MIT scientists create “robofin” for future submarines

MIT scientists are taking a cue from nature and are developing a robotic fin that could be used on future submarines. The fin is made of thin, flexible polymer that curls up when electric current is applied. The scientists say the fin could one day replace traditional submarine propellers and make underwater craft more energy efficient.

The research is being spearheaded by MIT professor Ian Hunter and post-doctoral student James Tangorra in the Bioinstrumentation Lab. These scientists chose to copy the movements of the bluegill sunfish because it has constant forward thrust without any backward drag. They broke the motion down to 19 critical elements include sweeping and curling of various parts of the fin.

So far the scientists can copy all the motions, but the tricky part is getting all the motions in sequence. Of course you just can’t attach a robotic fin to the back of a rigid body submarine because regular fish move their entire bodies, along with their side fins. Tangorra said his team will examine the sunfish’s entire motion and to figure out how to “best adapt nature’s principles to designing robotic vehicles.”