Efficient small-scale bird-imitating ornithopter

Abstract

The invention discloses an efficient small-scale bird-imitating ornithopter, and belongs to the technical field of ornithopters. Comprising a fuselage, a flapping wing driving device and flapping wings, the flapping wing driving device comprises a flapping wing driving mechanism and a flapping wing flapping mechanism; rocker arm gear transmission structures which are meshed with each other are arranged on the inner side of a left rocker arm and the inner side of a right rocker arm of the flapping wing flapping mechanism respectively, a flapping wing is of a full-hand-wing structure, and the wing face of the flapping wing is a complete wing face which is of an integrated bilateral symmetry structure and formed by bonding a left flapping wing framework and a right flapping wing framework into a whole through skin. The wing span of the flapping wing is 0.3 m, the span-chord ratio of the flapping wing is 4, the tip-root ratio of the flapping wing is 1, the skin of the flapping wing is a polyester film, and the framework of the flapping wing is of a carbon fiber rod structure; the diameter of the main beam is 1 mm, the diameter of the oblique beam is 0.8 mm, and the diameters of the inner side wing rib beam and the outer side wing rib beam are both 0.6 mm. The unmanned aerial vehicle has the characteristics of high flight efficiency, high integration level, convenience in use and the like.

Description

Technical Field

[0001] The invention relates to the technical field of flapping-wing aircraft. Background Art

[0002] Flapping-wing aircraft has a wide range of application prospects due to its unique bionic shape and flight posture. Current prototype research is mainly focused on medium and large scale bird-like flapping-wing aircraft, and small scale bird-like flapping-wing aircraft prototypes are still rare.

[0003] At present, small-scale bird-like flapping wing aircraft generally have problems such as short flight time, weak load capacity, and poor autonomous flight ability. The flapping wings of medium- and large-scale bird-like flapping wing aircraft are composed of arm wings and hand wings. The arm wings are the parts corresponding to the humerus of bird wings. Since the arm wings located on the inner part of the flapping wing have greater rigidity, smaller movement amplitude, smaller geometric deformation amplitude, and weaker chord-wise deformation ability, they mainly generate upward lift and less forward thrust; the hand wings are the parts corresponding to the ulna and radius of bird wings. Since the wing ribs located on the outer part of the flapping wing are cantilever beam structures, they will also generate chord-wise deformation while maintaining up and down flapping, accelerate the airflow speed in the forward direction, and mainly generate forward thrust. However, since the flapping wings of medium- and large-scale bird-like flapping wing aircraft usually have larger wingspans and wing areas, they can relatively easily obtain the lift and thrust required for flight. In contrast, since the flapping wings of small-scale bird-like flapping wing aircraft are smaller in size, if a combined structure of arm wings and hand wings is adopted, it is more difficult to obtain thrust as a whole. On the other hand, the reduction in motor power density caused by size reduction and the greater viscosity loss caused by the reduction in Reynolds number have become more prominent, and the relevant devices have a greater contradiction in terms of function and size and weight under the constraint of small size. Therefore, the design of small-scale bird-like flapping-wing aircraft requires comprehensive optimization of the overall design of the aircraft, aerodynamics, power, energy, microelectronics and electromechanical manufacturing, so that it can generate greater forward thrust to overcome the problem of insufficient forward thrust of small-scale bird-like flapping-wing aircraft.

[0004] In summary, the development of practical high-performance small-scale bird-like flapping-wing aircraft still faces challenges. The present invention focuses on the engineering application development of small-scale bird-like flapping-wing aircraft, comprehensively designs and optimizes the relevant systems of the aircraft, and thus proposes an efficient small-scale bird-like flapping-wing aircraft. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a high-efficiency small-scale bird-like flapping-wing aircraft, which can overcome the problem of insufficient forward thrust existing in small-scale bird-like flapping-wing aircraft and has the characteristics of high flight efficiency, high integration, and convenient use.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0007] An efficient small-scale bird-like flapping-wing aircraft, comprising a fuselage, a flapping-wing driving device and flapping wings;

[0008] The flapping-wing drive device comprises a flapping-wing drive mechanism and a flapping-wing flapping mechanism;

[0009] The flapping-wing drive mechanism includes a motor and a reduction gear set arranged on a flapping-wing drive device frame, and the motor converts the low-torque and high-speed motion of the motor shaft into a low-speed and high-torque motion through the reduction gear set to drive the flapping-wing flapping mechanism to work;

[0010] The flapping mechanism comprises a rocker arm driving gear, a crank, a connecting rod, a left rocker arm and a right rocker arm; the middle parts of the left rocker arm and the right rocker arm are symmetrically arranged on the left and right sides of the fuselage through the rocker arm rotating shafts arranged on the frame of the flapping drive device, respectively; the inner sides of the left rocker arm and the right rocker arm are respectively provided with mutually meshing rocker arm gear transmission structures, so that the left rocker arm and the right rocker arm can swing synchronously under the action of the rocker arm gear transmission structures; the rocker arm driving gear is rotatably connected to the frame of the flapping drive device, one end of the crank is fixedly connected to the front end of the driving gear shaft of the rocker arm driving gear, the other end of the crank is hinged to the lower end of the connecting rod, and the upper end of the connecting rod is hinged to the left rocker arm or the right rocker arm;

[0011] When the motor drives the rocker arm driving gear to rotate through the reduction gear set, the crank drives the connecting rod to make the left rocker arm or the right rocker arm swing up and down. Under the action of the rocker arm gear transmission structure, the left rocker arm and the right rocker arm swing synchronously to produce a flapping motion;

[0012] The flapping wing is a full hand-wing structure, and the wing surface of the flapping wing is a complete wing surface of an integrated left-right symmetrical structure formed by bonding a left flapping wing frame and a right flapping wing frame together through a skin;

[0013] The left flapping wing frame and the right flapping wing frame are bilaterally symmetrical structures, and are mainly composed of a main beam, an oblique beam, an inner wing rib beam and an outer wing rib beam connected together: the main beam is arranged along the wingspan direction, the front end of the oblique beam is fixedly connected to the outer end of the main beam, and is inclined from front to back to the inner end of the flapping wing, the inner wing rib beam and the outer wing rib beam are arranged along the wingspan direction, and are fixed together with the main beam and the oblique beam, thereby forming a flapping wing frame;

[0014] The front end of the inner wing rib beam is located at 33% of the distance between the main beam and the inner end of the main beam, and is inclined from front to back toward the outer side of the flapping wing at an angle of 80° with the main beam. The front end of the outer wing rib beam is located at 57% of the distance between the main beam and the inner end of the main beam, and is inclined from front to back toward the outer side of the flapping wing at an angle of 39° with the main beam.

[0015] The wingspan of the flapping wing is 0.3m, the aspect ratio of the flapping wing is 4, the tip-root ratio of the flapping wing is 1, the skin of the flapping wing is polyester film, and the flapping wing frame is a carbon fiber rod structure;

[0016] The diameter of the main beam is 1mm, the diameter of the diagonal beam is 0.8mm, and the diameters of the inner and outer rib beams are both 0.6mm;

[0017] The outer end of the left rocker arm is plug-fitted and connected with the inner end of the main beam of the left flapping wing frame; the outer end of the right rocker arm is plug-fitted and connected with the inner end of the main beam of the right flapping wing frame.

[0018] The present invention is further improved in that:

[0019] The frame of the flapping-wing driving device includes a front wall plate and a rear wall plate; the reduction gear group includes a motor shaft gear, a primary gear and a secondary gear; the motor is fixedly installed at the rear of the rear wall plate, the motor shaft gear is fixedly connected to the motor shaft, the primary gear and the secondary gear are fixed together coaxially through the reduction gear shaft, the diameter of the primary gear is larger than the diameter of the secondary gear, the front end and the rear end of the reduction gear shaft are rotatably connected to the front wall plate and the rear wall plate respectively, the motor shaft gear is meshed with the primary gear, the secondary gear is meshed with the rocker arm driving gear, and the rear end of the driving gear shaft is rotatably connected to the rear wall plate; the rocker arm rotating shaft of the left rocker arm and the rocker arm rotating shaft of the right rocker arm are respectively installed between the front wall plate and the rear wall plate.

[0020] A fuselage connection hole is also provided on the skin behind the left-right symmetry line of the flapping wing for connection with the fuselage, thereby providing auxiliary connection for the flapping wing.

[0021] The body is carbon rod.

[0022] The beneficial effects of adopting the above technical solution are:

[0023] The flapping wing of the present invention adopts a full-hand wing design, which can obtain large deformation at a small scale to obtain greater thrust. It adopts a structure in which the left wing and the right wing are connected together to form a complete wing surface with an integrated left-right symmetrical structure to produce better lift characteristics; the inner sides of the left rocker arm and the right rocker arm are respectively provided with mutually meshing rocker arm gear transmission structures. Through the highly integrated design of related components, the small-scale flapping-wing aircraft still has practical functions while meeting the constraints of small size, thereby filling the gap in the current small-scale bird-like flapping-wing aircraft. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the structure of the present invention;

[0025] Figure 2 yes Figure 1 Schematic diagram of the local structure;

[0026] Figure 3 yes Figure 1 Axonometric view of the mid-flapping wing drive;

[0027] Figure 4 yes Figure 3 A partial axonometric drawing of

[0028] Figure 5 yes Figure 1 Schematic diagram of the structure of the mid-flapping wing;

[0029] Figure 6 It is the combined grid adopted by Fluent software for calculation;

[0030] Figure 7 It is the internal flow field grid taken by Fluent software for calculation;

[0031] Figure 8 to Figure 10 is the thrust coefficient of the flat airfoil at different pitch amplitudes with a flapping frequency of 10 Hz and a flapping amplitude of 60 degrees;

[0032] Figure 8 It is the curve when the spanwise position is 0.25;

[0033] Fig. 9 It is the curve when the spanwise position is 0.5;

[0034] Fig.10 It is the curve when the spanwise position is 0.75;

[0035] Figure 11 to Figure 13 The thrust coefficient of the flat airfoil at different pitch amplitudes with a flapping frequency of 15 Hz and a flapping amplitude of 60 degrees is

[0036] Fig.11 It is the curve when the spanwise position is 0.25;

[0037] Fig.12 It is the curve when the spanwise position is 0.5;

[0038] Fig.13 It is the curve when the spanwise position is 0.75;

[0039] Figure 14 to Figure 16 is the thrust coefficient of the flat airfoil at different pitch amplitudes with a flapping frequency of 20 Hz and a flapping amplitude of 60 degrees;

[0040] Fig.14 It is the curve when the spanwise position is 0.25;

[0041] Fig.15 It is the curve when the spanwise position is 0.5;

[0042] Fig.16 It is the curve when the spanwise position is 0.75;

[0043] In the attached drawings: 1. Carbon rod; 2. Fuselage shell; 3. Motor; 4. Rear wall panel; 5. Front wall panel; 6. Motor shaft gear; 7. Primary gear; 8. Reduction gear shaft; 9. Driving gear shaft; 10. Rocker arm driving gear; 11. Crank; 12. Connecting rod; 13. Left rocker arm; 14. Right rocker arm; 15. Rocker arm shaft; 16. Skin; 17. Main beam; 18. Oblique beam; 19. Inner wing rib beam; 20. Outer wing rib beam; 21. Fuselage connection hole; 22. Multi-function hardware system; 23. Miniature camera; 24. Horizontal stabilizer; 25. Vertical stabilizer; 26. Miniature servo; 27. Servo pull rod; 28. Control surface; 29. ​​Secondary gear. DETAILED DESCRIPTION

[0044] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0045] The standard parts used in the present invention can all be purchased from the market, and special-shaped parts can be customized according to the description in the specification and the drawings. The specific connection methods of each part adopt conventional means such as mature bolts, rivets, welding, and bonding in the prior art, which will not be described in detail here.

[0046] Depend on Figures 1 to 16 As can be seen from the embodiment shown, this embodiment includes a fuselage, a flapping-wing drive device and a flapping wing;

[0047] The flapping-wing drive device comprises a flapping-wing drive mechanism and a flapping-wing flapping mechanism;

[0048] The flapping-wing driving mechanism comprises a motor 3 and a reduction gear set arranged on a frame of the flapping-wing driving device, and the motor 3 converts the low-torque and high-speed motion of the motor shaft into a low-speed and high-torque motion through the reduction gear set to drive the flapping-wing flapping mechanism to work;

[0049] The flapping mechanism comprises a rocker arm driving gear 10, a crank 11, a connecting rod 12, a left rocker arm 13 and a right rocker arm 14; the middle parts of the left rocker arm 13 and the right rocker arm 14 are symmetrically arranged on the left and right sides of the fuselage through a rocker arm rotating shaft 15 arranged on the frame of the flapping drive device, and are rotatably connected with the rocker arm rotating shaft 15, and the inner sides of the left rocker arm 13 and the right rocker arm 14 are respectively provided with mutually meshing rocker arm gear transmission structures, so that the left rocker arm 13 and the right rocker arm 14 swing synchronously under the action of the rocker arm gear transmission structure; the rocker arm driving gear 10 is rotatably connected to the frame of the flapping drive device, one end of the crank 11 is fixedly connected to the front end of the driving gear shaft 9 of the rocker arm driving gear 10, the other end of the crank 11 is hinged to the lower end of the connecting rod 12, and the upper end of the connecting rod 12 is hinged to the left rocker arm 13 or the right rocker arm 14;

[0050] When the motor 3 drives the rocker arm driving gear 10 to rotate through the reduction gear set, the crank 11 drives the connecting rod 12 to make the left rocker arm 13 or the right rocker arm 14 swing up and down. Under the action of the rocker arm gear transmission structure, the left rocker arm 13 and the right rocker arm 14 swing synchronously to generate a flapping motion;

[0051] The flapping wing is a full hand-wing structure, and the wing surface of the flapping wing is a complete wing surface of an integrated left-right symmetrical structure formed by bonding the left flapping wing frame and the right flapping wing frame together through a skin 16;

[0052] The left flapping wing frame and the right flapping wing frame are bilaterally symmetrical structures, and are mainly composed of a main beam 17, an oblique beam 18, an inner wing rib beam 19 and an outer wing rib beam 20 connected together: the main beam 17 is arranged along the wingspan direction, the front end of the oblique beam 18 is fixedly connected to the outer end of the main beam 17, and is inclined from front to back to the inner end of the flapping wing, the inner wing rib beam 19 and the outer wing rib beam 20 are arranged along the wingspan direction, and are fixed together with the main beam 17 and the oblique beam 18, thereby forming a flapping wing frame;

[0053] The front end of the inner wing rib beam 19 is located at 33% of the distance between the main beam 17 and the inner end of the main beam, and is inclined from front to back toward the outer side of the flapping wing at an angle of 80° with the main beam 17. The front end of the outer wing rib beam 20 is located at 57% of the distance between the main beam 17 and the inner end of the main beam 17, and is inclined from front to back toward the outer side of the flapping wing at an angle of 39° with the main beam 17.

[0054] The wingspan of the flapping wing is 0.3 m, the aspect ratio of the flapping wing is 4, the tip-root ratio of the flapping wing is 1, the skin 16 of the flapping wing is a polyester film, and the flapping wing frame is a carbon fiber rod structure;

[0055] The diameter of the main beam 17 is 1 mm, the diameter of the diagonal beam 18 is 0.8 mm, and the diameters of the inner rib beam 19 and the outer rib beam 20 are both 0.6 mm;

[0056] The flapping wing frame, flapping wing frame material and specifications enable the flapping wing to form a full-hand flapping wing structure.

[0057] The outer end of the left rocker arm 13 is plug-fitted and connected to the inner end of the main beam 17 of the left flapping wing frame; the outer end of the right rocker arm 14 is plug-fitted and connected to the inner end of the main beam 17 of the right flapping wing frame.

[0058] The frame of the flapping-wing drive device includes a front wall plate 5 and a rear wall plate 4; the reduction gear group includes a motor shaft gear 6, a primary gear 7 and a secondary gear 29; the motor 3 is fixedly installed at the rear of the rear wall plate 4, the motor shaft gear 6 is fixedly connected to the motor shaft, the primary gear 7 and the secondary gear 29 are fixed together coaxially through the reduction gear shaft 8, the diameter of the primary gear 7 is larger than the diameter of the secondary gear 29, the front end and the rear end of the reduction gear shaft 8 are respectively rotatably connected to the front wall plate 5 and the rear wall plate 4, the motor shaft gear 6 is meshed with the primary gear 7, the secondary gear 29 is meshed with the rocker arm driving gear 10, and the rear end of the driving gear shaft 9 is rotatably connected to the rear wall plate 4; the rocker arm rotating shaft 15 of the left rocker arm 13 and the rocker arm rotating shaft 15 of the right rocker arm 14 are respectively installed between the front wall plate 5 and the rear wall plate 4.

[0059] A fuselage connection hole 21 is also provided on the skin behind the left-right symmetry line of the flapping wing for connection with the fuselage, thereby providing auxiliary connection for the flapping wing.

[0060] The body is a carbon rod 1.

[0061] Working mechanism that generates strong forward thrust

[0062] The flapping wing in the present invention is a full hand-wing structure, which imitates the active deformation of small birds during flapping through passive flexible deformation to obtain greater thrust at a small scale. Under the action of aerodynamic force, the flapping wing will undergo obvious flexible deformation, and there is an optimal torsional deformation for the flexible deformation, so that the thrust generated by the flapping wing is maximized. The flexible deformation of the three-dimensional flapping wing can be regarded as the torsional deformation of the two-dimensional flat airfoil at different spanwise positions. Therefore, by simplifying the flexible deformation and waving motion of the three-dimensional flapping wing into the pitching and sinking motion of the two-dimensional flat airfoil, the pitch amplitude is used to simulate different degrees of flexibility to determine the optimal deformation corresponding to the maximum thrust. The motion law corresponding to the two-dimensional airfoil is as follows:

[0063] h(t)=h m cos(2πft)

[0064]

[0065] Where h(t) is the rise and fall amplitude of the airfoil at different times at each station, h m is the buoyancy amplitude at each station, f is the flapping frequency, t is the time, θ(t) is the pitch amplitude of the airfoil at each station at different times, θ m is the pitch amplitude of each station.

[0066] Fluent software is used to calculate the pitch, sink and float motion of a two-dimensional flat airfoil. The flat airfoil is a flat plate with a chord length of 100 mm and a thickness of 2 mm. The inner flow field is a rectangular area, with the front boundary 5 times the chord length from the leading edge of the flat plate, the rear boundary 8 times the chord length from the leading edge of the flat plate, and the upper and lower boundaries 5 times the chord length from the leading edge of the flat plate respectively. The outer flow field is also a rectangular area, with the front boundary 20 times the chord length from the leading edge of the flat plate, the rear boundary 35 times the chord length from the leading edge of the flat plate, and the upper and lower boundaries 20 times the chord length from the leading edge of the flat plate respectively. The mesh size of the inner flow field is 69088, the mesh size of the outer flow field is 31110, and the total mesh size is about 10w. This mesh size can ensure that the unsteady calculation of the two-dimensional airfoil has a high accuracy. The schematic diagram of the calculated mesh is shown below. Figure 6 , Figure 7 shown.

[0067] The calculation states include different wind speeds, flapping frequencies and spanwise positions, and the specific calculation parameters are shown in Table 1. Among them, the airfoils at different spanwise positions have different sinking and floating amplitudes.

[0068] Table 1 Calculation parameters

[0069]

[0070] The thrust coefficients calculated under various conditions are as follows: Figures 8 to 16 shown.

[0071] Figure 8 to Figure 10 It is the thrust coefficient of the flat airfoil at a flapping frequency of 10 Hz, a flapping amplitude of 60 degrees and different pitch amplitudes.

[0072] Figure 11 to Figure 13 It is the thrust coefficient of the flat airfoil at a flapping frequency of 15 Hz, a flapping amplitude of 60 degrees and different pitch amplitudes.

[0073] Figure 14 to Figure 16 It is the thrust coefficient of the flat airfoil at a flapping frequency of 20 Hz, a flapping amplitude of 60 degrees and different pitch amplitudes.

[0074] It can be seen from the figure that for each state, the thrust coefficient shows a similar trend of change. There is an optimal pitch amplitude that makes the thrust coefficient reach the maximum value. This also proves again that flexibility is not the greater the better, but there is an optimal value. As the wind speed increases, the thrust coefficient decreases. As the flapping frequency and spanwise occupancy increase, the thrust coefficient generated by the flat airfoil increases.

[0075] The pitch amplitude corresponding to the maximum thrust in each state and the effective angle of attack at the middle moment of flapping were counted. The calculation formula for the effective angle of attack of flapping is:

[0076]

[0077] Where: V is the cruising speed.

[0078] The corresponding effective angle of attack at the middle moment of the dive is:

[0079]

[0080] Tables 2, 3 and 4 respectively show the pitch amplitude corresponding to the effective angle of attack and the maximum thrust at the middle moment of the dive under various calculation states at different frequencies.

[0081] Table 2 Effective angle of attack and pitch amplitude in each state at flapping frequency of 10 Hz

[0082]

[0083] Table 3 Effective angle of attack and pitch amplitude in each state at flapping frequency of 15 Hz

[0084]

[0085]

[0086] Table 4 Effective angle of attack and pitch amplitude in each state at flapping frequency of 20 Hz

[0087]

[0088] It can be found from the table that, except for some cases where the spanwise position is 0.25, in most cases, the optimal pitch amplitude required for maximum thrust is close to the effective angle of attack at the middle of the dive. Therefore, it can be considered that the optimal flexible deformation required for maximum thrust is equal to the effective angle of attack at the middle of the dive, that is, half of the induced angle of attack at the middle of the dive, as shown in the following formula.

[0089]

[0090] The flapping wing designed according to the above deformation law is a small-scale flapping wing with optimal flexible deformation, the wingspan of the flapping wing is 0.3m, the aspect ratio of the flapping wing is 4, the tip-root ratio of the flapping wing is 1, the skin of the flapping wing is a polyester film, the flapping wing skeleton is a carbon fiber rod structure, the first wing rib is located at 33% of the distance between the main beam and the inner end of the main beam, and is inclined from front to back to the outer side of the flapping wing at an angle of 80° with the main beam, and the second wing rib is located at 57% of the distance between the main beam and the inner end of the main beam, and is inclined from front to back to the outer side of the flapping wing at an angle of 39° with the main beam; the diameter of the main beam is 1mm, the diameter of the oblique beam is 0.8mm, and the diameters of the first wing rib and the second wing rib are 0.6mm.

Claims

1. An efficient small-scale bird-like flapping-wing aircraft, comprising a fuselage, a flapping-wing drive device and flapping wings, characterized in that: The flapping-wing drive device comprises a flapping-wing drive mechanism and a flapping-wing flapping mechanism; The flapping-wing driving mechanism comprises a motor (3) and a reduction gear set arranged on a flapping-wing driving device frame, wherein the motor (3) converts the low-torque and high-speed motion of the motor shaft into low-speed and high-torque motion through the reduction gear set to drive the flapping-wing flapping mechanism to work; The flapping mechanism comprises a rocker arm driving gear (10), a crank (11), a connecting rod (12), a left rocker arm (13) and a right rocker arm (14); the middle parts of the left rocker arm (13) and the right rocker arm (14) are symmetrically arranged on the left and right sides of the fuselage through rocker arm rotating shafts (15) arranged on the frame of the flapping drive device, and the inner sides of the left rocker arm (13) and the right rocker arm (14) are respectively provided with mutually meshing rocker arm gear transmission structures so that the left rocker arm (13) and the right rocker arm (14) are respectively arranged. (13) and the right rocker arm (14) swing synchronously under the action of the rocker arm gear transmission structure; the rocker arm driving gear (10) is rotatably connected to the frame of the flapping-wing driving device, one end of the crank (11) is fixedly connected to the front end of the driving gear shaft (9) of the rocker arm driving gear (10), the other end of the crank (11) is hinged to the lower end of the connecting rod (12), and the upper end of the connecting rod (12) is hinged to the left rocker arm (13) or the right rocker arm (14); When the motor (3) drives the rocker arm driving gear (10) to rotate via the reduction gear set, the crank (11) drives the connecting rod (12) to make the left rocker arm (13) or the right rocker arm (14) swing up and down, and under the action of the rocker arm gear transmission structure, the left rocker arm (13) and the right rocker arm (14) swing synchronously to generate a flapping motion; The flapping wing is a full hand-wing structure, and the wing surface of the flapping wing is a complete wing surface of an integrated left-right symmetrical structure formed by bonding a left flapping wing frame and a right flapping wing frame together through a skin (16); The left flapping wing frame and the right flapping wing frame are bilaterally symmetrical structures, and are mainly composed of a main beam (17), an oblique beam (18), an inner wing rib beam (19) and an outer wing rib beam (20) connected together: the main beam (17) is arranged along the wingspan direction, the front end of the oblique beam (18) is fixedly connected to the outer end of the main beam (17), and is inclined from front to back to the inner end of the flapping wing, the inner wing rib beam (19) and the outer wing rib beam (20) are arranged along the wingspan direction, and are fixed together with the main beam (17) and the oblique beam (18), so as to form a flapping wing frame; The front end of the inner wing rib beam (19) is located at a position 33% of the distance between the main beam (17) and the inner end of the main beam, and is inclined from front to back toward the outer side of the flapping wing at an angle of 80° with the main beam (17); the front end of the outer wing rib beam (20) is located at a position 57% of the distance between the main beam (17) and the inner end of the main beam (17), and is inclined from front to back toward the outer side of the flapping wing at an angle of 39° with the main beam (17); The wingspan of the flapping wing is 0.3 m, the aspect ratio of the flapping wing is 4, the tip-to-root ratio of the flapping wing is 1, the skin (16) of the flapping wing is a polyester film, and the flapping wing skeleton is a carbon fiber rod structure; The diameter of the main beam (17) is 1 mm, the diameter of the oblique beam (18) is 0.8 mm, and the diameters of the inner wing rib beam (19) and the outer wing rib beam (20) are both 0.6 mm; The outer end of the left rocker arm (13) is plug-fitted and connected to the inner end of the main beam (17) of the left flapping wing frame; the outer end of the right rocker arm (14) is plug-fitted and connected to the inner end of the main beam (17) of the right flapping wing frame.

2. The high-efficiency small-scale bird-like flapping-wing aircraft according to claim 1, characterized in that: The frame of the flapping-wing driving device comprises a front wall plate (5) and a rear wall plate (4); the reduction gear set comprises a motor shaft gear (6), a primary gear (7) and a secondary gear (29); the motor (3) is fixedly mounted behind the rear wall plate (4); the motor shaft gear (6) is fixedly connected to the motor shaft; the primary gear (7) and the secondary gear (29) are coaxially fixed together via a reduction gear shaft (8); the diameter of the primary gear (7) is greater than the diameter of the secondary gear (29); the reduction gear (8) is The front end and the rear end of the wheel shaft (8) are rotatably connected to the front wall plate (5) and the rear wall plate (4) respectively; the motor shaft gear (6) is meshedly connected to the primary gear (7); the secondary gear (29) is meshedly connected to the rocker arm driving gear (10); the rear end of the driving gear shaft (9) is rotatably connected to the rear wall plate (4); the rocker arm rotating shaft (15) of the left rocker arm (13) and the rocker arm rotating shaft (15) of the right rocker arm (14) are respectively installed between the front wall plate (5) and the rear wall plate (4).

3. A high-efficiency small-scale bird-like flapping-wing aircraft according to claim 1 or 2, characterized in that: A fuselage connection hole (21) is also provided on the skin behind the left-right symmetry line of the flapping wing for connection with the fuselage, thereby providing auxiliary connection for the flapping wing.

4. The high-efficiency small-scale bird-like flapping-wing aircraft according to claim 3, characterized in that: The fuselage is a carbon rod (1).

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