Credit: Cornell University
Imagine tiny robots moving together in perfect harmony, like a stadium crowd doing the wave.
Researchers at Cornell University have created microscopic machines that can synchronize their movements using electronic pulses.
This groundbreaking work could lead to new uses for microrobots in medicine, environmental cleanup, and even advanced materials.
The research, published on November 27 in [_Science Robotics_](https://doi.org/10.1126/scirobotics.adn8067), is the first to show that micromachines equipped with tiny electronic systems, called complementary metal-oxide-semiconductor (CMOS) oscillators, can coordinate themselves without any central control.
These findings were led by Alyssa Apsel, director of Cornell’s School of Electrical and Computer Engineering, and Itai Cohen, professor of physics.
Each tiny robot has a thin paddle, just 7 nanometers thick, that bends and flexes like a person standing and sitting during a stadium wave.
These machines communicate with each other by sending electronic signals that adjust their timing, so they all move together.
This process doesn’t need any complex wiring or external control. Instead, the robots naturally align with the fastest-moving oscillator in the group.
“The oscillators use very little power and are simple to operate,” said Apsel. “This makes them perfect for tiny machines that can’t rely on big, complicated systems to communicate over long distances.”
The inspiration for this synchronization came from nature. Similar processes can be seen in fireflies that flash in unison and heart cells that beat together.
Using a method called “pulsed coupling,” the microrobots can send and receive signals to stay in sync, even if some of them get separated or disturbed. If groups of robots reconnect after being split, they can automatically synchronize again.
The researchers successfully tested groups of up to 16 microrobots moving in both straight lines and two-dimensional patterns.
They believe this method can easily be scaled up to larger swarms, which opens up exciting possibilities. For example, these robots could deliver drugs to specific parts of the body, mix chemicals efficiently, clean up environmental spills, or even build tiny structures.
“It’s also a step toward creating ‘elastronic materials,’ where electronics are embedded into materials to create behaviors not found in nature,” Cohen explained.
In the future, the researchers aim to create more advanced robots that mimic movements like inchworms or can split into smaller, independent pieces.
“Designing tiny machines that can move and sense their environment has been a challenge, especially when it comes to getting them to work together,” said Apsel. “But by taking inspiration from nature, we’ve shown how collective behaviors can emerge in these systems.”
This study was supported by the National Science Foundation, the U.S. Army Research Office, and other organizations. It highlights how lessons from biology can be applied to engineering for innovative solutions.
_Source: Cornell._