MIT researchers have developed the RoboClam, a miniature robot that tunnels like a razor clam, with underwater anchoring technology in mind, via BBC.
The device mimics the digging action used by razor clams to turn solid soil into liquid “quicksand”, helping them slide through.
A prototype is described in the journal Bioinspiration and Biomimetics by engineers from MIT in Boston, US.
They set out to design a new low-power, light-weight anchor for autonomous underwater vehicles.
“Luckily, nature had already done the work for us,” said Dr Kerstin Nordstrom, of the University of Maryland, who collaborated on the research.
The answer was poking out of mudflats off the coast at nearby Gloucester, MA.
The Atlantic razor clam, Ensis directus, has been dubbed “the Ferrari of underwater diggers”.
An animal of its modest frame (10-20cm) should only be strong enough to penetrate 2cm into packed sand. But it can burrow up to 70cm in just over a minute.
Compared to existing anchor technology “the razor clam is about 10 times more efficient,” Dr Nordstrom told BBC News.
To dig for half a kilometre, it would only use the energy in an AA battery.
“But when you try plunging the shell into the sand, it doesn’t actually penetrate very far,” said Dr Nordstrom.
“What this shows is the clam must be actively doing something to the ground when it digs.”
RoboClam testing apparatus
The prototype was bulky but RoboClam will be developed into a sleeker unit
To find out the razor clam’s secret, they studied its digging action and modelled it mechanically.
The repeated open-shut of the clam’s valves turned the hard-packed soil around it into quicksand.