In context
In early 2025, flapping-wing aircraft research was advancing toward greater agility and efficiency, yet most designs relied on fixed crank-rocker mechanisms that limited wing motion to a single amplitude. Birds, however, adjust wing amplitude to optimize flight under varying airflow, a capability that remained difficult to replicate without sacrificing performance.
What was reported
A team from the University of Science and Technology Beijing proposed a variable-amplitude flight strategy based on motor closed-loop control. They modeled the motor dynamics and wing motion to build a closed-loop model of the wing flapping angle, then designed a controller for precise angle control. The strategy includes a gliding function and was validated through numerical simulations.
For practical application, they upgraded a falcon-inspired flapping-wing platform with sensors and a Falcon 2.0 flight control board, adding less than 30 g. Ground tests showed the wings could reach a specified glide angle within 0.2 s and perform variable-amplitude flapping at 1–4 Hz. Turntable experiments demonstrated a 14.7% increase in lift compared with traditional cyclic flapping, indicating improved airflow utilization.
Flight tests confirmed stable gliding within 0.5 s and variable-amplitude flight at 2–3 Hz, validating the strategy's effectiveness.
Why it mattered
This work enhances the degrees of freedom in wing flapping, offering a practical solution for medium-to-large flapping-wing robots to improve flight efficiency and adaptability—key for applications in surveillance, environmental monitoring, and other industrial uses where efficient aerial platforms are needed.
“The proposed variable-amplitude flight strategy enhances the degrees of freedom of the wing flapping motion of flapping-wing aircraft, providing an effective solution for performance optimization and practical applications.”
Source: 《机器人》期刊 (robot.sia.cn) · Published 2025-01-15 · “扑翼飞行器的变幅飞行策略的设计与实现”