DARPA has taken the wraps of one of its most simple and yet revolutionary technologies at DARPATech in Anaheim. Power Swim is a human-powered machine comprising a pair of wide. pivoted foils strapped to the user's calves - and, says DARPA, it literally halves the energy required to swim, making it possible for a swimmer to sustain speeds of 2-2.5 knots - twice what is sustainable today. Power Swim prototypes are being tested by Navy SEAL teams.

Program manager Barbara McQuiston tells Ares that Power Swim emerged from a study of strong swimmers in the animal world, notably penguins and dolphins. As anyone who was a tuna or a shrimp in their past life can tell you, penguins and dolphins are depressingly fast, and moreover burn remarkably little energy.

What DARPA researchers found was that strong swimmers propelled themselves by generating vortices rather than brute-force fin-flapping. The wide foils on Power Swim do the same thing. They are claimed to be seven times more efficient than fins.

Other sources report some customer resistance to the device. "They're used to working hard, and if it doesn't hurt they don't think they're doing the job - but then we say, 'when have you ever swum above two knots?'." Another defense source observes: "SEALs are like Catholic school - if it doesn't hurt it's not good for you."

Power Swim is being readied for production by Deka, the company responsible for the Segway. So far, the military is the first target, with rescue swimmers as well as special operators in mind. However, there's little doubt that the commercial market will be large.

pic credits: DTI, DARPA