Robots could use living invertebrates as grippers to help them pick up awkward objects or grasp things underwater.
“We don’t mean it as a replacement for robotics, but as a kind of new direction or new way to do both biology and robotics,” says Josephine Galipon at Tohoku University in Japan.
But others have questioned how useful or ethical this approach is.
Galipon and her colleagues have now made grippers using pill bugs – a kind of woodlouse – and chitons – marine molluscs that can stick firmly to rocks, like a limpet.
The team made custom 3D-printed housings for both organisms and attached them to a robot arm. The pill bugs picked up and rotated a piece of cotton wool for around 2 minutes before releasing it. The chitons picked up cork, wood and plastic cylinders underwater, but didn’t easily release the objects.
While the release mechanisms will need to be developed further, the chiton’s ability to pick up cork and wood is promising, as it is a difficult task for the suction cups that are conventionally used in underwater robotic grippers, says Galipon.
It is a novel approach, says Steve Davis at the University of Birmingham, UK, but it is unclear what tasks the insects would be able to perform that current robotic grippers can’t. “It’s different, but what’s it trying to address?” he says.
Galipon didn’t specify what tasks the grippers would be useful for, saying: “To go to the next stage in robotics, we perhaps need to stop putting labels on things.”
There are also “all sorts of ethical questions around this work”, says Davis, particularly if researchers were to start trying to control when the animals grip and release objects.
Galipon says the animals weren’t harmed; after the experiment, the pill bugs were released back into the wild and the chitons continued to live in a water tank. “Especially for sentient animals, we would like to establish a kind of mutual interaction with a cooperative relationship,” says Galipon. “It’s a little bit different from domestication, but just a cooperation, where the animal can then go about its day.”