PHOTO: MIT

Isaac Asimov, the father of the three laws of robotics, made some startling predictions many years ago about how thet future might look like. He’s been dead on in some respects, however the writer miscalculated how advanced robots would be in 2014 and how integrated these would become in human society. You see, before robots become effectively integrated in society, there are a number of challeges that need to be overcome. Robots need to be more agile, more efficient and, of course, cheaper. The number one demand, however, is for robots to become compliant with human behaviour, something that has proved to be more difficult to attain that thought at first glance.

Imagine robots in your household that are efficient and do their job right, but only to fail in interacting in the most basic way with humans. Constantly bumping into people is a real drag, and can actually be painful. In the case of industrial machinery, where human machine operators often juggle their way through the plant, safety is a huge concern and making robots that can “sense” humans is great challenge at the moment.

One way to achieve this is by mimicking nature. MIT’s Computer Science and Artificial Intelligence Laboratory demonstrates an option for navigating complex environments with their robot-fish. The robot is soft bodied and, as far as mechanics are concerned, it’s as agile and responsive as the real thing.

Biomimetic robots are typically bulky and unreliable. The one made at MIT is different in the sense that it’s soft bodied and completely autonomous, everything being contained inside its body. The “head” is rigid and acts as the nervous center of the robot fish, housing all the primary electronics. Actuators and sensing hardware is located in the rear, made of soft silicone, that can perform sophisticated, agile movements and is safe for operation near humans. A wireless receiver allows a computer to operate the fishrobot remotely.

Andrew Marchese, doctoral candidate in EECS at MIT (right), and Dr. Daniela Rus, professor in EECS and Director of CSAIL, hold a soft robotic fish developed by the Distributed Robotics Laboratory.
Photo: M. Scott Brauer

“Because of their bodies’ capability to bend and twist, these robots are capable of very compliant motion. They’re capable of very rapid, agile maneuvers, which pushes the envelope on what machines can do today,” said Daniela Rus, director of the lab.

“They’re also inherently safe to be around,” she said.

Scientists in robotics have been struggling for a long while to find a perfect balance between rigidity and flexibility, since bulky electronics offer little room for acrobatics. Sure, you can incorporate stretchy electronics and circuitry from the get-go, but the field is still making its first baby steps. Taking inspiration from the commom fish, the MIT robots blends rigidity and flexibility by concentrating them in separate body parts.

Making robots easier to interact with humans

The extremely agile robot fish, as one can witness in the video above, pumps carbon dioxide to move about. Within the fish head are two carbon dioxide canisters, and inside each side of the tail is a long, undulating channel that inflates with carbon dioxide. The canisters in the head each control one side of the tail by opening to different diameters for different durations to produce specific movements. Also, like a real fish, the robot can perform a 100-degree escape turn in about one-tenth of a second.

The maneuver is so fast and it’s got such high body curvature that it shows that soft robots might be more capable in some tasks,” said the fish’s designer, Andrew Marchese, an MIT electrical engineering graduate student.

Obviously, the applications of a robot fish are limited, but you need not work with water necessarily. You can study how a soft body robot behaves in his environment, then a adapt to a new one with the experience you gain elsewhere. For instance, if a better understanding of soft bodied robots is attained, which granted are rather unpredictable, you can design industrial or household robots that have much wider degree of freedom of motion. The MIT researchers next plan on improving their current model, since the CO2 canisters allow only 25 escape maneouvers to be made before the gas runs out, by using water instead.

The robot fish was described in a paper published in the journal Soft Robotics.