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The US military is developing special gloves that would let soldiers scale vertical walls.

Based on a gecko's feet, the gloves are coated with a specialized cloth called 'Geckskin'.

Impregnated with a reversible adhesive elastomer, they cling to surfaces the same way that the gecko's feet do.

Dubbed the Z-Man project, the new, specialized climbing paddles were developed for Darpa by Cambridge Massachusetts' Draper Laboratory. Recently, DARPA demonstrated the latest iteration by having a 218-pound researcher with 50 pounds of recording gear scale a 25-foot tall glass wall.

Dubbed the Z-Man project, the new, specialized climbing paddles were developed for Darpa by Cambridge Massachusetts' Draper Laboratory.

'The gecko is one of the champion climbers in the Animal Kingdom, so it was natural for Darpa to look to it for inspiration in overcoming some of the maneuver challenges that U.S. forces face in urban environments,' said Dr. Matt Goodman, the Darpa program manager for Z-Man.

'Like many of the capabilities that the Department of Defense pursues, we saw with vertical climbing that nature had long since evolved the means to efficiently achieve it.

'The challenge to our performer team was to understand the biology and physics in play when geckos climb and then reverse-engineer those dynamics into an artificial system for use by humans.'

Recently, Darpa demonstrated the latest iteration of its Geckskin by having a 218-pound researcher (saddled with 50 pounds of recording gear) scale a 25-foot tall glass wall.

'The Z-Man programs aims to develop biologically inspired climbing aids to enable warfighters to scale vertical walls constructed from typical building materials, while carrying a full combat load, and without the use of ropes or ladders.

Geckos can climb on a wide variety of surfaces, including smooth surfaces like glass, with adhesive pressures of 15-30 pounds per square inch for each limb, meaning that a gecko can hang its entire body by one toe thanks to a microscopic hierarchical structure composed of stalk-like setae (100 microns in length, 2 microns in radius). Now researchers hope to create a paddle to allow human s to climb

a 16-square-inch sheet of Geckskin adhering to a vertical glass wall while supporting a static load of 660 pounds.

A gecko is able to climb on glass by using physical bond interactions—specifically van der Waals intermolecular forces—between the spatulae and a surface to adhere reversibly, resulting in easy attachment and removal of the gecko's toes from the surface.

The van der Waals mechanism implied that it is the size and shape of the spatulae tips that affect adhesive performance, not specific surface chemistry.

This suggested that there were design principles and physical models derived from nature that might enable scientists to fabricate an adhesive inspired by gecko toes.

'Geckskin' is one output of the Z-Man program. 

It is a synthetically-fabricated reversible adhesive inspired by the gecko's ability to climb surfaces of various materials and roughness, including smooth surfaces like glass. 

Performers on Z-Man designed adhesive pads to mimic the gecko foot over multiple length scales, from the macroscopic foot tendons to the microscopic setae and spatulae, to maximize reversible van der Waals interactions with the surface.

Darpa says the project could give it the upper hand in battle.

'Historically, gaining the high ground has always been an operational advantage for warfighters, but the climbing instruments on which they're frequently forced to rely—tools such as ropes and ladders—have not advanced significantly for millennia.

'Darpa created the Z-Man program to overcome these limitations and deliver maximum safety and flexibility for maneuver and rapid response to warfighters operating in tight urban environments.

'The goal of the program is to develop biologically inspired climbing aids to enable warfighters carrying a full combat load to scale vertical walls constructed from typical building materials.'