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Gecko Adhesives Moving from Robot Feet to Your Walls

Artificial gecko toes are a beautiful example of bioinspiration in robotics, and they're getting close to a practical application

2 min read
Gecko Adhesives Moving from Robot Feet to Your Walls
Photo: Stanford University

Few robots are as elegantly designed as Stickybot, Stanford's original robotic gecko. The bio-inspiration extends all the way down to the toes, which featured an early generation of gecko toe adhesive. Geckos stick to things using van der Waals' forces generated between the tiny fibers on their toes and whatever surface they're on: it's not sticky in the same sense that glue or tape is sticky; it's a molecular attraction that works on the smoothest of surfaces and can be used over and over. It sounds like something that might be useful apart from robots, and it looks like artificial gecko toes are about to go mainstream, with super strong, reusable Geckskin.

While roboticists have been able to replicate functional gecko toes for a while now, there's a lot more that the geckos themselves have going for them besides just their toe material. Because of the molecular bonding, the material sticks to everything, which means that the geckos spend a lot of time trying to keep their toes clean. Also, while the nanoscopic hairs will stick to anything that they come in contact with, it requires very close alignment with a surface. Geckos make this happen with soft and highly flexible toes, but we haven't been able to reproduce that very well. The picture below shows a robotic gecko (the third generation of Stickybot) sticking to glass, and if you look closely, you'll see that not all of the foot is adhering:

Photo: Stanford University

Geckskin, which is being developed at the University of Massachusetts Amherst, has solved many of these problems by moving away from direct biomimicry of the gecko toe material and using a "draping adhesion" based on wider fibers instead of the smaller hairs that geckos have. Geckskin is able to stick to anything that's vaguely smooth, including glass, metal, drywall, and wood, and it even works on surfaces that are slightly curved.

The big advantage of Geckskin (besides the loads that it can bear) is that it's very easy to remove from surfaces. Like gecko toes, Geckskin has to be loaded in one specific direction to stick: while there's weight on it pulling down, it'll adhere, but removing the weight and pulling up will peel it right off. To work best, it looks like you have to force the Geckskin very tightly against the surface with a tool, but that doesn't diminish its convenience or usefulness by much.

Watch the video below for seven minutes worth of clips demonstrating that Geckskin really can stick to different surfaces over and over and over; the UMass team has just published a paper on Geckskin, and we're hoping that some kind of commercial development is coming next. And maybe this.

Via [ UMass Amherst ]

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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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