An adjustable body based ornithopter
By using an adjustable fuselage design and flexible materials, the flapping-wing aircraft utilizes a rotary motor to adjust the wing angle and simplifies the transmission structure, thus solving the problem of insufficient overall performance of existing flapping-wing aircraft and achieving efficient and stable flight control and miniaturization.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- HARBIN INSTITUTE OF TECHNOLOGY (SHENZHEN) (INSTITUTE OF SCIENCE AND TECHNOLOGY INNOVATION HARBIN INSTITUTE OF TECHNOLOGY SHENZHEN)
- Filing Date
- 2024-02-01
- Publication Date
- 2026-08-04
AI Technical Summary
Existing flapping-wing aircraft have shortcomings in overall performance, maneuverability, flight efficiency, stable hovering and fixed-point takeoff and landing capabilities. Furthermore, their complex transmission structure leads to excessive mass, making miniaturization difficult. They also have poor adaptability to rigid materials and unsatisfactory transmission control modes, which affect flight stability.
It adopts an adjustable fuselage design, using a rotary motor to adjust the angle between the forewing and the fuselage. Combined with flexible materials and a simplified transmission structure, it provides lift and thrust through the flapping of the forewing and rearwing, and controls the flight direction through the rotary motor. The fuselage frame made of flexible materials is used to adapt to different flight environments.
It achieves flexible control and efficient flight of flapping-wing aircraft, reduces overall weight, improves aerodynamic performance and flight stability, meets biomimetic design goals, and adapts to complex flight environments.
Smart Images
Figure CN117842353B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of flapping-wing aircraft technology, and particularly relates to a flapping-wing aircraft based on an adjustable fuselage. Background Technology
[0002] Ornithopter flight combines the advantages of fixed-wing and rotary-wing flight, integrating lift, hovering, and propulsion functions. It has high maneuverability and flexibility and is considered the most effective flight mode for small size and low Reynolds number.
[0003] Miniature flapping-wing aircraft do not use propellers, resulting in low noise and high stealth capabilities. Combined with their naturally camouflaged shape, this makes them valuable for modern military, police tracking, and reconnaissance applications. In the field of aircraft design, biomimicry is a crucial technique. Among numerous flying creatures, the dragonfly, with its four wings that can flap independently, can perform a series of complex flight maneuvers, including gliding, hovering, diving, sharp turns, evasive maneuvers, inverted flight, side-flying, and vertical ascents and descents, making it a perfect model for flapping-wing aircraft. The dragonfly's superior flight performance is attributed to its unique physiological structure and the highly efficient aerodynamics of its wing flapping.
[0004] Currently, the flapping-wing prototype still has room for improvement in terms of overall performance, maneuverability, and flight efficiency, and does not yet possess good capabilities for programmed flight, stable hovering, and fixed-point takeoff and landing. Most dragonfly-inspired flapping-wing aircraft use mechanical transmission to drive wing movement, employing complex transmission structures to control each of the four wings, resulting in a relatively large prototype mass, which severely impacts the aerodynamic performance. Furthermore, the complexity of the transmission structure and the high precision requirements for manufacturing and assembly make miniaturization difficult. Reducing the weight of the flapping-wing prototype and decreasing the weight of the transmission structure and the number of motors significantly limits its maneuverability.
[0005] Flight control of a dragonfly-inspired flapping-wing aircraft is a challenging problem because simulating the agile flight of a dragonfly in nature involves complex dynamics and control issues. For most flapping-wing prototypes, adjusting flight direction by controlling the tail fin with servos to change airflow has several drawbacks, such as the large mass of the servos and the difficulty in meeting lightweight requirements. In the context of dragonfly-inspired flapping-wing prototypes, dragonfly flight is independent of the tail, relying instead on the coordinated flapping of two pairs of wings for agile flight. Therefore, using the tail fin to control direction is not the most ideal control mode and requires further optimization. Currently, many existing prototypes can control each of the two pairs of wings (four wings) individually. While this control mode can meet the requirement for agile wing control, it also has several disadvantages. First, achieving such complex control requires a particularly large number of transmission structures, which naturally increases the overall weight of the aircraft, hindering flight and potentially causing lift to fall below gravity, preventing takeoff. Second, independent control of the four wings makes it difficult to ensure perfectly symmetrical flapping of the left and right wings, resulting in poor flight stability. Therefore, in order to better simulate the flight of dragonflies, some new design and control strategies may need to be considered.
[0006] For the design of the overall fuselage frame, most existing technologies currently use rigid materials such as resin, carbon fiber, or nylon. These materials have low density, which can reduce the overall weight of the prototype and improve flight performance to some extent. However, rigid materials have poor adaptability during flight and are difficult to cope with complex flight environments. Secondly, from a biomimetic perspective, the bodies of flapping-wing insects in nature exhibit mostly flexible material properties. Therefore, the use of rigid materials does not align with the goals of biomimetic design, and the aerodynamic performance of rigid materials is also lower than that of flexible materials. Summary of the Invention
[0007] The purpose of this invention is to provide a flapping-wing aircraft based on an adjustable fuselage, which can rotate the entire forewing structure at a small angle by a rotary motor, thereby changing the angle between the forewing and the overall flapping-wing prototype to form a certain angle, thus achieving the purpose of controlling the forward direction of the flapping-wing aircraft.
[0008] The present invention is implemented as follows: a flapping-wing aircraft based on an adjustable fuselage includes a fuselage frame, a forewing drive module, a rearwing drive module, a battery module, a flight control module, a forewing, a rearwing, and a steering module; the forewing drive module and the rearwing drive module are respectively fixed to the front end and the rear end of the fuselage frame, the forewing is driven by the forewing drive module, and the rearwing is driven by the rearwing drive module;
[0009] Both the battery module and the flight control module are fixed to the fuselage frame. The battery module is used to provide power to the forewing drive module, the rearwing drive module and the flight control module. The flight control module is used to control the forewing drive module, the rearwing drive module and the steering module, thereby controlling the flapping motion and steering of the flapping wing aircraft.
[0010] The steering module includes a rotary motor, which is fixed to the fuselage frame. The rotating shaft of the rotary motor is fixedly connected to the forewing drive module. When the rotary motor is working, it can adjust the deflection angle between the forewing drive module and the fuselage frame, thereby controlling the forward direction of the flapping-wing aircraft.
[0011] Furthermore, the flapping-wing aircraft also includes a front connector and a connecting rod, the rotary motor is fixed to the front connector, and the rear end of the front connector is hinged to the fuselage frame through the connecting rod.
[0012] Furthermore, a first limiting structure is provided at each end of the connecting rod, and a second limiting structure is provided on the fuselage frame at a position corresponding to the first limiting structure. When the connecting rod rotates to a certain set angle, the first limiting structure and the second limiting structure interfere with each other in space, thereby limiting the angle of attack of the forewing within a certain range and realizing adaptive angle of attack change.
[0013] Furthermore, each end of the connecting rod is provided with a cam handle. By rotating the two cam handles, the front connector can be clamped and fixed to the fuselage frame. By adjusting the different angles at which the front connector is tilted relative to the fuselage frame, the angle of attack of the forewing can be changed.
[0014] Furthermore, the rotary motor is a rotary motor with a large reduction ratio.
[0015] Furthermore, the fuselage frame is made of flexible material.
[0016] Furthermore, the design of the fuselage frame mimics the body shape and mass distribution of a dragonfly, with the center of gravity located at the front end of the fuselage frame.
[0017] Furthermore, the forewing drive module includes a forewing drive motor, a forewing linkage structure, and a forewing planetary gear; the forewing drive motor drives the forewing planetary gear to rotate through the forewing linkage structure, thereby enabling the forewing to flap up and down, providing lift and thrust for the entire machine.
[0018] Furthermore, the rear wing transmission module includes a rear wing drive motor, a rear wing linkage structure, and a rear wing planetary gear; the rear wing drive motor drives the rear wing planetary gear to rotate through the rear wing linkage structure, thereby enabling the rear wing to flap up and down, providing lift and thrust for the entire aircraft.
[0019] Furthermore, the forewing drive module and the rearwing drive module are detachably installed at the front and rear positions of the fuselage frame, respectively. The lift and thrust of the entire aircraft can be adjusted by adjusting the distance between the forewing drive module and the rearwing drive module.
[0020] Compared with the prior art, the beneficial effects of this invention are as follows:
[0021] The flapping-wing aircraft of this invention can rotate the entire forewing structure at a small angle using a rotary motor, changing the angle between the forewing and the overall flapping-wing aircraft to form a certain angle, thereby achieving the purpose of controlling the forward direction of the flapping-wing aircraft. This structure uses only one additional rotary motor to achieve the function of controlling the steering of the flapping-wing aircraft, avoiding complex gear mechanisms or the use of servo-tail fins. Attached Figure Description
[0022] Figure 1 This is a three-dimensional structural diagram of a flapping-wing aircraft provided in Embodiment 1 of the present invention;
[0023] Figure 2 yes Figure 1 An enlarged view of the front end of the flapping-wing aircraft shown;
[0024] Figure 3 yes Figure 1 An enlarged view of the rear end of the flapping-wing aircraft shown;
[0025] Figure 4 yes Figure 1 An enlarged view of the variable angle of attack structure of the flapping-wing aircraft shown;
[0026] Figure 5 This is a three-dimensional structural schematic diagram of a flapping-wing aircraft provided in Embodiment 2 of the present invention;
[0027] Figure 6 yes Figure 5 An enlarged view of the variable angle of attack structure of the flapping-wing aircraft shown. Detailed Implementation
[0028] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.
[0029] Example 1:
[0030] Please refer to Figure 1 This embodiment illustrates a flapping-wing aircraft based on an adjustable fuselage, including a fuselage frame 1, a forewing drive module 2, a rearwing drive module 3, a battery module 4, a flight control module, a forewing 5, a rearwing 6, and a steering module. The forewing drive module 2 and the rearwing drive module 3 are fixed to the front and rear ends of the fuselage frame 1, respectively. The forewing 5 is drive-connected to the forewing drive module 2, and the rearwing 6 is drive-connected to the rearwing drive module 3.
[0031] Both the battery module 4 and the flight control module are fixed on the fuselage frame 1. The battery module 4 provides power to the forewing drive module 2, the rear wing drive module 3 and the flight control module. The flight control module controls the forewing drive module 2, the rear wing drive module 3 and the steering module, thereby controlling the flapping motion and steering of the flapping wing aircraft.
[0032] Specifically, please refer to Figure 2 The forewing drive module 2 includes a forewing drive motor 21, a forewing linkage structure 22, and a forewing planetary gear 23. The forewing drive motor 21 drives the forewing planetary gear 23 to rotate through the forewing linkage structure 22, thereby enabling the forewing 5 to flap up and down, providing lift and thrust for the whole machine.
[0033] Please refer to Figure 3 The rear wing drive module 3 includes a rear wing drive motor 31, a rear wing connecting rod structure 32, and a rear wing planetary gear 33. The rear wing drive motor 31 drives the rear wing planetary gear 33 to rotate through the rear wing connecting rod structure 32, thereby enabling the rear wing 6 to flap up and down, providing lift and thrust for the whole machine.
[0034] The forewing drive module 2 and the rearwing drive module 3 are detachably installed at the front and rear ends of the fuselage frame 1, respectively. The lift and thrust of the entire aircraft can be adjusted by adjusting the distance between the forewing drive module 2 and the rearwing drive module 3.
[0035] The steering module includes a rotary motor 7 with a large reduction ratio. The rotary motor 7 is fixed on the fuselage frame 1. The rotating shaft of the rotary motor 7 is fixedly connected to the forewing drive module 2. When the rotary motor 7 is working, it can adjust the deflection angle between the forewing drive module 2 and the fuselage frame 1, thereby controlling the forward direction of the flapping wing aircraft.
[0036] In this embodiment, the control scheme for the two transmission modules is as follows: the forewing drive motor 21 and the rear wing drive motor 31 have only one rotation direction, and the speed is controlled by the voltage magnitude controlled by the flight control module; the control scheme for the rotary motor 7 is as follows: the flight control module can provide a voltage signal from -5V to 5V to the rotary motor 7. When the voltage is negative, the rotary motor 7 drives the forewing structure 2 to rotate counterclockwise, changing the running direction, and vice versa.
[0037] The flapping-wing aircraft in this embodiment also includes a front connector 8 and a connecting rod 9. A rotary motor 7 is fixed to the front connector 8, and the rear end of the front connector 8 is hinged to the fuselage frame 1 via the connecting rod 9. By using the front connector 8, the forewing drive module 2 fixed to the front connector 8, and the rotary motor 7 fixed to the fuselage frame 1, the angle between the front connector 8 and the fuselage frame 1 can be changed to alter the angle of attack of the flapping-wing aircraft when facing different flight requirements. At a larger angle of attack, the flapping-wing aircraft can meet the requirements for hovering or climbing; at a smaller angle of attack, the flapping-wing aircraft can obtain higher thrust and achieve high-speed forward flight.
[0038] The design of the flapping-wing aircraft is inspired by deformable and adaptable organisms in nature, such as birds and insects. Flexible materials can be used to create an aircraft that achieves flight through a flexible, deformable fuselage structure. The flexible fuselage aircraft utilizes flexible materials and structures, allowing the entire fuselage to deform and adjust its shape to adapt to different flight conditions. In this embodiment, the overall fuselage frame 1 is made of lightweight flexible material (currently TPU), manufactured using 3D printing technology. In practical applications, the entire flapping-wing aircraft, except for necessary standard components such as motors, uses flexible materials for all other structures. This fuselage frame 1 has excellent deformability and low manufacturing cost, better aligning with the goals of biomimetic design, and exhibits better flight performance compared to traditional rigid plastic frames. With the flexible fuselage frame 1, during flight, the flexible fuselage frame 1 interacts with the air and deforms. Under the effect of fluid-structure interaction, this significantly improves the aerodynamic efficiency of the flapping-wing aircraft, greatly enhancing its aerodynamic performance.
[0039] The variable angle of attack structure used in this embodiment is as follows:
[0040] Please refer to Figure 4A first limiting structure 91 is provided at both ends of the connecting rod 9, and a second limiting structure 11 is provided on the fuselage frame 1 at a position corresponding to the first limiting structure 91. When the connecting rod 9 rotates to a certain set angle, the first limiting structure 91 and the second limiting structure 11 interfere with each other spatially, thereby limiting the angle of attack of the canard wing 5 within a certain range and realizing adaptive angle of attack variation. This embodiment achieves the purpose of adapting to various flight environments by changing the size of the angle of attack through a simple mechanical structure.
[0041] During flight, by remote control, the voltage output to the motor of the forewing drive module 2 is increased, which increases the flapping frequency of the forewing 5 and generates more lift. This causes the forewing 5 to rotate through the first limiting structure 91, increasing the angle of attack and generating even more lift. Conversely, by reducing the voltage to the forewing drive motor 21, the flapping frequency of the forewing 5 is reduced. Under the influence of gravity, the forewing 5 structure naturally rotates downward, reducing the angle of attack. At this smaller angle of attack, the greater thrust is obtained, making it more suitable for forward flight.
[0042] The overall fuselage frame 1 is designed to mimic the body shape and mass distribution of a dragonfly, with the majority of the mass concentrated at the front end and lighter at the tail, thus placing the center of gravity in the front half of the fuselage frame 1. Based on lift mechanisms, a specific angle of attack is assigned to the forewings 5 to enhance the overall lift of the flapping-wing aircraft. Structural optimization of the fuselage frame 1 retains only the main support structures for the motor drive and the connections between different structures, significantly reducing the mass of the flapping-wing aircraft. Simultaneously, the battery module 4 and flight control module are selected with appropriate sizes to further reduce the overall mass of the flapping-wing aircraft, achieving miniaturization and lightweight design.
[0043] Example 2:
[0044] Please refer to Figure 5 This embodiment provides another flapping-wing aircraft based on an adjustable fuselage. The difference between this embodiment and the first embodiment is that this embodiment adopts a different variable angle of attack structure. The variable angle of attack structure of this embodiment is as follows:
[0045] Please refer to Figure 6 Cam handles 92 are provided at both ends of the connecting rod 9. By rotating the two cam handles 92, the front connecting piece 8 can be clamped and fixed to the fuselage frame 1. By adjusting the different angles of the front connecting piece 8 relative to the fuselage frame 1, the angle of attack of the forewing 5 can be changed. Through the above scheme, the angle of attack can be changed manually.
[0046] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. A flapping-wing aircraft based on an adjustable fuselage, characterized in that, It includes a fuselage frame, a forewing drive module, a rearwing drive module, a battery module, a flight control module, a forewing, a rearwing, and a steering module; the forewing drive module and the rearwing drive module are respectively fixed to the front and rear ends of the fuselage frame, the forewing is driven by the forewing drive module, and the rearwing is driven by the rearwing drive module. Both the battery module and the flight control module are fixed to the fuselage frame. The battery module is used to provide power to the forewing drive module, the rearwing drive module and the flight control module. The flight control module is used to control the forewing drive module, the rearwing drive module and the steering module, thereby controlling the flapping motion and steering of the flapping wing aircraft. The steering module includes a rotary motor, which is fixed to the fuselage frame. The rotating shaft of the rotary motor is fixedly connected to the forewing drive module. When the rotary motor is working, it can adjust the deflection angle between the forewing drive module and the fuselage frame, thereby controlling the forward direction of the flapping-wing aircraft. It also includes a front connector and a connecting rod. The rotary motor is fixed to the front connector, and the rear end of the front connector is hinged to the fuselage frame through the connecting rod. The two ends of the connecting rod are respectively provided with a first limiting structure, and the fuselage frame is provided with a second limiting structure at the position corresponding to the first limiting structure. When the connecting rod rotates to a certain set angle, the first limiting structure and the second limiting structure interfere with each other in space, thereby limiting the angle of attack of the forewing within a certain range and realizing adaptive angle of attack change.
2. The flapping-wing aircraft as described in claim 1, characterized in that, The connecting rod is provided with cam handles at both ends. By rotating the two cam handles, the front connector can be clamped and fixed to the fuselage frame. By adjusting the different angles at which the front connector is tilted relative to the fuselage frame, the angle of attack of the forewing can be changed.
3. The flapping-wing aircraft as described in claim 1 or 2, characterized in that, The rotary motor is a rotary motor with a large reduction ratio.
4. The flapping-wing aircraft as described in claim 1 or 2, characterized in that, The fuselage frame is made of flexible material.
5. The flapping-wing aircraft as described in claim 1 or 2, characterized in that, The design of the fuselage frame mimics the body shape and mass distribution of a dragonfly, with the center of gravity located at the front end of the fuselage frame.
6. The flapping-wing aircraft as described in claim 1 or 2, characterized in that, The forewing drive module includes a forewing drive motor, a forewing linkage structure, and a forewing planetary gear. The forewing drive motor drives the forewing planetary gear to rotate through the forewing linkage structure, thereby enabling the forewing to flap up and down, providing lift and thrust for the entire aircraft.
7. The flapping-wing aircraft as described in claim 1 or 2, characterized in that, The rear wing drive module includes a rear wing drive motor, a rear wing linkage structure, and a rear wing planetary gear. The rear wing drive motor drives the rear wing planetary gear to rotate through the rear wing linkage structure, thereby enabling the rear wing to flap up and down, providing lift and thrust for the entire aircraft.
8. The flapping-wing aircraft as described in claim 1 or 2, characterized in that, The forewing drive module and the rearwing drive module are detachably installed at the front and rear positions of the fuselage frame, respectively. The lift and thrust of the entire aircraft can be adjusted by adjusting the distance between the forewing drive module and the rearwing drive module.