Beetle-Inspired Flight

Birds, bats, and bees each have unique ways of deploying and retracting their wings using distinct muscles. However, when it comes to smaller insects, such as beetles, the mechanism becomes more complex. Scientists have long debated whether these tiny creatures use muscles to power their wings. Beetles, in particular, exhibit a fascinating flying mechanism that involves a pair of stiff forewings, known as elytra, and a pair of foldable, membranous hindwings.

At rest, the hindwings of beetles are neatly folded under the protective case of the elytra. But before take-off, the elytra open fully, releasing the hindwings in an origami-like fashion. Recent research on beetles' hindwings has left scientists puzzled about how these delicate structures are powered. However, a breakthrough study led by Dario Floreano at EPFL has shed light on this mystery.

Through a combination of high-speed cameras and tests on robotic models, the research team discovered that beetles' hindwings are passively deployed and retracted. The hindwings leverage the elytra to facilitate their movement, while the flapping motion forces the wings to unfold. This innovative finding has significant implications for the design of microrobots that could potentially navigate confined spaces with ease.

EPFL researchers have already applied this newfound knowledge to develop a flapping microrobot that mimics the passive mechanism observed in beetles. By harnessing control synergies and physical interactions, the microrobot is capable of taking off, flying, and landing efficiently. The study, which has been published in the prestigious journal Nature, highlights the importance of leveraging natural evolution to enhance the design of robotic systems.

Dario Floreano, the director of the Laboratory of Intelligent Systems at EPFL, emphasizes the significance of this research by stating, “Contrary to the assumption that each motion requires a dedicated mechanism, this study shows that natural evolution leverages control synergies and physical interactions to reduce complexity, save energy, and gain resilience.” The team's findings challenge previous assumptions about the role of muscles in the wing deployment process of beetles' hindwings.