It's not Spiderman, it's "gecko man," with researchers at Stanford University demonstrating a gecko-inspired climbing technology that allowed a graduate student to climb up a glass wall when fitted with two hand-sized sticky pads.
Scientists have spent ten years trying to solve the secret that allows geckos to climb walls and even walk upside down across a ceiling.
The lizard's trick is made possible by rows of tiny hairs on the bottom of their feet that can amplify the weak electrical attractions between their feet and the surface they're walking on.
Gecko feet adhere well but release their grip readily when the creature shifts its weight, and can stick repeatedly, something most man-made adhesive tapes can't duplicate.
While scientist shave managed to create various artificial adhesive formulations that work in a similar way, made from carbon nanotubes clusters or microscopic arrangements of molded rubber, they've only worked well for small weights.
The trick, the Stanford researchers said, was creating enough adhesion in a gripper suitable for human use. With some previous materials, a 150-pound human would need gecko-foot-like pads 10 times the size of a normal human hand in order to scale a vertical wall.
"Scaling gecko adhesion is a challenge," says Stanford engineer and study leader Mark Cutkosky.
In the Stanford climbing technology, the lizard's hairs are replaced with molded microwedges of a polymer material attached to a flat, hexagonal, hand-sized gripper.
Each gripper was also fitted with a spring that distributes the climber's weight across the pad's surface and absorbed some of the force involved in climbing.
The climbing grad student wasn't as agile as a gecko, the researchers acknowledged, but that wasn't a problem with the climbing system.
"The climbing speed was limited by the posture of the climber, not by the adhesion system (which can attach and detach in less than a second), so further work optimizing the climbing device for human biomechanics is warranted," the researchers wrote in a report of their studies in the Journal of Royal Society Interface.
The researchers say they've been working with NASA's Jet Propulsion Laboratory to create a gecko-like adhesive that could be fitted to robots to allow them to capture space junk such as decommissioned satellites.
Their gripping technology could be used for "manufacturing equipment, making grippers for manipulating huge solar panels, displays, and other objects without the need for suction power or chemical glues," the researchers said.
