Jet-Propelled Swimming Creatures Could Inspire Deep-Sea Robots

A team from the University of Oregon (UO) has found that the corkscrew-shaped jet propulsion swimming method used by a type of sea creature could inspire new designs for underwater vehicles.

The team used specialized 3D underwater cameras to observe salps, small jellyfish-like animals, as they swam from the ocean floor to the surface off the coast of Kailua-Kona, Hawaii.

“The largest migration on the planet happens every single night – the vertical migration of planktonic organisms from the deep sea to the surface,” said Kelly Sutherland, lead researcher. 

“They’re running a marathon every day using novel fluid mechanics. These organisms can be platforms for inspiration on how to build robots that efficiently traverse the deep sea.”

The team used imaging and recordings to collect data on the creatures’ swimming techniques and identified two modes. In one, the salps spun around an axis, akin to a spiraling football and in the other longer chains used jet propulsion to corkscrew through the water.

Some existing microbots already take design inspiration from underwater animals, but the UO team said its discovery paves the way to create larger underwater vehicles.

The team researchers concluded that it may be possible to create silent, less turbulent robots modeled after these efficient swimmers and a multijet design may use less energy.

Related:Autonomous Underwater Robot Cleans Ships, Improves Sustainability

“It's a study that opens up more questions than provides answers,” Sutherland said. “There's this new way of swimming that hadn't been described before, and when we started the study we sought to explain how it works. But we found that there are a lot more open questions, like what are the advantages of swimming this way? How many different organisms spin or corkscrew?”

Further research into how this swimming method could be applied to vehicles is ongoing, conducted in collaboration with Louisiana Universities Marine Consortium, University of South Florida, Roger Williams University, Marine Biological Laboratory and Providence College.