Gloves inspired by the method used by geckos to climb walls have enabled a human to scale a 12ft vertical pane of glass.
The 11-stone volunteer used sticky attachments on his hands and feet developed by Stanford University’s Biomimetics and Dexterous Manipulation Lab that exploits the electrostatic Van der Waals forces, used by the ceiling-hugging lizards, which cause neighbouring molecules to be attracted to each other.
The effect of the force is multiplied by thousands of tiny hairs that cover a gecko's toes, allowing them to stick firmly to surfaces. Using the same principle, scientists created tiny tiles called microwedges to generate Van der Waals forces and produce a dry adhesive even more efficient than the gecko's.
The US team led by Dr Elliot Hawkes wrote in the Journal of the Royal Society Interface: "Using this system, a human of mass 70kg (11 stone) successfully ascended a 3.6m vertical glass wall with 140cm2 of gecko-inspired dry adhesives in each hand.
"We tested hundreds of individual steps on glass with the 70kg climber and 140cm2 of adhesive without failure.
"The synthetic adhesion system creates a nearly uniform load distribution across the whole adhesive area, improving upon the adhesive-bearing structures of a gecko's toe and enabling a human to climb vertical glass using an area of adhesive no larger than the area of a human hand."
In the test, the volunteer testing the microwedge attachments simply peeled them on and off the glass.
The research was conducted in collaboration with the US Defence Advanced Research Projects Agency (Darpa), whose 'Z-man' programme is investigating biologically-inspired climbing aids for soldiers.
One application of the technology might be to help astronauts get around in weightless conditions, the authors suggest.
"Recent work has shown that microwedges function in the environment of outer space, so it would be of interest to test this adhesion system in such an environment," they concluded.