A Water-Driven Actuator Inspired by Sea Cucumbers Could Be the Future of Soft Robotics
Built from mutable collagenous tissue (MCT), just like the sea cucumber, this actuator dramatically outperforms the competition.
A team of researchers from the Pohang University of Science & Technology (POSTECH) have turned to an unlikely inspiration for a high-performance programmable actuator: sea cucumbers.
Sea cucumbers, the researchers explain are made of mutable collagenous tissue (MCT) that is soft and can stiffen, shrink, and stretch — and even be returned to its original shape after death by simply adding water. It's this ability the researchers have replicated in a programmable, high-performance robotic actuator — which is driven by water.
"The soft robot activates when it comes in contact with moisture and is flexible and deformable to easily adapt to various environments," says Dong Sung Kim, professor at POSTECH, of the team's work. "This newly developed hydrogel actuator is very powerful and actuates quickly to enable operation even in places without electricity by using chemical energy."
Made from a readily-available hydrogen, the prototype actuator readily outperforms rival water-actuated designs offering a force 200 times greater and 300 times faster, at two newtons and 1/3 of a second respectively. It can operate in a wide range of temperatures, works just as well under the water as above it, and is robust enough to return to its original shape even at 300 per cent of its tensile strain.
The team is hoping to produce the actuator for use in a range of fields including industrial and biomedical, where it could drive robot arms, prosthetic hands, and even help to close wounds.
The team's work has been published under closed-access terms in the Journal of Materials Chemistry A.