A flapping wing structure and aircraft

Abstract

This invention discloses a flapping wing structure and aircraft, including a fixed frame, a reciprocating assembly, and flapping wing assemblies. The fixed frame includes a rectangular frame, and the reciprocating assembly can reciprocate along the longitudinal direction of the rectangular frame. Two flapping wing assemblies are symmetrically mounted on opposite sides of the rectangular frame. Each flapping wing assembly includes a flapping wing, a first connecting rod, and a second connecting rod. One end of the first connecting rod is rotatably connected to a side frame of the rectangular frame, and the other end is fixedly connected to the second connecting rod. The second connecting rod and the first connecting rod form an L-shaped structure. One end of the flapping wing passes through the second connecting rod and is fixedly connected to a driven bevel gear. A connecting shaft is rotatably mounted on the first connecting rod, and a driving bevel gear is fixedly mounted at one end of the connecting shaft, meshing with the driven bevel gear. This invention can simultaneously achieve flapping and flipping movements of the wings without requiring additional power, simplifying the drive mechanism.

Description

Technical Field

[0001] This invention relates to the field of aircraft technology, specifically to a flapping wing structure and an aircraft. Background Technology

[0002] In recent years, numerous scholars and engineers have begun to recognize the vast application prospects of micro unmanned aerial vehicles (UAVs). Micro UAVs possess significant advantages in fields such as disaster relief, exploration, and reconnaissance. Due to their small size, micro UAVs can enter complex spaces to perform specialized tasks. Compared to ground-based microrobots, micro UAVs, possessing flight capabilities, can find the shortest path in complex environments without being limited by ground conditions, quickly completing mission objectives. Military scientists are also increasingly recognizing the irreplaceable role of micro UAVs in the future digital and information-based battlefield, and the development of micro UAVs has high scientific and engineering value.

[0003] Bionic flapping-wing micro-aircraft are aircraft that are inspired by insects and birds. Compared with rotor mechanisms, fixed-wing mechanisms, and other mechanisms, flapping-wing mechanisms have significant flexibility, maneuverability, and stealth.

[0004] For flapping-wing aircraft, the design of the flapping wing mechanism is crucial to the overall aerodynamic performance and flight efficiency. Most existing flapping-wing aircraft, both domestically and internationally, can only achieve a single flapping motion. For the roll motion, most rely on passive adjustment through aerodynamic forces acting on the flexible wing to deform it, lacking active control and resulting in insufficient kinetic and controllable forces. Flapping-wing aircraft with controllable roll motion mostly employ a series mechanism design; however, series drive mechanisms are cumbersome and inefficient.

[0005] Therefore, how to design a flapping wing structure that can autonomously perform a flipping motion during flapping is one of the problems that urgently needs to be solved in this field. Summary of the Invention

[0006] The purpose of this invention is to provide a flapping wing structure and an aircraft to overcome the shortcomings of the prior art.

[0007] This invention provides a flapping wing structure, including a fixed frame, a reciprocating assembly, and flapping wing assemblies. The fixed frame includes a rectangular frame, and the reciprocating assembly is capable of reciprocating along the longitudinal direction of the rectangular frame. There are two flapping wing assemblies, which are symmetrically installed on opposite sides of the rectangular frame. Each flapping wing assembly includes a flapping wing, a first connecting rod, and a second connecting rod. One end of the first connecting rod is rotatably connected to a side frame of the rectangular frame, and the other end is fixedly connected to the second connecting rod. The second connecting rod and the first connecting rod form an L-shaped structure. One end of the flapping wing passes through the second connecting rod and is fixedly connected to a driven bevel gear. A connecting shaft is rotatably mounted on the first connecting rod, and a driving bevel gear is fixedly mounted on one end of the connecting shaft. The driving bevel gear meshes with the driven bevel gear. The other end of the connecting shaft is fixedly connected to one end of a third connecting rod, and the other end of the third connecting rod is hinged to the reciprocating assembly.

[0008] Furthermore, the fixing frame also includes a first support rod and a second support rod. The first support rod is perpendicular to the rectangular frame, and the second support rod is perpendicular to the end of the first support rod away from the rectangular frame. The second support rod is parallel to the rectangular frame. The reciprocating assembly includes a fourth connecting rod. The two ends of the fourth connecting rod are respectively hinged to the two third connecting rods. A fixing rod is provided in the middle of the fourth connecting rod. The fixing rod is hinged to one end of a sixth connecting rod through a fifth connecting rod. The other end of the sixth connecting rod passes through the rectangular frame and is hinged to the second support rod. The sixth connecting rod can move along the longitudinal direction of the rectangular frame.

[0009] Furthermore, it also includes a drive assembly, which includes a drive motor. The output shaft of the drive motor is provided with a motor gear, which meshes with a reduction gear. The reduction gear is hinged to the fourth connecting rod via a seventh connecting rod, and the hinge point between the seventh connecting rod and the reduction gear is offset from the center of the reduction gear.

[0010] Furthermore, the mounting bracket is fixedly connected to the outer shell of the aircraft.

[0011] The present invention also provides an aircraft comprising two sets of flapping wing structures as described above. The two sets of flapping wing structures respectively constitute the front wing and rear wing of the aircraft. The drive motor of the flapping wing structure is mounted on a bracket, and the bracket is fixedly connected to the shell of the aircraft. The two sets of flapping wing structures are symmetrically arranged on both sides of the bracket.

[0012] Furthermore, the bracket includes two parallel support plates, which are parallel to the rectangular frame; two drive motors are fixedly installed between the two support plates and are located at opposite ends of the support plates, with the output shafts of the two drive motors facing opposite directions and respectively passing through the corresponding support plates and fixedly connected to the corresponding motor gears; two reduction gears are rotatably installed on the two support plates and are located on the side of the two support plates away from each other, with the center lines of the two reduction gears on the same straight line, and the center lines of the two reduction gears and the centers of the two drive motors in the same plane.

[0013] Furthermore, a phase difference adjustment structure is provided between the two sets of flapping wing structures. The phase difference adjustment structure includes a connecting block, a placement plate, and an attitude sensor. Each of the fourth connecting rods has two connecting ears, which are arranged opposite to each other. There are two connecting blocks, which are rotatably mounted on the two connecting ears of one fourth connecting rod. Each of the two connecting blocks has a sliding groove adapted to the placement plate on its opposite side. One end of the placement plate is slidably mounted between the two connecting blocks, and the other end of the placement plate is hinged to the two connecting ears on the other fourth connecting rod. The attitude sensor is fixedly mounted on the placement plate.

[0014] Furthermore, the edge of the attitude sensor is parallel to the edge of the shelf, the attitude sensor detects the tilt angle of the shelf relative to the fixing frame, determines the maximum value of the tilt angle, and calculates the actual phase difference between the two flapping wing structures based on the maximum value.

[0015] Furthermore, it also includes a controller, which is electrically connected to the attitude sensor and the drive motor; the controller is used to acquire the target phase difference between the two flapping wing structures and calculate the phase difference value to be adjusted based on the actual phase difference; the controller is also used to adjust the rotational speed of at least one of the drive motors based on the phase difference value until the actual phase difference is equal to the target phase difference.

[0016] Compared with existing technologies, this invention can simultaneously achieve flapping and tumbling movements of the wings without the need for additional power, simplifying the drive mechanism, enabling active control, and improving the aircraft's motion and control. The aircraft of this invention can adjust the phase difference between the fore and rear wings in real time during flight, effectively meeting the aerodynamic requirements of different flight modes. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of a first embodiment of the flapping wing structure proposed in this invention;

[0018] Figure 2 yes Figure 1 A structural diagram from another perspective;

[0019] Figure 3 This is a schematic diagram of a second embodiment of the flapping wing structure proposed in this invention;

[0020] Figure 4 This is a schematic diagram of the structure of an aircraft proposed in this invention:

[0021] Figure 5 yes Figure 4 The main view.

[0022] Explanation of reference numerals in the attached figures:

[0023] 1 - Fixed frame, 2 - Wing assembly, 101 - Rectangular frame, 201 - Flap wing, 202 - First connecting rod, 203 - Second connecting rod, 3 - Driven bevel gear, 4 - Connecting shaft, 5 - Driving bevel gear, 6 - Third connecting rod, 102 - First support rod, 103 - Second support rod, 7 - Fourth connecting rod, 8 - Fixed rod, 9 - Fifth connecting rod, 10 - Sixth connecting rod, 11 - Drive motor, 12 - Motor gear, 13 - Reduction gear, 14 - Seventh connecting rod, 15 - Support plate, 16 - Connecting block, 17 - Storage plate, 18 - Connecting ear, 1601 - Slide groove. Detailed Implementation

[0024] The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0025] Embodiment 1 of the present invention:

[0026] This invention proposes a flapping wing structure (see reference). Figure 1 and Figure 2 It includes a fixed frame 1, a reciprocating assembly and two flapping wing assemblies 2; the fixed frame 1 includes a rectangular frame 101 with a rectangular hole inside. The rectangular frame 101 is used to directly or indirectly limit the reciprocating assembly so that the reciprocating assembly can only move back and forth along the length direction of the rectangular hole of the rectangular frame 101.

[0027] The reciprocating assembly can reciprocate along the longitudinal direction of the rectangular frame 101, where the longitudinal direction refers to the length of the rectangular frame 101. The reciprocating motion of the reciprocating assembly drives the flapping and flipping motions of the two flapping wing assemblies 2. The two flapping wing assemblies 2 are symmetrically installed on opposite sides of the rectangular frame 101. Specifically, the flapping wing mechanism has forward / backward, left / right, and up / down directions; these directions are mutually perpendicular, and the forward / backward, left / right, and up / down directions referred to here are consistent with the forward / backward, left / right, and up / down directions of the aircraft on which the flapping wing structure is located. In implementation, the length direction of the rectangular hole is the up / down direction, and the centerline direction of the rectangular hole is the forward / backward direction. In specific implementation, the two flapping wing assemblies 2 are distributed correspondingly to the left and right along the vertical center plane.

[0028] The flapping wing assembly 2 includes flapping wings 201, a first connecting rod 202, and a second connecting rod 203; the two flapping wings 201 extend outward in the left and right directions, respectively. One end of the first connecting rod 202 is rotatably connected to one side frame of the rectangular frame 101, and the other end is fixedly connected to the second connecting rod 203. Specifically, one end of the first connecting rod 202 is rotatably connected to a long side frame of the rectangular frame 101 via a pin. The rotation center line of the first connecting rod 202 is perpendicular to the plane of the rectangular frame 101. The second connecting rod 203 is fixedly perpendicular to the first connecting rod 202. The second connecting rod 203 and the first connecting rod 202 form an L-shaped structure. One end of the flapping wing 201 passes through the second connecting rod 203 and is fixedly connected to a driven bevel gear 3. To facilitate rotation, the flapping wing 201 has a connecting handle along its length. The cross-section of the connecting handle is cylindrical. The connecting handle passes through the second connecting rod 203 and is rotatably connected to the second connecting rod 203. The driven bevel gear 3 is fixedly installed on the second connecting rod 203. The end of the first connecting rod 202 away from its rotation center rotates... A connecting shaft 4 is mounted on the convex structure, through which a first connecting rod 202 extends. A driving bevel gear 5 is fixedly mounted at one end of the connecting shaft 4, meshing with a driven bevel gear 3. The other end of the connecting shaft 4 is fixedly connected to one end of a third connecting rod 6, which is hinged to a reciprocating assembly. When the reciprocating assembly moves reciprocally along the longitudinal direction of the rectangular frame 101, it drives the third connecting rod 6 to swing along the centerline of the connecting shaft 4. Simultaneously, the swinging of the third connecting rod 6 drives the first connecting rod 202 to swing back and forth along its swing centerline, thus achieving the flapping motion of the flapping wing 201. At the same time, the third connecting rod 6 drives the connecting shaft 4 to rotate, which in turn drives the driving bevel gear 5 to rotate. The driving bevel gear 5 then drives the driven bevel gear 3 to rotate, which in turn causes the flapping wing 201 to flip. Thus, the flapping motion and flipping motion of the flapping wing 201 can be achieved simultaneously. This eliminates the need for additional power to achieve the flipping motion of the flapping wing 201, simplifying the drive mechanism, enabling active control, and improving the aircraft's motion and control capabilities.

[0029] In a preferred embodiment, the fixing frame 1 further includes a first support rod 102 and a second support rod 103. The first support rod 102 is vertically fixed to the rectangular frame 101 and is located on the side of the rectangular frame 101 away from the reciprocating assembly. The axis of the first support rod 102 is in the same plane as the center line of the width direction of the rectangular frame 101. The second support rod 103 is vertically located at the end of the first support rod 102 away from the rectangular frame 101. The second support rod 103 is parallel to the rectangular frame 101 and is arranged along the length direction of the rectangular frame 101. The reciprocating assembly includes a fourth connecting rod 7. The two ends of the fourth connecting rod 7 are respectively hinged to two third connecting rods 6. A fixing rod 8 is provided in the middle of the fourth connecting rod 7. The fixing rod 8 is hinged to one end of a sixth connecting rod 10 through a fifth connecting rod 9. Specifically, the two ends of the fifth connecting rod 9 are respectively hinged to the fixing rod 8 and the sixth connecting rod 10. The other end of the sixth connecting rod 10 passes through the rectangular frame 101 and is hinged to the second support rod 103, allowing the sixth connecting rod 10 to swing along the longitudinal direction of the rectangular frame 101. In practice, the sixth connecting rod 10 is slidably connected to the inner wall of the rectangular frame 101. By setting the first support rod 102, the second support rod 103, the fixed rod 8, the fifth connecting rod 9, and the sixth connecting rod 10, the reciprocating assembly can move more smoothly along the longitudinal direction of the rectangular frame 101, reducing lateral swaying. To further reduce lateral swaying, the width of the inner frame of the rectangular frame 101 can be designed to fit the size of the sixth connecting rod 10. Alternatively, two second support rods 103 can be provided, with the two second support rods 103 respectively positioned opposite each other on both sides of the first support rod 102. The sixth connecting rod 10 is positioned between the two second support rods 103 and is hinged to both second support rods 103. The end of the sixth connecting rod 10 that is hinged to the fifth connecting rod 9 has a first receiving groove, which is a U-shaped through groove. One end of the fifth connecting rod 9 is inserted into the first receiving groove and is hinged to the two side walls of the first receiving groove. The end of the fixing rod 8 near the fifth connecting rod 9 has a second receiving groove, which is a U-shaped through groove. One end of the fifth connecting rod 9 is inserted into the second receiving groove and is hinged to the two side walls of the second receiving groove.

[0030] In order to limit the reciprocating component, in other implementations, the fixed rod 8 can be directly set to slide along the rectangular frame 101, thereby eliminating the fifth connecting rod 9 and the sixth connecting rod 10, which simplifies the structure.

[0031] Example 2:

[0032] This embodiment is a further optimization based on Embodiment 1. The parts that are the same as in Embodiment 1 will not be repeated here; please refer to [the original document]. Figure 3This application also includes a drive assembly, which includes a drive motor 11. A motor gear 12 is mounted on the output shaft of the drive motor 11. The motor gear 12 meshes with a reduction gear 13. The reduction gear 13 is hinged to a fourth connecting rod 7 via a seventh connecting rod 14. The hinge point between the seventh connecting rod 14 and the reduction gear 13 is offset from the center of the reduction gear 13. This configuration allows the rotation of the drive motor 11 to be converted into reciprocating motion of the fourth connecting rod 7 along the length of the rectangular frame 101 via the motor gear 12, reduction gear 13, and seventh connecting rod 14. In some implementations, a crank-connecting rod mechanism can also be used to convert rotation into reciprocating motion. It should be noted that, to achieve the above functions, in specific implementations, the reciprocating assembly can achieve complete reciprocating motion within the rectangular hole of the rectangular frame 101.

[0033] The mounting bracket 1 is fixedly connected to the aircraft's outer shell. By fixing the mounting bracket 1 to the aircraft's outer shell, the flapping wing structure can be applied to the aircraft.

[0034] Example 3:

[0035] refer to Figure 4 - Figure 5 As shown, the present invention also proposes an aircraft comprising two sets of flapping wing structures as described above. The two sets of flapping wing structures respectively constitute the front wing and rear wing of the aircraft. The drive motor 11 of the flapping wing structure is mounted on a bracket, which is fixedly connected to the shell of the aircraft. The two sets of flapping wing structures are symmetrically arranged on both sides of the bracket. The bracket includes two parallel support plates 15, which are parallel to the rectangular frame 101. The two drive motors 11 are fixedly mounted between the two support plates 15 and are located at both ends of the support plates 15. Specifically, the two drive motors 11 are located at the upper and lower ends of the two support plates 15, respectively. The output shafts of the two drive motors 11 face opposite directions and are fixedly connected to the corresponding motor gears 12 through the corresponding support plates 15. The two reduction gears 13 are rotatably mounted on the two support plates 15 and are located on the side of the two support plates 15 away from each other. The center lines of the two reduction gears 13 are on the same straight line. In specific implementation, there is no power transmission between the two reduction gears 13. That is, although the center lines of the two reduction gears 13 are collinear, they are mounted through different shafts and can rotate at different speeds.

[0036] The center lines of the two reduction gears 13 and the centers of the two drive motors 11 are located in the same plane. The ends of the two support plates 15 are also provided with connecting plates, which connect the two ends of the two support plates 15 respectively, making the support structure more stable.

[0037] To achieve real-time adjustment of the phase difference during flight, this application makes the following improvements: a phase difference adjustment structure is provided between the two flapping wing structures. The phase difference adjustment structure includes a connecting block 16, a placement plate 17, and an attitude sensor 19. Each of the four connecting rods 7 is provided with two connecting ears 18, which are arranged opposite to each other. There are two connecting blocks 16, which are rotatably mounted on the two connecting ears 18 of one of the four connecting rods 7. Specifically, the two connecting blocks 16 are mounted on the side of the two connecting ears 18 that are close to each other, and the connecting blocks 16 and the connecting ears are connected by a connecting shaft. Each of the two connecting blocks 16 has a sliding groove 1601 adapted to the placement plate 17 on its opposite side. One end of the placement plate 17 is slidably mounted between the two connecting blocks 16, and the other end of the placement plate 17 is hinged to the two connecting ears 18 on the other four connecting rod 7. The attitude sensor 19 is fixedly mounted on the placement plate 17. With this design, the shelf 17 can slide within the groove 1601 and rotate along the hinge between the shelf 17 and the fourth connecting rod 7, providing conditions for real-time adjustment of the phase difference.

[0038] The edge of the attitude sensor 19 is parallel to the edge of the shelf 17. The attitude sensor 19 detects the tilt angle of the shelf 17 relative to the fixed frame 1, determines the maximum value of the tilt angle, and calculates the actual phase difference between the two flapping wing structures based on the maximum value.

[0039] It also includes a controller, which is electrically connected to the attitude sensor 19 and the drive motor 11. The controller is used to acquire the target phase difference between the two flapping wing structures and calculate the phase difference value to be adjusted based on the actual phase difference. The controller is also used to adjust the rotation speed of at least one drive motor 11 according to the phase difference value until the actual phase difference is equal to the target phase difference. In specific implementation, the phase difference can be adjusted by adjusting the rotation speed of any one drive motor 11, or by adjusting the rotation speed of both drive motors 11 simultaneously.

[0040] When the two drive motors 11 of the aircraft rotate, the forewing and rearwing begin to flap and rotate. At this time, there is a phase difference between the two drive motors 11. The attitude sensor 19 detects the tilt angle of the mounting plate 17 relative to the fixed frame 1, determines the maximum value of the tilt angle, and calculates the actual phase difference between the two flapping wing structures based on the maximum value. When the phase difference needs to be adjusted, the controller calculates the phase difference value to be adjusted based on the actual phase difference, and adjusts the rotation speed of at least one drive motor 11 according to the phase difference value until the actual phase difference is equal to the target phase difference.

[0041] The aircraft of this invention can adjust the phase difference between the fore and hind wings in real time during flight, which can well meet the aerodynamic requirements of different flight modes.

[0042] The above description, based on the embodiments shown in the figures, details the structure, features, and effects of the present invention. The above description is only a preferred embodiment of the present invention, but the present invention is not limited to the scope of implementation shown in the figures. Any changes made in accordance with the concept of the present invention, or equivalent embodiments modified to have equivalent changes, that do not exceed the spirit covered by the specification and figures, should be within the protection scope of the present invention.

Claims

1. A flapping wing structure, characterized in that: The system includes a fixed frame (1), a reciprocating assembly, and a flapping wing assembly (2). The fixed frame (1) includes a rectangular frame (101). The reciprocating assembly is capable of reciprocating along the longitudinal direction of the rectangular frame (101). There are two flapping wing assemblies (2), which are symmetrically installed on opposite sides of the rectangular frame (101). Each flapping wing assembly (2) includes flapping wings (201), a first connecting rod (202), and a second connecting rod (203). One end of the first connecting rod (202) is rotatably connected to one side frame of the rectangular frame (101), and the other end is connected to the second connecting rod (203). The first connecting rod (202) and the second connecting rod (203) form an L-shaped structure. One end of the flapping wing (201) passes through the second connecting rod (203) and is fixedly connected to a driven bevel gear (3). A connecting shaft (4) is rotatably mounted on the first connecting rod (202). One end of the connecting shaft (4) is fixedly mounted with a driving bevel gear (5). The driving bevel gear (5) meshes with the driven bevel gear (3). The other end of the connecting shaft (4) is fixedly connected to one end of a third connecting rod (6). The other end of the third connecting rod (6) is hinged to the reciprocating assembly. The fixing frame (1) further includes a first support rod (102) and a second support rod (103). The first support rod (102) is perpendicular to the rectangular frame (101), and the second support rod (103) is perpendicular to the end of the first support rod (102) away from the rectangular frame (101). The second support rod (103) is parallel to the rectangular frame (101). The reciprocating assembly includes a fourth connecting rod (7). The two ends of the fourth connecting rod (7) are respectively hinged to the two third connecting rods (6). A fixing rod (8) is provided in the middle of the fourth connecting rod (7). The fixing rod (8) is hinged to one end of a sixth connecting rod (10) through a fifth connecting rod (9). The other end of the sixth connecting rod (10) passes through the rectangular frame (101) and is hinged to the second support rod (103). The sixth connecting rod (10) can move along the longitudinal direction of the rectangular frame (101). It also includes a drive assembly, which includes a drive motor (11). The output shaft of the drive motor (11) is provided with a motor gear (12). The motor gear (12) meshes with a reduction gear (13). The reduction gear (13) is hinged to the fourth connecting rod (7) through a seventh connecting rod (14). The hinge point between the seventh connecting rod (14) and the reduction gear (13) is offset from the center of the reduction gear (13).

2. The flapping wing structure according to claim 1, characterized in that: The mounting bracket (1) is fixedly connected to the outer shell of the aircraft.

3. An aircraft, characterized in that: It includes two sets of flapping wing structures as described in claim 2, the two sets of flapping wing structures respectively constitute the front wing and rear wing of the aircraft, the drive motor (11) of the flapping wing structure is mounted on a bracket, the bracket is fixedly connected to the shell of the aircraft; the two sets of flapping wing structures are symmetrically arranged on both sides of the bracket.

4. The aircraft according to claim 3, characterized in that: The bracket includes two parallel support plates (15), which are parallel to the rectangular frame (101); two drive motors (11) are fixedly installed between the two support plates (15) and are located at both ends of the support plates (15); the output shafts of the two drive motors (11) face opposite directions and pass through the corresponding support plates (15) respectively, and are fixedly connected to the corresponding motor gears (12); two reduction gears (13) are rotatably installed on the two support plates (15) respectively, and are located on the side of the two support plates (15) away from each other, the center lines of the two reduction gears (13) are on the same straight line, and the center lines of the two reduction gears (13) and the center of the two drive motors (11) are in the same plane.

5. The aircraft according to claim 4, characterized in that: A phase difference adjustment structure is provided between the two sets of flapping wing structures. The phase difference adjustment structure includes a connecting block (16), a placement plate (17), and an attitude sensor (19). Each of the four connecting rods (7) is provided with two connecting ears (18), and the two connecting ears (18) on the two four connecting rods (7) are arranged opposite to each other. There are two connecting blocks (16), and the two connecting blocks (16) are respectively rotatably installed on the two connecting ears (18) of one of the four connecting rods (7). The opposite sides of the two connecting blocks (16) are provided with a sliding groove (1601) that is adapted to the placement plate (17). One end of the placement plate (17) is slidably installed between the two connecting blocks (16), and the other end of the placement plate (17) is hinged to the two connecting ears (18) on the other four connecting rod (7). The attitude sensor (19) is fixedly installed on the placement plate (17).

6. The aircraft according to claim 5, characterized in that: The edge of the attitude sensor (19) is parallel to the edge of the shelf (17). The attitude sensor (19) is used to detect the tilt angle of the shelf (17) relative to the fixing frame (1) to determine the maximum value of the tilt angle and calculate the actual phase difference between the two flapping wing structures based on the maximum value.

7. The aircraft according to claim 6, characterized in that: It also includes a controller, which is electrically connected to the attitude sensor (19) and the drive motor (11); the controller is used to obtain the target phase difference between the two flapping wing structures and calculate the phase difference value to be adjusted according to the actual phase difference; the controller is also used to adjust the rotation speed of at least one of the drive motors (11) according to the phase difference value until the actual phase difference is equal to the target phase difference.

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