During a 2014 talk on his exploration of deep-sea coral reefs, Baruch College marine biologist David Gruber showed a video of clunky robotic hands collecting fragile specimens of coral and sponges from the ocean floor. Harvard engineer and roboticist Robert J. Wood was in the audience -- the two scientists were being recognized as Emerging Explorers by the National Geographic Society - and a lightbulb went off.
"They were using rigid Jaws of Life-type grippers designed for the oil and gas industry that were totally overpowered and were destroying things," Wood recalled. "It immediately clicked that there was a soft robotics solution that may be viable."
In the months that followed, the pair collaborated to design, fabricate, and test soft robotic grippers for deep-sea collection of fragile biological specimens. Their recent expedition to the Gulf of Eilat in the northern Red Sea, a unique marine ecosystem that houses one of the world's largest and most diverse coral reefs, marked the first use of soft robotics for the non-destructive sampling of fauna from the ocean floor.
The new technology could enhance researchers' ability to collect samples from largely unexplored habitats thousands of feet beneath the ocean surface, areas that scientists believe are biodiversity hot spots teeming with unknown life. The soft grippers also could be useful in underwater archaeology.
As described in a paper published in the journal Soft Robotics, the team successfully developed two types of grippers, and in the process demonstrated a new fabrication technique that allows for the rapid creation of soft actuators.
Gruber, associate professor of biology and environmental science at Baruch College of the City University of New York, and research associate with the American Museum of Natural History, explores deep ocean ecosystems, with a particular focus on organisms that display bioluminescent and biofluorescent traits. (Bioluminescent animals produce their own light; biofluorescent animals absorb light and re-emit it as a different colour.)
When he wants to visit a coral reef below the maximum depth that human divers can tolerate, Gruber must rely on a remotely operated vehicle (ROV). But there's a problem: the standard-issue robotic "hands" of underwater ROVs are ill-suited to collecting delicate coral, sponge and other samples. That's because the equipment was designed for undersea construction and to install and repair submerged pipelines.
Manipulating and grasping fragile organisms from the sea floor requires something that can mimic the dexterity and soft touch of a human diver's hand. Wood, Charles River Professor of Engineering and Applied Sciences at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) and founding core faculty member of the Wyss Institute for Biologically Inspired Engineering at Harvard University, recognised that soft robotics is tailor-made for the task.