Monday, November 24, 2014
Climbing up the walls like a gecko
"The Tokay gecko scurries across ceilings with the help of tiny hair on its feet, which generate weak intermolecular forces that add up to a secure foothold. Scientists have recreated dry gecko-like adhesion using silicones, plastics, carbon nanotubes, and other materials, but they've run into a scaling problem: The stickiness drops rapidly with increasing surface area. Hawkes et al. offer a solution: an adhesive consisting of 24 tiles that distribute loads evenly among themselves, offering the same adhesive strength for sizes from a square millimeter to the area of a human hand. The adhesive works even if one tile fails to stick. Wearing hand-sized adhesives, a 70-kilogram human can climb a vertical glass wall, the team showed." Editor comments @ Science, original article @ J. R. Soc. Interface.