Robots with gecko feet
One-way adhesive is important for climbing because it requires little effort to attach and detach a robot's foot.
"Other adhesives are sort of like walking around with chewing gum on your feet: You have to press it into the surface and then you have to work to pull it off. But with directional adhesion, it's almost like you can sort of hook and unhook yourself from the surface," Cutkosky said.
After the breakthrough insight that direction matters, Cutkosky and his team began asking how to build artificial materials for robots that create the same effect. They came up with a rubber-like material with tiny polymer hairs made from a micro-scale mold.
The designers attach a layer of adhesive cut to the shape of Stickybot's four feet, which are about the size of a child's hand. As it steadily moves up the wall, the robot peels and sticks its feet to the surface with ease, resembling a mechanical lizard.
The newest versions of the adhesive, developed in 2009, have a two-layer system, similar to the gecko's lamellae and setae. The "hairs" are even smaller than the ones on the first version about 20 micrometers wide, which is five times thinner than a human hair. These versions support higher loads and allow Stickybot to climb surfaces such as wood paneling, painted metal and glass.
The material is strong and reusable, and leaves behind no residue or damage. Robots that scale vertical walls could be useful for accessing dangerous or hard to reach places.
The team's new project involves scaling up the material for humans. A technology called Z-Man, which would allow humans to climb with gecko adhesive, is in the works.
Cutkosky and his team are also working on a Stickybot successor: one that turns in the middle of a climb. Because the adhesive only sticks in one direc
|Contact: Dan Stober|