A bionic hummingbird flapping-wing aircraft with ultralight structure and control system

Abstract

The present invention discloses a bionic hummingbird flapping-wing aircraft with an ultralight structure and a control system, comprising a frame and a wing system fixed on the frame, a power transmission system, a pitch servo control system, a roll servo control system and a micro-integrated flexible folding circuit board system; the frame comprises an upper frame and a lower frame, wherein the upper frame comprises an upper bottom plate pulley frame, a bottom plate connecting member and a lower bottom plate pulley frame; the lower frame comprises a suspension, a front support frame, a rear support frame and a base; the suspension is fixed to the lower surface of the lower bottom plate pulley frame through a first hanging ear; the wing system consists of a pair of left and right wings, each wing comprises a wing pulley, a wing rod and a wing root rod, a wing membrane is fixed on the wing rod and the wing root rod, and the wing membrane is provided with a wing membrane hole at the wing root; the power transmission system realizes the flapping motion of a pair of wings by driving the reciprocating rotation of the wing pulley. By using the present invention, flapping-wing flight can be realized without an external power cord and only relying on battery power supply.

Description

Technical Field

[0001] The invention belongs to the technical field of aircraft, and in particular relates to a bionic hummingbird flapping-wing aircraft with an ultralight structure and a control system. Background Art

[0002] Bionic micro flapping-wing aircraft is a new technology brought about by the development of microelectronics and micromechanical technology. Through the research and development of micro bionic aircraft, we can improve scientific research and technological applications in this field, and remotely control bionic aircraft through radio signals to complete a series of various tasks.

[0003] Foreign countries have great expectations for the use of micro-aircraft in national defense and military. Swarm tactics and other technologies rely on the research and development of various micro-bionic aircraft. Bionic flapping-wing aircraft can be used as drone platforms and carry various platforms to complete reconnaissance, attack, communication, etc.

[0004] Existing flapping-wing aircraft have difficulty taking off because flapping wings have little lift and limited battery energy. Vertical take-off and landing hummingbird aircraft consume far more energy than level-flying fixed-wing aircraft. Minimizing the weight of the aircraft while ensuring structural strength has become a research focus. It is necessary to achieve a balance between materials and structures so that they are both light and able to withstand the flapping of the aircraft.

[0005] Micro flapping-wing aircraft operate in a low Reynolds number airflow environment, with low aerodynamic efficiency and small load. Research on improving the wing shape, flapping angle, flapping frequency and power consumption of flapping-wing aircraft to achieve higher efficiency by studying and learning the flapping wing systems of hummingbirds and insects has become a hot topic.

[0006] In the existing bionic hummingbird flapping wing layout, the motor is mostly arranged at the top, which will make the center of gravity distribution more unstable. The present invention arranges the drive motor at a position close to the center of gravity of the body, and a stable center of gravity is conducive to the stability of the posture.

[0007] On the other hand, the existing flapping wing generally uses a servo to control the wing surface or center of gravity to control the aircraft attitude. The existing micro-servo system is relatively heavy, which also makes it difficult for many researchers' bionic flapping wings to take off. The electromagnetic rudder weighs about 0.5g, but it needs to control the circuit module, which is also very heavy when added together, and new designs need to be researched and developed. The miniaturization and lightweighting of electronic devices are important for the progress of flapping wing research. The weight of domestic micro-servos is generally 1.5-2g. If three servos are used, the weight is at least 4.5g, which makes it very difficult for flapping wings to take off.

[0008] The transmission commonly used in flapping-wing aircraft are gears and transmission belts, and the torque is also very large when flapping wings are running at high speed. In a tiny space, the battery is generally 3.7V. Using two series-connected batteries with a voltage of 7.4V to drive some flapping-wing aircraft will increase the weight of the system. It is very important for this type of aircraft that the motor can be driven by a 3.7V low-voltage single battery.

[0009] The control board of the existing flapping-wing control system is mainly made of PCB materials. With the increase of electronic devices and functions, the area of ​​PCB boards will increase and the weight will also be heavier. It is important to study the application and design of new materials and lightweight circuit boards in the field of flight control. This type of bionic flapping-wing aircraft uses many types of hollow cup DC motors, but DC hollow cup motors have low power and short life and are relatively backward motors on flapping-wing aircraft. Summary of the invention

[0010] The present invention provides a bionic hummingbird flapping-wing aircraft with an ultralight structure and a control system. Through improvements in structure and materials, the overall mass of the aircraft is greatly reduced, and the stability is improved. The aircraft can achieve true flapping-wing flight without an external power cord and only relying on battery power.

[0011] A bionic hummingbird flapping-wing aircraft with an ultralight structure and a control system, comprising a frame and a wing system fixed on the frame, a power transmission system, a pitch servo control system, a roll servo control system and a micro-integrated flexible folding circuit board system;

[0012] The frame is composed of a carbon fiber cutting plate, including an upper frame and a lower frame, wherein the upper frame includes an upper bottom plate pulley frame, a bottom plate connecting member and a lower bottom plate pulley frame; the lower frame includes a suspension, a front support frame and a rear support frame fixed to the suspension, and a base fixed to the lower ends of the front support frame and the rear support frame; the suspension is fixed to the lower surface of the lower bottom plate pulley frame through a first hanging ear;

[0013] The wing system is composed of a pair of left and right wings, each wing includes a wing pulley rotatably fixed to the lower surface of the upper bottom plate pulley frame, a wing rod fixed on the wing pulley, a second hanging ear fixed to the lower surface of the lower bottom plate pulley frame, a wing rod rotating frame rotatably fixed to the second hanging ear, a wing root rod fixed to the wing rod rotating frame, and a wing membrane fixed to the wing rod and the wing root rod, wherein the wing membrane is provided with wing veins, and the wing membrane is provided with a wing membrane hole at the wing root near the frame;

[0014] The power transmission system realizes the flapping motion of a pair of wings by driving the wing pulley to rotate back and forth.

[0015] Furthermore, the power transmission system comprises a motor, a large gear, a large pulley, a connecting rod and a transmission belt;

[0016] The motor is fixed on the lower surface of the lower bottom plate pulley frame, the large gear is rotatably fixed on the upper surface of the lower bottom plate pulley frame, the motor gear at the output end of the motor passes through the lower bottom plate pulley frame and meshes with the large gear; a gear rocker arm is fixed on the large gear, the gear rocker arm is connected to the large pulley through a connecting rod, and the output of the motor is converted into reciprocating motion of the large pulley through the large gear and the connecting rod;

[0017] The transmission belt is composed of two circles of thin ropes. One end of the transmission belt is put on a wing pulley, and the other end passes through the large pulley, crosses each other, and is put on another wing pulley.

[0018] Furthermore, the pitch servo control system includes a pitch servo mounting frame fixed to the front side of the upper frame and a pitch servo fixed on the servo mounting frame; the pitch servo is provided with a first carbon fiber rudder arm, the first carbon fiber rudder arm is connected to one end of a metal wire, and the other end of the metal wire is connected to the upper end hole of the front support frame.

[0019] Preferably, the pitch servo and the rack mounting hole on the pitch servo mounting frame are fixed by screws, or the pitch servo and the pitch servo mounting frame are fixed by glue.

[0020] Furthermore, the roll servo control system includes a roll servo mounting frame fixed on the rear support frame and a roll servo fixed on the roll servo mounting frame; the roll servo is provided with a second carbon fiber rudder arm, the second carbon fiber rudder arm is connected to one end of a metal wire connecting rod, the other end of the metal wire connecting rod is connected to a third hanging ear, and the third hanging ear is fixed to the lower end surface of the suspension.

[0021] Furthermore, the flexible folding circuit board system uses a foldable flexible circuit board as a substrate, and the flexible circuit board is provided with a step-up and step-down power supply, an MCU single-chip computer, a barometric needle, an inertial navigation sensor, a magnetometer, a wireless communication module and an antenna;

[0022] The step-up and step-down power supply adopts the MP28163 chip solution, which is used to increase the battery voltage to 3.7V and then reduce it to other components; the MCU microcontroller outputs control PWM signals to the power transmission system, pitch servo control system and roll servo control system.

[0023] Preferably, the shape of the hole in the wing membrane is triangular, and the area of ​​the hole in the wing membrane accounts for 1 / 30 to 1 / 20 of the wing membrane. More preferably, the area of ​​the hole in the wing membrane accounts for 1 / 24 of the wing membrane.

[0024] The first hanging ear is fixed to the lower bottom plate pulley frame by a snap mechanism made of carbon fiber material in combination with glue; the suspension is fixed to the first hanging ear by rivets and gaskets.

[0025] The base is provided with a waist-shaped hole in the middle position for limiting the two wing root rods respectively.

[0026] The wing veins are composed of 0.3-0.5mm carbon fiber rods, which are fixed to the wing membrane by glue or tape; the wing rods are inserted into the hole structure of the wing pulley and fixed with glue, the upper end of the wing membrane is wrapped around the wing rod and fixed, and the wing root part of the wing membrane is sleeved on the wing root rod.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] 1. The present invention designs the power system motor at the center of gravity of the entire aircraft, thereby improving the stability of the aircraft.

[0029] 2. In the power transmission system of the present invention, a single large pulley is used to wind the conveyor belt, which cooperates with the motor and two wing pulleys to complete the flapping motion of a bunch of wings. The whole structure has high stability, which is conducive to the continuity of the flapping motion.

[0030] 3. The present invention designs a special ultra-light circuit board on the electronic circuit. The miniature integrated flexible folding circuit board can be folded, the inertial navigation part can be placed horizontally on the flapping-wing aircraft fuselage, and the main control part can be folded to achieve ultra-low weight and space area.

[0031] 4. The present invention adopts an ultra-light servo, each weighing only 0.5g. Combined with a carbon fiber rudder arm and a wire connecting rod, the ultra-light servo system greatly improves the flight time of the aircraft.

[0032] 5. The wing part of the present invention is based on the principle of bionics and the flight principle of hummingbirds and beetles. The linear speed of the wing root is very low. Holes are dug at the wing root of the artificial bionic flapping wing. This method can reduce flight resistance and is beneficial to the endurance and maneuverability of the flapping wing. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is an overall structural diagram of a bionic hummingbird flapping-wing aircraft with an ultra-light structure and a control system according to the present invention;

[0034] Figure 2 It is a structural diagram of the frame in the present invention;

[0035] Figure 3 is a structural diagram of the wing system of the present invention;

[0036] Figure 4 is a structural diagram of the power transmission system of the present invention;

[0037] Figure 5 It is a structural schematic diagram of a large pulley in a power transmission system;

[0038] Figure 6It is a schematic diagram of the cooperation between the transmission belt and the large pulley in the power transmission system;

[0039] Figure 7 It is a structural schematic diagram of the pitch servo control system in the present invention;

[0040] Figure 8 It is a structural schematic diagram of the rolling steering gear control system in the present invention;

[0041] Fig. 9 It is a schematic diagram of the structure of the flexible folding circuit board system in the present invention. DETAILED DESCRIPTION

[0042] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be pointed out that the embodiments described below are intended to facilitate the understanding of the present invention and do not have any limiting effect on the present invention.

[0043] like Figure 1 As shown, a bionic hummingbird flapping-wing aircraft with an ultralight structure and a control system includes a frame 1 and a wing system 2 fixed on the frame 1, a power transmission system 3, a pitch servo control system 4, a roll servo control system 5 and a miniature integrated flexible folding circuit board system 6.

[0044] like Figure 2 As shown, the frame 1 is composed of a 1mm thick carbon fiber cutting plate. In order to reduce its own weight, the components are hollowed out to reduce weight while ensuring the strength of the body as much as possible. Specifically, it includes an upper frame and a lower frame, wherein the upper frame includes an upper bottom plate pulley frame 101, two bottom plate connectors 102 and a lower bottom plate pulley frame 103. The lower frame includes a suspension 104, a front support frame 105 and a rear support frame 109 fixed to the suspension 104, and a base 106 fixed to the lower ends of the front support frame 105 and the rear support frame 109. The suspension 104 is fixed to the lower surface of the lower bottom plate pulley frame 103 through a first hanging ear 107. The base 106 is provided with two waist-shaped holes 108 in the middle position.

[0045] In this embodiment, the first hanging ear 107 and the lower bottom plate pulley frame 103 are fixed by a snap mechanism of carbon fiber material with glue; the suspension 104 and the first hanging ear 107 are fixed by rivets and gaskets. The suspension 104 and the front support frame 105 and the rear support frame 109 can be fixed by carbon fiber cutting plates or 3D printing materials.

[0046] like Figure 3As shown, the wing system is composed of a pair of left and right wings, each wing includes a wing pulley 201 rotatably fixed to the lower surface of the upper bottom plate pulley frame 101, a wing rod 202 fixed on the wing pulley 201, a second hanging ear 203 fixed to the lower surface of the lower bottom plate pulley frame 103, a wing rod rotating frame 204 rotatably fixed to the second hanging ear 203, a wing root rod 206 fixed to the wing rod rotating frame 204, and a wing membrane 208 fixed to the wing rod 202 and the wing root rod 206. A plurality of wing veins 207 are provided on the wing membrane 208, and a wing membrane hole 205 is provided at the wing root near the frame 1; in this embodiment, the shape of the wing membrane hole 205 is triangular, and the area of ​​the wing membrane hole 205 accounts for 1 / 24 of the wing membrane 208, and the wing membrane hole 205 can reduce air resistance.

[0047] The wing vein 207 is composed of a 0.3-0.5mm carbon fiber rod, which is fixed to the wing membrane 208 by glue or tape to strengthen the wing structure strength. The wing rod 202 is inserted into the hole structure of the wing pulley 201 and fixed with glue. The upper end of the wing membrane 208 is folded 1cm and wrapped around the wing rod 202 for fixation. The wing root part of the wing membrane 208 is sleeved on the wing root rod 206. The two waist-shaped holes 108 in the middle position of the base 106 are used to limit the two wing root rods 206 respectively.

[0048] The wing itself is not vertical, but is at an angle of 30 degrees to the vertical direction to obtain the best lift. The wing root rod 206 can rotate around the second hanging ear 203, which is manifested as the wing root rod 206 moving up and down, and the whole body rolling.

[0049] like Figure 4 As shown, the power transmission system 3 includes a motor 301, a large gear 303, a large pulley 306, a connecting rod 305 and a transmission belt 309. Specifically, the motor 301 uses a hollow cup DC motor or a brushless motor. The motor 301 is fixed to the lower surface of the lower bottom plate pulley frame 103, and the large gear 303 is rotatably fixed to the upper surface of the lower bottom plate pulley frame 103. The motor gear 304 at the output end of the motor 301 passes through the lower bottom plate pulley frame 103 and meshes with the large gear 303; a gear rocker arm 302 is fixed on the large gear 303, and the gear rocker arm 302 is connected to the large pulley 306 through a connecting rod 305. The output power of the motor 301 is converted into the reciprocating motion of the large pulley 306 through the gear and connecting rod system. A gasket 307 is provided on the upper end surface of the large pulley 306, which is rotatably fixed with the rotating shaft and the upper bottom plate pulley frame 101.

[0050] like Figure 5 As shown, a mounting hole 310 is provided on the lower end surface of the large pulley 306 , and the connecting rod 305 is rotatably connected to the large pulley through the mounting hole 310 .

[0051] like Figure 6As shown, one end of the transmission belt 309 is sleeved on a wing pulley 201 , and the other end crosses each other after passing through the large pulley 306 and is sleeved on another wing pulley 201 .

[0052] The large pulley 306 and the two wing pulleys 201 cooperate with the transmission belt 309 to form a rope transmission system. The reciprocating motion of the large pulley drives the two wing pulleys 201 to rotate forward and backward, and the transmission to the wings becomes a flapping motion. The flapping system composed of the large pulley 306 and the wing pulleys 201 requires a stable transmission belt 309. Double-sided tape is wrapped around the large pulley 306 and the two wing pulleys 201 to increase the friction of the transmission belt 309. The transmission belt 309 is composed of two circles of thin ropes. The ropes are wrapped around the pulleys for two circles and glue is added to enhance the firmness, forming a flexible and strong transmission system.

[0053] like Figure 7 As shown, the pitch servo control system 4 includes a pitch servo mounting frame 402 fixed to the front side of the upper frame and a pitch servo 406 fixed on the pitch servo mounting frame 402; the pitch servo 406 is provided with a first carbon fiber rudder arm 403, the first carbon fiber rudder arm 403 is connected to one end of a metal wire 404, and the other end of the metal wire 404 is connected to the upper end hole 405 of the front support frame 105.

[0054] When the pitch servo 406 moves, the upper frame rotates around the first hanging ear 107 to form pitch attitude control. The pitch servo 406 is fixed to the frame mounting hole 401 on the servo mounting frame 402 by screws, or, in order to reduce weight, the pitch servo 406 and the servo mounting frame can be fixed by glue.

[0055] like Figure 8 As shown, the roll servo control system 5 includes a roll servo mounting frame 503 fixed on the rear support frame 109 and a roll servo 505 fixed on the roll servo mounting frame 503; the roll servo 505 is provided with a second carbon fiber rudder arm 504, the second carbon fiber rudder arm 504 is connected to one end of the metal wire connecting rod 502, the other end of the metal wire connecting rod 502 is connected to the third hanging ear 501, and the third hanging ear 501 is fixed to the lower end surface of the suspension 104.

[0056] The roll servo 505 and the second carbon fiber rudder arm 504, the wire connecting rod 503, and the third hanging ear 501 constitute a roll control mechanism, which rotates around the third hanging ear 503 as a whole. The roll servo 505 is fixed on the roll servo mounting frame 503, and the installation method is the same as that of the pitch servo mounting frame 402.

[0057] In this embodiment, a (sub-micro 0.5g LZ) servo is used in a flapping-wing aircraft, and a single pitch servo 406 and a roll servo 505 weigh only 0.5g. The first carbon fiber rudder arm 403, the metal wire 404, the second carbon fiber rudder arm 504, and the metal wire connecting rod 503 all have a diameter of 0.5mm. The ultra-light servo control system greatly improves the flight time of the aircraft.

[0058] like Fig. 9 As shown, the flexible folding circuit board system 6 uses a foldable flexible circuit board 608 as a substrate, and the flexible circuit board 608 is provided with a step-up and step-down power supply 601, an MCU microcontroller 602, a pressure needle 603, an inertial navigation sensor 604, a magnetometer 605, a wireless communication module 606 and an antenna 607.

[0059] The step-up / step-down power supply 601 adopts the MP28163 chip solution, which is used to increase the battery voltage 3.7V (steady state) and reduce it to other components, so that the overall power supply stability is improved. The MCU microcontroller 602 outputs a control PWM signal to the power transmission system 3, the pitch servo control system 4 and the roll servo control system 5.

[0060] MCU 602 uses a single-chip microcomputer such as stm32f411ceu6; barometer 603 barometer spl006, as an aircraft altitude estimation sensor, is integrated with the data measured by the inertial navigation sensor 604 to generate aircraft data. The inertial navigation sensor 604 can be ICM-20608 or other models; wireless communication module 606 is responsible for communicating with the remote controller to receive instructions, the antenna 107 on the left is a ceramic antenna or a wire antenna, and the magnetometer 605 uses HMC5883L. The entire flexible folding circuit board system 6 weighs only 1.5g.

[0061] The embodiments described above provide a detailed description of the technical solutions and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, supplements and equivalent substitutions made within the scope of the principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A bionic hummingbird flapping-wing aircraft with an ultralight structure and a control system, characterized in that: It comprises a frame (1), a wing system (2) fixed on the frame (1), a power transmission system (3), a pitch steering gear control system (4), a roll steering gear control system (5), and a micro-integrated flexible folding circuit board system (6); The frame (1) is composed of a carbon fiber cutting plate, and includes an upper frame and a lower frame, wherein the upper frame includes an upper bottom plate pulley frame (101), a bottom plate connecting member (102) and a lower bottom plate pulley frame (103); the lower frame includes a suspension (104), a front support frame (105) and a rear support frame (109) fixed to the suspension (104), and a base (106) fixed to the lower ends of the front support frame (105) and the rear support frame (109); the suspension (104) is fixed to the lower surface of the lower bottom plate pulley frame (103) through a first hanging ear (107); The wing system is composed of a pair of left and right wings, each wing comprising a wing pulley (201) rotatably fixed to the lower surface of an upper bottom plate pulley frame (101), a wing rod (202) fixed on the wing pulley (201), a second hanging ear (203) fixed on the lower surface of a lower bottom plate pulley frame (103), a wing rod rotating frame (204) rotatably fixed to the second hanging ear (203), a wing root rod (206) fixed on the wing rod rotating frame (204), and a wing membrane (208) fixed to the wing rod (202) and the wing root rod (206), wherein the wing membrane (208) is provided with a wing vein (207), and the wing membrane (208) is provided with a wing membrane hole (205) at the wing root near the frame (1); the shape of the wing membrane hole (205) is triangular, and the area of ​​the wing membrane hole (205) accounts for 1 / 30 to 1 / 20 of the wing membrane (208); The power transmission system (3) realizes flapping motion of a pair of wings by driving the wing pulley (201) to rotate back and forth; The pitch servo control system (4) comprises a pitch servo mounting frame (402) fixed on the front side of the upper frame and a pitch servo (406) fixed on the servo mounting frame (402); the pitch servo (406) is provided with a first carbon fiber rudder arm (403), the first carbon fiber rudder arm (403) is connected to one end of a metal wire (404), and the other end of the metal wire (404) is connected to an upper end hole (405) of a front support frame (105); the pitch servo (406) is fixed to a frame mounting hole (407) on the pitch servo mounting frame (402) by screws, or the pitch servo (406) is fixed to the pitch servo mounting frame (402) by glue; The roll servo control system (5) comprises a roll servo mounting frame (503) fixed on the rear support frame (109) and a roll servo (505) fixed on the roll servo mounting frame (503); the roll servo (505) is provided with a second carbon fiber rudder arm (504), the second carbon fiber rudder arm (504) is connected to one end of a metal wire connecting rod (502), the other end of the metal wire connecting rod (502) is connected to a third hanging ear (501), and the third hanging ear (501) is fixed to the lower end surface of the suspension (104); The flexible folding circuit board system (6) uses a foldable flexible circuit board (608) as a substrate. The flexible circuit board (608) is provided with a step-up and step-down power supply (601), an MCU single chip (602), a pressure needle (603), an inertial navigation sensor (604), a magnetometer (605), a wireless communication module (606) and an antenna (607). The step-up and step-down power supply (601) adopts an MP28163 chip solution, which is used to increase the battery voltage 3.7V and then reduce it to other components. The MCU single chip (602) outputs a control PWM signal to a power transmission system (3), a pitch servo control system (4) and a roll servo control system (5).

2. The ultra-light structure and bionic hummingbird flapping-wing aircraft with a control system according to claim 1, characterized in that: The power transmission system (3) comprises a motor (301), a large gear (303), a large pulley (306), a connecting rod (305) and a transmission belt (309); The motor (301) is fixed on the lower surface of the lower bottom plate pulley frame (103), the large gear (303) is rotatably fixed on the upper surface of the lower bottom plate pulley frame (103), the motor gear (304) at the output end of the motor (301) passes through the lower bottom plate pulley frame (103) and meshes with the large gear (303); a gear rocker arm (302) is fixed on the large gear (303), the gear rocker arm (302) is connected to the large pulley (306) through a connecting rod (305), and the output of the motor (301) is converted into a reciprocating motion of the large pulley (306) through the large gear (303) and the connecting rod (305); The transmission belt (309) is composed of two circles of thin ropes. One end of the transmission belt (309) is sleeved on a wing pulley (201), and the other end crosses each other after passing through the large pulley (306) and is sleeved on another wing pulley (201).

3. The ultralight structure and bionic hummingbird flapping-wing aircraft with control system according to claim 1, characterized in that: The first hanging ear (107) and the lower bottom plate pulley frame (103) are fixed by a snap-fit ​​mechanism of carbon fiber material in combination with glue; the suspension (104) and the first hanging ear (107) are fixed by rivets and gaskets.

4. The ultralight structure and bionic hummingbird flapping-wing aircraft with control system according to claim 1, characterized in that: The base (106) is provided with a waist-shaped hole (108) at the middle position for respectively limiting the positions of the two wing root rods (206).

5. The ultra-light structure and bionic hummingbird flapping-wing aircraft with control system according to claim 1, characterized in that: The wing vein (207) is composed of a carbon fiber rod of 0.3-0.5 mm and is fixed to the wing membrane (208) by glue or tape; the wing rod (202) is inserted into the hole structure of the wing pulley (201) and fixed with glue, the upper end of the wing membrane (208) is wrapped around the wing rod (202) and fixed, and the wing root part of the wing membrane (208) is sleeved on the wing root rod (206).

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