Researchers have finally cut the cord on soft robots. Researchers created an untethered soft robot that can stand up and walk away from its designers.
Researchers in the lab of Robert Wood, the Charles River Professor of Engineering and Applied Sciences were able to scale up earlier soft-robot designs to allow them carry on their back everything they need to operate such as micro-compressors, control systems, and batteries.
"Earlier versions of soft robots were all tethered, which works fine in some applications, but what we wanted to do was challenge people's concept of what a robot has to look like," said Michael Tolley, a research associate in materials science and mechanical engineering at the Wyss Institute and the study's first author. "We think the reason people have settled on using metal and rigid materials for robots is because they're easier to model and control. This work is very inspired by nature, and we wanted to demonstrate that soft materials can also be the basis for robots."
Compared with earlier soft robots, which are usually no larger than a steno pad, the new system is "huge" and can carry seven-and-a-half pounds on its back.
"As soon as you start thinking about putting the basic components you need to make this work -- micro-compressors, controllers, and batteries -- on an untethered robot, you need a design that can carry those parts," Tolley said. "You need to think about something that can handle much higher pressures, so there are materials challenges and there are design challenges and there are control challenges."
The robot is made out of a "composite" silicone rubber made from stiff rubber impregnated with hollow glass microspheres in order to reduce the robot's weight. The robot was tested in snow, submerged in water, walked through flames, and even run over with a car; in each experiment the robot remained unscathed.
The innovations could transform the way robots are used.
"One of the things that limit our imagination is that factory robots are very large and scary and dangerous to be around," he said. "As a lay person, you can't just walk into a factory where industrial robots are working. But a soft system is inherently less dangerous, so you can start to interact with it more, and I think that opens up many more opportunities," Tolley said.
