Our future robot overlords never looked so squishy. A team of scientists led out of Harvard University have managed to build an entirely soft robot — one that's inspired by an octopus.
The octobot, described this week in the journal Nature, could pave the way toward more effective soft robots that could be used in search and rescue, exploration and to more safely interact with humans.
"The octobot is a minimal system designed to demonstrate our integrated design and fabrication strategy," the study authors wrote, "which may serve as a foundation for a new generation of completely soft, autonomous robots."
Traditionally, robots have been seen as stiff, angular entities, made of metal and other rigid materials (think C-3PO in Star Wars). But there's a good historical reason for that, scientists say.
"Robots are typically used in manufacturing contexts that involve well-structured environments," Barbara Mazzolai and Virgilio Mattoli of the Italian Institute of Technology's Center for Micro-BioRobotics, who were not involved in the study, wrote in a commentary. "These situations allow them to move following predefined procedures, limiting interactions with human operators for safety reasons."
But if you take these robots out of factories and put them in real world, things start to get dicey. Robots built for precise, repetitive movements in a controlled environment don't do so well on rough terrain or changing conditions. And they aren't especially safe around humans, because they're made out of hard parts and can't accurately adjust the force they wield on much-more-pliant people.
But building a completely soft robot has remained a challenge, because even if engineers can build a silicone body, they still had trouble building soft versions of certain essential parts, such as the control system and the power source.
"Creating a new class of fully soft, autonomous robots is a grand challenge, because it requires soft analogues of the control and power hardware currently used," the study authors wrote.
But for this paper, researchers from Harvard's Wyss Institute for Biologically Inspired Engineering managed to do just that. Octobot's eight arms move thanks to a pneumatic system of inflatable compartments. The moving parts are connected to a network of channels that send liquid fuel (a hydrogen peroxide solution) to mix with a platinum-based catalyst in certain reaction chambers. As the fuel decomposes, it releases pressurized oxygen that inflates the actuators, allowing the octobot to move.
These movements are controlled by a series of logic gates — basically a fluid-filled version of a circuit board. The scientists managed to create this complex system using several techniques, including soft-lithography and multi-material embedded 3D printing.
Octobot is just the first step toward creating more advanced and capable robots, researchers said; its capabilities are pretty limited. But designing and building more complex robots will mean integrating several different materials and improving many different abilities, including movement, power and control and octobot shows that it can be done.
"Although soft robotics is still in its infancy, it holds great promise for several applications, such as servicing and inspecting machinery, search-and-rescue operations, and exploration," Mazzolai and Mattoli wrote. "Soft robots might also open up new approaches to improving wellness and quality of life."
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