If an autonomous fish robot recently developed at MIT finds itself about to run into an obstacle, it convulses its body to switch directions at the last second, just like a real fish.
Its secret? It is made of soft silicone rubber and powered by fluid that shoots through vein-like channels in its body, giving it the ability to move faster and more freely than more traditional “hard” robots.
“The fact that the body deforms continuously gives these machines an infinite range of configurations, and this is not achievable with machines that are hinged,” MIT Computer Science and Artificial Intelligence Laboratory director Daniela Rus said in a release Thursday. “A rigid-body robot could not do continuous bending.”
Soft robots are also much less dangerous to people and their surroundings, which means they do not have to be as careful about avoiding collisions. Rigid robots need to carefully plan routes that avoid any obstacles, which can be inefficient and slow. This fish can bump into walls if it means it will get to its destination more quickly.
The fish is controlled by a pack of electronics contained in a waterproof casing in its belly. A canister can release carbon dioxide into a channel that runs through the robot’s tail. Inflating and deflating the channel causes the fish’s tail to whip back and forth, propelling it in different directions. The research team was able to get the fish to take turns as sharp as 100 degrees.
The team is now working on a new fish that will use water instead of carbon dioxide for propulsion. The new fish will also be able to swim for up to 30 minutes, while the current model can only perform 20 to 30 turns before exhausting its supply of fuel. Rus believes that robot fish could someday swim with schools of live fish to collect data.