A bionic wing flapping mechanism with two degrees of freedom

Abstract

The present invention provides a bionic wing flapping mechanism with two degrees of freedom, which relates to the technical field of unmanned aerial vehicles. The mechanism includes: a base, a first motor, a second motor, a first wire reel, a second wire reel, a support frame, and a gear assembly. The base includes a transverse seat and a longitudinal seat. A first fixing groove and a second fixing groove are provided at two vertex positions of the longitudinal seat that are oppositely arranged. The first motor is installed in the first fixing groove, and the second motor is installed in the second fixing groove. The first wire reel is arranged at the output end of the first motor, and the second wire reel is arranged at the output end of the second motor. Wings are respectively installed at two output ends of the gear assembly, and the two wings are symmetrically arranged. The input ends on both sides of the gear assembly support driving the rotation of the two output ends of the gear assembly. The input end in the middle of the gear assembly supports driving the rotation of the two output ends of the gear assembly. This mechanism drives the gear assembly through a double-motor wire drive to achieve independent control of the flapping and pitching of the wings.

Description

Technical Field

[0001] The present invention relates to the technical field of unmanned aerial vehicles, and particularly to a bionic wing flapping mechanism with two degrees of freedom. Background Art

[0002] A bionic flapping-wing aircraft is a bionic aircraft that generates lift and thrust by imitating the flapping wings of birds, insects, etc. in nature. During the long-term evolution of nature, many flying organisms have evolved the flight mode of flapping wings, and many flying organisms have high flight efficiency, which shows the unique advantages of flapping-wing aircraft compared with rotary-wing and fixed-wing aircraft. Moreover, due to its bionic nature, the flapping-wing aircraft has a very broad application prospect in military reconnaissance and other aspects.

[0003] However, there are many deficiencies in the current bionic flapping-wing aircraft compared with real bionic objects. First of all, birds and insects in nature can freely control and change the movement trajectory of their wings during flight to adapt to different flight requirements. However, the flapping trajectories of the wings of most bionic flapping-wing aircraft are determined by the design of the driving mechanism and can only move along the designed flapping trajectories.

[0004] Secondly, the wing movements of birds and insects in nature are not simply up-and-down flapping. Their wings will also adjust the pitch of the wings during the flapping process to obtain the best aerodynamic characteristics, save flight energy consumption, and improve flight efficiency.

[0005] And most of the current bionic flapping-wing aircraft use a four-bar linkage mechanism to convert the rotational motion output by the motor into the up-and-down reciprocating flapping of the wings. However, the load of the gear set will change with the current flapping position during the movement, making it difficult to control the flapping speed of the wings. Summary of the Invention

[0006] In order to solve the technical problems existing in the prior art, an embodiment of the present invention provides a bionic wing flapping mechanism with two degrees of freedom. The technical solution is as follows:

[0007] A bionic wing flapping mechanism with two degrees of freedom includes:

[0008] A base, the base is arranged in a cross shape, the base includes a horizontal seat and a vertical seat, first fixing grooves and second fixing grooves are arranged at two vertex positions of the vertical seat that are oppositely arranged, and the connection line between the centers of the first fixing groove and the second fixing groove is on the same straight line as the central axis of the frame;

[0009] A first motor and a second motor, the first motor is installed in the first fixing groove, and the second motor is installed in the second fixing groove;

[0010] A first wire reel and a second wire reel, the first wire reel being arranged at the output end of the first motor, and the second wire reel being arranged at the output end of the second motor;

[0011] A support frame arranged along the transverse seat;

[0012] A gear assembly, the gear assembly including two output ends and three input ends, the two output ends of the gear assembly being respectively installed with wings, the two wings being symmetrically arranged, the input ends on both sides of the gear assembly being respectively connected to the first wire reel through a transmission rope system, and the middle input end of the gear assembly being connected to the second wire reel through a transmission rope system;

[0013] The input ends on both sides of the gear assembly support driving the two output ends of the gear assembly to rotate; the middle input end of the gear assembly supports driving the two output ends of the gear assembly to rotate.

[0014] Optionally, the support frame includes: a first vertical plate, a second vertical plate, a third vertical plate, a fourth vertical plate and a mounting beam;

[0015] The first vertical plate, the second vertical plate, the third vertical plate and the fourth vertical plate are arranged on the transverse seat in sequence along the straight line where the transverse seat is located, and through holes are respectively arranged on the top side walls of the first vertical plate, the second vertical plate, the third vertical plate and the fourth vertical plate at the same height;

[0016] A third bearing is arranged in the through hole of the second vertical plate, and a fourth bearing is arranged in the through hole of the third vertical plate;

[0017] The mounting beam is arranged in a U shape, the mounting beam includes two side panels and a cross beam plate, the cross beam plate connects the two side panels, the first vertical plate, the second vertical plate, the third vertical plate and the fourth vertical plate are arranged between the two side panels, and the heights of the through holes on the two side panels are equal to and aligned with the height of the through hole of the first vertical plate;

[0018] A fifth bearing is arranged in the through hole of the side panel on the first vertical plate side, and a sixth bearing is arranged in the through hole of the side panel on the fourth vertical plate side;

[0019] Two through holes are respectively arranged on the cross beam plate, a first bearing is arranged in one through hole on the cross beam plate and is centered on the first vertical plate, and a second bearing is arranged in the other through hole on the cross beam plate and is centered on the fourth vertical plate.

[0020] Optionally, the gear assembly includes:

[0021] The first turntable is installed on the outer wall of the side panel on the side of the first vertical plate, and the first turntable is the input end of the gear assembly;

[0022] The second turntable is installed between the second vertical plate and the third vertical plate, and the second turntable is the input end of the gear assembly;

[0023] The third turntable is installed on the outer wall of the side panel on the side of the fourth vertical plate.

[0024] Optionally, the gear assembly further includes: a first bevel gear, a second bevel gear, and a third bevel gear. The first bevel gear meshes with the second bevel gear, and the second bevel gear meshes with the third bevel gear;

[0025] The first bevel gear is arranged between the side panel on the side of the first vertical plate and the first vertical plate. The first bevel gear is installed on the rod body of the first rotating rod. One end of the first rotating rod is installed in the through hole of the first vertical plate. The rod body of the first rotating rod is installed on the inner ring of the fifth bearing. The other end of the first rotating rod is connected to the first turntable;

[0026] The second bevel gear is installed at one end of the second rotating rod. The rod body of the second rotating rod is installed on the inner ring of the first bearing. The other end of the second rotating rod is the output end of the gear assembly;

[0027] The third bevel gear is installed at one end of the third rotating rod. The rod body of the third rotating rod is successively installed on the inner ring of the third bearing, the center of the second turntable, and the inner ring of the fourth bearing;

[0028] The gear assembly further includes: a fourth bevel gear, a fifth bevel gear, and a sixth bevel gear. The fourth bevel gear meshes with the fifth bevel gear, and the fifth bevel gear meshes with the sixth bevel gear;

[0029] The fourth bevel gear is arranged at the end of the third rotating rod away from the third bevel gear, and the fourth bevel gear is arranged between the third vertical plate and the fourth vertical plate;

[0030] The fifth bevel gear is installed at one end of the fourth rotating rod. The rod body of the fourth rotating rod is installed in the inner ring of the second bearing. The other end of the fourth rotating rod is the output end of the gear assembly;

[0031] The sixth bevel gear is arranged between the side panel on the side of the fourth vertical plate and the fourth vertical plate. The sixth bevel gear is installed on the fifth rotating rod. One end of the fifth rotating rod is installed in the through hole of the fourth vertical plate. The rod body of the fifth rotating rod is installed on the inner ring of the sixth bearing. The other end of the fifth rotating rod is connected to the third turntable.

[0032] Optionally, the support frame further includes: a first support column, a second support column, a third support column, a fourth support column, and a mounting column;

[0033] The mounting column sequentially penetrates through the first vertical plate, the second vertical plate, the third vertical plate, and the fourth vertical plate, and the central axis of the mounting column is horizontally arranged;

[0034] The first support column and the second support column are respectively installed at both ends of the transverse seat and are arranged between the mounting column and the first fixing groove. The first support column is arranged on the side of the first vertical plate, and the second support column is arranged on the side of the fourth vertical plate;

[0035] The third support column and the fourth support column are arranged between the mounting column and the second support column. The positions of the third support column and the fourth support column are aligned with the gap between the second vertical plate and the fourth vertical plate. The line connecting the centers of the gap between the third support column and the fourth support column and the center of the second fixing groove is the center line of the longitudinal seat.

[0036] Optionally, limit rings are respectively arranged at the tops of the first support column and the second support column;

[0037] Limit rings are respectively arranged at both ends of the mounting column.

[0038] Optionally, the first turntable, the second turntable, and the third turntable have the same structure;

[0039] A through hole is opened at the center of the first turntable, and a circle of concave grooves is arranged along the circumference on the circumferential side wall of the first turntable.

[0040] Optionally, the first wire reel and the second wire reel have the same structure. The first wire reel is columnar, and upper wire grooves and lower wire grooves are arranged circumferentially on the side wall of the first wire reel. The upper wire grooves are arranged above the lower wire grooves;

[0041] Horizontal wire threading holes are opened along the diameter direction in the upper wire grooves and the lower wire grooves of the first wire reel, and a vertical wire threading hole is opened on the central axis of the first wire reel. The horizontal wire threading holes of the two first wire reels are respectively communicated with the vertical wire threading hole of the first wire reel;

[0042] Fixing ears are arranged at the top of the first wire reel, and two fixing holes are arranged on the fixing ears.

[0043] Optionally, the transmission rope system includes: a first transmission rope, a second transmission rope, and a third transmission rope;

[0044] The route of the first transmission rope is:

[0045] After the first transmission rope winds around the upper wire groove of the first wire reel in the first direction for at least two turns, one end of the first transmission rope passes through the horizontal wire passing hole and the vertical wire passing hole of the upper wire groove of the first wire reel and is fixed in a fixing hole of the fixing ear of the first wire reel;

[0046] The other end of the first transmission rope is pulled towards the second support column and fits around the mounting column from bottom to top. After the first transmission rope passes around the mounting column, the first transmission rope winds around the first turntable for at least two turns;

[0047] Wherein, the winding direction of the first transmission rope is: winding from the direction of the second motor towards the direction of the first motor;

[0048] After the first transmission rope winds around the first turntable, it sequentially passes around the side walls of the mounting column and the second support column;

[0049] After the first transmission rope passes around the second support column, it winds around the lower wire groove of the first wire reel in the second direction for at least two turns, wherein the first direction and the second direction are opposite;

[0050] After the first transmission rope winds around the lower wire groove of the first wire reel, the first transmission rope sequentially passes through the horizontal wire passing hole and the vertical wire passing hole of the lower wire groove of the first wire reel and is fixed in another fixing hole of the fixing ear of the first wire reel;

[0051] The route of the second transmission rope is:

[0052] After the second transmission rope winds around the upper wire groove of the first wire reel in the first direction for at least two turns, one end of the second transmission rope passes through the horizontal wire passing hole and the vertical wire passing hole of the upper wire groove of the first wire reel and is fixed in a fixing hole of the fixing ear of the first wire reel;

[0053] The other end of the second transmission rope is pulled towards the first support column and fits around the mounting column from bottom to top. After the second transmission rope passes around the mounting column, the second transmission rope winds around the third turntable for at least two turns;

[0054] Wherein, the winding direction of the second transmission rope is: winding from the direction of the second motor towards the direction of the first motor;

[0055] After the second transmission rope winds around the third turntable, it sequentially passes around the side walls of the mounting column and the first support column;

[0056] After the second transmission rope passes around the first support column, it winds around the lower wire groove of the first wire reel in the second direction for at least two turns, wherein the first direction and the second direction are opposite;

[0057] After the second transmission rope is wound around the lower wire groove of the first wire reel, the second transmission rope sequentially passes through the horizontal threading hole and the vertical threading hole of the lower wire groove of the first wire reel and is fixed in another fixing hole of the fixing ear of the first wire reel;

[0058] The line of the third transmission rope is as follows:

[0059] After the third transmission rope is wound around the upper wire groove of the second wire reel in the first direction for at least two turns, one end of the third transmission rope passes through the horizontal threading hole and the vertical threading hole of the upper wire groove of the second wire reel and is fixed in a fixing hole of the fixing ear of the second wire reel;

[0060] The other end of the third transmission rope is pulled towards the gap between the third support column and the fourth support column, and after passing through the gap between the third support column and the fourth support column, the third transmission rope bypasses the mounting column from bottom to top and is wound around the second turntable. The winding direction of the third transmission rope on the second turntable is from the first motor to the second motor;

[0061] After the third transmission rope is wound around the second turntable, the third transmission rope bypasses the mounting column from top to bottom and passes through the gap between the third support column and the fourth support column;

[0062] The third transmission rope is wound around the second wire reel in the second direction for at least two turns, wherein the first direction and the second direction are opposite;

[0063] After the third transmission rope is wound around the lower wire groove of the second wire reel, the third transmission rope sequentially passes through the horizontal threading hole and the vertical threading hole of the lower wire groove of the second wire reel and is fixed in another fixing hole of the fixing ear of the second wire reel.

[0064] Optionally, the wing includes two symmetrically arranged butterfly-shaped wing fins.

[0065] The beneficial effects brought by the technical solution provided by the embodiment of the present invention at least include:

[0066] The drive structure designed in this patent has two degrees of freedom: pitch and flapping. The flapping mechanism of traditional flapping-wing aircraft mainly realizes the degree of freedom of flapping. Moreover, the two degrees of freedom motions realized in this patent can be freely controlled. The trajectories of flapping and pitch can be freely controlled, with higher flexibility. For the gear-linkage mechanism adopted by the drive structures of the vast majority of flapping-wing aircraft, the motion trajectory of the wings depends on the mechanical design parameters of the gear-linkage. After the sizes of the gears and linkages are fixed, the motion trajectory of the wings is also fixed accordingly and cannot be freely controlled. Only the flapping speed of the wings can be controlled. In this patent, through the FOC control of the motor, not only can the flapping and pitch speeds of the wings be controlled, but also the flapping and pitch trajectories of the wings can be freely adjusted. In addition, the method for realizing two degrees of freedom in this patent can reduce the inertia at the execution end. The two motors are both horizontally placed on the platform base and only rotate without displacement along with the motion of the flapping mechanism. Compared with the traditional scheme where two motors are respectively placed on the motion axes of two degrees of freedom, in the design scheme of this patent, during the motion of the flapping mechanism, the main inertial force comes from the wings, and the inertial forces generated by components such as transmission ropes and gears with relatively light masses are relatively small. Since the motors are horizontally placed, the inertial force generated by the motor rotors on the Z-axis can be basically ignored, so that the measurement data is more accurate when measuring the lift force of the wings on the Z-axis. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for description in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0068] Figure 1 is an isometric view of the first perspective of a two-degree-of-freedom bionic wing flapping mechanism provided by an embodiment of the present invention;

[0069] Figure 2 is a top view of a two-degree-of-freedom bionic wing flapping mechanism provided by an embodiment of the present invention;

[0070] Figure 3 is a top view of a partial structure of a two-degree-of-freedom bionic wing flapping mechanism provided by an embodiment of the present invention;

[0071] Figure 4 is a top view of the first perspective of a partial structure of a two-degree-of-freedom bionic wing flapping mechanism provided by an embodiment of the present invention;

[0072] Figure 5 is a top view of the second perspective of a partial structure of a two-degree-of-freedom bionic wing flapping mechanism provided by an embodiment of the present invention;

[0073] Figure 6It is an axonometric view of the first perspective of the support frame of a double-degree-of-freedom bionic wing flapping mechanism provided by an embodiment of the present invention;

[0074] Figure 7 It is an axonometric view of the second perspective of the support frame of a double-degree-of-freedom bionic wing flapping mechanism provided by an embodiment of the present invention;

[0075] Figure 8 It is an axonometric view of the cross-sectional view of the first wire reel or the second wire reel of a double-degree-of-freedom bionic wing flapping mechanism provided by an embodiment of the present invention;

[0076] Figure 9 It is a structural schematic diagram of the base of a double-degree-of-freedom bionic wing flapping mechanism provided by an embodiment of the present invention;

[0077] Figure 10 It is a schematic diagram of the upper surface of one wing of a double-degree-of-freedom bionic wing flapping mechanism provided by an embodiment of the present invention;

[0078] Figure 11 It is a schematic diagram of the lower surface of one wing of a double-degree-of-freedom bionic wing flapping mechanism provided by an embodiment of the present invention;

[0079] Figure 12 It is a structural schematic diagram of two wings of a double-degree-of-freedom bionic wing flapping mechanism provided by an embodiment of the present invention;

[0080] Figure 13 It is a marked diagram of the rotation directions of each component when the first motor of a double-degree-of-freedom bionic wing flapping mechanism rotates clockwise;

[0081] Figure 14 It is a marked diagram of the rotation directions of each component when the second motor of a double-degree-of-freedom bionic wing flapping mechanism rotates clockwise.

[0082] Reference numerals:

[0083] 1. Base; 11. Horizontal base; 12. Vertical base; 13. First fixing groove; 14. Second fixing groove; 2. First motor; 3. Second motor; 4. First wire reel; 5. Second wire reel; 451. Upper wire groove; 452. Lower wire groove; 453. Horizontal wire passing hole; 454. Vertical wire passing hole; 455. Fixing ear; 6. Support frame; 61. First vertical plate; 62. Second vertical plate; 63. Third vertical plate; 64. Fourth vertical plate; 65. Installation beam; 651. Side panel; 652. Cross beam panel; 66. First support column; 67. Second support column; 68. Third support column; 69. Fourth support column; 6100. Installation column; 6105. First bearing; 6106. Second bearing; 6103. Third bearing; 6104. Fourth bearing; 6101. Fifth bearing; 6102. Sixth bearing; 7. Gear assembly; 71. First turntable; 72. Second turntable; 73. Third turntable; 74. First bevel gear; 75. Second bevel gear; 76. Third bevel gear; 77. Fourth bevel gear; 78. Fifth bevel gear; 79. Sixth bevel gear; 701. First rotating rod; 702. Second rotating rod; 703. Third rotating rod; 704. Fourth rotating rod; 705. Fifth rotating rod; 8. Transmission rope system; 81. First transmission rope; 82. Second transmission rope; 83. Third transmission rope; 9. Wing. Detailed implementation manner

[0084] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the described embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0085] Unless otherwise defined, the technical terms or scientific terms used in the present invention shall have the ordinary meanings understood by those of ordinary skill in the art to which the present invention pertains. The "first", "second", and similar terms used in the present invention do not denote any order, quantity, or importance, but are only used to distinguish different components. Similarly, terms such as "a", "an", or "the" do not denote a quantity limitation, but mean that there is at least one. The terms "comprising" or "including" and the like mean that the elements or items appearing before the term cover the elements or items listed after the term and their equivalents, without excluding other elements or items. The terms "connected" or "coupled" and the like are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect.

[0086] It should be noted that the terms "upper", "lower", "left", "right", "front", "rear", etc. used in the present invention are only for indicating relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0087] The present invention mainly aims at the defects of existing bionic flapping-wing aircraft, such as having few degrees of freedom in the flapping mechanism, poor bionic performance, fixed trajectories that cannot be flexibly adjusted, and large load changes in the commonly used four-bar linkage mechanism, making it difficult to control. A bionic wing flapping mechanism with two degrees of freedom is proposed. Through the double-motor rope drive differential joint mechanism, the present invention can realize independent control of the flapping and pitching of the wings. And in this solution, the load only has a slight change due to the gravity of the differential joint and the wings at each flapping angle. Combining the FOC control of the motors to precisely control the positions of the two motors can achieve the motion trajectories of arbitrary flapping and pitching angles of the bionic wings. Since the motors are horizontally installed, the mass of the differential joint is small, and the rotation amplitude of the motors is not large, the overall moment of inertia is very small, and the inertial force generated in the Z-axis direction is small. When a force sensor is installed for measurement, the interference of additional inertial forces can be excluded, and a more accurate wing lift force can be measured.

[0088] As Figures 1 to 10 shown, the present invention specifically provides a bionic wing flapping mechanism with two degrees of freedom in one aspect, including: a base 1, a first motor 2, a second motor 3, a first wire reel 4, a second wire reel 5, a support frame 6, and a gear assembly 7.

[0089] The base 1 is arranged in a cross shape. The base 1 includes a horizontal seat 11 and a vertical seat 12. First fixing grooves 13 and 14 are arranged at two vertex positions of the vertical seat 12 that are oppositely arranged. The connection line between the centers of the first fixing groove 13 and the second fixing groove 14 is on the same straight line as the central axis of the frame. The first motor 2 is installed in the first fixing groove 13, and the second motor 3 is installed in the second fixing groove 14. The first wire reel 4 is arranged at the output end of the first motor 2, and the second wire reel 5 is arranged at the output end of the second motor 3. The support frame 6 is arranged along the horizontal seat 11. The gear assembly 7 includes two output ends and three input ends. Wings 9 are respectively installed at the two output ends of the gear assembly 7, and the two wings 9 are symmetrically arranged. The input ends on both sides of the gear assembly 7 are respectively connected to the first wire reel 4 through a transmission rope system 8, and the middle input end of the gear assembly 7 is connected to the second wire reel 5 through the transmission rope system 8. The input ends on both sides of the gear assembly 7 support driving the two output ends of the gear assembly 7 to rotate. The middle input end of the gear assembly 7 supports driving the two output ends of the gear assembly 7 to rotate.

[0090] In a specific embodiment, the base 1 is formed by machining a housing. The base 1 is symmetrically arranged in a cross shape and includes a transverse seat 11 and a longitudinal seat 12. The length of the longitudinal seat 12 is longer than that of the transverse seat 11. Column-shaped concave first fixing grooves 13 and second fixing grooves 14 are provided at opposite ends of the longitudinal seat 12. The first fixing groove 13 is used to install the first motor 2, and the second fixing groove 14 is used to install the second fixing groove 14. Both the first motor 2 and the second motor 3 are brushless motors with magnetic encoders. In addition, the first motor 2 and the second motor 3 are controlled by a motor FOC microcontroller. The motor FOC microcontroller is electrically connected to the magnetic encoders and three-phase input interfaces of the first motor 2 and the second motor 3, and the FOC microcontroller is equipped with a Zigbee communication module, which can be remotely controlled by a host computer. The operating principles and control principles of the relevant motors are prior art. The first motor 2 and the second motor 3 can be fixed in the first fixing groove 13 and the second fixing groove 14 by bolt fixing, which is prior art.

[0091] In a specific embodiment, the support frame 6 includes: a first vertical plate 61, a second vertical plate 62, a third vertical plate 63, a fourth vertical plate 64, and a mounting beam 65;

[0092] The first vertical plate 61, the second vertical plate 62, the third vertical plate 63, and the fourth vertical plate 64 are arranged in sequence along the straight line where the transverse seat 11 is located on the transverse seat 11. Through holes are provided on the top side walls of the first vertical plate 61, the second vertical plate 62, the third vertical plate 63, and the fourth vertical plate 64 at the same height;

[0093] A third bearing 6103 is arranged in the through hole of the second vertical plate 62, and a fourth bearing 6104 is arranged in the through hole of the third vertical plate 63;

[0094] The mounting beam 65 is arranged in a U shape and includes two side panels 651 and a cross beam panel 652. The cross beam panel 652 connects the two side panels 651. The first vertical plate 61, the second vertical plate 62, the third vertical plate 63, and the fourth vertical plate 64 are arranged between the two side panels 651. The heights of the through holes on the two side panels 651 are equal to and aligned with the height of the through hole of the first vertical plate 61;

[0095] A fifth bearing 6101 is arranged in the through hole of the side panel 651 on the side of the first vertical plate 61, and a sixth bearing 6102 is arranged in the through hole of the side panel 651 on the side of the fourth vertical plate 64;

[0096] Two through holes are respectively provided on the cross beam plate. A first bearing 6105 is arranged in one through hole on the cross beam plate and is centered with the first vertical plate 61, and a first bearing 6106 is arranged in the other through hole on the cross beam plate and is centered with the fourth vertical plate 64.

[0097] In a specific embodiment, the gear assembly 7 includes: a first turntable 71, a second turntable 72, a third turntable 73, a fourth bevel gear 77, a fifth bevel gear 78 and a sixth bevel gear 79.

[0098] The first turntable 71 is installed on the outer wall of the side panel 651 on the side of the first vertical plate 61, and the first turntable 71 is the input end of the gear assembly 7; the second turntable 72 is installed between the second vertical plate 62 and the third vertical plate 63, and the second turntable 72 is the input end of the gear assembly 7; the third turntable is installed on the outer wall of the side panel 651 on the side of the fourth vertical plate 64.

[0099] The first bevel gear 74 meshes with the second bevel gear 75, and the second bevel gear 75 meshes with the third bevel gear 76; the first bevel gear 74 is arranged between the side panel 651 on the side of the first vertical plate 61 and the first vertical plate 61, the first bevel gear 74 is installed on the rod body of the first rotating rod 705, one end of the first rotating rod 705 is installed in the through hole of the first vertical plate 61, the rod body of the first rotating rod 705 is installed on the inner ring of the fifth bearing 6101, and the other end of the first rotating rod 705 is connected to the first turntable 71;

[0100] The second bevel gear 75 is installed at one end of the second rotating rod, the rod body of the second rotating rod is installed on the inner ring of the first bearing 6105, and the other end of the second rotating rod is the output end of the gear assembly 7;

[0101] The third bevel gear 76 is installed at one end of the third rotating rod, and the rod body of the third rotating rod is successively installed with the inner ring of the third bearing 6103, the center of the second turntable 72 and the inner ring of the fourth bearing 6104;

[0102] The gear assembly 7 further includes: a fourth bevel gear 77, a fifth bevel gear 78 and a sixth bevel gear 79, the fourth bevel gear 77 meshes with the fifth bevel gear 78, and the fifth bevel gear 78 meshes with the sixth bevel gear 79;

[0103] The fourth bevel gear 77 is arranged at the end of the third rotating rod far from the third bevel gear 76, and the fourth bevel gear 77 is arranged between the third vertical plate 63 and the fourth vertical plate 64;

[0104] The fifth bevel gear 78 is installed at one end of the fourth rotating rod. The rod body of the fourth rotating rod is installed in the inner ring of the first bearing 6106. The other end of the fourth rotating rod is the output end of the gear assembly 7.

[0105] The sixth bevel gear 79 is arranged between the side panel 651 on the side of the fourth vertical plate 64 and the fourth vertical plate 64. The sixth bevel gear 79 is installed on the fifth rotating rod. One end of the fifth rotating rod is installed in the through hole of the fourth vertical plate 64. The rod body of the fifth rotating rod is installed on the inner ring of the sixth bearing. The other end of the fifth rotating rod is connected to the third turntable 73.

[0106] The first bevel gear 74, the second bevel gear 75 and the third bevel gear 76 in the gear assembly 7 form a structure in which three gears mesh with each other. The fourth bevel gear 77, the fifth bevel gear 78 and the sixth bevel gear 79 in the gear assembly 7 form a structure in which three gears mesh with each other. This structure is a prior art.

[0107] In a specific embodiment, the support frame 6 further includes: a first support column 66, a second support column 67, a third support column 68, a fourth support column 69 and a mounting column 6100;

[0108] The mounting column 6100 sequentially passes through the first vertical plate 61, the second vertical plate 62, the third vertical plate 63 and the fourth vertical plate 64. The central axis of the mounting column 6100 is horizontally arranged;

[0109] The first support column 66 and the second support column 67 are respectively installed at both ends of the transverse seat 11 and are arranged between the mounting column 6100 and the first fixing groove 13. The first support column 66 is arranged on the side of the first vertical plate 61, and the second support column 67 is arranged on the side of the fourth vertical plate 64;

[0110] The third support column 68 and the fourth support column 69 are arranged between the mounting column 6100 and the second support column. The positions of the third support column 68 and the fourth support column are aligned with the gap between the second vertical plate 62 and the fourth vertical plate 64. The line connecting the centers of the gaps between the third support column 68 and the fourth support column 69 is the center line of the longitudinal seat 12.

[0111] In a specific embodiment, limit rings are respectively arranged at the tops of the first support column 66 and the second support column 67;

[0112] Limit rings are respectively arranged at both ends of the mounting column 6100.

[0113] Among them, the structures of the first turntable 71, the second turntable 72, and the third turntable 73 are the same;

[0114] A through hole is opened at the center of the first turntable 71, and a circle of concave grooves is arranged along the circumferential direction on the circumferential side wall of the first turntable 71.

[0115] Among them, the structures of the first wire reel 4 and the second wire reel 5 are the same. The first wire reel 4 is arranged in a columnar shape, and an upper wire groove 451 and a lower wire groove 452 are arranged circumferentially on the side wall of the first wire reel 4. The upper wire groove 451 is arranged above the lower wire groove 452;

[0116] The upper wire groove 451 and the lower wire groove 452 of the first wire reel 4 are provided with transverse wire passing holes 453 in the diameter direction, and a longitudinal wire passing hole 454 is opened on the central axis of the first wire reel 4. The transverse wire passing holes 453 of the two first wire reels 4 are respectively communicated with the longitudinal wire passing hole of the first wire reel 4;

[0117] A fixing ear 455 is arranged on the top of the first wire reel 4, and two fixing holes are arranged on the fixing ear 455.

[0118] Specifically, one implementation of the transmission rope system 8 includes: a first transmission rope 81, a second transmission rope 82, and a third transmission rope 83;

[0119] The route of the first transmission rope 81 is:

[0120] After the first transmission rope 81 winds around the upper wire groove 451 of the first wire reel 4 in the first direction for at least two turns, one end of the first transmission rope 81 passes through the transverse wire passing hole and the longitudinal wire passing hole 454 of the upper wire groove 451 of the first wire reel 4 and is fixed in one of the fixing holes of the fixing ear 455 of the first wire reel 4;

[0121] The other end of the first transmission rope 81 is pulled towards the second support column 67 and bypasses the mounting column 6100 from bottom to top. After the first transmission rope 81 bypasses the mounting column 6100, the first transmission rope 81 winds around the first turntable 71 for at least two turns;

[0122] Among them, the winding direction of the first transmission rope 81 is: winding from the direction of the second motor 3 towards the direction of the first motor 2;

[0123] After the first transmission rope 81 winds around the first turntable 71, it successively bypasses the side walls of the mounting column 6100 and the second support column 67;

[0124] The first transmission rope 81 bypasses the second support column 67 and then winds around the lower wire groove 452 of the first wire reel 4 at least two turns in a second direction, where the first direction and the second direction are opposite;

[0125] After the first transmission rope 81 winds around the lower wire groove 452 of the first wire reel 4, the first transmission rope sequentially passes through the horizontal threading hole and the vertical threading hole of the lower wire groove 452 of the first wire reel 4 and is fixed in another fixing hole of the fixing ear 455 of the first wire reel 4;

[0126] The route of the second transmission rope 82 is as follows:

[0127] After the second transmission rope 82 winds around the upper wire groove 451 of the first wire reel 4 at least two turns in the first direction, one end of the second transmission rope 82 passes through the horizontal threading hole and the vertical threading hole 454 of the upper wire groove 451 of the first wire reel 4 and is fixed in one fixing hole of the fixing ear 455 of the first wire reel 4;

[0128] The other end of the second transmission rope 82 is pulled towards the first support column 66 and fits around the mounting column 6100 from bottom to top. After the second transmission rope 82 bypasses the mounting column 6100, the second transmission rope 82 winds around the third turntable 73 at least two turns;

[0129] Among them, the winding direction of the second transmission rope 82 is: winding from the direction of the second motor 3 towards the direction of the first motor 2;

[0130] After the second transmission rope 82 winds around the first turntable 71, it sequentially bypasses the mounting column 6100 and the side walls of the first support column 66;

[0131] The second transmission rope 82 bypasses the first support column 66 and then winds around the lower wire groove 452 of the first wire reel 4 at least two turns in a second direction, where the first direction and the second direction are opposite;

[0132] After the second transmission rope 82 winds around the lower wire groove 452 of the first wire reel 4, the first transmission rope sequentially passes through the horizontal threading hole and the vertical threading hole of the lower wire groove 452 of the first wire reel 4 and is fixed in another fixing hole of the fixing ear 455 of the first wire reel 4;

[0133] The route of the third transmission rope 83 is as follows:

[0134] After the third transmission rope 83 winds around the upper wire groove 451 of the second wire reel 5 in the first direction for at least two turns, one end of the third transmission rope 83 passes through the horizontal wire passing hole and the vertical wire passing hole 454 of the upper wire groove 451 of the second wire reel 5 and is fixed in a fixing hole of the fixing ear 455 of the second wire reel 5;

[0135] The other end of the third transmission rope 83 is pulled towards the gap between the third support column 68 and the fourth support column 69, and after passing through the gap between the third support column 68 and the fourth support column 69, the third transmission rope 83 winds around the second turntable 72 from bottom to top after winding around the mounting column 6100. The winding direction of the third transmission rope 83 on the second turntable 72 is from the first motor 2 to the second motor 3;

[0136] After the third transmission rope 83 winds around the second turntable, the third transmission rope 83 winds around the mounting column 6100 from top to bottom and passes through the gap between the third support column 68 and the fourth support column 69;

[0137] The third transmission rope 83 winds around the second wire reel 5 in the second direction for at least two turns, wherein the first direction and the second direction are opposite;

[0138] After the third transmission rope 83 winds around the lower wire groove 452 of the second wire reel 5, the third transmission rope sequentially passes through the horizontal wire passing hole of the lower wire groove 452 of the second wire reel 5 and the vertical wire passing hole of the second wire reel 5 and is fixed in another fixing hole of the fixing ear 455 of the second wire reel 5.

[0139] In a specific embodiment, the wing 9 includes two symmetrically arranged butterfly-shaped wing fins, as Figures 10 - 12 shown. For the structure of one wing 9, the wing 9 includes: a butterfly-shaped fin, a mounting plate, a connecting shaft. One end of the connecting shaft is mounted on the second rotating rod or the fourth rotating rod. The second rotating rod and the fourth rotating rod drive the corresponding wing 9 to rotate (flap up and down). The other end of the connecting shaft is connected to the mounting plate. The butterfly-shaped fin is mounted on the mounting plate. The upper surface of the butterfly-shaped fin is smoothly arranged, and the lower surface of the butterfly-shaped fin is arranged with a butterfly texture.

[0140] The movement principle of this mechanism is:

[0141] When working, the PC-side host computer needs to use Zigbee to remotely send signals, import the flap and pitch angle trajectories, and then send a start instruction. Only then can the FOC microcontroller control the two motors (the first motor 2 and the second motor 3). The microcontroller will decompose the flap and pitch angles of the wing into the rotational movements of the two motors, and then control the motors to move along a certain angular trajectory.

[0142] The realization of wing pitching and flapping is achieved by two differential gear sets (gear assembly 7). The specific content is as follows:

[0143] As Figure 13 and 14 shown, the clockwise and counterclockwise directions are marked and explained in the figure for explaining the clockwise and counterclockwise directions in this paragraph. If we want the wing to perform pure pitching motion, we need to control the first motor 2 and the second motor 3 to rotate at the same speed and in the same direction. For example, when the first motor 2 and the second motor 3 rotate clockwise simultaneously (the first direction is the clockwise direction and the second direction is the counterclockwise direction), the upper transmission ropes of the first wire reel 4 and the second wire reel 5 will be sent out from the motor turntables, and the lower transmission ropes of the first wire reel 4 and the second wire reel 5 will be retracted, so that the first turntable 71, the second turntable 72, and the third turntable 73 on the differential joint all rotate, and the rotation follows the following rules:

[0144] When the first wire reel 4 rotates clockwise in the direction shown in the figure, the first turntable 71 rotates clockwise. The first turntable drives the first bevel gear 74 to rotate in the same direction. The first bevel gear 74 drives the second bevel gear 75 meshing with it to rotate counterclockwise relatively. The second rotating rod rotates counterclockwise following the second bevel gear 75. The third turntable 73 rotates clockwise. The third turntable 73 drives the sixth bevel gear 79 to rotate in the same direction. The sixth bevel gear 79 drives the fifth bevel gear 78 meshing with it to rotate relatively. The fourth rotating rod rotates clockwise following the fifth bevel gear 78. That is: the second rotating rod rotates counterclockwise, and the fourth rotating rod rotates clockwise.

[0145] When the second wire reel 5 rotates clockwise in the direction shown in the figure, the second turntable 72 rotates clockwise. The third bevel gear 76 and the fourth bevel gear 77 rotate clockwise in the same direction. The third bevel gear 76 drives the second bevel gear 75 to rotate clockwise. The fourth bevel gear 77 drives the fifth bevel gear 78 to rotate counterclockwise. That is: the second rotating rod rotates clockwise, and the fourth rotating rod rotates counterclockwise.

[0146] In this embodiment, it does not rotate around its own central axis itself, that is, a motion with an increasing pitching angle and an unchanged flapping angle occurs (because the clockwise and counterclockwise directions cancel each other out, resulting in the wing 9 not flapping).

[0147] To make the wing perform pure flapping motion, we need to control the first motor 2 and the second motor 3 to rotate at the same speed and in opposite directions.

[0148] In the flapping platform designed in this patent, since the sizes of the front and rear motor turntables are the same, and the sizes of the three wire winding turntables on the differential joint are also the same, its pitching angle is:

[0149]

[0150] The flapping angle is:

[0151]

[0152] Through the above formula, the movements of the first motor 2 and the second motor 3 can be converted into the pitching and flapping movements of the wings. By precisely controlling the positions of the motors through the FOC controller, precise control of the wing flapping and pitching angles can be achieved.

[0153] The following points need to be explained:

[0154] (1) The accompanying drawings of the embodiments of the present invention only relate to the structures involved in the embodiments of the present invention, and other structures can refer to the general designs.

[0155] (2) For clarity, in the accompanying drawings used to describe the embodiments of the present invention, the thicknesses of layers or regions are enlarged or reduced, that is, these drawings are not drawn to actual scale. It can be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" or "under" another element, the element can be "directly" on or under the other element or there can be intermediate elements.

[0156] (3) Without conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other to obtain new embodiments.

[0157] The above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. The protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A bionic wing flapping mechanism with two degrees of freedom, characterized in that, Comprising: A base, the base is arranged in a cross shape, the base includes a horizontal seat and a vertical seat, first fixing grooves and second fixing grooves are arranged at two vertex positions of the vertical seat that are relatively arranged, and the connection line between the centers of the first fixing groove and the second fixing groove is on the same straight line as the central axis of the frame; A first motor and a second motor, the first motor is installed in the first fixing groove, and the second motor is installed in the second fixing groove; A first wire reel and a second wire reel, the first wire reel is arranged at the output end of the first motor, and the second wire reel is arranged at the output end of the second motor; A support frame, the support frame is arranged along the horizontal seat; A gear assembly, the gear assembly includes two output ends and three input ends, the two output ends of the gear assembly are respectively installed with wings, the two wings are symmetrically arranged, the input ends on both sides of the gear assembly are respectively connected to the first wire reel through a transmission rope system, and the middle input end of the gear assembly is connected to the second wire reel through a transmission rope system; The input ends on both sides of the gear assembly support driving the two output ends of the gear assembly to rotate; the middle input end of the gear assembly supports driving the two output ends of the gear assembly to rotate; The support frame includes: a first vertical plate, a second vertical plate, a third vertical plate, a fourth vertical plate and a mounting beam; The mounting beam is arranged in a U shape, the mounting beam includes two side panels and a cross beam plate, and the cross beam plate connects the two side panels; The two output ends are arranged as rod-shaped structures, extending out from the through holes opened on the cross beam plate, one end is connected to the gear assembly, the other end passes through the connecting shaft of the wing, and the two side panels are respectively hinged to the first vertical plate and the fourth vertical plate; The pitch angle of the wing is: The flapping angle of the wing is:

2. The double-degree-of-freedom bionic wing flapping mechanism according to claim 1, characterized in that The first vertical plate, the second vertical plate, the third vertical plate and the fourth vertical plate are arranged on the horizontal seat in sequence along the straight line where the horizontal seat is located, and through holes at the same height are respectively arranged on the top side walls of the first vertical plate, the second vertical plate, the third vertical plate and the fourth vertical plate; A third bearing is arranged in the through hole of the second vertical plate, and a fourth bearing is arranged in the through hole of the third vertical plate; The first vertical plate, the second vertical plate, the third vertical plate and the fourth vertical plate are arranged between the two side panels, and the heights of the through holes on the two side panels are equal to and aligned with the height of the through hole of the first vertical plate; A fifth bearing is arranged in the through hole of the side panel on the first vertical plate side, and a sixth bearing is arranged in the through hole of the side panel on the fourth vertical plate side; Two through holes are respectively arranged on the cross beam plate, a first bearing is arranged in one through hole on the cross beam plate and is centered on the first vertical plate, and a second bearing is arranged in the other through hole on the cross beam plate and is centered on the fourth vertical plate.

3. The double-degree-of-freedom bionic wing flapping mechanism according to claim 2, characterized in that The gear assembly includes: A first turntable, the first turntable is installed on the outer side wall of the side panel on the first vertical plate side, and the first turntable is the input end of the gear assembly; A second turntable, the second turntable is installed between the second vertical plate and the third vertical plate, and the second turntable is the input end of the gear assembly; A third turntable, the third turntable is installed on the outer wall of the side panel on the fourth vertical plate side.

4. The double-degree-of-freedom bionic wing flapping mechanism according to claim 3, wherein, The gear assembly further includes: a first bevel gear, a second bevel gear, and a third bevel gear. The first bevel gear meshes with the second bevel gear, and the second bevel gear meshes with the third bevel gear; The first bevel gear is disposed between the side panel on the side of the first vertical plate and the first vertical plate. The first bevel gear is mounted on the rod body of a first rotating rod. One end of the first rotating rod is mounted in the through hole of the first vertical plate. The rod body of the first rotating rod is mounted on the inner ring of a fifth bearing. The other end of the first rotating rod is connected to the first turntable; The second bevel gear is mounted on one end of a second rotating rod. The rod body of the second rotating rod is mounted on the inner ring of a first bearing. The other end of the second rotating rod is the output end of the gear assembly; The third bevel gear is mounted on one end of a third rotating rod. The rod body of the third rotating rod is successively mounted on the inner ring of a third bearing, the center of the second turntable, and the inner ring of a fourth bearing; The gear assembly further includes: a fourth bevel gear, a fifth bevel gear, and a sixth bevel gear. The fourth bevel gear meshes with the fifth bevel gear, and the fifth bevel gear meshes with the sixth bevel gear; The fourth bevel gear is disposed at the end of the third rotating rod away from the third bevel gear. The fourth bevel gear is disposed between the third vertical plate and the fourth vertical plate; The fifth bevel gear is mounted on one end of a fourth rotating rod. The rod body of the fourth rotating rod is mounted in the inner ring of the second bearing. The other end of the fourth rotating rod is the output end of the gear assembly; The sixth bevel gear is disposed between the side panel on the side of the fourth vertical plate and the fourth vertical plate. The sixth bevel gear is mounted on a fifth rotating rod. One end of the fifth rotating rod is mounted in the through hole of the fourth vertical plate. The rod body of the fifth rotating rod is mounted on the inner ring of a sixth bearing. The other end of the fifth rotating rod is connected to the third turntable.

5. The double-degree-of-freedom bionic wing flapping mechanism according to claim 4, characterized in that The support frame further includes: a first support column, a second support column, a third support column, a fourth support column, and a mounting column; The mounting column successively penetrates through the first vertical plate, the second vertical plate, the third vertical plate, and the fourth vertical plate. The central axis of the mounting column is horizontally arranged; The first support column and the second support column are respectively mounted at both ends of the transverse seat and are disposed between the mounting column and the first fixing groove. The first support column is disposed on the side of the first vertical plate, and the second support column is disposed on the side of the fourth vertical plate; The third support column and the fourth support column are disposed between the mounting column and the second support column. The positions of the third support column and the fourth support column align with the gap between the second vertical plate and the fourth vertical plate. The connection line between the center of the gap between the third support column and the fourth support column and the center of the second fixing groove is the center line of the longitudinal seat.

6. The double-degree-of-freedom bionic wing flapping mechanism according to claim 5, characterized in that, Limit rings are respectively provided at the tops of the first support column and the second support column; Limit rings are respectively provided at both ends of the mounting column.

7. The double-degree-of-freedom bionic wing flapping mechanism according to claim 6, characterized in that The structures of the first turntable, the second turntable, and the third turntable are the same; A through hole is opened at the center of the first turntable. A circle of concave grooves is provided along the circumferential direction on the circumferential side wall of the first turntable.

8. The double-degree-of-freedom bionic wing flapping mechanism according to claim 7, wherein the first wire reel and the second wire reel have the same structure. The first wire reel is columnar, and an upper wire groove and a lower wire groove are circumferentially arranged on the side wall of the first wire reel. The upper wire groove is arranged above the lower wire groove. The upper wire groove and the lower wire groove of the first wire reel are provided with transverse wire holes along the diameter direction, and a longitudinal wire hole is provided on the central axis of the first wire reel. The transverse wire holes of the two first wire reels are respectively communicated with the longitudinal wire hole of the first wire reel. A fixing ear is arranged on the top of the first wire reel, and two fixing holes are arranged on the fixing ear.

9. The double-degree-of-freedom bionic wing flapping mechanism according to claim 8, characterized in that, The transmission rope system includes: a first transmission rope, a second transmission rope, and a third transmission rope. The route of the first transmission rope is as follows: After the first transmission rope winds around the upper wire groove of the first wire reel in the first direction for at least two turns, one end of the first transmission rope passes through the transverse wire hole and the longitudinal wire hole of the upper wire groove of the first wire reel and is fixed in one of the fixing holes of the fixing ear of the first wire reel. The other end of the first transmission rope is pulled towards the second support column and fits around the mounting column from bottom to top. After the first transmission rope passes around the mounting column, the first transmission rope winds around the first turntable for at least two turns. Wherein, the winding direction of the first transmission rope is: winding from the direction of the second motor towards the direction of the first motor. After the first transmission rope winds around the first turntable, it successively passes around the side walls of the mounting column and the second support column. After the first transmission rope passes around the second support column, it winds around the lower wire groove of the first wire reel in the second direction for at least two turns, wherein the first direction and the second direction are opposite. After the first transmission rope winds around the lower wire groove of the first wire reel, the first transmission rope successively passes through the transverse wire hole and the longitudinal wire hole of the lower wire groove of the first wire reel and is fixed in the other fixing hole of the fixing ear of the first wire reel. The route of the second transmission rope is as follows: After the second transmission rope winds around the upper wire groove of the first wire reel in the first direction for at least two turns, one end of the second transmission rope passes through the transverse wire hole and the longitudinal wire hole of the upper wire groove of the first wire reel and is fixed in one of the fixing holes of the fixing ear of the first wire reel. The other end of the second transmission rope is pulled towards the first support column and fits around the mounting column from bottom to top. After the second transmission rope passes around the mounting column, the second transmission rope winds around the third turntable for at least two turns. Wherein, the winding direction of the second transmission rope is: winding from the direction of the second motor towards the direction of the first motor. After the second transmission rope winds around the third turntable, it successively passes around the side walls of the mounting column and the first support column. After the second transmission rope passes around the first support column, it winds around the lower wire groove of the first wire reel in the second direction for at least two turns, wherein the first direction and the second direction are opposite. After the second transmission rope winds around the lower wire groove of the first wire reel, the second transmission rope sequentially passes through the horizontal threading hole and the vertical threading hole of the lower wire groove of the first wire reel and is fixed in another fixing hole of the fixing ear of the first wire reel; The route of the third transmission rope is: After the third transmission rope winds around the upper wire groove of the second wire reel in the first direction for at least two turns, one end of the third transmission rope passes through the horizontal threading hole and the vertical threading hole of the upper wire groove of the second wire reel and is fixed in a fixing hole of the fixing ear of the second wire reel; The other end of the third transmission rope is pulled towards the gap between the third support column and the fourth support column, and after passing through the gap between the third support column and the fourth support column, the third transmission rope winds around the second turntable from bottom to top around the mounting column, and the winding direction of the third transmission rope on the second turntable is from the first motor to the second motor; After the third transmission rope winds around the second turntable, the third transmission rope winds around the mounting column from top to bottom and passes through the gap between the third support column and the fourth support column; The third transmission rope winds around the second wire reel in the second direction for at least two turns, wherein the first direction and the second direction are opposite; After the third transmission rope winds around the lower wire groove of the second wire reel, the third transmission rope sequentially passes through the horizontal threading hole of the lower wire groove of the second wire reel and the vertical threading hole of the second wire reel and is fixed in another fixing hole of the fixing ear of the second wire reel.

10. The double-degree-of-freedom bionic wing flapping mechanism according to claim 1, characterized in that, The wing includes two symmetrically arranged butterfly-shaped wing fins.

Images