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Quadcopter Free-Fall Testing From 4,000 Feet Is Destructive Fun

What happens when you drop a quadcopter from thousands of feet up?

1 min read
Quadcopter Free-Fall Testing From 4,000 Feet Is Destructive Fun

What happens when a quadrotor loses power a few thousand feet in the air and plummets back to Earth? I have no idea. You probably have no idea. But someone has a very, very good idea, because they've done some experimenting. RcTestFlight built a quadrotor, slapped a camera on it, sent it up to over 4,000 feet (1,220 meters), and then cut the motors just to see how it fared.

Quadcopters, like anything else, tend to fall like rocks when they lose power in the air. Unlike rocks, however, they have props, but this isn't necessarily going to save them. When unpowered and falling, the props spin in the opposite direction as they're supposed to, which does sometimes add a bit of lift and stability (this is good), but can also prevent the motors from being restarted (this is bad). And larger props seem to offer greater lift at the expense of passive stability. I love the idea of those passive flaps, but what I really love is that some guy just decided that he'd figure out what happened to quadcopters in free fall, and then went out and actually did it. We salute you, Mr. RcTestFlight guy. Well done.

Also, we should mention that doing this is almost definitely illegal in the United States, since you're not supposed to exceed 400 feet (122 meters) with a quadcopter. So if you try this, be safe and don't get caught. And then send us video.

[ RCTestFlight ] via [ DIY Drones ] and [ Hackaday ]

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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
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

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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