Imma Perfetto
Cosmos science journalist
Robots traversing lifting and guiding objects. Credit: Device, Yang and Won
Nanoengineers have designed tiny magnetic robots that swarm together like ants to pick up objects many times their size or even form rafts to float on water.
The researchers think they could be used to tackle difficult tasks in challenging environments, such as offering a minimally invasive treatment for clogged arteries.
Each cube-shaped microrobot stands only 600 microns tall (0.6mm) and is made of an epoxy body embedded with particles of ferromagnetic neodymium-iron-boron (NdFeB).
This means they don’t require batteries or sensors to interact with each other. Instead, they assemble through magnetic attractions and respond to and be guided by magnetic fields.
The researchers controlled the robots using a magnetic field generated by rotating two connected magnets. By varying the angle at which the robots were magnetised, they could programme the swarm to come together in different configurations.
Swarms climbed an obstacle 5 times higher than the body length of a single microrobot and hurled themselves, one by one, over an obstacle. They transported cargo 350 times heavier than each individual robot and could unclog tubes that resembled blocked blood vessels.
A large swarm of 1,000 microrobots formed a raft that floated on water and wrapped itself around a pill, ferrying it through the liquid.
They could even be used to guide the movements of an ant, a slater (known in some places as a pill bug), and a superworm.
“While the study’s results are promising, the swarms will need higher levels of autonomy before they will be ready for real-world applications,” says Jeong Jae Wie of Hanyang University in South Korea.
“The magnetic microrobot swarms require external magnetic control and lack the ability to autonomously navigate complex or confined spaces like real arteries,” he says.
“Future research will focus on enhancing the autonomy level of the microrobot swarms, such as real-time feedback control of their motions and trajectories.”
The research appears in the journal Device.
