According to a study published in Science, an AMOLF research team developed a soft robot that walks, hops, and swims without a brain, electronics, or artificial intelligence. It is just soft tubes, air, plus some ingenious physics. Possible future applications include smart medicines and space technology.
From left to right: Alberto Comoretto, Manus Schomaker, Bas Overvelde. Image Credit: AMOLF
The study revealed one of the simplest and fastest soft robots to date. It lacks sensors, software, and a computer. Nevertheless,using its body and the way it interacts with the environment, it moves with unexpected autonomy and coordination.
How Does it Work?
Underneath the movement is an overlooked principle. Consider those unstable, inflated tube dancers flailing around in front of petrol stations. The same physics that causes them to wriggle may hold the secret to the next generation of autonomous robots.
Chaos Turns into Order
Powered solely by a continuous stream of air, each of the robot's soft, tubular legs begins to oscillate, much like those tube dancers. On its own, each leg moves randomly. However, when many are combined, something unexpected occurs: their motions quickly synchronize, resulting in rhythmic locomotion patterns.
Suddenly, order emerges from chaos. There is no code, no instructions. The legs simply fall into sync spontaneously, and the robot takes off.
Alberto Comoretto, Study First Author and PhD Student, AMOLF
Complex collective motions occur from simple interactions, such as firefly flashing in synchronization or heart cells beating in unison.
When a flow of air is provided as input, the robot achieves 30 body lengths per second. In comparison, a Ferrari can go “only” 20 lengths every second. This speed is orders of magnitude quicker than other air-powered robots, which usually require centralized control.
Decentralized Intelligence
Even more surprisingly, the synchronization adapts. If the robot encounters a barrier, it reorients itself. When it transitions from land to water, the gait naturally changes from an in-phase hopping rhythm to a swimming freestyle. These transitions occur with no central processor or control logic. Instead, mobility results from the close relationship between body and environment.
In biology, we often see similar decentralized intelligence. Sea stars, for example, coordinate hundreds of tube feet using local feedback and body dynamics, not a centralized brain.
Mannus Schomaker, Study Co-Author and PhD Student, AMOLF
The study questions the traditional wisdom that robots require complex control systems to achieve lifelike behavior.
Simple objects, like tubes, can give rise to complex and functional behavior, provided we understand how to harness the underlying physics.
Bas Overvelde, Principal Investigator, AMOLF
Overvelde prefers not to refer to it as a robot.
“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,” Overvelde added.
How Can This be Applied?
Possible future applications include smart pills and space technology. Safe microrobots without microelectronics that can be ingested and autonomously deliver medications once they reach the target region. Robotic wearing exosuits that sync to walking steps without processors, lowering power usage while increasing human strength.
Autonomous mechanical machines designed for use in harsh conditions, such as space, where ordinary electronics may fail. More broadly, these examples demonstrate how this study opens the door to mechanical systems that behave as if they had a computer, yet do not require one.
The team expects that this study will inspire new ways of thinking about robotic design, such as simpler, more adaptable, and resilient systems. Not by computation or artificial intelligence, but through physics.
Journal Reference:
Comoretto, A. et al. (2025) Physical synchronization of soft self-oscillating limbs for fast and autonomous locomotion. Science. doi.org/10.1126/science.adr3661