AILSA CHANG, HOST:
Ordinary people may be one step closer to becoming superhuman. Exosuits are these wearable machines that can make a person faster and stronger. NPR's Merrit Kennedy reports on one new invention and where the technology might be heading.
MERRIT KENNEDY, BYLINE: If you hear the word exosuit, superheroes might come to mind - like Tony Stark, who invents an amazing exosuit and becomes Iron Man.
(SOUNDBITE OF FILM, "IRON MAN")
ROBERT DOWNEY JR: (As Tony Stark) Engage heads up display.
UNIDENTIFIED ACTOR: (As character) Check.
DOWNEY JR: (As Tony Stark) Import all preferences from home interface.
UNIDENTIFIED ACTOR: (As character) Will do, sir.
KENNEDY: One newly designed suit doesn't have all the bells and whistles of Iron Man's. It looks kind of like bike shorts with some wires and small machines around the waist and cables down the legs. And when it's turned on, a person expends less energy when they move.
CONOR WALSH: So essentially, we've kind of, you know, recreated an artificial muscle, you know, on the outside of the human body that's working in parallel with the underlying biological muscle.
KENNEDY: That's Conor Walsh, an engineering professor at Harvard. He describes what it's like to put the suit on.
WALSH: You definitely notice that it's pulling across your joints, so you feel kind of the small tugs from the cable. But after, you know, a fairly short while - say, maybe, like, five minutes - you don't really notice it anymore.
KENNEDY: He says you're just happily running along. And when the suit turns off...
WALSH: You really quickly notice that your legs feel a little bit heavier, and you feel a little bit more sluggish.
KENNEDY: Other exosuits have made it easier to walk or run, but this team says theirs is novel because it can assist people with both kinds of movements. It's been a design challenge because the strides of walking and running are fundamentally different motions, so the machine has to be able to sense when a person changes their gait.
WALSH: So the person doesn't have to tell the system to do anything. It just automatically switches between those two modes.
KENNEDY: In the team's research published today in the journal Science, they found that a person using their suit expended 9% less energy walking and 4% less energy running. Walsh says he thinks the suit could be helpful for a soldier carrying heavy weights over long distances or your average weekend warrior.
WALSH: Helping healthy people move more efficiently - could be, you know, someone who's, you know, a recreational hiker who wants to have a little bit more endurance.
KENNEDY: Other models could help people with medical issues to move more easily. And Walsh's lab is collaborating with a company to sell exosuits for stroke survivors. This latest tight fabric suit looks more comfortable than some of its predecessors made of large and bulky pieces of metal. And Walsh says the exosuit field is changing fast. In the future, he says they may not be exosuits at all, but rather, technology implanted inside a person's body.
Merrit Kennedy, NPR News.