Multi-degree of freedom tail for flapping wing aircraft

Abstract

The application discloses a multi-degree-of-freedom tail wing for a flapping-wing aircraft, which comprises a body frame, a yaw-elevation rudder machine, a yaw-elevation rudder arm, a central caudal bone imitating piece, a roll rudder machine, a terminal caudal bone imitating piece, a tail feather folding and unfolding rudder machine, a tail feather folding and unfolding rudder arm and tail feathers; wherein the yaw-elevation rudder machine is installed on the body frame and connected with the tail wing as a whole through a yaw-elevation connecting rod; the roll rudder machine is installed on the central caudal bone imitating piece and drives the torsion of the tail wing surface by adding a circular rudder arm and cooperating with a roll connecting piece; the tail feather folding and unfolding rudder machine is installed on the terminal caudal bone imitating piece and drives the outward unfolding or inward folding of the tail feathers at the outer sides of both ends through a tail feather folding and unfolding connecting rod, and drives the movement of the remaining tail feathers except the central tail feather through a tail feather linkage. The application can not only adjust and control the longitudinal, lateral and heading movements of the body, but also adapt the folding and unfolding of the tail feathers to the requirements of the aircraft on different maneuverability.

Description

Technical Field

[0001] This invention relates to the field of biomimetic aircraft technology, and in particular to a multi-degree-of-freedom tail fin for flapping-wing aircraft. Background Technology

[0002] Flapping-wing Aerial Vehicles (FWAVs) are a new type of biomimetic flying robot, which can be specifically divided into bird-inspired, bat-inspired, and insect-inspired flapping-wing robots. Compared with fixed-wing and multi-rotor aircraft of the same size, flapping-wing aircraft have advantages such as better aerodynamic performance, stronger maneuverability, higher flight efficiency, and easier biomimetic stealth capabilities, and have broad application prospects in both civilian and military fields.

[0003] Among the three types of flapping-wing aircraft mentioned above, the bird-inspired flapping-wing robot has the most diverse attitude adjustment and stabilization control mechanisms, thus enabling it to perform more complex maneuvers. Specifically, in addition to wing differential motion, tail fin movement also plays a crucial role. Currently, the tail fin designs of bird-inspired flapping-wing aircraft can be broadly categorized into three types: 1. Inverted T-tails similar to those of fixed-wing aircraft; 2. V-tails with independent up-and-down deflection at both ends; 3. Feather-shaped tail fins capable of wing surface roll and deflection. However, existing designs still have some drawbacks, such as: limited tail fin degrees of freedom, resulting in insufficient torque generation under certain maneuvers, thus hindering effective attitude adjustment; and a constant tail fin area, limiting adaptability to different flight speeds.

[0004] Real bird flight is quite complex. Due to the high degree of freedom of wing movement, birds can still perform most flight maneuvers even with their tail feathers clipped. Limited by materials and mechanical mechanisms, current bird-inspired flapping-wing aircraft are insufficient to achieve the flexible movements of real bird wings. Therefore, designing a highly biomimetic tail fin has become an important issue in the field of bird-inspired flapping-wing robots. Summary of the Invention

[0005] The purpose of this invention is to address the problem that existing flapping-wing aircraft have poor maneuverability and cannot exhibit the diverse flight patterns of real birds, by providing a multi-degree-of-freedom tail fin for flapping-wing aircraft. This invention can effectively adjust the attitude of flapping-wing aircraft, enhance its stability in all directions, and endow it with the ability to adapt to different flight conditions.

[0006] The objective of this invention is achieved through the following technical solution: a multi-degree-of-freedom tail fin for a flapping-wing aircraft, comprising:

[0007] Airframe;

[0008] The yaw and pitch servo is mounted on the fuselage frame via a servo mounting bracket.

[0009] Yaw and pitch control arm, one end of which is mounted on the yaw and pitch servo, and the other end of which is connected to a yaw and pitch linkage.

[0010] The central tailbone component is connected to the tail fin frame connector via a cross shaft. The tail fin frame connector is fastened to the fuselage frame with screws. The central tailbone component is provided with an assembly slot. The yaw and pitch linkage is connected to the central tailbone component.

[0011] A roller servo is installed in the mounting slot. The roller servo is provided with an output shaft, which is connected to one end of a circular servo arm. The other end of the circular servo arm is connected to a rolling connector.

[0012] The tailbone-like end piece is engaged with the rolling connector via a pin, and the tail feather fastening cap is mounted on the tailbone-like end piece via the pin.

[0013] The tail feather retraction servo is mounted on the tailbone-like component at the end.

[0014] A tail feather retraction control arm, one end of which is connected to the tail feather retraction servo, and the other end of which is connected to a tail feather retraction linkage; and

[0015] Tail feathers are mounted on the end-shaped tailbone component, and the tail feather extension / retraction linkage is mounted on the outermost tail feather.

[0016] Optionally, the yaw and pitch servo includes a first yaw and pitch servo and a second yaw and pitch servo, the yaw and pitch servo arm includes a first yaw and pitch servo arm and a second yaw and pitch servo arm, the servo mounting component includes a first servo mounting component and a second servo mounting component, and the yaw and pitch linkage includes a first yaw and pitch linkage and a second yaw and pitch linkage.

[0017] The first yaw and pitch servo is mounted on the fuselage frame via a first servo mounting bracket, and the second yaw and pitch servo is mounted on the fuselage frame via a second servo mounting bracket;

[0018] One end of the first yaw pitch control arm is mounted on the first yaw pitch servo, and the other end is connected to the first yaw pitch linkage.

[0019] One end of the second yaw and pitch control arm is mounted on the second yaw and pitch control servo, and the other end is connected to the second yaw and pitch linkage.

[0020] The first yaw pitch link and the second yaw pitch link are respectively installed on both sides of the central tailbone component.

[0021] Optionally, the end-end pseudo-tailbone component is provided with a fixed tail feather mounting hole and multiple tail feather mounting seats. The multiple tail feather mounting seats are symmetrically arranged on both sides of the fixed tail feather mounting hole. The tail feather mounting seats are connected to the end-end pseudo-tailbone component by means of pin connection. The tail feather mounting seats are provided with retractable tail feather mounting holes, and the front ends of the two outermost tail feather mounting seats are provided with perforated arms for connecting with the tail feather retraction and extension linkage.

[0022] Optionally, the positions of the retractable tail feather mounting holes have a height difference, and the height of the retractable tail feather mounting holes gradually decreases from the fixed tail feather mounting hole in the middle to both sides, and the height change characteristics are symmetrical on both sides; the fixed tail feather mounting hole has the highest height.

[0023] Optionally, the tailbone-like component at the end is symmetrically provided with limiters for restricting the retraction and extension of the tail feathers, and the two innermost tail feather mounting seats are provided with limiters for restricting the retraction and extension of the tail feathers.

[0024] Optionally, the tail feather retraction servo includes a first tail feather retraction servo and a second tail feather retraction servo, the tail feather retraction servo arm includes a first tail feather retraction servo arm and a second tail feather retraction servo arm, and the tail feather retraction link includes a first tail feather retraction link and a second tail feather retraction link.

[0025] The first tail feather retraction servo and the second tail feather retraction servo are respectively installed on both sides of the tailbone-like component at the end;

[0026] One end of the first tail feather retraction / extension rudder arm is connected to the first tail feather retraction / extension servo, and the other end is connected to the first tail feather retraction / extension linkage.

[0027] One end of the second tail feather retraction / extension rudder arm is connected to the second tail feather retraction / extension servo, and the other end is connected to the second tail feather retraction / extension linkage.

[0028] Optionally, the tail feathers use carbon fiber tubes as a skeleton, and nylon tape and nylon cloth are used to bond the feather parts together, with the skeleton and the feather parts connected by adhesive.

[0029] Optionally, a tail feather retraction linkage is installed on the frame, and the tail feather retraction linkage is connected to the frame through an assembly hole provided thereon. The tail feather retraction linkage is made of soft rubber.

[0030] Optionally, the tail feathers include a central fixed tail feather and a plurality of retractable tail feathers symmetrically arranged on both sides of the central fixed tail feather. The central fixed tail feather is installed in the fixed tail feather mounting hole, and the plurality of retractable tail feathers are installed one-to-one in the retractable tail feather mounting hole.

[0031] Optionally, the number of retractable tail feathers is eight; the number of tail feather mounting seats is eight.

[0032] The beneficial effects of this invention are that it has more degrees of freedom of movement, and due to the large tail feather area, it can effectively adjust the roll, yaw, and pitch attitude of the flapping-wing aircraft, while also effectively enhancing the lateral, directional, and longitudinal stability of the flapping-wing aircraft. This invention uses multiple independent tail feathers instead of a thin membrane to form the tail fin surface. The tail feathers other than the central tail feather can be retracted and extended under the drive of an electric motor, which is closer to the physiological characteristics of real birds and has stronger biomimetic characteristics. Before and after the tail feathers are retracted and extended, the tail fin area changes significantly, and the corresponding aerodynamic characteristics change, which enables the flapping-wing aircraft to complete various flight modes and perform large-amplitude maneuvers. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the overall structure of the multi-degree-of-freedom tail fin of an flapping-wing aircraft;

[0034] Figure 2 This is a schematic diagram of the upper and lower oblique structures of the multi-degree-of-freedom tail fin of an flapping-wing aircraft;

[0035] Figure 3 This is a top-view structural diagram of the multi-degree-of-freedom tail fin of an ornithopter;

[0036] Figure 4 This is a schematic diagram of the roll drive structure of the multi-degree-of-freedom tail fin of an flapping-wing aircraft;

[0037] Figure 5 This is a schematic diagram of the tail feather support installation structure of a multi-degree-of-freedom tail fin of an flapping-wing aircraft.

[0038] Figure 6 This is a top-view schematic diagram of the tail feather structure of a multi-degree-of-freedom tail fin of an ornithopter;

[0039] Figure 7 This is a front view schematic diagram of the tail feather structure of a multi-degree-of-freedom tail fin of an ornithopter;

[0040] Figure 8 This is a schematic diagram of the tail feather arrangement of a multi-degree-of-freedom tail fin of an ornithopter.

[0041] In the diagram: 1. Fuselage frame; 2. First yaw / pitch servo; 3. First yaw / pitch servo arm; 4. First yaw / pitch linkage; 5. Second yaw / pitch servo; 6. Second yaw / pitch servo arm; 7. Second servo fixed component; 8. Second yaw / pitch linkage; 9. Tail frame connector; 10. Cross shaft; 11. Central tailbone component; 12. Roll servo; 13. Circular servo arm; 14. Roll connector; 15. Terminal tailbone component; 16. First tail feather retraction servo; 17. Second tail feather retraction servo; 18. First tail feather retraction servo arm; 19. Second tail feather retraction servo arm; 20. First tail feather retraction linkage; 21. Second tail feather retraction linkage. 22. Rod, 23. Tail feather fastening cover, 24. First tail feather mounting seat, 25. Second tail feather mounting seat, 26. Third tail feather mounting seat, 27. Fourth tail feather mounting seat, 28. Fifth tail feather mounting seat, 29. Sixth tail feather mounting seat, 30. Seventh tail feather mounting seat, 31. Eighth tail feather mounting seat, 32. First tail feather retraction linkage, 33. Second tail feather retraction linkage, 34. First retractable tail feather, 35. Second retractable tail feather, 36. Third retractable tail feather, 37. Fourth retractable tail feather, 38. Central fixed tail feather, 39. Fifth retractable tail feather, 40. Sixth retractable tail feather, 41. Seventh retractable tail feather, 42. Eighth retractable tail feather. Detailed Implementation

[0042] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Rather, they are merely examples of apparatuses and methods consistent with some aspects of the invention as detailed in the appended claims.

[0043] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular forms “a,” “the,” and “the” used in this invention and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0044] It should be understood that although the terms first, second, third, etc., may be used in this invention to describe various information, this information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, first information may also be referred to as second information without departing from the scope of this invention, and similarly, second information may also be referred to as first information. Depending on the context, the word "if" as used herein may be interpreted as "when," "when," or "in response to a determination."

[0045] The present invention will now be described in detail with reference to the accompanying drawings. Unless otherwise specified, the features of the following embodiments and implementations can be combined with each other.

[0046] See Figures 1-3 The present invention relates to a multi-degree-of-freedom tail for an flapping-wing aircraft, the tail comprising a frame 1, a yaw and pitch servo, a yaw and pitch control arm, a central tailbone component 12, a roller servo 13, a terminal tailbone component 16, a tail feather retraction servo, a tail feather retraction control arm, and tail feathers.

[0047] In this embodiment, the yaw and pitch servo is mounted on the fuselage frame 1 via a servo mounting bracket. The yaw and pitch servo is used to control the yaw and pitch control arm. One end of the yaw and pitch control arm is mounted on the yaw and pitch servo, and the other end of the yaw and pitch control arm is connected to a yaw and pitch linkage.

[0048] Furthermore, the yaw and pitch servo includes a first yaw and pitch servo 2 and a second yaw and pitch servo 6, the yaw and pitch control arm includes a first yaw and pitch control arm 3 and a second yaw and pitch control arm 7, the servo mounting component includes a first servo mounting component 4 and a second servo mounting component 8, and the yaw and pitch linkage includes a first yaw and pitch linkage 5 and a second yaw and pitch linkage 9. The first yaw and pitch servo 2 is mounted on the fuselage frame 1 via the first servo mounting component 4, and the second yaw and pitch servo 6 is mounted on the fuselage frame 1 via the second servo mounting component 8; one end of the first yaw and pitch control arm 3 is mounted on the first yaw and pitch servo 2, and the other end is connected to the first yaw and pitch linkage 5; one end of the second yaw and pitch control arm 7 is mounted on the second yaw and pitch servo 6, and the other end is connected to the second yaw and pitch linkage 9.

[0049] In this embodiment, the central tailbone component 12 is connected to the tail fin frame connector 10 via a cross shaft 11. The tail fin frame connector 10 is fastened to the fuselage frame 1 with screws. Figure 4 As shown. In addition, the central tailbone component 12 is also provided with a mounting slot for mounting the roll servo 13.

[0050] In this embodiment, one end of the yaw-pitch linkage is mounted on the yaw-pitch rudder arm, and the other end is connected to the central tailbone component 12. Furthermore, the first yaw-pitch linkage 5 and the second yaw-pitch linkage 9 are respectively mounted on both sides of the central tailbone component 12. It is easy to understand that the first yaw-pitch servo 2 and the second yaw-pitch servo 6 are integrally connected to the tail fin via the first yaw-pitch linkage 5 and the second yaw-pitch linkage 9.

[0051] In this embodiment, the roller servo 13 is installed in a pre-set mounting slot in the central tailbone component 12. For example... Figure 5As shown, the roller servo 13 is equipped with an output shaft, which is connected to one end of a circular servo arm 14. The other end of the circular servo arm 14 is connected to a roller connector 15, which engages with the tailbone-like component 16 via a pin. The roller servo 13 drives the rotation of the tail fin surface through the added circular servo arm 14 and the roller connector 15.

[0052] See Figures 6-7 The tailbone-like component 16 at the end is provided with a fixing hole for the tail feathers; the tailbone-like component 16 at the end is provided with multiple tail feather mounting seats, which are connected to the tailbone-like component 16 by means of pins, and the tail feather mounting seats are provided with retractable tail feather mounting holes; the tailbone-like component 16 at the end is fitted with a tail feather fastening cover 23 by a pin. It should be understood that there is a one-to-one correspondence between the tail feather mounting seats and the retractable tail feather mounting holes, and the number of tail feather mounting seats is equal to the number of retractable tail feather mounting holes.

[0053] Furthermore, multiple tail feather mounting seats are symmetrically arranged on both sides of the fixed tail feather mounting hole provided on the end imitation tailbone component 16, and the front end of the two outermost tail feather mounting seats is provided with a perforated arm, which is used to connect with the tail feather extension and retraction linkage.

[0054] Furthermore, the retractable tail feather mounting holes on the tail feather mounting base have sequentially varying heights, effectively preventing the tail feathers from colliding with each other when retracted. The fixed tail feather mounting hole has the highest height, and the height of the retractable tail feather mounting holes gradually decreases from the fixed tail feather mounting hole in the middle towards both sides, with the height change characteristic being symmetrical on both sides. Figure 6 and Figure 7 As shown, this helps to prevent the tail feathers from colliding with each other when folded.

[0055] Furthermore, in order to better limit the retraction and extension range of the tail feathers, the tailbone-like component 16 at the end is symmetrically provided with limiters for limiting the retraction and extension of the tail feathers, and the two innermost tail feather mounting seats are provided with limiters for limiting the retraction and extension of the tail feathers, which are used to constrain the lower limit of folding.

[0056] In this embodiment, the tail feather retraction servo is mounted on the tailbone-like component 16 at the end, which can control the retraction of the tail feathers (i.e., retraction outward or inward); the tail feather retraction servo arm can also control the retraction of the tail feathers, with one end connected to the tail feather retraction servo and the other end connected to the tail feather retraction linkage.

[0057] Furthermore, the tail feather retraction servo includes a first tail feather retraction servo 17 and a second tail feather retraction servo 18, the tail feather retraction servo arm includes a first tail feather retraction servo arm 19 and a second tail feather retraction servo arm 20, and the tail feather retraction linkage includes a first tail feather retraction linkage 21 and a second tail feather retraction linkage 22. The first tail feather retraction servo 17 and the second tail feather retraction servo 18 are respectively mounted on both sides of the end-capillary tailbone component 16; one end of the first tail feather retraction servo arm 19 is connected to the first tail feather retraction servo 17, and the other end is connected to the first tail feather retraction linkage 21; one end of the second tail feather retraction servo arm 20 is connected to the second tail feather retraction servo 18, and the other end is connected to the second tail feather retraction linkage 22.

[0058] In this embodiment, the tail feathers are mounted on the distal coccyx-like component 16, and the tail feather extension / retraction linkage is mounted on the outermost tail feather. See also Figures 6-8 The tail feathers have a rigid, long, flat structure. Each tail feather uses a carbon fiber tube as its skeleton, and nylon tape and nylon fabric are used to bond the feather parts together. The skeleton and feather parts are connected by adhesive. The tail feathers are designed to mimic the shape of real bird tail feathers, which gives the flapping-wing aircraft enhanced biomimetic stealth capabilities after being equipped with the tail fins in this embodiment.

[0059] The end of the skeleton is connected to the corresponding fixed tail feather mounting hole and the retractable tail feather mounting hole, so that the tail feather can be mounted on the end imitation tailbone part 16.

[0060] Furthermore, a tail feather retraction and extension linkage is installed on the frame. This linkage connects directly to the frame through mounting holes. The movement of all tail feathers except the central tail feather is driven by this linkage. Figure 8 As shown, a portion of the skeleton extends beyond the tail feathers, and the tail feather extension / retraction linkage is directly assembled onto the skeleton from which the tail feathers extend.

[0061] Furthermore, the tail feather retraction linkage includes a first tail feather retraction linkage 32 and a second tail feather retraction linkage 33, which are used to control the movement of the tail feathers on both sides.

[0062] Optionally, the tail feather extension and retraction linkage is made of soft rubber, which has a certain degree of elasticity, ensuring that each tail feather can be extended to its maximum extent.

[0063] In this embodiment, the tail feathers include a central fixed tail feather 38 and a plurality of retractable tail feathers symmetrically arranged on both sides of the central fixed tail feather 38. The central fixed tail feather 38 is installed in the fixed tail feather mounting hole provided in the tail feather mounting member 16 at the end, and the retractable tail feathers are installed one by one in the retractable tail feather mounting holes provided in the tail feather mounting base.

[0064] It should be understood that the number of tail feather mounting bases, retractable tail feather mounting holes, and retractable tail feathers are equal.

[0065] Optionally, the number of retractable tail feathers is even, and they are symmetrically arranged on both sides of the central fixed tail feather 38.

[0066] For example, such as Figure 3 As shown, in this embodiment, there are eight retractable tail feathers: the first retractable tail feather 34, the second retractable tail feather 35, the third retractable tail feather 36, the fourth retractable tail feather 37, the fifth retractable tail feather 39, the sixth retractable tail feather 40, the seventh retractable tail feather 41, and the eighth retractable tail feather 42. These eight retractable tail feathers are symmetrically arranged on both sides of the central fixed tail feather 38, that is: the first retractable tail feather 34 and the eighth retractable tail feather 42 are symmetrical, the second retractable tail feather 35 and the seventh retractable tail feather 41 are symmetrical, the third retractable tail feather 36 and the sixth retractable tail feather 40 are symmetrical, and the fourth retractable tail feather 37 and the fifth retractable tail feather 39 are symmetrical. Correspondingly, the tailbone-like component 16 at the end is symmetrically provided with eight limiters for restricting the retraction and extension of the tail feathers. Using the same sorting method as the retractable tail feathers, the eight limiters are, in order, the first limiter, the second limiter, the third limiter, the fourth limiter, the fifth limiter, the sixth limiter, the seventh limiter, and the eighth limiter. Among them, the first limiter and the eighth limiter are symmetrical, the second limiter and the seventh limiter are symmetrical, the third limiter and the sixth limiter are symmetrical, and the fourth limiter and the fifth limiter are symmetrical.

[0067] Specifically, the first and second limiters restrict the retraction and extension of the first retractable tail feather 34; the second and third limiters restrict the retraction and extension of the second retractable tail feather 35; the third and fourth limiters restrict the retraction and extension of the third retractable tail feather 36; and a separate limiter is provided on the tail feather mounting base (i.e., the innermost tail feather mounting base) corresponding to the fourth retractable tail feather 37 to constrain the lower limit of folding, while its upper limit of extension is constrained by the fourth limiter. Similarly, the eighth and seventh limiters restrict the retraction and extension of the eighth retractable tail feather 42; the seventh and sixth limiters restrict the retraction and extension of the seventh retractable tail feather 41; the sixth and fifth limiters restrict the retraction and extension of the sixth retractable tail feather 40; and a separate limiter is provided on the tail feather mounting base (i.e., the innermost tail feather mounting base) corresponding to the fifth retractable tail feather 39 to constrain the lower limit of folding, while its upper limit of extension is constrained by the fifth limiter.

[0068] For example, see Figures 6-8In this embodiment, there are eight retractable tail feathers, so there are also eight tail feather mounting bases and eight retractable tail feather mounting holes. The eight tail feather mounting seats are the first tail feather mounting seat 24, the second tail feather mounting seat 25, the third tail feather mounting seat 26, the fourth tail feather mounting seat 27, the fifth tail feather mounting seat 28, the sixth tail feather mounting seat 29, the seventh tail feather mounting seat 30, and the eighth tail feather mounting seat 31. The first retractable tail feather 34 is mounted on the first tail feather mounting seat 24, the second retractable tail feather 35 is mounted on the second tail feather mounting seat 25, the third retractable tail feather 36 is mounted on the third tail feather mounting seat 26, the fourth retractable tail feather 37 is mounted on the fourth tail feather mounting seat 27, the fifth retractable tail feather 39 is mounted on the fifth tail feather mounting seat 28, the sixth retractable tail feather 40 is mounted on the sixth tail feather mounting seat 29, the seventh retractable tail feather 41 is mounted on the seventh tail feather mounting seat 30, and the eighth retractable tail feather 42 is mounted on the eighth tail feather mounting seat 31.

[0069] It should be understood that the number of retractable tail feathers can be six or ten, depending on the actual situation. Preferably, the number of retractable tail feathers is eight. With this setting, the multi-degree-of-freedom tail fin has a better and more moderate weight and balance.

[0070] Furthermore, the first tail feather retraction link 21 and the second tail feather retraction link 22 are respectively installed on the outermost tail feathers at both ends, that is, the first tail feather retraction link 21 is installed on the first retractable tail feather 34, and the second tail feather retraction link 22 is installed on the eighth retractable tail feather 42; by pulling the first tail feather retraction link 21 and the second tail feather retraction link 22, the first retractable tail feather 34 and the eighth retractable tail feather 42 can be driven to extend outward or retract inward.

[0071] Furthermore, when the first retractable tail feather 34 and the eighth retractable tail feather 42 are driven by the first tail feather retraction servo 17 and the second tail feather retraction servo 18 to unfold outward or fold inward, the second retractable tail feather 35, the third retractable tail feather 36 and the fourth retractable tail feather 37 are driven by the first tail feather retraction linkage 32, and the fifth retractable tail feather 39, the sixth retractable tail feather 40 and the seventh retractable tail feather 41 are driven by the second tail feather retraction linkage 33.

[0072] In this embodiment, the tail fin surface, which is composed of a central fixed tail feather 38 and multiple retractable tail feathers, has a significant change in area before and after retraction. The corresponding change in aerodynamic characteristics enables the flapping-wing aircraft to complete various flight modes and perform large-scale maneuvers.

[0073] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A multi-degree-of-freedom tail fin for an ornithopter, characterized in that, include: Frame (1); The yaw and pitch servo is mounted on the fuselage frame (1) via a servo mounting bracket; Yaw and pitch control arm, one end of which is mounted on the yaw and pitch servo, and the other end of which is connected to a yaw and pitch linkage. The central tailbone component (12) is connected to the tail fin frame connector (10) via a cross shaft (11). The tail fin frame connector (10) is fastened to the fuselage frame (1) by screws. The central tailbone component (12) is provided with an assembly slot. The yaw and pitch linkage is connected to the central tailbone component (12). A roller servo (13) is installed in the mounting slot. The roller servo (13) is provided with an output shaft. The output shaft is connected to one end of a circular servo arm (14). The other end of the circular servo arm (14) is connected to a rolling connector (15). The tailbone-like component (16) at the end is engaged with the rolling connector (15) by means of a pin, and the tail feather fastening cap (23) at the end is assembled with the tail feather fastening cap (23) by means of a pin. Tail feather retraction servo is mounted on the tail bone-like component (16) at the end; Tail feather retraction control arm, one end of which is connected to the tail feather retraction servo, and the other end of which is connected to a tail feather retraction linkage. and Tail feathers are mounted on the end-shaped tailbone component (16), and the tail feather extension / retraction linkage is mounted on the outermost tail feathers.

2. The multi-degree-of-freedom tail fin for an ornithopter according to claim 1, characterized in that, The yaw and pitch servo includes a first yaw and pitch servo (2) and a second yaw and pitch servo (6), the yaw and pitch servo arm includes a first yaw and pitch servo arm (3) and a second yaw and pitch servo arm (7), the servo mounting component includes a first servo mounting component (4) and a second servo mounting component (8), and the yaw and pitch linkage includes a first yaw and pitch linkage (5) and a second yaw and pitch linkage (9). The first yaw and pitch servo (2) is mounted on the fuselage frame (1) via the first servo mounting component (4), and the second yaw and pitch servo (6) is mounted on the fuselage frame (1) via the second servo mounting component (8); One end of the first yaw pitch control arm (3) is mounted on the first yaw pitch control servo (2), and the other end is connected to the first yaw pitch linkage (5); One end of the second yaw and pitch control arm (7) is mounted on the second yaw and pitch control servo (6), and the other end is connected to the second yaw and pitch linkage (9); The first yaw pitch link (5) and the second yaw pitch link (9) are respectively installed on both sides of the central tailbone component (12).

3. The multi-degree-of-freedom tail fin for an flapping-wing aircraft according to claim 1, characterized in that, The end-end pseudo-tailbone component (16) is provided with a fixed tail feather mounting hole and multiple tail feather mounting seats. The multiple tail feather mounting seats are symmetrically arranged on both sides of the fixed tail feather mounting hole. The tail feather mounting seats are connected to the end-end pseudo-tailbone component (16) by means of pin connection. The tail feather mounting seats are provided with retractable tail feather mounting holes, and the front ends of the two outermost tail feather mounting seats are provided with perforated arms for connecting with the tail feather retraction and extension linkage.

4. The multi-degree-of-freedom tail fin for an flapping-wing aircraft according to claim 3, characterized in that, The positions of the retractable tail feather mounting holes have a height difference, and the height of the retractable tail feather mounting holes gradually decreases from the fixed tail feather mounting hole in the middle to both sides, and the height change characteristics are symmetrical on both sides; the fixed tail feather mounting hole has the highest height.

5. The multi-degree-of-freedom tail fin for an flapping-wing aircraft according to claim 3, characterized in that, The tailbone-like component (16) at the end is symmetrically provided with limiters for restricting the retraction and extension of the tail feathers, and the two tail feather mounting seats at the innermost end are provided with limiters for restricting the retraction and extension of the tail feathers.

6. The multi-degree-of-freedom tail fin for an flapping-wing aircraft according to claim 1, characterized in that, The tail feather retraction servo includes a first tail feather retraction servo (17) and a second tail feather retraction servo (18), the tail feather retraction servo arm includes a first tail feather retraction servo arm (19) and a second tail feather retraction servo arm (20), and the tail feather retraction link includes a first tail feather retraction link (21) and a second tail feather retraction link (22). The first tail feather retraction servo (17) and the second tail feather retraction servo (18) are respectively installed on both sides of the tailbone-like component (16) at the end; One end of the first tail feather retraction rudder arm (19) is connected to the first tail feather retraction servo (17), and the other end is connected to the first tail feather retraction linkage (21). One end of the second tail feather retraction rudder arm (20) is connected to the second tail feather retraction servo (18), and the other end is connected to the second tail feather retraction linkage (22).

7. The multi-degree-of-freedom tail fin for an flapping-wing aircraft according to claim 1, characterized in that, The tail feathers use carbon fiber tubes as the skeleton, and nylon tape and nylon cloth are used to bond the feather parts together. The skeleton and the feather parts are connected by adhesive.

8. The multi-degree-of-freedom tail fin for an flapping-wing aircraft according to claim 7, characterized in that, The frame is equipped with a tail feather retraction linkage component, which is connected to the frame through mounting holes. The tail feather retraction linkage component is made of soft rubber.

9. The multi-degree-of-freedom tail fin for an flapping-wing aircraft according to claim 3, characterized in that, The tail feathers include a central fixed tail feather (38) and multiple retractable tail feathers symmetrically arranged on both sides of the central fixed tail feather (38). The central fixed tail feather (38) is installed in the fixed tail feather mounting hole, and the multiple retractable tail feathers are installed one-to-one in the retractable tail feather mounting hole.

10. The multi-degree-of-freedom tail fin for an flapping-wing aircraft according to claim 9, characterized in that, The number of retractable tail feathers is eight; the number of tail feather mounting bases is eight.

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