Engineers have created a new robot that looks and moves like a worm and could be used by the military in reconnaissance missions.
The meshworm is made from soft materials and is able to squeeze through tight spaces by contracting segments of its body in the same way as an earthworm or a sea cucumber.
It uses an artificial muscle made from nickel and titanium wrapped in a polymer mesh, which stretches and contracts with heat when a small current is applied.
The team, from the Massachusetts Institute of Technology (MIT) and Harvard University, said the robot could be used in the military for navigating rough terrain and for spying.
It is also incredibly resilient. Tests showed that even after being stepped on or hit with a hammer it was still able to function fully.
"You can throw it, and it won't collapse," said Sangbae Kim, a mechanical engineer at the MIT. "Most mechanical parts are rigid and fragile at small scale, but the parts in meshworms are all fibrous and flexible."
Although the engineers have a specific military use for the meshworm in mind, Kellar Autumn, a professor of biology at Lewis and Clark College, thinks shape-changing artificial muscles could begin to emerge in mobile phones, portable computers and even cars in the future.