Could spider-man suits become a reality?
Whilst having the ability to climb up the sides of skyscrapers might not be top of everyone’s wish list, being able to replicate the way that geckos stick to surfaces would be extremely valuable.
As gecko feet don’t use any fluids, it would be just as easy for a gecko to stick to the outside of the International Space Station as it would to stick on your ceiling – assuming of course that it had a gecko-sized spacesuit. Also, gecko feet don’t lose their stickiness, so any adhesive material using the same sticking process could be used again and again.
Mimicking gecko feet
Physicists worked out that the secret to geckos’ sticky feet lay in the tiny hairs and spatulae on their soles by looking at them using powerful electron microscopes. Once they knew the secret, physicists started trying to mimic gecko feet using artificial materials. But this is easier said than done. Firstly you need to be able to produce something that can mimic the tiny hairs and spatulae structures to recreate the van de Waals forces, then you need to make sure that it won’t lose its stickiness from bits of dirt and dust getting trapped in between the tiny hairs. Finally you need to make sure that you can unstick it!
Recently, researchers at the Polytechnic of Turin, Italy, claimed to have cracked it – in theory anyway. Taking velcro as an added inspiration, they suggest using microscopic loops and hooks, and ultra strong carbon nanotubes as a way of mimicking the geckos’ hairy feet. This has the added advantage of allowing the material to be unstuck easily. To keep the material at maximum stickiness it needs to be self-cleaning, so the researchers suggest that by manipulating the shape and structure of the carbon nanotubes they could make the material hydrophobic. In other words it would repel water and with it remove any trapped dust and dirt.
There are still a few problems to overcome before anyone will be scaling buildings wearing a gecko suit. For example, what area of the sticky suit would need to be in contact with the surface to keep a real life Peter Parker stuck to a building? And would he experience some serious muscle fatigue if he hung around too long?
Find related websites about the gecko suit with physics.org