A childhood toy may hold the secret to future smart robots and mechanical computers.
Scientists have developed a new way to program special materials simply by spinning them, inspired by the same snapping motion that makes slap bracelets so satisfying.
The research, published in Science Advances, could help create future soft robots, medical devices, and smart materials that store information directly within their physical structures instead of relying on electronics.
The work was carried out by researchers from EPFL, the Dutch research institute AMOLF, and Leiden University.
The idea centers on structures known as “bistable” materials. These materials can exist in two stable positions, similar to how a slap bracelet can remain either straight or curled.
Scientists use these two positions to represent digital information, much like the 0s and 1s used in computers. These physical forms of data storage are called mechanical bits, or “m-bits.”
For years, engineers have tried to build programmable metamaterials—special materials with structures designed to perform useful tasks.
But one major problem remained: each mechanical bit usually had to be controlled one by one, making the process slow and complicated.
The new study introduces a much simpler solution. Instead of controlling each bit separately, the researchers found they could program many bits at once by spinning the entire system.
By carefully adjusting the speed, direction, and acceleration of a rotating platform, the team used forces created during rotation to make elastic beams snap from one stable position to another.
These forces include centrifugal force, which pushes objects outward during spinning, along with other rotation-related forces.
According to Pedro Reis, who leads the Flexible Structures Laboratory, the method allows researchers to globally control the “memory” of a mechanical system using rotation alone.
To demonstrate the technique, the scientists programmed all 26 uppercase letters of the alphabet using only five small silicone beams mounted on a spinning platform. Each letter was converted into a binary code using the standard ASCII computer encoding system.
The researchers adjusted each beam so it would flip at different spinning conditions. Depending on the rotation settings, some beams snapped while others stayed in place. Together, the final beam positions formed the binary patterns representing different letters.
The researchers say recent advances in high-torque motors made this approach possible because modern motors can now control spinning movements with extremely high precision.
The team believes the technology could eventually lead to smart systems that work without electronics. For example, tiny medical devices could use spinning forces to control miniature valves that guide liquids through diagnostic systems. Soft robots could also use bistable joints that respond to changes in air or water pressure, allowing them to move without onboard computers or circuits.
The researchers say their new “dynamic driving” method could open the door to remotely controlled smart materials for use in medicine, underwater robotics, implants, and future mechanical computing systems.
Source: EPFL.
