Think Spider-Man is the only one who can scale the sides of a building with no ropes, hooks or ladders? Think again.
Soon, U.S. troops will be climbing skyscrapers with none of those bulky equipment involved. And, no, it's not because the military has discovered how to create superhuman soldiers. It's because the government has found a way to create gecko-inspired paddles for climbing.
The Defense Advanced Research Projects Agency (DARPA), which is tasked in coming up with new technologies that will improve soldiers' ability to easily and safely navigate volatile urban spaces, has developed a set of sticky handheld paddles that can help soldiers climb walls through its Z-Man project. A demonstration of the new technology showed a 218-pound soldier with a 50-pound pack climbing a glass wall 25 feet high and climbing back down.
Mobility gives soldiers in combat the upper hand, says DARPA officials. Gaining access to higher ground gives them an advantage when fighting in tight urban areas. However, the military has struggled to balance this need with the limitations imposed by carrying additional baggage in the form of ropes and ladders. Moreover, soldiers cannot exactly conceal themselves in covert operations when forced to climb with ladders. DARPA also says when troops have to climb with ropes, they climb in single file, which puts the person in the lead in danger.
These challenges have compelled DARPA to come up with a solution, one that comes in the form of paddles inspired by nature.
"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 areas," says Dr. Matt Goodman, program manager of Z-Man, in a press release. "The challenge to our performer team was to understand the biology and physics in play when geckos climb and then reverse-engineer those dynamics with an artificial system for use by humans.
The Z-Man paddles mimic the structure of the gecko's feet, which are covered in hundreds of microscopic hair-like structures called setae. Each of these setae have ends that are covered with up to a thousand even tinier triangular bristles called spatulae. The size and shape of the spatulae is what allows the gecko's feet to stick to a vertical surface through a special kind of molecular attraction called van der Waals force.
However, van der Waals is a weak attraction, which allows the gecko to unstick from a surface as easily as it sticks to it. Herein lies one of the main challenges for the creators of the Z-Man paddles, which are made not for transporting 6.4-ounce geckos but 165-pound soldiers most likely carrying additional pounds of baggage with them. The spatulae on a gecko's footpad essentially allows it to hang its entire body by a single toe, but DARPA researchers had to find the right balance of adhesive forces so that soldiers don't fall off while unsticking the paddles from the climbing surface.
DARPA is still in the process of testing its latest technology and the paddles that can give soldiers Spider-Man-like climbing abilities are not ready for battle yet.