Imma Perfetto
Cosmos science journalist
Researchers have created a soft robot that walks, hops, and swims using legs that resemble inflatable, wavey air dancers which grab customers’ attention on the roadside.
The machine is powered only by a continuous stream of air but moves surprisingly quickly and can even avoid obstacles. All this is accomplished without the aid of a computer, software, or sensors.
The continuous stream of air causes each of the soft, tubular legs to oscillate. On their own, each leg waves around randomly as kinks travel through it like an air dancer.
But when the legs are coupled together, something unexpected happens.
“Suddenly, order emerges from chaos,” says first author Alberto Comoretto, a PhD student in the Soft Robotic Matter Group at AMOLF in the Netherlands, an academic institute for fundamental physics with high societal relevance.
“There’s no code, no instructions. The legs simply fall into sync spontaneously, and the robot takes off.”
Credit: AMOLF/Alberto Comoretto
The machine can travel as quickly as 30 body lengths per second, which is orders of magnitude faster than other existing air-powered robots.
The synchronisation of its legs even allows it to adapt to obstacles in its path, reorienting around them. When moving from one environment to another, such as from land to water, its gait spontaneously shifts from an in-phase hopping pattern to a swimming freestyle.
“In biology, we often see similar decentralised intelligence,” says co-author Mannus Schomaker, also a PhD student in the Soft Robotic Matter Group.
“Sea stars, for example, coordinate hundreds of tube feet using local feedback and body dynamics, not a centralised brain.”
The research challenges the conventional idea that robots need complicated control systems to display lifelike behaviour.
“Simple objects, like tubes, can give rise to complex and functional behaviour, provided we understand how to harness the underlying physics,” says the study’s principal investigator, Associate Professor Bas Overvelde of AMOLF.
In fact, Overvelde prefers not to call the machine a robot at all.
“There is no brain, no computer. Essentially, it’s a machine. But when properly designed, it can outperform many robotic systems and behave like an artificial creature,” he says.
His team hopes to inspire new ways of thinking about robotic design, with simpler systems that are more adaptive and robust through physics, not computation and AI.
The machine is described in a new study published in the journal Science.
