Flapping mechanism with independently controllable start and end positions

Abstract

The application provides a flapping mechanism with independently controllable flapping start position, comprising a wing rod, a connecting rod A, a connecting rod linear servo, a motor gear, a connecting rod B, a transmission wheel A, a transmission wheel B, a swing rod connecting piece, a rocker connecting piece, a micro linear servo, a speed reduction motor, a fuselage support and a swing rod linear servo. The application generates active yawing torque by flapping difference of two sides of the wing surface, fundamentally solves the problem that the vertical tail fails in the case of low flow velocity, and also solves the problems of poor disturbance resistance and poor maneuverability of the flapping wing aircraft in the low speed case. In addition, in the gliding stage, the upwash angle of the two sides of the wing surface and the tail can be controlled respectively, so that more bionic, flexible and efficient gliding flight is realized. The sub-aircraft has the characteristics of flight attitude bionics, strong visual confusion, low flight noise and high efficiency, and can be used in outdoor close-range reconnaissance, high-altitude long-endurance surveillance reconnaissance, wild animal close-range video shooting and other task scenes, and has important significance and value in the future.

Description

Technical Field

[0001] This invention relates to the field of aviation technology, specifically to a flapping wing mechanism in which the start and end positions of flapping can be independently controlled. Background Technology

[0002] In recent years, with the continuous development of science and technology, the high efficiency, realistic flight attitude, and strong visual deception of ornithopter aircraft have received increasing attention. Ornithopter aircraft play an irreplaceable role in missions requiring high levels of low-impact capability. Currently, the drive mechanisms of ornithopter aircraft can be broadly divided into two types: one is a linkage mechanism driven by an electric motor, and the other is direct drive by a servo motor.

[0003] The linkage mechanism approach is characterized by using a geared motor to drive a multi-link mechanism to achieve flapping motion of the wing surfaces. Its advantages include mature design theory, high power density, and simple control. However, the control input is limited to adjusting the motor speed to control the flapping frequency. This approach requires the addition of horizontal and vertical tail fins for pitch and yaw control, while roll control relies on the wing's inherent stability. Examples include Northwestern Polytechnical University's "Dove" and Nanjing University of Aeronautics and Astronautics' large twin-segment flapping wing. The simultaneous flapping motion of both wing surfaces means that yaw torque cannot be actively generated, necessitating the addition of a vertical tail fin or additional power unit for yaw control. Adding a vertical tail fin has the following disadvantages: firstly, it loses the most significant characteristic of a flapping wing aircraft—its biomimetic flight shape; secondly, as an airflow control surface, the vertical tail fin's airspeed is insufficient at high angles of attack and low speeds, resulting in inadequate control torque.

[0004] In summary, existing linkage-driven flapping-wing aircraft have the following main drawbacks:

[0005] 1. It can only change the flapping motion of both sides simultaneously, and cannot independently control the flapping motion of one side.

[0006] 2. There is a coupling problem between flapping amplitude and dihedral angle, that is, changing the flapping amplitude will change the dihedral angle.

[0007] 3. Due to the extensive use of gears, the mechanical structure is complex and has low reliability.

[0008] The characteristic of the servo-driven direct-drive system is that the wing flapping is achieved by controlling the reciprocating rotation of the servo motor. The flexibility of servo control allows for independent control of the start and end positions of flapping on a single wing surface, enabling differential control of both wings and thus controlling the aircraft's pitch, heading, and roll. Examples include Festo's "eMotionButterfly" and the butterfly-inspired aircraft from Beijing University of Aeronautics and Astronautics. The disadvantages of the servo-driven direct-drive system are its low power density. For the same weight, servo-driven aircraft have a low flapping frequency, resulting in relatively low lift, lower maximum takeoff weight, smaller payload, and limitations in functionality and flight time. Summary of the Invention

[0009] To address the problems of existing technologies, this invention provides a flapping wing mechanism with independently controllable flapping start and end positions. The flapping mechanism is more flexible, and the differential control of flapping on both sides can generate effective yaw torque, pitch torque, and roll torque. It can also effectively control the attitude of the aircraft at low speeds and high angles of attack, thus ensuring flight stability.

[0010] This invention provides a flapping wing mechanism with independently controllable flapping start and end positions, including a fuselage support and a wing rod connected to the fuselage support via a rotating joint. A reduction motor is fixed on the fuselage support, and the reduction motor drives a transmission gear set to rotate via a motor gear. A sway bar linear servo is fixed on the wing rod. A groove is formed in the middle of the wing rod, and a sway bar connector is disposed in the groove. One end of the sway bar connector is connected to a linkage assembly, and the other end is connected to the servo arm of the sway bar linear servo. The linkage assembly includes a connecting rod that is engaged with the sway bar. Link A and link B are connected. Link B is connected to the transmission gear set and has a groove. A linear servo is fixed on link A. One end of link A is connected to a rocker arm connector, and the other end is locked in the groove of link B by a slider. A linear servo that drives the slider to slide along the groove is fixed on link B. A miniature linear servo is fixed on the transmission gear set. A rocker arm connector is installed in the transmission gear set. One end of the rocker arm connector is connected to link B, and the other end is connected to the servo arm of the miniature linear servo.

[0011] In a further improvement, the linear servo is bonded to the connecting rod B with adhesive, and the miniature linear servo is bonded to the transmission wheel assembly with adhesive.

[0012] In a further improvement, the transmission gear set includes transmission wheel A and transmission wheel B, with the motor gear on the reduction motor meshing with transmission wheel B, and transmission wheel B meshing with transmission wheel A.

[0013] In a further improvement, the motor gear is connected to the geared motor shaft using an interference fit.

[0014] In a further improvement, the slider hole of the connecting rod linear servo is connected to the screw hole at the bottom of the connecting rod A via a screw.

[0015] The working principle of this invention is as follows: Based on the calculation formula of the ratio of the limit position to the reciprocating time of the four-bar linkage, the flapping parameters of the four-bar linkage can be changed by adjusting one or more of the following: adjusting the position of link A relative to the arm rod by the pendulum linear servo; adjusting the relative position of link A and link B by the link linear servo; and adjusting the relative position of the end of link B on the drive wheel by the micro servo. Within a certain range, the change of the start and end position of flapping on one side can be achieved. At the same time, the meshing of the transmission wheel and the transmission wheel 7 ensures the consistency of the flapping frequency on both sides, which is beneficial to the stability of flight.

[0016] The beneficial effects of this invention are as follows:

[0017] 1. The flapping mechanism is more flexible. By changing the characteristic parameters of the three links, the upper flapping limit position, the lower flapping limit position, and the ratio of the time occupied by the upper and lower flapping can be effectively changed.

[0018] 2. The differential control of flapping on both sides can generate effective yaw moment, pitch moment and roll moment, which fundamentally solves the problem of failure of horizontal and vertical tails when the incoming flow speed is low. It also solves the problem of poor anti-disturbance ability and poor maneuverability of flapping-wing aircraft at low speed.

[0019] 3. The active control torque generated by changing the flapping parameters of the two wing surfaces is unaffected by factors such as incoming flow and can effectively control the attitude of the aircraft even at low speeds and high angles of attack.

[0020] 4. Under different incoming flow conditions, the flapping parameters can be changed to switch the aircraft mode, such as entering the maximum speed mode, maximum lift mode, or highest efficiency mode.

[0021] 5. The meshing of the drive wheels on both sides ensures that the flapping frequency on both sides is the same, which can improve flight stability.

[0022] 6. This design eliminates the need for a vertical tail fin, making it more similar in appearance to birds in nature. It is more biomimetic, visually deceptive, and features low flight noise and high efficiency. It can be used in missions such as outdoor close-range reconnaissance, high-altitude long-endurance surveillance and reconnaissance, and close-range wildlife photography, and has important significance and value in the future. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a front view of the flapping wing mechanism of the present invention;

[0025] Figure 2 This is a schematic diagram of the present invention.

[0026] In the appendix Figure 1 Types: 1. Wing rod; 2. Link A; 3. Link linear servo; 4. Motor gear; 5. Link B; 6. Drive wheel A; 7. Drive wheel B; 8. Rocker arm connector; 9. Rocker arm connector; 10. Miniature linear servo; 11. Gear motor; 12. Fuselage support; 13. Rocker arm linear servo. Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] One specific embodiment of the present invention is as follows: Figure 1 and Figure 2 As shown, it has the following connection structure: including wing rod 1, connecting rod A2, connecting rod linear servo 3, motor gear 4, connecting rod B5, transmission wheel A6, transmission wheel B7, rocker arm connector 8, rocker arm connector 9, miniature linear servo 10, geared motor 11, fuselage support 12 and rocker arm linear servo 13.

[0029] The wing rod 1 is connected to the fuselage support 12 via a smooth rod screw;

[0030] Linkage A2 is connected to the swing arm connector 8 via a smooth rod screw;

[0031] Link A2 is engaged in the groove of link B5;

[0032] The swing arm connector 8 passes through the groove in the wing shaft 1, and its front end is connected to the connecting rod A2 by a screw, and its rear end is connected to the servo arm of the swing arm linear servo 13 by a screw.

[0033] The swashplate linear servo 13 is glued to the wing rod 1;

[0034] The linear servo 3 is glued to the connecting rod B5.

[0035] The slider hole of the linear servo 3 is connected to the screw hole at the bottom of the connecting rod A2 via a screw;

[0036] Motor gear 4 is connected to the shaft of geared motor 11 by an interference fit;

[0037] Drive wheel A6 is connected to the body bracket 12 via a smooth rod screw;

[0038] The rocker arm connector 9 is connected to the connecting rod B5 at the front end via a screw through the groove of the transmission wheel B7, and to the servo arm of the micro linear servo motor 10 at the rear end via a screw.

[0039] The miniature linear servo motor 10 is connected to the drive wheel B7 by glue;

[0040] Drive wheel B7 is connected to the body support 12 via a smooth rod screw;

[0041] The geared motor 11 is connected to the machine body bracket 12 by screws;

[0042] Motor gear 4 meshes with transmission wheel B;

[0043] Drive wheel B7 meshes with drive wheel A6.

[0044] This invention also provides a method for independent control of the flapping start and end positions. Based on the calculation formula of the ratio of the limit position to the reciprocating time of the four-bar linkage, the flapping parameters of the four-bar linkage can be changed by adjusting one or more of the following: adjusting the position of link A2 relative to arm link 1 by the swing arm linear servo 13; adjusting the relative position of link A2 and link B5 by the link linear servo 3; and adjusting the relative position of the end of link B5 on the drive wheel 7 by the micro servo 10. Within a certain range, the change of the flapping start and end positions on one side can be realized. At the same time, the meshing of the transmission wheel 6 and the transmission wheel 7 ensures the consistency of the flapping frequency on both sides, which is beneficial to the stability of flight.

[0045] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on its differences from other embodiments. In particular, for the device embodiments, the above descriptions are merely preferred embodiments of the present invention. Since they are fundamentally similar to the method embodiments, the descriptions are relatively simple, and relevant parts can be referred to the descriptions of the method embodiments. The above descriptions are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention, without departing from the principle of the present invention, should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A flapping wing mechanism with independently controllable flapping start and end positions, characterized in that: The system includes a fuselage support frame and a wing rod connected to the fuselage support frame via a rotating joint. A geared motor is fixed to the fuselage support frame, and the geared motor drives a transmission gear set to rotate via a motor gear. A swivel linear servo is fixed to the wing rod. A groove is formed in the middle of the wing rod, and a swivel connector is disposed within the groove. One end of the swivel connector is connected to a connecting rod assembly, and the other end is connected to the servo arm of the swivel linear servo. The connecting rod assembly includes a connecting rod A and a connecting rod B that are connected in a mating manner. Connecting rod B is connected to the transmission gear set, and a groove is formed on connecting rod B. A connecting rod linear servo is fixed to connecting rod A. A linear servo has a connecting rod A, one end of which is connected to a rocker arm connector, and the other end of which is engaged in a groove in a connecting rod B via a slider. A linear servo that drives the slider to slide along the groove is fixed on the connecting rod B. A miniature linear servo is fixed on the transmission gear set, which has a groove. A rocker arm connector is installed in the groove, one end of which is connected to the connecting rod B, and the other end is connected to the servo arm of the miniature linear servo. The transmission gear set includes a transmission wheel A and a transmission wheel B. The motor gear on the reduction motor meshes with the transmission wheel B, and the transmission wheel B meshes with the transmission wheel A.

2. The flapping wing mechanism with independently controllable flapping start and end positions according to claim 1, characterized in that: The linear servo is bonded to the connecting rod B with adhesive, and the miniature linear servo is bonded to the transmission wheel assembly with adhesive.

3. The flapping wing mechanism with independently controllable flapping start and end positions according to claim 1, characterized in that: The motor gear is connected to the geared motor shaft by an interference fit.

4. The flapping wing mechanism with independently controllable flapping start and end positions according to claim 1, characterized in that: The slider hole of the connecting rod linear servo is connected to the screw hole at the bottom of the connecting rod A by a screw.

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