodiment 1, with the passive torsion angle of the flapping wing being 0° (state during the downward flapping process of the flapping wing); Figure 11 (b) shows the stable position II of the bistable passive torsion mechanism in Embodiment 1, where the flapping wing is at the limit position of the torsional movement, and the passive torsion angle of the flapping wing is the largest (state during the upward flapping process of the flapping wing);

[0051] Figure 12 Schematic diagram of the exploded structure of the bistable passive torsion mechanism in Embodiment 1 of a gliding flapping-wing aircraft with bistable passive torsion wings according to the present invention;

[0052] Figure 13 Schematic diagram of the state change of the bistable passive torsion mechanism during the flapping process of the flapping wing in Embodiment 1 of a gliding flapping-wing aircraft with bistable passive torsion wings according to the present invention; wherein Figure 13 (a) shows the stable position I of the bistable passive torsion mechanism in Embodiment 1, in the state of the downward flapping process of the flapping wing; Figure 13 (b) shows the position state of the bistable passive torsion mechanism during the transition process of the flapping wing from downward flapping to upward flapping (from upward flapping to downward flapping) in Embodiment 1; Figure 13 (c) shows the stable position II of the bistable passive torsion mechanism in Embodiment 1, in the state of the upward flapping process of the flapping wing;

[0053] Figure 14 Schematic diagrams of two stable positions of the bistable passive torsion mechanism in Embodiment 2 of a gliding flapping-wing aircraft with bistable passive torsion wings according to the present invention; wherein Figure 14 (a) shows the stable position I of the bistable passive torsion mechanism in Embodiment 2, with the passive torsion angle of the flapping wing being 0° (state during the downward flapping process of the flapping wing); Figure 14 (b) shows the stable position II of the bistable passive torsion mechanism in Embodiment 2, where the flapping wing is at the limit position of the torsional movement, and the passive torsion angle of the flapping wing is the largest (state during the upward flapping process of the flapping wing);

[0054] Figure 15 Schematic diagram of the state change of the bistable passive torsion mechanism during the flapping process of the flapping wing in Embodiment 2 of a gliding flapping-wing aircraft with bistable passive torsion wings according to the present invention; wherein Figure 15 (a) shows the stable position I of the bistable passive torsion mechanism in Embodiment 2, in the state of the downward flapping process of the flapping wing; Figure 15 (b) shows the position state of the bistable passive torsion mechanism during the transition process of the flapping wing from downward flapping to upward flapping (from upward flapping to downward flapping) in Embodiment 2; Figure 15 (c) shows the stable position II of the bistable passive torsion mechanism in Embodiment 2, in the state of the upward flapping process of the flapping wing;

[0055] Figure 16 It is a schematic structural diagram of adding an energy storage elastic rope to the bistable passive torsion mechanism in Embodiment 1 and Embodiment 2 of a gliding flapping-wing aircraft with bistable passive torsion wings according to the present invention; wherein Figure 16 (a) is the specific structural state of adding an energy storage elastic rope to the bistable passive torsion mechanism in Embodiment 1; Figure 16 (b) is the specific structural state of adding an energy storage elastic rope to the bistable passive torsion mechanism in Embodiment 2;

[0056] Figure 17 It is a three-dimensional structural diagram of the tail rudder of a gliding flapping-wing aircraft with bistable passive torsion wings according to the present invention;

[0057] Figure 18 It is an exploded structural diagram of the tail rudder of a gliding flapping-wing aircraft with bistable passive torsion wings according to the present invention;

[0058] Figure 19 It is a schematic diagram of the state of the flapping wings of a gliding flapping-wing aircraft with bistable passive torsion wings at the upper limit position;

[0059] Figure 20 It is a schematic diagram of the downward flapping state of the flapping wings of a gliding flapping-wing aircraft with bistable passive torsion wings according to the present invention;

[0060] Figure 21 It is a schematic diagram of the state of the flapping wings of a gliding flapping-wing aircraft with bistable passive torsion wings at the lower limit position;

[0061] Figure 22 It is a schematic diagram of the upward flapping state of the flapping wings of a gliding flapping-wing aircraft with bistable passive torsion wings according to the present invention;

[0062] Figure 23 It is the state A of the tail rudder when the gliding flapping-wing aircraft with bistable passive torsion wings makes a pitching motion according to the present invention;

[0063] Figure 24 It is the state B of the tail rudder when the gliding flapping-wing aircraft with bistable passive torsion wings makes a pitching motion according to the present invention;

[0064] Figure 25 It is the state of the tail rudder when the gliding flapping-wing aircraft with bistable passive torsion wings makes a yawing motion according to the present invention.

[0065] In the drawings:

[0066] 1. Airframe skeleton; 10. Main support plate; 10a. Anti-collision strip; 11. Right support plate; 12. Left support plate; 13. Connecting column; 14. Bearing; 15. Hollow connecting rod;

[0067] 2. Left and right flapping wings; 20. Flapping wing support base; 20a. Right flapping wing rocker; 20b. Left flapping wing rocker; 21. Right flapping wing; 22. Left flapping wing; 22a. Leading edge rod; 22b. Wing root rod; 22c. Connector; 22d. Wing vein rod; 22e. Wing surface skin;

[0068] 3. Bistable passive torsion mechanism; 30. Passive torsion support; 30a. Main support platform; 30b. Sub-support platform; 30c. Inner connection platform; 31. Cam-shaped turntable; 31a. Wing root rod fixing sleeve; 32. Elastic support mechanism; 32a. Elastic ejector rod; 32b. Steady state spring; 32c. Slide rail rotating block; 33. Leading edge rod support platform; 34. Buffer limit pile; 35. Centering elastic ejector rod; 35a. Top head; 36. Slide rail fixing block; 37a. Energy storage elastic rope Ⅰ; 37b. Energy storage elastic rope Ⅱ;

[0069] 4. Transmission flapping mechanism; 40. Driving motor; 41. Small gear; 42. Double-layer composite gear; 43. Output gear; 44. Transmission shaft; 45. Output shaft; 46a. Right crank drive arm; 46b. Left crank drive arm; 47a. Right ball head pull rod; 47b. Left ball head pull rod;

[0070] 5. Gliding mechanism; 50. Gliding drive servo; 51. Crank cylindrical pin rudder arm; 52. Damping deceleration support; 52a. Deceleration claw redundancy ring; 52b. Slide rod; 52c. Damping claw; 53. Slide sleeve; 54. Gliding spring; 55. Damping runner; 55a. Fixed disk; 55b. Damping wheel sleeve;

[0071] 6. Tail rudder; 60. Tail rudder support; 61. Pitch servo; 62. Pitch rudder arm; 63. Link rod; 64. Rocker support; 65. Yaw servo; 66. Yaw rudder arm; 67. Sector tail wing; 67a. Tail wing support; 67b. Tail wing support rod; 67c. Tail wing skin. Detailed implementation mode

[0072] Embodiment 1

[0073] A gliding flapping wing aircraft with bistable passive torsion double wings, comprising: fuselage skeleton 1, left and right flapping wings 2, bistable passive torsion mechanism 3, transmission flapping mechanism 4, gliding mechanism 5, tail rudder 6;

[0074] The transmission flapping mechanism 4 drives the left flapping wing rocker 20b and the right flapping wing rocker 20a symmetrically connected to both sides of the fuselage skeleton 1 to swing up and down, and the left and right flapping wings 2 flap up and down;

[0075] The bistable passive torsion mechanism 3 is arranged between the flapping wing rocker and the flapping wing;

[0076] The bistable passive torsion mechanism 3 includes: a passive torsion bracket 30, a cam-shaped turntable 31, an elastic support mechanism 32, a leading-edge support platform 33, and two buffer limit posts 34;

[0077] An inner connecting platform 30c is vertically provided inside the passive torsion bracket 30, and a main support platform 30a is vertically provided outside. The inner connecting platform 30c is fixedly connected to the outer end of the flapping rocker;

[0078] The cam-shaped turntable 31 is pivotally connected to the main support platform 30a. A wing root rod fixing sleeve 31a is provided at the rear thereof, and its outer end face is perpendicularly and fixedly connected to the leading-edge support platform 33;

[0079] The leading-edge support platform 33 and the wing root rod fixing sleeve 31a are respectively fixedly connected to the leading-edge rod of the flapping wing and the wing root rod of the flapping wing;

[0080] The buffer limit posts 34 are fixedly connected to the upper and lower ends at the rear side of the passive torsion bracket 30, and the wing root rod fixing sleeve 31a is located between them;

[0081] The elastic support mechanism 32 includes an elastic ejector rod 32a, a steady-state spring 32b, and a slide rail rotating block 32c. The elastic ejector rod 32a and the slide rail rotating block 32c are in sliding fit;

[0082] The steady-state spring 32b is sleeved on the elastic ejector rod 32a. The upper end is connected to the end of the elastic ejector rod 32a, and the lower end is connected to the upper end face of the slide rail rotating block 32c. The steady-state spring 32b is in a compressed state;

[0083] A sub-support platform 30b is provided below the main support platform 30a of the passive torsion bracket 30. The sub-support platform 30b is pivotally connected to the slide rail rotating block 32c, and the upper end of the elastic ejector rod 32a of the elastic support mechanism 32 is pivotally connected to the "convex end" of the cam-shaped turntable 31;

[0084] Therefore, the elastic support mechanism 32 provides a steady-state contact force between the wing root rod fixing sleeve 31a and the upper and lower buffer limit posts 34, that is, provides a steady-state force for the passive torsion movement during the flapping of the flapping wing, and prevents interference from lateral wind and turbulence during flight.

[0085] The gliding mechanism 5 includes: a gliding driving servo 50, a crank cylindrical pin steering arm 51, a damping and decelerating support member 52, a sliding sleeve 53, a gliding spring 54, and a damping runner 55;

[0086] The gliding driving servo 50 is fixedly connected to the main support plate 10 at the front of the fuselage frame 1, and its output shaft is fixedly connected to the crank cylindrical pin steering arm 51;

[0087] The damping runner 55 includes a fixed disk 55a and a damping wheel sleeve 55b. The fixed disk 55a is fixedly connected to the output shaft 45 of the driving flapping mechanism 4, and a damping wheel sleeve 55b is provided outside the fixed disk 55a;

[0088] One end of the damping and decelerating support member 52 close to the damping runner 55 is provided with a damping claw 52c. The middle sliding rod 52b thereof is slidably connected with a sliding sleeve 53 fixedly connected to the main support plate 10. The other end of the damping and decelerating support member 52 is provided with a decelerating claw redundancy ring 52a;

[0089] The gliding spring 54 is in a compressed state and sleeved on the sliding rod 52b. One end thereof is connected to the sliding sleeve 53, and the other end is connected to the damping claw 52c. The cylindrical pin of the crank cylindrical pin rudder arm 51 is located within the decelerating claw redundancy ring 52a, and its contact and separation with the inner ring of the decelerating claw redundancy ring 52a are controlled by the gliding drive servo 50.

[0090] The gliding mechanism 5 is provided with a distance sensor or an angle sensor at the roots of the left flapping wing rocker 20b and the right flapping wing rocker 20a.

[0091] See the appendix Figure 16 As shown in the appendix, the upper end of the wing root rod fixing sleeve 31a of the cam-shaped turntable 31 is fixedly connected with the energy storage elastic rope I 37a, and its lower end is fixedly connected with the energy storage elastic rope II 37b. The other ends of the energy storage elastic rope I 37a and the energy storage elastic rope II 37b are respectively fixedly connected with the upper and lower ends of the passive torsion bracket 30. When the elastic ejector rod 32a faces the "convex end" of the cam-shaped turntable 31, the wing root rod fixing sleeve 31a at the rear side of the cam-shaped turntable 31 is located at the position between the upper and lower two buffer limit piles 34, that is, the flapping wing is at the transition position between two steady-state positions. At this time, both the energy storage elastic rope I 37a and the energy storage elastic rope II 37b are in an un-stretched state.

[0092] The left and right flapping wings 2 include a right flapping wing 21 and a left flapping wing 22, and the right flapping wing 21 and the left flapping wing 22 have the same structure. The left flapping wing 22 is composed of a leading edge rod 22a, a wing root rod 22b, a connecting head 22c, a wing vein rod 22d and a wing surface skin 22e. The leading edge rod 22a is fixedly connected to the leading edge rod support platform 33 and is perpendicular to the outer end surface of the cam-shaped turntable 31. The wing root rod 22b is fixedly connected within the wing root rod fixing sleeve 31a at the rear end of the cam-shaped turntable 31;

[0093] The leading edge rod 22a is connected to the wing vein rod 22d through the connecting head 22c, thereby forming a flapping wing vein skeleton;

[0094] See the appendix Figure 15, when the flapping wing flaps, due to fluid-structure interaction, the flapping wing and the cam-shaped turntable 31 are torsionally deformed passively. When the fixing sleeve 31a of the wing root rod is in contact with the upper buffer limit post 34, the wing root rod 22b and the entire flapping wing surface are in a horizontal position. Denote the position of the wing root rod 22b at this time as OA; when the fixing sleeve 31a of the wing root rod is in contact with the lower buffer limit post 34, the wing root rod 22b and the entire flapping wing surface are in the lower limit position of the torsional movement. Denote the position of the wing root rod 22b at this time as OB; in summary, ∠AOB is the torsional angle of the flapping wing torsional movement;

[0095] In actual manufacturing, the leading edge rod 22a, the wing root rod 22b, and the wing vein rod 22d can adopt carbon fiber rods of different thicknesses, and the wing surface skin 22e adopts a lightweight and high-strength polyester or nylon film in actual manufacturing.

[0096] The fuselage frame 1 includes a main support plate 10, an anti-collision strip 10a, a right support plate 11, a left support plate 12, a connecting column 13, a hollow connecting rod 15, and a flapping wing support seat 20. The left support plate 12 and the right support plate 11 are symmetrically fixed to the left and right sides of the main support plate 10 through the connecting column 13, and the anti-collision strip 10a is fixed to the front part of the main support plate 10; the front end of the hollow connecting rod 15 is fixed to the rear end of the main support plate 10, and its rear end is fixedly connected to the rudder support 60 of the tail rudder 6; the flapping wing support seat 20 is fixedly connected to the upper end of the main support plate 10, and its left and right sides are symmetrically connected to the left flapping wing rocker 20b and the right flapping wing rocker 20a.

[0097] The transmission and flapping mechanism 4 includes a driving motor 40, a small gear 41, a double-layer composite gear 42, an output gear 43, a transmission shaft 44, an output shaft 45, a left crank transmission arm 46b, a right crank transmission arm 46a, a left ball joint pull rod 47b, a right ball joint pull rod 47a, a left flapping wing rocker 20b, and a right flapping wing rocker 20a;

[0098] The transmission and flapping mechanism 4 is driven by the driving motor 40, and the driving motor 40 is fixed to the rear part of the main support plate 10; the transmission shaft 44 and the output shaft 45 are sequentially axially connected to the middle and front parts of the fuselage frame 1, and bearings 14 are provided at the axially connected parts;

[0099] The double-layer composite gear 42 is fixed to the transmission shaft 44, the output gear 43 is fixed to the output shaft 45, and the small gear 41 is fixed to the output shaft of the driving motor 40;

[0100] The large-tooth-number end of the double-layer composite gear 42 meshes with the small gear 41, and its small-tooth-number end meshes with the output gear 43; on the left and right sides of the output shaft 45, a left crank drive arm 46b and a right crank drive arm 46a are symmetrically and fixedly connected. The left crank drive arm 46b and the right crank drive arm 46a rotate circumferentially symmetrically and synchronously, and drive the left flapping rocker 20b and the right flapping rocker 20a on the left and right sides to swing up and down respectively through a left ball head pull rod 47b and a right ball head pull rod 47a, thereby realizing the symmetric and synchronous flapping of the left flapping wing 22 and the right flapping wing 21, and thus constituting a transmission and flapping mechanism 4 of a spatial crank-rocker mechanism (RSSR).

[0101] The tail rudder 6 includes a tail rudder bracket 60, a pitch servo 61, a pitch rudder arm 62, a connecting rod 63, a rocker bracket 64, a yaw servo 65, a yaw rudder arm 66, and a fan-shaped tail fin 67;

[0102] The pitch servo 61 is fixedly connected to the front bracket of the tail rudder bracket 60, and its output shaft is fixedly connected to the pitch rudder arm 62, and can drive the pitch rudder arm 62 to rotate; the rocker bracket 64 is in a U shape, and is pivotally connected to the rear part of the tail rudder bracket 60 through a front-side corner, and one end of the connecting rod 63 is pivotally connected to the top of this side, and the other end of the connecting rod 63 is pivotally connected to the pitch rudder arm 62, thereby constituting a crank-rocker mechanism;

[0103] The yaw servo 65 is fixedly connected to the rear side of the rocker bracket 64, the output shaft of the yaw servo 65 is fixedly connected to the yaw rudder arm 66, the yaw rudder arm 66 is fixedly connected to the tail fin bracket 67a of the fan-shaped tail fin 67 backward, and the yaw servo 65 can drive the fan-shaped tail fin 67 to rotate around its output shaft; the fan-shaped tail fin 67 further includes a tail fin support rod 67b fixedly connected to the tail fin bracket 67a and a tail fin skin 67c wrapped outside the surface tail fin support rod 67b.

[0104] Embodiment 2

[0105] In Embodiment 2, only a partial replacement of the structure of the elastic support mechanism 32 in the bistable passive torsion mechanism 3 in Embodiment 1 is carried out, and the function of the flapping wing passive torsion bistability in the present invention can also be realized. Specifically:

[0106] See Appendix Figure 14 and Appendix Figure 15 , replace the elastic ejector rod 32a in the elastic support mechanism 32 with a centric elastic ejector rod 35, and replace the slide rail rotating block 32c with a slide rail fixed block 36; the slide rail fixed block 36 is fixedly connected to the secondary support platform 30b at the lower part of the passive torsion bracket 30, and the centric elastic ejector rod 35 slides up and down along the slide rail fixed block 36;

[0107] The upper end of the centering elastic ejector rod 35 is provided with an ejector head 35a, and the ejector head 35a is in contact with the outer contour of the "convex end" of the cam-shaped turntable 31. A steady-state spring 32b is also provided between the lower side of the ejector head 35a and the upper end surface of the slide rail fixing block 36; the steady-state spring 32b is sleeved on the centering elastic ejector rod 35 to provide the contact force between the ejector head 35a and the outer contour of the cam-shaped turntable 31 and the steady-state force of the flapping wing; the axis where the centering elastic ejector rod 35 is located intersects with the rotating shaft of the cam-shaped turntable 31 in space, that is, it is centered.

[0108] The mechanism movement process of a gliding flapping-wing aircraft with bistable passive torsion double wings in the present invention is specifically as follows:

[0109] During operation, the drive flapping mechanism 4 of a gliding flapping-wing aircraft with bistable passive torsion double wings in the present invention is driven by a drive motor 40. The output shaft of the drive motor 40 drives the small gear 41 to rotate, and the small gear 41 drives the large-tooth-number end of the double-layer composite gear 42 to rotate. Then, the small-tooth-number end of the double-layer composite gear 42 drives the output gear 43 to rotate, forming a two-stage reduction drive; the output shaft 45 rotates to drive the left crank drive arm 46b and the right crank drive arm 46a on its left and right sides to rotate symmetrically and synchronously in a circular motion. The left ball joint rod 47b and the right ball joint rod 47a drive the left flapping-wing rocker 20b and the right flapping-wing rocker 20a to swing up and down respectively. The swinging of the two will drive the bistable passive torsion mechanism 3 and the flapping wing on their outer sides to flap synchronously.

[0110] When the double wings flap, the left flapping wing 22 and the right flapping wing 21 of the flapping-wing aircraft flap symmetrically and synchronously, and bistable passive torsion mechanisms 3 are provided at the roots of both the left flapping wing 22 and the right flapping wing 21. Therefore, during the up-and-down flapping process of the left and right flapping wings 2, the bistable passive torsion mechanism 3 is driven to perform passive torsion movement through the fluid-structure interaction (the flapping wing is an asymmetric flapping wing, and the axis where the leading-edge rod of the flapping wing is located is the rotating shaft of the flapping-wing torsion movement), realizing the passive torsion movement of the flapping wing between two steady-state positions (steady-state position I, steady-state position II). Since the passive torsion movement modes of the left flapping wing 22 and the right flapping wing 21 are the same during the flapping process, taking the left flapping wing 22 and the bistable passive torsion mechanism 3 at its root as an example:

[0111] See the appendix Figure 19 , when the left flapping wing 22 is in the upper limit position, the wing root rod fixing sleeve 31a of the cam-shaped turntable 31 in the bistable passive torsion mechanism 3 is in contact with the upper buffer limit pile 34. Specifically, see the appendix Figure 11 (a) and the appendix Figure 13 (a), appendix Figure 14 (a) and the appendix Figure 15 (a). Taking this as the initial position, the left flapping wing 22 has not undergone torsion movement relative to the passive torsion bracket 30, and the torsion angle is 0°. This position is recorded as the steady-state position I, and the description starts from this position as the starting position of the flapping cycle.

[0112] See the appendix Figure 20 and the appendix Figure 21 During the flapping process of the left flapping wing 22 from the upper limit position to the lower limit position, due to the fluid-structure interaction on the lower surface of the left flapping wing 22 and the existence of the upper buffer limit post 34, the left flapping wing 22 and the bistable passive torsion mechanism 3 have always been in the steady state position I, that is, the torsion state does not occur, and positive lift is provided for the fuselage during the entire downward flapping process of the left flapping wing 22; during this process, the energy storage elastic rope I 37a has always been in an un-stretched state, and the energy storage elastic rope II 37b is in an extended and stretched energy storage state;

[0113] During the conversion process of the left flapping wing 22 from the lower limit position to the upper limit position, due to the fluid-structure interaction, the release of the energy stored in the energy storage elastic rope II 37b, and the inertia of the mechanism movement, the cam-shaped turntable 31 in the bistable passive torsion mechanism 3 rotates rapidly. Due to the action of the elastic support mechanism 32, the upper wing root rod fixing sleeve 31a on it quickly contacts the lower buffer limit post 34 and tends to be stable. For details, see the appendix Figure 11 (b) and the appendix Figure 13 (c), the appendix Figure 14 (b) and the appendix Figure 15 (c), the left flapping wing 22 undergoes passive torsion movement during this process, and the bistable passive torsion mechanism 3 twists to the steady state position II, and the torsion angle is ∠AOB; during this process, the energy storage elastic rope I 37a becomes an extended and stretched energy storage state, and the energy storage elastic rope II 37b becomes an un-stretched state;

[0114] See the appendix Figure 22 During the flapping process of the left flapping wing 22 from the lower limit position to the upper limit position, the bistable passive torsion mechanism 3 is in the steady state position II after passive torsion, reducing the resistance of the left flapping wing 22 during upward movement, and thus increasing the average lift of the left flapping wing 22 within one cycle; when the left flapping wing 22 flaps to the upper limit position, due to the fluid-structure interaction, the release of the energy stored in the energy storage elastic rope I 37a, and the inertia of the mechanism movement, the left flapping wing 22 will return to the upper limit position shown in the appendix Figure 19 That is, the steady state position I where the flapping wing and the bistable passive torsion mechanism 3 do not undergo torsion;

[0115] The movement process of the right flapping wing 21 on the right side and the bistable passive torsion mechanism 3 at its root is the same as that on the left side.

[0116] When the flapping wing aircraft of the present invention is flying, the conversion between two flight modes of flapping and gliding can be carried out through the gliding mechanism 5. The specific process is as follows:

[0117] The drive motor 40 is started, the left and right flapping wings 2 flap, and the aircraft flies. At this time, the gliding mechanism 5 is in the appendix Figure 6The state shown is that the crank pin rudder arm 51 is controlled by the gliding drive servo 50 to separate the damping claw 52c of the damping deceleration support member 52 from the damping wheel sleeve 55b of the damping rotating wheel 55;

[0118] See attached Figure 7 Before gliding, the cylindrical pin of the crank cylindrical pin rudder arm 51 and the deceleration claw redundancy ring 52a of the damping deceleration support 52 are controlled by the gliding driving servo 50 to be in a separated state, and the damping claw 52c is connected to the damping wheel sleeve 55b of the damping runner 55 by the elastic force of the gliding spring 54. At this time, the aircraft is in a pre-gliding state;

[0119] See attached Figure 8 During gliding, the distance sensor or angle sensor provided at the root of the left flapping wing rocker 20b and the right flapping wing rocker 20a is used to grasp the position of the flapping wing in real time, and the driving motor 40 is controlled to decelerate to stop, so that the left and right flapping wings 2 stop nearby. Figure 20 In the flapping stage shown in the figure, the wings are symmetrically horizontal. Due to the fluid-solid coupling and the elastic support mechanism 32, the flapping wings and the bistable passive torsion mechanism 3 are maintained in the steady-state position I, that is, no passive torsion occurs. In this process, the gliding drive servo 50 controls the cylindrical pin of the crank cylindrical pin rudder arm 51 to connect with the deceleration claw ring 52a of the damping deceleration support member 52 close to the damping rotor 55, and gradually increases the contact force between the damping claw 52c and the damping rotor 55, so as to stop the damping rotor 55 from rotating and keep the aircraft in the gliding state.

[0120] When the gliding state is released, the gliding driving servo 50 controls the cylindrical pin of the crank cylindrical pin rudder arm 51 to connect with the side of the deceleration claw redundancy ring 52a of the damping deceleration support 52 away from the damping rotating wheel 55, and further controls the damping claw 52c to separate from the damping wheel sleeve 55b of the damping rotating wheel 55. When the two are separated, the driving motor 40 is quickly started to restore the flapping state of the wings, and the gliding mechanism 5 returns to the adjacent Figure 6 In the state shown, the aircraft flaps its wings to fly.

[0121] When the flapping-wing aircraft of the present invention is flying, the pitching motion and yaw motion of the aircraft can be controlled by the tail rudder 6, and the specific process is as follows:

[0122] See attached Figure 23 and attached Figure 24 The tail rudder 6 at the rear of the aircraft controls the rotation of the rocker bracket 64 through the pitch servo 61, thereby controlling the lifting and lowering of the fan-shaped tail 67 to achieve the pitch and tilt movement of the flapping-wing aircraft of the present invention; see the attached Figure 25 By controlling the yaw servo 65 located on the rocker bracket 64 to drive the fan-shaped tail 67 to rotate, the left and right rotation of the entire fan-shaped tail 67 is controlled, thereby realizing the yaw movement of the flapping-wing aircraft of the present invention.

[0123] Through the above embodiments and the specific movement process of the mechanism, a comprehensive understanding of the overall structure of a gliding flapping-wing aircraft with bistable passive torsion double wings disclosed by the present invention can be obtained. In summary, through the attached Figure 7 , attached Figure 8 and attached Figure 6 , the working states of the gliding mechanism 5 of the flapping-wing aircraft of the present invention before gliding, during gliding, and when the gliding is released can be well demonstrated. Through the attached Figure 20 , the gliding state of the flapping-wing aircraft of the present invention can be well demonstrated. Through the attached Figures 11 - 15 , attached Figures 19 - 22 , the positions and states of the left and right flapping wings 2 of the flapping-wing aircraft of the present invention and the bistable passive torsion mechanism 3 at their roots during one flapping cycle can be well demonstrated. Through the attached Figures 23 - 25 , the working state of the tail rudder 6 of the flapping-wing aircraft of the present invention during pitching and yawing movements can be well demonstrated.

Claims

1. A gliding flapping-wing aircraft with bistable passive torsion wings, comprising: A fuselage frame (1), left and right flapping wings (2), a bistable passive torsion mechanism (3), a transmission flapping mechanism (4), a gliding mechanism (5), and a tail rudder (6); The transmission flapping mechanism (4) drives the flapping wing rockers whose symmetry axes are connected to the left and right sides of the fuselage frame (1) to swing up and down, and the left and right flapping wings (2) flap up and down; The bistable passive torsion mechanism (3) is arranged between the flapping wing rocker and the flapping wing; The bistable passive torsion mechanism (3) comprises: a passive torsion bracket (30), a cam-shaped rotating disk (31), an elastic support mechanism (32), a leading edge rod support platform (33), and two buffer limit piles (34); The passive torsion bracket (30) is provided with an inner connecting platform (30c) inside and a main supporting platform (30a) outside, and the inner connecting platform (30c) is fixedly connected to the outer end of the flapping rocker; The cam-shaped rotating disk (31) is axially connected to the main support platform (30a), and a wing root rod fixing sleeve (31a) is provided at the rear thereof, and an outer end surface thereof is fixedly connected to the leading edge rod support platform (33); The leading edge rod support platform (33) and the wing root rod fixing sleeve (31a) are respectively fixedly connected to the leading edge rod of the flapping wing and the wing root rod of the flapping wing; The passive torsion bracket (30) is fixedly connected to the upper and lower buffer limit piles (34) at the rear side, and the wing root rod fixing sleeve (31a) is located between the two. The elastic support mechanism (32) comprises a push rod, a steady-state spring (32b), and a slide rail block; the push rod and the slide rail block are slidably matched, and a steady-state spring (32b) in a compressed state is provided between the push rod and the slide rail block; A secondary support platform (30b) is provided below the main support platform (30a) of the passive torsion bracket (30), and the slide rail block is provided on the secondary support platform (30b); The end of the push rod of the elastic support mechanism (32) is connected to the "convex end" of the cam-shaped rotating disk (31), providing a steady-state contact force between the wing root rod fixing sleeve (31a) and the upper and lower buffer limit piles (34).

2. A gliding flapping-wing aircraft with bistable passive torsion wings according to claim 1, characterized in that: The slide rail block of the elastic support mechanism (32) is axially or fixedly connected to the auxiliary support platform (30b); The shaft connection is a shaft connection between the end of the push rod of the elastic support mechanism (32) and the "convex end" of the cam-shaped rotating disk (31); The fixed connection is that the push rod of the elastic support mechanism (32) slides up and down relative to the slide rail block, the top of the push rod end is connected to the outer contour of the "convex end" of the cam-shaped rotating disk (31), and the axis of the push rod intersects with the rotating axis of the cam-shaped rotating disk (31) in space.

3. A gliding flapping-wing aircraft with bistable passive torsion wings according to claim 1 or 2, characterized in that: The gliding mechanism (5) comprises: a gliding driving steering gear (50), a crank cylindrical pin rudder arm (51), a damping and decelerating support member (52), a sliding sleeve (53), a gliding spring (54), and a damping rotating wheel (55); The gliding drive servo (50) is fixedly connected to the main support plate (10) at the front of the fuselage frame (1), and its output shaft is fixedly connected to the crank cylindrical pin rudder arm (51); the damping wheel (55) is fixedly connected to the output shaft (45) of the transmission flapping mechanism (4); The damping and decelerating support member (52) is provided with a damping claw (52c) at one end close to the damping rotating wheel (55), wherein the middle sliding rod (52b) is slidably connected to a sliding sleeve (53) fixedly connected to the main supporting plate (10), and the other end of the damping and decelerating support member (52) is provided with a decelerating claw redundancy ring (52a); The gliding spring (54) is sleeved on the sliding rod (52b), one end of which is connected to the sliding sleeve (53), and the other end of which is connected to the damping claw (52c); the cylindrical pin of the crank cylindrical pin rudder arm (51) is located in the deceleration claw margin ring (52a), and its contact and separation with the inner ring of the deceleration claw margin ring (52a) are controlled by the gliding driving steering gear (50).

4. A gliding flapping-wing aircraft with bistable passive torsion wings according to claim 3, characterized in that: The gliding spring (54) is in a compressed state; the gliding mechanism (5) is provided with a distance sensor or an angle sensor at the root of the left flapping-wing rocker (20b) and the right flapping-wing rocker (20a).

5. A gliding flapping-wing aircraft with bistable passive torsion wings according to claim 4, characterized in that: The wing root rod fixing sleeve (31a) of the cam-shaped rotating disk (31) is fixedly connected to an energy storage elastic rope I (37a) on the upper side and to an energy storage elastic rope II (37b) on the lower side; the other ends of the energy storage elastic rope I (37a) and the energy storage elastic rope II (37b) are respectively fixedly connected to the upper and lower sides of the passive torsion bracket (30); when the flapping wing is in the middle position of the upper and lower buffer limit piles (34), the energy storage elastic rope I (37a) and the energy storage elastic rope II (37b) are both in an unstretched state.

6. A gliding flapping-wing aircraft with bistable passive torsion wings according to claim 5, characterized in that: The left and right flapping wings (2) comprise a right flapping wing (21) and a left flapping wing (22), and the two have the same structure; the left flapping wing (22) comprises a leading edge rod (22a), a wing root rod (22b), wing veins and a wing surface skin (22e); when the flapping wing is flapping, the flapping wing and the cam-shaped turntable (31) are twisted due to fluid-solid coupling; when the wing root rod fixing sleeve (31a) is connected to the upper buffer limit pile (34), the flapping wing wing surface is in a horizontal steady state position, and the position of the wing root rod (22b) is recorded as OA; when the wing root rod fixing sleeve (31a) is connected to the lower buffer limit pile (34), the flapping wing wing surface is in an extreme steady state position of torsional motion, and the position of the wing root rod (22b) is recorded as OB; ∠AOB is the torsional angle of the flapping wing torsional motion.

7. A gliding flapping-wing aircraft with bistable passive torsion wings according to claim 6, characterized in that: The transmission flapping mechanism (4) is driven by a drive motor (40), and the drive motor (40) is fixedly connected to the main support plate (10); the left and right crank transmission arms of the transmission flapping mechanism (4) rotate symmetrically and synchronously in a circle, and respectively drive the left flapping wing rocker (20b) and the right flapping wing rocker (20a) to swing up and down through the left ball head pull rod (47b) and the right ball head pull rod (47a), thereby achieving symmetrical and synchronous flapping of the left flapping wing (22) and the right flapping wing (21).

8. A gliding flapping-wing aircraft with bistable passive torsion wings according to claim 6 or 7, characterized in that: The tail rudder (6) comprises a pitch servo (61), a yaw servo (65) and a fan-shaped tail wing (67). The pitch servo (61) and the yaw servo (65) are both arranged at the rear of the fuselage frame (1), and the two respectively control the lifting and lowering movement and left and right rotation of the fan-shaped tail wing (67).

9. A method for gliding a flapping-wing aircraft, characterized in that: A gliding flapping-wing aircraft with bistable passive torsion wings as described in claim 4; 1) The driving motor (40) is started, the left and right flapping wings (2) flap, the aircraft flies, and the gliding driving servo (50) separates the damping claw (52c) of the damping deceleration support member (52) from the damping rotating wheel (55) through the crank cylindrical pin rudder arm (51); 2) before gliding, the gliding driving servo (50) controls the cylindrical pin of the crank cylindrical pin rudder arm (51) and the deceleration claw margin ring (52a) of the damping deceleration support member (52) to be in a separated state, and the damping claw (52c) is connected to the damping wheel sleeve (55b) of the damping rotating wheel (55) under the elastic force of the gliding spring (54); 3) During gliding, the drive motor (40) decelerates, and the distance sensors or angle sensors provided at the roots of the left and right flapping wing rockers detect that the left and right flapping wings (2) have reached the gliding position, and the drive motor (40) stops; the gliding drive servo (50) increases the contact force between the damping claw (52c) and the damping wheel (55) by controlling the cylindrical pin of the crank cylindrical pin rudder arm (51), thereby stopping the damping wheel (55) from rotating, and the aircraft glides; 4) When the gliding is released, the crank pin rudder arm (51) is driven to rotate outwards by the gliding driving servo (50), so that the damping claw (52c) and the damping rotating wheel (55) are separated; when the two are separated, the driving motor (40) is quickly started to restore the flapping of the wings, and the aircraft takes flight.

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