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Mutant Quadrotor MAV Lifts Off After a Century of Development

If you take a quadrotor and bend all the motors out 90 degrees and all the rotors out 90 degrees more, you wouldn’t think it would fly. But it does

2 min read
Mutant Quadrotor MAV Lifts Off After a Century of Development

Micro Air Vehicles (MAVs) are way, way more useful if they can hover. Hovering capability allows MAVs to operate indoors, and to make it happen, you have to rely on platform like a helicopter (or a quadrotor) or something moreexotic. This thing definitely falls into the “more exotic” category—it’s called a cyclogyro, or cyclocopter.

Fundamentally, a cyclocopter is similar to a helicopter in that it creates lift through rapidly moving airfoils. Unlike a helicopter, a cyclocopter’s airfoils rotate around a horizontal axis, continually changing their pitch in order to generate thrust in one single direction:

It’s certainly not a simple system, which is why this idea (which has been around in the form of various prototypes for nearly a century) only got off the ground to make a first untethered flight just recently, thanks to a lot of hard work from Moble Benedict and his team at the University of Maryland. They’ve been developing a cycloidal rotor system made of carbon fiber and titanium that’s so far been applied to both a quad cyclocopter and a twin cyclocopter, and they’ve successfully gotten the two rotor version (with a supplemental tail rotor) into an untethered and more or less stable hover:

You’re probably wondering what the advantages of such a complex system are, and luckily, there are a few. Primarily, it's suggested that a cyclocopter would be more efficient than a helicopter, able to generate more thrust for a given amount of power. It’s also thought that cyclocopters will prove to be more maneuverable, since the thrust can be vectored very rapidly. On the downside, you’ve got the overall complexity of the system to deal with, and the weight of the rotors might cancel out any efficiency gains.

There are definitely a lot of questions about the feasibility of a design like this, but in order to figure it out, the best thing to do is just build them and see what happens, and from the sound of things, the UMD team is finally cashing in on about a century worth of speculation.

[ Paper (*.PDF) ] Via [ UMD ]

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The Bionic-Hand Arms Race

The prosthetics industry is too focused on high-tech limbs that are complicated, costly, and often impractical

12 min read
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A photograph of a young woman with brown eyes and neck length hair dyed rose gold sits at a white table. In one hand she holds a carbon fiber robotic arm and hand. Her other arm ends near her elbow. Her short sleeve shirt has a pattern on it of illustrated hands.

The author, Britt Young, holding her Ottobock bebionic bionic arm.

Gabriela Hasbun. Makeup: Maria Nguyen for MAC cosmetics; Hair: Joan Laqui for Living Proof
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In Jules Verne’s 1865 novel From the Earth to the Moon, members of the fictitious Baltimore Gun Club, all disabled Civil War veterans, restlessly search for a new enemy to conquer. They had spent the war innovating new, deadlier weaponry. By the war’s end, with “not quite one arm between four persons, and exactly two legs between six,” these self-taught amputee-weaponsmiths decide to repurpose their skills toward a new projectile: a rocket ship.

The story of the Baltimore Gun Club propelling themselves to the moon is about the extraordinary masculine power of the veteran, who doesn’t simply “overcome” his disability; he derives power and ambition from it. Their “crutches, wooden legs, artificial arms, steel hooks, caoutchouc [rubber] jaws, silver craniums [and] platinum noses” don’t play leading roles in their personalities—they are merely tools on their bodies. These piecemeal men are unlikely crusaders of invention with an even more unlikely mission. And yet who better to design the next great leap in technology than men remade by technology themselves?

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