The human arm can perform a wide range of extremely delicate and coordinated movements, from turning a key in a lock to gently stroking a puppy’s fur. The robotic “arms” on underwater research submarines, however, are hard, jerky, and lack the finesse to be able to reach and interact with creatures such as jellyfish or octopuses without damaging them.
Previously, the Wyss Institute for Biologically Inspired Engineering at Harvard University and collaborators developed a range of soft robotic grippers to more safely handle delicate sea life, but the devices still relied on hard, robotic submarine arms that were difficult to maneuver into various positions.
Now, a new system built by scientists at the Wyss Institute, Harvard’s John A. Paulson School of Engineering and Applied Sciences (SEAS), Baruch College, and the University of Rhode Island (URI) uses a glove equipped with wireless soft sensors to control a modular, soft robotic “arm” that can flex and move with unprecedented dexterity to grasp and sample fragile creatures. The research is published in Scientific Report.
“This new soft robotic arm replaces the hard, rigid arms that come standard on most submersibles, enabling our soft robotic grippers to reach and interact with sea life with much greater ease across a variety of environments and allowing us to explore parts of the ocean that are currently understudied,” said first author Brennan Phillips, an assistant professor at URI who was a postdoctoral fellow at the Wyss Institute and SEAS when the research was completed.
The apparatus Phillips and his colleagues developed features bending, rotary, and gripping modules that can be added or removed easily to allow the arm to perform different types of movements — a significant benefit, given the diversity of terrain and life in the ocean. Other improvements over existing soft manipulators include a compact, yet robust, hydraulic control system for deployment in remote and harsh environments. The whole system requires less than half the power of the smallest commercially available deep-sea electronic manipulator arm, making it ideal for use on manned undersea vehicles, which have limited battery capacity.