A bioinspired revolving-wing drone with passive attitude stability and efficient hovering flight

TLDR

Small rotorcraft achieve agility with multiple compact rotors, yet this design incurs high energy demand and limited endurance, whereas large winged seeds use aerodynamic surfaces and delayed stalls to enable efficient unpowered autorotation. The study adopts samara‑inspired principles to markedly reduce power consumption in small aerial vehicles. The robot features two rotors and oversized revolving wings that exploit unsteady aerodynamics, and its design incorporates passive attitude stability to eliminate the need for rapid feedback. The 35.1‑gram dual‑wing drone achieved powered‑gyration hovering, halved power consumption versus benchmark multirotors, delivered 14.9‑minute flight (up to 24.5 min with a larger battery), and enabled position‑controlled mapping and surveillance with a 21.5‑gram payload.

Abstract

Among small rotorcraft, the use of multiple compact rotors in a mechanically simple design leads to impressive agility and maneuverability but inevitably results in high energetic demand and acutely restricted endurance. Small spinning propellers used in these vehicles contrast with large lifting surfaces of winged seeds, which spontaneously gyrate into stable autorotation upon falling. The pronounced aerodynamic surfaces and delayed stalls are believed key to efficient unpowered flight. Here, the bioinspired principles are adopted to notably reduce the power consumption of small aerial vehicles by means of a samara-inspired robot. We report a dual-wing 35.1-gram aircraft capable of hovering flight via powered gyration. Equipped with two rotors, the underactuated robot with oversized revolving wings, designed to leverage unsteady aerodynamics, was optimized for boosted flight efficiency. Through the analysis of flight dynamics and stability, the vehicle was designed for passive attitude stability, eliminating the need for fast feedback to stay upright. To this end, the drone demonstrates flight with a twofold decrease in power consumption when compared with benchmark multirotor robots. Exhibiting the power loading of 8.0 grams per watt, the vehicle recorded a flight time of 14.9 minutes and up to 24.5 minutes when equipped with a larger battery. Taking advantage of the fast revolving motion to overcome the severe underactuation, we also realized position-controlled flight and illustrated examples of mapping and surveillance applications with a 21.5-gram payload.