Bionic butterfly and flight control system thereof

Abstract

According to the bionic butterfly and the flight control system thereof disclosed by the invention, intelligent flight of the bionic butterfly is realized in a breakthrough manner by fusing a high-precision radio navigation module and a multi-stage environment perception control system; based on polar coordinate positioning of VOR / DME signals and a course deviation dynamic correction algorithm, the navigation precision is improved to a navigation level standard; an original five-mode switching architecture (including a sudden strong wind emergency mechanism) realizes millisecond-level mode arbitration and wing-tail cooperative control through three-dimensional perception of real-time wind speed, wind direction and duration. The deep combination of bionic and engineering mechanics not only reproduces the wave type energy-saving flight path of the butterfly in the nature, but also greatly improves the wind resistance and reduces the energy consumption through the innovative designs of free falling obstacle avoidance, asymmetric flapping and the like.

Description

Technical Field

[0001] This invention belongs to the field of biomimetic aircraft technology, and particularly relates to a biomimetic butterfly and its flight control system. Background Technology

[0002] Bionic butterflies are a typical example of miniature bionic aircraft. Their core design concept is to achieve lightweight and highly maneuverable flight capabilities by mimicking the aerodynamic characteristics and movement patterns of butterflies in nature. These devices have unique applications in fields such as environmental monitoring, military reconnaissance, and disaster relief.

[0003] The core challenge currently facing biomimetic butterfly technology lies in the disconnect between mechanical structure and control logic. Traditional solutions often employ open-loop control strategies, capable of only simple reproduction of preset trajectories. Their limitations are primarily threefold: First, the navigation system relies on a combination of inertial measurement unit (IMU) and photoelectric encoder. In GPS-denied environments, positioning errors accumulate and amplify, leading to an inability to autonomously recover when heading deviations exceed 15°. Second, the environmental response mechanism is rigid. While existing biomimetic aircraft (such as CN109131800A) can identify wind speed changes, they lack tiered processing capabilities, resulting in wingbeat frequency adjustment delays of up to 500ms when encountering sudden gusts. Third, energy consumption optimization is achieved solely by reducing wing area, sacrificing aerodynamic efficiency. This phenomenal biomimetic approach struggles to meet the demands for long endurance and high robustness in scenarios such as field monitoring and disaster relief. Summary of the Invention

[0004] To address the problems in the prior art, the present invention proposes the following technical solution: The flight control system of the biomimetic butterfly includes: Radio navigation module: The radio navigation module combines position sensor signals with VOR / DME signals to provide precise navigation and heading correction for the biomimetic butterfly using polar coordinate positioning principle; the radio navigation module includes a heading deviation detection model and a multi-level correction control algorithm; The heading deviation detection model includes a phase difference calculation model and a heading deviation angle ( In the phase difference calculation model, the VOR system calculates the phase difference by comparing the reference phase signal with the variable phase signal. Calculate the azimuth angle ( ): Where the phase difference ( The solution is obtained through a phase-shifting algorithm in an airborne receiver, and the calculation formula is as follows: in The time difference between the zero-crossing points of the two signals. The signal period; Heading deviation angle calculation: Let the predetermined track angle be and the actual heading measured by the sensor be , then: in The formula for calculating magnetic declination compensation is as follows: in , These are the northward and eastward components of the geomagnetic field, respectively. It is the magnetic tilt angle. Geographic latitude; The multi-level correction control algorithm includes: long-range correction (>10 nautical miles), using a double correction coefficient, and the control law is: Where the proportionality coefficient Integral time Differential time ; Mid-range correction (3-10 nautical miles), standard PID control: In the transfer function For the Laplace operator, the parameters are adjusted as follows: , , ; Near-range correction (<3 nautical miles), half-angle correction combined with feedforward compensation: Where the feedforward coefficient ; The control module adjusts the flight mode of the bionic butterfly in real time based on the external environment. The flight modes include basic mode, headwind mode, crosswind mode, tailwind mode, and sudden strong wind mode.

[0005] As a preferred embodiment of the above technical solution, the control module includes a mode switching core logic framework and a multi-mode switching unit; The core logic framework for mode switching includes an input data source and a switching priority. The input data source includes: Wind sensor: Real-time wind speed V (m / s) and duration t w (Second); Altitude sensor: Current altitude h (m) and rate of change of altitude ; Wind duration threshold T th (seconds); Strong wind speed threshold V s (m / s); Basic mode wind speed threshold Vw (m / s); The switching priority of each mode is as follows: sudden strong wind mode (highest priority) > headwind / crosswind mode > tailwind mode > basic mode.

[0006] As a preferred embodiment of the above technical solution, in the sudden strong wind response mode, the biomimetic butterfly quickly folds its wings into a streamlined shape, avoids the core area of ​​the airflow through free fall, and then unfolds its wings again. The triggering condition is: V≥V s ; The control formula is: ;in The duration (in seconds) for the wings to fold. For dynamic compensation; The sudden strong wind response mode also includes free fall height compensation: .

[0007] As a preferred embodiment of the above technical solution, in the headwind mode, lift is maintained by increasing the wingbeat frequency, while the torque is balanced by the tail swinging at the rear of the body, causing the body to tilt at a 45° angle to counteract the wind force. The triggering condition is as follows: V s ≥V≥V w And wind direction angle ∈[135°, 225°] and t w ≥T th Adjusting the wingbeat frequency: ,in, This is the reference frequency.

[0008] As a preferred embodiment of the above technical solution, in the crosswind mode, the center of gravity position is changed by the swinging of the tail located at the rear of the body, and stable flight is achieved in conjunction with the flapping of asymmetrical wings (amplitude difference). The triggering condition is as follows: V s ≥V≥V w And wind direction angle ∈[45°, 135°] and t w ≥T th Asymmetric wing control: ,in The amplitude difference is dynamically adjusted between the left and right wings, with a maximum difference of 30%. Tail swing angle .

[0009] As a preferred embodiment of the above technical solution, in the tailwind mode, the wingbeat frequency is actively reduced and gliding flight is initiated, thereby reducing energy consumption. The triggering condition is: V s ≥V≥V w And wind direction angle ∈[-45°, 45°] and t w ≥T th Adjusting the wingbeat frequency: ,in, This is the reference frequency.

[0010] As a preferred embodiment of the above technical solution, in the basic mode, the biomimetic butterfly flies within a set height using a combination of horizontal and vertical motion. Horizontal flight is characterized by straight-line motion, while vertical flight is characterized by periodic up-and-down undulations due to rapid wing vibrations, resulting in a wave-like overall trajectory. This effectively utilizes airflow and reduces energy consumption. The triggering condition is: V < V s or t w <T th The wave trajectory equation is: , Where A is the fluctuation amplitude, and the vertical fluctuation is 90° out of phase with the horizontal motion to take advantage of the airflow.

[0011] As a preferred embodiment of the above technical solution, the control module further includes a mode switching arbitration mechanism, the conflict resolution formula of which is: in, Score based on priority. , , These are the weighting coefficients, and their weighting configuration is as follows: Sudden strong winds: , , ; Other modes: , , ; The system calculates the score every 100ms, and the highest score mode is activated; the mode switching delay is forcibly locked at 200ms to prevent oscillation.

[0012] A biomimetic butterfly, wherein the biomimetic butterfly is used in the flight control system of the aforementioned biomimetic butterfly, the biomimetic butterfly comprising: The torso, which has a built-in power supply unit, drive unit, and control unit; The antennae are attached to the head end of the trunk. The head of the antennae is spherical and contains a built-in sensor assembly, which includes a wind sensor, an altitude sensor, and a position sensor. The tail is attached to the tail end of the body. The tail swings and rotates 360° around the connection between the tail and the body, thereby changing the overall center of gravity of the biomimetic butterfly. The wings are mounted on both sides of the body and connected to the drive unit, and the two wings are independently controlled by the drive unit.

[0013] The beneficial effects of this invention are as follows: This invention achieves groundbreaking intelligent flight mimicking a biomimetic butterfly by integrating a high-precision radio navigation module with a multi-level environmental perception and control system. Polar coordinate positioning and dynamic heading deviation correction algorithms based on VOR / DME signals elevate navigation accuracy to nautical standards. The unique five-mode switching architecture (including a sudden strong wind emergency mechanism) achieves millisecond-level mode arbitration and wing-tail coordinated control through real-time three-dimensional perception of wind speed, direction, and duration. This deep integration of biomimicry and engineering mechanics not only replicates the wave-like energy-saving flight trajectory of butterflies in nature but also significantly improves wind resistance and reduces energy consumption through innovative designs such as free-fall obstacle avoidance and asymmetrical wing flapping. Its modular design can also be extended to other micro-bionic aircraft, driving the entire field towards environmentally adaptive flight. Detailed Implementation

[0014] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments.

[0015] Example The biomimetic butterfly and flight control system of this invention consists of a radio navigation module and a multi-mode control module. The biomimetic butterfly's body has a built-in power supply unit (3.7V lithium battery), a drive unit (micro servo motor group), and a control unit (STM32H743 main control chip). The antennae integrate wind speed / altitude / position sensors. The tail uses a carbon fiber flexible joint to achieve 360° swinging and is used for center of gravity adjustment. The swing angle encoder (AS5048A) has a feedback resolution of 12bit, and the dynamic counterweight movement range is ±10mm (stepper motor 0.05mm / step). The wings are composed of an independently driven shape memory alloy skeleton and a polyimide film. The shape memory alloy wire (0.2mm in diameter) is pre-stretched by 5% and then embedded in the wing veins. When heated to 70°C, it generates a contraction displacement. The dual-sided independent control circuit has a maximum output current of 500mA, a PWM modulation frequency of 1kHz, and supports dynamic adjustment of amplitude difference of 30%.

[0016] The flight control system of the biomimetic butterfly includes: Radio navigation module: The radio navigation module combines position sensor signals with VOR / DME signals to provide precise navigation and heading correction for the biomimetic butterfly using polar coordinate positioning principle; the radio navigation module includes a heading deviation detection model and a multi-level correction control algorithm; The heading deviation detection model includes a phase difference calculation model and a heading deviation angle ( In the phase difference calculation model, the VOR system calculates the phase difference by comparing the reference phase signal with the variable phase signal. Calculate the azimuth angle ( ): Where the phase difference ( The solution is obtained through a phase-shifting algorithm in an airborne receiver, and the calculation formula is as follows: in The time difference between the zero-crossing points of the two signals. The signal period; Heading deviation angle calculation: Let the predetermined track angle be and the actual heading measured by the sensor be , then: in The formula for calculating magnetic declination compensation is as follows: in , These are the northward and eastward components of the geomagnetic field, respectively. It is the magnetic tilt angle. Geographic latitude; The multi-level correction control algorithm includes: long-range correction (>10 nautical miles), using a double correction coefficient, and the control law is: Where the proportionality coefficient Integral time Differential time ; Mid-range correction (3-10 nautical miles), standard PID control: In the transfer function For the Laplace operator, the parameters are adjusted as follows: , , ; Near-range correction (<3 nautical miles), half-angle correction combined with feedforward compensation: Where the feedforward coefficient ; The flight control system of the bionic butterfly also includes a control module, which adjusts the flight mode of the bionic butterfly in real time based on the external environment. The flight modes include basic mode, headwind mode, crosswind mode, tailwind mode, and sudden strong wind mode. The control module includes a core logic framework for mode switching and a multi-mode switching unit; The core logic framework for mode switching includes an input data source and a switching priority. The input data source includes: Wind sensor: real-time wind speed V (m / s) and duration tw (seconds); Altitude sensor: Current altitude h (m) and rate of change of altitude ; Wind duration threshold 5 (seconds); Strong wind speed threshold 5 (m / s); Basic mode wind speed threshold 2 (m / s); The switching priority of each mode is as follows: sudden strong wind mode (highest priority) > headwind / crosswind mode > tailwind mode > basic mode.

[0017] In the sudden strong wind response mode, the bionic butterfly quickly folds its wings into a streamlined shape, avoids the core area of ​​the airflow through free fall, and then unfolds its wings again. The triggering condition is: V≥5. The control formula is: ;in The duration (in seconds) for the wings to fold. For dynamic compensation; The sudden strong wind response mode also includes free fall height compensation: .

[0018] In headwind mode, lift is maintained by increasing wingbeat frequency, while the torque is balanced by the tail movement located at the rear of the body, causing the body to tilt at a 45° angle to counteract the wind force. The triggering condition is: 5≥V≥2 and wind direction angle ∈[135°, 225°] and t w ≥5, Wing vibration frequency adjustment: ,in, This is the reference frequency.

[0019] In crosswind mode, the center of gravity is changed by the movement of the tail at the rear of the body, combined with the flapping of asymmetrical wings (amplitude difference) to achieve stable flight. The triggering condition is: 5≥V≥2 and wind direction angle ∈[45°, 135°] and t w ≥5, Asymmetric wing control: ,in The amplitude difference is dynamically adjusted between the left and right wings, with a maximum difference of 30%. Tail swing angle .

[0020] In tailwind mode, the wingbeat frequency is actively reduced and gliding flight is initiated to reduce energy consumption. The triggering conditions are: 2 ≥ V ≥ 5 and wind angle. ∈[-45°, 45°] and t w ≥5, Wing vibration frequency adjustment: ,in, This is the reference frequency.

[0021] In its basic mode, the biomimetic butterfly flies within a set altitude using a combination of horizontal and vertical motion. Horizontal flight is represented by straight-line motion, while vertical flight is characterized by periodic up-and-down undulations due to rapid wing vibrations, resulting in a wave-like overall trajectory. This effectively utilizes airflow and reduces energy consumption. The triggering condition is: V < 2 or t w <5; The wave trajectory equation is: , Where A is the fluctuation amplitude, and the vertical fluctuation is 90° out of phase with the horizontal motion to take advantage of the airflow.

[0022] The control module also includes a mode switching arbitration mechanism, whose conflict resolution formula is as follows: in, Score based on priority. , , These are the weighting coefficients, and their weighting configuration is as follows: Sudden strong winds: , , ; Other modes: , , ; The system calculates the scores of all feasible modes in parallel and selects the mode with the highest score as a candidate; if the mode with the highest score is different from the current mode, a switching logic is triggered (subject to a time threshold t). w ≥T th ).

[0023] Change execution and control safeguards: a. Forced Priority Override: In the sudden strong wind mode, when V≥5, the current mode is directly interrupted, and the wing-folding action is executed first; Headwind / Crosswind mode: The wind force must be sustained for a certain duration (i.e., t) w ≥T th It can only be activated if there is a short-term gust of wind.

[0024] b. Anti-oscillation design: The system calculates the score every 100ms and activates the highest score mode; after the new mode is activated, it is prohibited to switch again within 200ms to prevent frequent jumps caused by sensor noise.

[0025] Example Scenario 1: Sudden strong wind (V=5m / s, t) w=0.2 seconds): When the wind speed reaches 5 m / s and the duration is only 0.2 seconds, the impact force of the airflow on the bionic butterfly is far greater than the response speed of its aerodynamic control system, causing the fuselage to plummet violently in a short period. According to the principles of fluid dynamics, such sudden strong winds significantly reduce the lift coefficient, causing the rate of change of altitude to increase instantaneously. During the wing-folding motion (0.3 seconds), the bionic butterfly exhibits near-free fall motion. The theoretical change in altitude within 0.2 seconds is: That is, the rate of change of height The score is 2; at this time, the score for the sudden strong wind is calculated as follows: S=0.6*5+0.1+0.04+0.3*2=4.2 (highest priority score), and the switching action is: immediately fold the wings and ignore the scores of other modes.

[0026] Example Scenario 2: Continuous headwind (V=3m / s, t) w =6 seconds): Under sustained headwind conditions, the biomimetic butterfly maintains lift balance by adjusting its wing angle of attack and flapping frequency, resulting in a typically small rate of altitude change. The average vertical velocity under a 3 m / s headwind is 0.4 m / s - 0.6 m / s; here, we take the midpoint of 0.5 m / s. The headwind mode score is calculated as: S = 0.4 * 3 + 0.4 * 1.2 + 0.2 * 0.5 = 1.78 (highest priority score), and satisfies V... s ≥V≥V w t w ≥T th Mode switching is now in effect.

[0027] It should be noted that the switching interval between headwind and crosswind modes should be ≥1 second to protect the drive unit and prevent overload; when the battery level is below 20%, the time threshold T is automatically shortened. th After 3 seconds, low-power modes such as tailwind gliding will be triggered first.

[0028] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it.

Claims

1. A flight control system for a biomimetic butterfly, characterized in that, Comprise: Radio navigation module: the radio navigation module combines with VOR / DME signal through position sensor, provides accurate navigation and heading correction for bionic butterfly through polar coordinate positioning principle; the radio navigation module comprises heading deviation detection model and multi-stage correction control algorithm; The course deviation detection model includes a phase difference resolving model and a course deviation angle ) calculation, in the phase difference resolving model, the VOR system calculates the phase difference ) calculation ) calculation: Where the phase difference ( The solution is obtained through a phase-shifting algorithm in an airborne receiver, and the calculation formula is as follows: wherein is the time difference between the zero crossings of the two signals, is the period of the signal; Heading deviation angle calculation: let the predetermined track angle be, the sensor measured heading be, then: wherein is the magnetic deviation angle compensation amount, and the calculation formula is: wherein , are the north and east components of the geomagnetic field, respectively, is the magnetic inclination, is the geographic latitude; The multi-stage correction control algorithm comprises: long distance correction (> 10 nautical miles), adopts double correction coefficient, and the control law is: wherein the proportionality factor , integration time , differentiation time ; Medium distance correction (3-10 nautical miles), standard PID control: where the transfer function is is the Laplacian operator, and the parameters are adjusted to , , ; Short distance correction (< 3 nautical miles), half angle correction combined with feedforward compensation: where the feedforward coefficient ; Control module, the control module controls the flight mode of bionic butterfly based on real-time regulation of external environment, and the flight mode comprises basic mode, headwind mode, crosswind mode, tailwind mode and sudden strong wind mode.

2. The flight control system of the bionic butterfly according to claim 1, characterized in that, The control module comprises mode switching core logic framework and multi-mode switching unit; The mode switching core logic framework comprises input data source and switching priority, and the input data source comprises: Wind sensor: real-time wind speed V (m / s) and duration t w (seconds); Height sensor: current height h (m) and rate of change of height ; wind duration threshold T th (seconds); strong wind speed threshold V s (m / s); basic mode wind speed threshold V w (m / s); The switching priority of each mode is: sudden strong wind mode (highest priority) > headwind / crosswind mode > tailwind mode > basic mode.

3. The flight control system of the bionic butterfly according to claim 2, characterized in that, The burst strong wind coping mode, the bionic butterfly quickly gathers wings to be streamlined, avoids the airflow core area through free fall after re-expanding wings, and the triggering condition is: V≥V s ; The control formula is: ; wherein is the wing retraction duration (seconds), is the dynamic compensation; The burst strong wind coping mode further includes free fall height compensation: .

4. The flight control system of the bionic butterfly according to claim 3, characterized in that, In the headwind mode, the wing beat frequency is increased to maintain the lift, and the tail swing set at the tail of the body is used to balance the moment, so that the body is inclined at an angle of 45° to offset the wind force, and the triggering condition is: V s ≥V≥V w and the wind direction angle ∈ [135°, 225°] and t w ≥T th , wing beat frequency adjustment: wherein is the reference frequency.

5. The flight control system of the bionic butterfly according to claim 4, characterized in that, In the crosswind mode, the tail swing set at the tail of the body is used to change the center of gravity, and the asymmetric wing beat (amplitude difference) is used to realize stable flight, and the triggering condition is: V s ≥V≥V w and wind direction angle ∈ [45°, 135°] and t w ≥T th , asymmetric wing control: wherein is the amplitude difference, left / right wing amplitude difference dynamic adjustment, maximum difference 30%; Tail swing angle .

6. The flight control system of the bionic butterfly according to claim 5, characterized in that, In the downwind mode, the wing-flapping frequency is actively reduced and gliding flight is performed, thereby reducing energy consumption, and the triggering condition is: V s ≥ V ≥ V w and the wind direction angle ∈ [-45°, 45°] and t w ≥ T th , the wing-flapping frequency adjustment: wherein, is the reference frequency.

7. The flight control system of the bionic butterfly according to claim 6, characterized in that, In the basic mode, the bionic butterfly flies in a combination of horizontal and vertical movements within a set height. The horizontal flight is represented by straight-line movement, while the vertical direction is represented by periodic up-and-down fluctuations due to rapid wing vibration. The overall trajectory presents a wave-like pattern, effectively utilizing air flow and reducing energy consumption. The triggering condition is: V < V s or t w <T th ; the wave trajectory equation is: , ; where A is the fluctuation amplitude, and the phase difference between vertical fluctuation and horizontal movement is 90° to utilize air flow.

8. The flight control system of the bionic butterfly according to claim 7, characterized in that, The control module further comprises a mode switching arbitration mechanism, and the conflict resolution formula is: wherein, is a priority score, , , is a weight coefficient, whose weight configuration is: Sudden strong wind: , , ; Other modes: , , ; The system calculates the score every 100 ms, and the mode with the highest score is activated; the mode switching delay is forced to lock for 200 ms to prevent oscillation.

9. A biomimetic butterfly, characterized in that, The bionic butterfly is applied to the flight control system of the bionic butterfly in any one of claims 1-8, and the bionic butterfly comprises: Trunk, the trunk is built-in power supply unit, driving unit and control unit; Antenna, the antenna is installed at the head end of the trunk, the head of the antenna is spherical, and a sensor assembly is built-in in the antenna, the sensor assembly comprises a wind sensor, a height sensor and a position sensor; Tail, the tail is installed at the tail of the trunk, the tail swings around the connection part of the tail and the body by 360°, so as to change the overall center of gravity of the bionic butterfly; Wing, the wing is installed on both sides of the trunk and connected with the driving unit, and the two wings are controlled independently by the driving unit.

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