Researchers from Harvard University and Baruch College at CUNY say their new “ultragentle” gripper device, with its noodle-like fingers, can grab delicate ocean creatures that formerly would have been mangled as scientists pulled them out of the ocean to examine them.
But don’t just take their word for it.
Ask the jellyfish at the New England Aquarium, where resarchers tested the device, pulling moon jellies, jelly blubbers, and spotted jellies, all about the size of a golf ball, from the water without causing them any stress.
The tool could come in handy studying deep sea creatures in their natural habitat, researchers said.
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Jellyfish and squid that live a mile or two underwater are beyond the range of scuba-diving scientists, who must rely on submarines to explore the pitch-dark depths. Once in a while, detritus samplers and other collection tools attached to submersibles can capture the diaphanous animals. But the creatures are at risk of getting stuck in the sampler or destroyed.
The sampling tools available to marine biologists were largely developed for the oil and gas industry and are more suited to grabbing rocks or heavy equipment than sea creatures, researchers said.
The new tool was developed by researchers at Harvard’s Wyss Institute for Biologically Inspired Engineering and John A. Paulson School of Engineering and Applied Sciences (SEAS) and Baruch College at CUNY. The research is detailed in a paper published last week in Science Robotics.
“Our ultragentle gripper is a clear improvement over existing deep-sea sampling devices for jellies and other soft-bodied creatures that are otherwise nearly impossible to collect intact,” first author Nina Sinatra, a former graduate student at the Wyss Institute who is now a mechanical and materials engineer at Google, said in a statement from the university.
“This technology can also be extended to improve underwater analysis techniques and allow extensive study of the ecological and genetic features of marine organisms without taking them out of the water,” she said. “Overall, our ultragentle gripper demonstrates an improvement in gentle sample collection compared with existing deep-sea sampling devices.”
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David Gruber, a marine biologist at CUNY, told The New York Times, “I always felt that it was a little strange for me as a marine biologist to have to kill the animals that I love and study.”
The gripper has six fingers. Each finger is composed of thin strips of silicone with a hollow channel inside. The inside edges of the fingers have a stiffer nanofiber coating that controls how they curve. They are attached to a 3D-printed rectangular palm in such a way that they can be removed individually and replaced if they start to become arthritic.
A switch at the back of the gripper fills the channels inside the silicone fingers with water, forcing them to curl shut in the direction of the nanofiber coating. This helps maintain an ultragentle grip; the fingers exert less than one-10th of the pressure that a human eyelid exerts on the eye.
Current soft marine grippers exert many times more force, researchers said.
Gruber and Wyss founding core faculty member Rob Wood are collaborating on innovations in the use of soft robotics for underwater sampling.
“Soft robotics is an ideal solution to long-standing problems like this one across a wide variety of fields, because it combines the programmability and robustness of traditional robots with unprecedented gentleness thanks to the flexible materials used,” Wood said in a statement.
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Researchers said they first tried the gripper out on an artificial silcone jellyfish in a tank of water. In the New England Aquarium test on real jellyfish, the animals, which are 95 percent water, were unable to break free until the gripper was depressurized.
The team is continuing to refine the gripper’s design and aims to look more deeply into the jellyfishes’ physiological response to being grabbed, to more definitely prove that the animals are not being stressed, researchers said.
Material from The New York Times was used in this report.