A teeny robot designed to replicate the wing dynamics of rhinoceros beetles could be well-suited for search-and-rescue missions, as well as spying on real insects, according to researchers at Switzerland’s Institute of Technology Lausanne and South Korea’s Konkuk University.
Roughly twice the size of a beetle and weighing slightly more than a CD (18 grams), the microrobot’s rapid, insectlike movements draw from research into how beetles deploy their wings. Unlike birds and bats, which rely on “well-developed pectoral and wing muscles” to outstretch their wings, the researchers observed that “rhinoceros beetles can effortlessly deploy their hindwings without necessitating muscular activity,” they wrote in a paper published in Nature this week. To test their observations, they made the robot, which they named KUBeetle.
There was already plenty of footage of insect-inspired robots online — some extremely tiny, some like a swarm of ants, and others reminiscent of cicadas. However, the researchers say their robotic critter is unique in how it folds up its wings at rest and then passively deploys them to take flight and remain in the air. The researchers filmed the robot while airborne and slowed the footage (to 20% of the actual speed) to show off its elegant, rhythmic flaps.
Lead researcher and postdoctoral scientist Hoang-Vu Phan told Gizmodo that the project was inspired in part by the rhinoceros beetle’s fandom in Korea.
“Rhinoceros beetles are one of the largest flying insects and are very popular in Korea,” he said. Beyond flying, the insects are able to “perform many other modes of locomotion such as crawling, perching on various surfaces, and even burrowing their way underground,” he added. “They can fold and tuck their hindwings under the forewings called elytra in an origami-like fashion and quickly deploy them to power flight. These capabilities have therefore inspired us to study their locomotive biomechanics and build robotic replicas for more than ten years.”
!["Rhinoceros Beetle Ready For A Flight" © Hoang Vu Phan](https://gizmodo.com/app/uploads/2024/08/Rhinoceros-beetle-ready-for-a-flight_Credit_Hoang-Vu-Phan.jpg)
As for practical applications, Phan told Tech Xplore that the robot’s foldable wings enable it to “be used for search and rescue missions in confined spaces. The robot can also perch and crawl, and its folding function makes its wings less susceptible to damage during crawling.
!["The Flapping Microrobot Takes Flight With Passive Deploying Retracting Wings" © Hoang Vu Phan](https://gizmodo.com/app/uploads/2024/08/The-flapping-microrobot-takes-flight-with-passive-deploying-retracting-wings_Credit_Hoang-Vu-Phan.jpg)
Phan, who has studied the beetles for more than ten years, also said the robot could be disguised to help biologists spy on real insects in forests — a use “for which conventional rotary-wing drones are not applicable,” he said. The robot might even make a decent engineering toy for kids, Phan suggested, explaining that the robot’s “low-flapping frequency is very safe and human-friendly.” That’s not unlike actual rhinoceros beetles, which neither bite nor sting, despite their somewhat intimidating appearance.