Researchers at MIT have created the most advanced robotic fish built to date.
SoFi, short for “Soft Robotic Fish,” is 18.5 inches long, weighs 3.5 lbs. and can swim up to 60 feet underwater for about 40 minutes at a time. Just like a real fish, it features a torpedo-like shape and undulating tail.
“When we were designing the robot, we tried to make sure that it's moving to conserve the life we're trying to observe,” study co-author Joseph DelPreto told National Geographic.
The MIT team has been working on a robotic fish prototype since 2014, but SoFi is the first version that can not only be controlled remotely but can swim deeper than 3 feet. Given its lifelike appearance, SoFi can get closer to marine creatures than any previous underwater vehicle, allowing scientists to gain potentially unprecedented access to the lives of underwater creatures in endangered environments such as coral reefs.
“Remotely operated vehicles (ROVs) or autonomous underwater vehicles (AUVs) in ocean environments typically use propellers or jet-based propulsion systems,” reads the MIT report. “However, these propulsion systems generate substantial turbulence and have the potential to scare marine life and prevent close-up observations. Further, the mere appearance of these vehicles, typically large and rigid like a submarine, does not integrate well into the marine environment.”
In a video produced by MIT’s CSAIL (Computer Science and Artificial Intelligence Laboratory), the division that created SoFi, the fish can be seen undulating through the Rainbow Reef off the coast of Fiji, the only immediate clues that it’s not perhaps a small shark or tuna being the robot’s constant, repetitive movements and stationary front fins.
“I was amazed at how well it was working, how well I was able to get this tail to beat back and forth or swim left and right, like a shark or some other fish,” Robert Katzschmann, a graduate student at MIT who led the team, told The New York Times.
SoFi’s tail moves with the assistance of a hydraulic pump, controlled by — of all things — a waterproofed Super Nintendo controller. The fish also sports a camera, two-way underwater microphone, battery, environmental sensors and bespoke communication system that relies on sound waves to communicate with SoFi’s diver pilot.
“Our primary goal was to make something for biologists,” said Katzschmann.
The researchers hope that someday an entire fleet of SoFis can help scientists learn more about sea creatures and environments under threat from climate-change-related phenomena like coral bleaching, increased tropical storm activity and rising sea temperatures. Because many of SoFi’s components were created using 3-D printing, researchers are optimistic about the robot’s ability to be cloned.
“In the future, researchers could use the soft robotic fish described in this paper and easily change its size, color, and shape to emulate various types of fish with different dynamic behaviors…. [it] can also be rapidly fabricated to create a swarm of robotic fish,” reads the study. “Such a swarm could enable studies of schools of fish and their interactions in the presence of varying ocean dynamics.”
