When you think of a robot, the first thing to come to mind is usually metal and hard plastic. But these materials don't exactly have a delicate touch, so scientists are increasingly turning to soft components to craft more nimble bots that can manipulate fragile objects and more easily navigate unpredictable environments. But, as The Los Angeles Times’ Amina Khan reports, there is often one major drawback to these soft robots: “They’re not exactly powerlifters,” she writes.
Now, researchers at the Massachusetts Institute of Technology and Harvard University have created artificial muscles that combine the best of both worlds, Khan reports. Though the creations are soft around the edges, they can lift up to 1,000 times their own weight. The researchers describe their work in a recent article published in the journal Proceedings of the National Academy of Science.
The artificial muscles are composed of folded structures sealed in polymer skin, sporting bends and wrinkles like unfolded pieces of origami. Internal structures guide the movement of the polymer skin and are composed silicone rubber or even stainless steel shims.
To operate the device, a vacuum draws out the air or fluid of the sealed structure, causing its shape to shrink and morph. The internal structural folds "program" the artificial muscles' movements, causing them to shorten, curl, bend and even twist. Some of the devices can shrink to a tenth of their original size.
The origami techniques use few materials and simple processes, which allows the researchers to produce complex designs at a low cost. On average, the devices can be constructed in less than 10 minutes and the materials cost less than a dollar, reports Darrell Etherington for Tech Crunch.
The technology could be used for everything from daily tasks, like picking up grapes, to precision procedures, like surgical repair work inside of our bodies, Kahn writes. “What we want are soft, safe, compliant robots that have strength, that have the properties that are now achievable with hard-bodied systems,” roboticist Daniela Rus, director of MIT’s Computer Science and Artificial Intelligence Laboratory and one of the study’s senior authors, tells Kahn.
The new artificial muscles are not the first softbots. In 2016, researchers announced the creation of the first entirely soft octopus-shaped robot, dubbed "Octobot," Erin Blakemore wrote for Smithsonian.com at the time. And there have been many other partially-soft bots. Still, the current device is unique in its combination of strength and flexibility.
Rus tells Kahn said the team’s next effort could be a human-scale version of the design.