Researchers from the Massachusetts Institute of Technology (MIT) have developed a new, gel-based type of underwater robot that can kick a ball underwater, catch and release a live fish and perform other high-energy tasks, according to a new Nature Communications study.
The new robots move when water is pumped in and out of them, lead investigator Xuanhe Zhao, an associate professor of mechanical engineering and civil and environmental engineering at the institute, and his colleagues explained in a statement. They are made completely out of hydrogel, a tough, nearly transparent, rubber-like material that is created primarily out of water.
“In this work, we present the world’s first report of a fully hydrogel-made hydraulic actuator with fast and forceful actuation,” MIT graduate student Hyunwoo Yuk, a member of the research team, told Digital Trends. Their design “enables fast and forceful actuation, similar to fishes, for a fully hydrogel-based system which have been not possible” previously.
Also, due to the high water content of the hydrogel, these new robots “are optically and sonically transparent in water like a glass eel in the ocean,” he continued. Water is pumped into a series of hollow hydrogel structures through a series of rubbery tubes, and once completed, the robots can inflate in a variety of different orientations, allowing them to curl up or stretch out.
Technology could be used in surgery, camouflaged devices
The MIT researchers noted that they developed several different types of these hydrogel robots, including one that has a moveable finlike structure, one with an articulated appendage capable of making a kicking motion, and one shaped like a hand that can both clench its fist and relax.
Since hydrogels are biocompatible, meaning that they can interface with human organs without potentially harmful side effects, Zhao said that his team is looking to adapt these robots for use in medical applications. He added that they are currently working with various health organizations to “translate this system into soft manipulators such as hydrogel ‘hands,’ which could potentially apply more gentle manipulations to tissues and organs in surgical operations.”
They aren’t focusing solely on medical uses for their creations, however. “We want to pinpoint a realistic application and optimize the material to achieve something impactful,” Yuk explained. “To our best knowledge, this is the first demonstration of hydrogel pressure-based actuation. We are now tossing this concept out as an open question, to say, ‘Let’s play with this.’”
Some possible uses for the technology, he told Digital Trends, would be to help a heart to beat by applying pressure through the soft and wet hydrogel, or taking advantage of its near-transparency to develop a new type of underwater surveillance robots or other types of camouflaged devices. In addition, the hydrogel robots could be made softer or harder as needed.
However, as Engadget pointed out, the MIT scientists still have a lot of work to do, as they will need to tweak and customize the hydrogen robots before they can be used in any of these types of jobs. The research was partially supported by the Office of Naval Research, the MIT Institute for Soldier Nanotechnologies, and the National Science Foundation (NSF).
Image credit: Hyunwoo Yuk/MIT Soft Active Materials Lab