At a Glance
- Inspired by the autorotation of samara seeds, researchers built a 32-gram monocopter with a single actuator capable of achieving a 26-minute position-controlled hovering flight.
- The minimalist design prioritizes aerodynamic efficiency over brute-force thrust, featuring a single airfoil and motor that eliminate complex gearboxes and flapping parts for superior mechanical and structural simplicity.
- Scientists used a data-driven surrogate optimization method to fine-tune the drone’s wing shape, pitching angle, and mass distribution for minimal power consumption during stable hovering flight.
- The prototype demonstrates superior power efficiency, achieving a high power loading of 9.1 grams per watt, which significantly outperforms other micro air vehicles of a comparable size and weight.
- This breakthrough in efficient, small-scale flight opens doors for applications like reusable weather sensors and has set a new goal for a 60-minute flight by Singapore’s 60th anniversary.
Researchers at the Singapore University of Technology and Design have developed a groundbreaking drone that mimics the spinning descent of a maple seed, enabling exceptionally long flight times. The 32-gram monocopter—a drone with a single wing—can hover under complete automatic control for 26 minutes, a significant leap in endurance for aircraft of its size. Led by Associate Professor Foong Shaohui, the team drew inspiration from the samara, or maple seed, which uses a natural aerodynamic principle called autorotation to create lift efficiently. This nature-inspired approach challenges the conventional multi-rotor drone design, which often struggles with poor energy efficiency at a small scale.
Unlike quadcopters that rely on the brute-force thrust of multiple fast-spinning propellers, the monocopter uses a single motor to spin its entire winged body. This rotation generates lift across its large, single airfoil in a stable, energy-efficient manner. The design is mechanically simple, eliminating the need for complex and energy-draining components like gearboxes or flapping linkages. This minimalist strategy directly addresses a core challenge in micro-robotics: as drones get smaller, their power consumption typically becomes disproportionately high. By adopting nature’s solution, the SUTD team has created a machine where, as Foong explained in a university press release, “every part of a maple seed contributes to lift.”
To perfect the design, the researchers employed a sophisticated AI-powered technique known as surrogate optimization. This data-driven method enabled them to virtually test and refine numerous configurations of wing shape, pitch angle, and mass distribution to find the optimal balance for minimal power consumption. The resulting prototype is remarkably efficient, boasting a power loading of 9.1 grams per watt—a key metric indicating the amount of weight that can be lifted per unit of power. The team’s full methodology and results were published in the IEEE Robotics and Automation Letters journal.
The monocopter’s impressive endurance and simple construction open doors for a variety of low-cost, long-duration missions. One promising application is a reusable, lightweight radiosonde for weather sensing, a project that won the Sustainability award at The James Dyson Award 2024. The research team is now focused on developing custom components to enhance payload capacity further and extend flight time, with the ambitious goal of creating a version that can fly for over 60 minutes. This work demonstrates how combining human-centered observation with AI-driven engineering can push the boundaries of what small aerial robots can achieve.
References
- Cai, X., Zhong, S., Tan, T. M., Ang, W. J., & Foong, S. (2025). Design and optimization of a samara-inspired lightweight monocopter for extended endurance. IEEE Robotics and Automation Letters, 10(7), 7214–7221. https://doi.org/10.1109/LRA.2025.3575316
- Singapore University of Technology & Design. (2025, August 8). Small but mighty: A seed-inspired monocopter idea takes flight. Tech Xplore; Singapore University of Technology & Design. https://techxplore.com/news/2025-08-small-mighty-seed-monocopter-idea.html
