Researchers at the Massachusetts Institute of Technology (MIT) have long been at the forefront of soft robotics, so much so that they have created their own journal for the topic, Soft Robotics, the debut issue of which is out this month. This first installment profiles the creation of the first self-contained, autonomous soft robot capable of rapid body movement.
Taking the form of a fish, the robot can execute escape maneuvers in just a fraction of a second—almost as quickly as real fish can—by convulsing its body. Built around a rigid core enclosing the robot fish’s “brains” is a soft, flexible, silicon rubber casing. Each side of the robot’s tail section contains a long, tightly undulating channel, and releasing carbon dioxide from a canister in the fishbot’s abdomen inflates these channel independently, bending the tail in the opposite direction of the inflation.
Designed and built by MIT Department of Engineering graduate student Andrew Marchese using 3D printing technology, the fish can perform between 20 to 30 maneuvers before running out of gas. Standard swimming motions also deplete the CO2 supply. “[It] was designed to explore performance capabilities, not long-term operation,” Marchese said of his fishbot.
A new, improved version of the fish is in the works, one that utilizes pumped water rather than gas canisters to create movement—this should allow the robot to operate for up to 30 minutes at a time. It would otherwise use the same body design and propulsion principles.
Soft Robotics’ piece on the fish was authored by Marchese, Daniela Rus, a professor of computer science and engineering and director of MIT’s Computer Science and Artificial Intelligence Laboratory, and postdoctoral scholar Cagdas D. Onal. Rus hypothesizes that, with further updates, the fish robot could be used to swim among schools of real fish to better study their behavior in their natural habitat.
The creation of the fishbot is part of MIT’s ongoing wider research into soft robotics, a key field of further study. This research suggests that soft robots could ultimately be more useful and versatile than “traditional” robots in some applications, specifically where it’s important to avoid damage—either to the robot or to what it’s studying—caused by collisions or impact.
“As robots penetrate the physical world and start interacting with people more and more, it’s much easier to make robots safe if their bodies are so […] soft that there’s no danger if they whack you,” Rus said. “In some cases, it is actually advantageous for these robots to bump into the environment, because they can use these points of contact as a means of getting to the destination faster.”
MIT’s fish robot is also one of the first completely self-contained soft robots (not tethered to an external “brain” housing) that is capable of performing advanced, high-performance actions.
• “Soft Robotic Fish Moves Like the Real Thing” http://web.mit.edu/newsoffice/2014/soft-robotic-fish-moves-like-the-real-thing-0313.html
• “Fish’n’microchips: MIT’s Soft Robotic Fish Swims ‘Like the Real Thing’” http://www.theguardian.com/technology/2014/mar/14/mit-soft-fish-robot-swimming
• “MIT Builds A ‘Soft Robotic’ Fish That’s Perfectly Cuddly, Moves Like the Real Thing” http://techcrunch.com/2014/03/13/robot-fish/