Toss aside your typical idea of a robot — all metal, jerky movements and a stiff-legged walk.
Scientists at Tufts University are developing soft, squishy robots that are able to squeeze into spaces a fraction of their normal size and then morph back into their original size and shape. And they plan on replacing the synthetic materials used to make them with biological materials so the robots would be biodegradable, too.
Creating soft robots would mean a whole new way of looking at robotics, according to Barry Trimmer, the Henry Bromfield Pearson Professor of Natural Sciences at Tufts and co-principal investigator on the project.
"Most machines are made out of stiff materials," he says. "They're great if you want to move things around because you can make joints and hinges and wheels. A lot of animals, though, don't have hard parts — like bones or skeletons. We suddenly realised that these things can control their bodies without them but there was no theory on how soft things can be controlled and moved.... We want to learn from the animal how to do that and how to engineer that."
Using biological materials such as silk proteins to make muscles and sensory organs, the robots could be used for landmine detection and search-and-rescue efforts in hazardous conditions.
"We hope our technology will help us create more adaptable robots that can manage in different situations," says Trimmer. "Robots might be good working in a building or on a road but they're generally not good at walking in the woods or climbing trees or walls."
To develop the technology needed to build squishy robots, Trimmer and his fellow scientists are looking to squishy creatures in nature such as the octopus and the caterpillar.
Researchers have spent a lot of time studying the caterpillar because — even without bones or joints — it can control its body with a relatively simple nervous system. Part of the genius behind the caterpillar is that with no joints and only two muscles controlling each leg, it largely can move itself around because of the way its body responds to the muscles simply contracting and releasing in the legs.
"We imagine that the way the material bends and the way it responds to forces is part of the computation of the movement," says Trimmer. "The way things swing would make it work properly."
And to control those movements, Trimmer said researchers are working on creating a tiny, flexible computer chip. "The idea is that instead of having a supercomputer to control these very complicated soft structures, we think you can build the computation into the material and the structure," he says. "If you look at a soft-bodied animal, in a traditional engineering approach, you'd expect to use more computation to control it. It should have a bigger brain but you don't see that. There's not that much difference between the brain in the soft caterpillar and the moth or butterfly it becomes, which has a skeleton. It doesn't need a supercomputer."
Meanwhile, researchers at Norwegian firm the Sintef group are working on a robot based on snakes, which could be used to inspect and clean industrial pipe systems.