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UAVs Flex Their Artificial Muscles

Foldable, bendable actuators could lead to foldable, bendable UAVs that you can stuff into your pocket

2 min read
UAVs Flex Their Artificial Muscles
Image: EPFL LIS

Until recently, a defining characteristic of robots has been their rigid mechanical nature. Most of them are made up of hard structural elements, motors and actuators, electronics, sensors, and batteries, none of which are compliant. The future, though, promises to be softer, and we’ve seen lots of different robots that are either partially or completely soft. Soft robots have the potential to be much more adaptable, portable, and durable than rigid robots do, so ideally you’d want them for field applications where there might be a lot of crashing involved. Like UAVs. That would be a good idea, wouldn’t it?

Landing is hard for UAVs. It’s hard for the winged variety especially, since they can’t zero out their horizontal velocity before they hit the ground. Small UAVs can be made out of foam, with mostly integrated components, but they’ve still got fragile external bits that are vulnerable to damage. Namely, the elevons that the wings use for pitch and roll control. The Laboratory of Intelligent Systems at EPFL has developed a UAV that uses dielectric elastomer actuators (DEAs) as elevons: it can fly perfectly well, but the actuators are so compliant that you can literally bend them in half:

Here’s what the researchers have to say about the approach:

We have flown the MAV numerous times and found the DEA actuators allow for excellent controllability of the aircraft, as well as being very resistant to harsh handling.

In case you missed the brief “let’s bend this actuator completely in half” clip in the video, here’s a picture of the entire actuator being bent completely in half:

One advantage of this actuator is the near imperviousness it confers to the aircraft thanks to its inherent softness and stretchability. Or at least, to the elevons. What’s potentially more exciting (I think) is the potential to make an aircraft that can be folded up and stuffed into a bag, or even into a pocket, and then pulled out and tossed into the air whenever you need it.

DEAs aren’t a new thing, even if this particular implementation is a novel one. EPFL has also adapted them for other robotic applications, like this adorable little gripper:

“A Foldable Antagonistic Actuator,” by Jun Shintake, Samuel Rosset, Bryan Schubert, Dario Floreano, and Herbert Shea from EPFL, will be published in a forthcoming issue of IEEE Transactions on Mechatronics.

[ EPFL ]

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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
DarkGray

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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