Scaling buildings like Spiderman could be a reality, scientists claim
Published 26/08/2010 | 11:56
Walking up the side of buildings like Spiderman could soon be a reality, scientists have claimed.
Sticky gloves and shoes are being developed using a material that allows the person wearing to stick to and climb up walls.
They have already created a new textile inspired by geckos which has been tested successfully on a small robot that can scale smooth surfaces such as glass and metal.
Engineers now want to "scale up" the design for humans as part of a project that has been codenamed Z-Man.
Geckos' ability to defy gravity is due to microscopic hairs on their toes, increasing the surface area, which creates a "one-way adhesive". A sticky bond is created with each step but that bond can be broken by movement in the other direction.
Technicians have struggled over the last 10 years to create an artificial version strong enough for a vertical climb to be attempted successfully. However, researchers at Stanford University, California, have created a rubber-like material covered with thousands of tiny polymer fibres to imitate the gecko's hairs. These hairs, which are called setae, are ten times thinner than a human hair.
The material is said to be strong and reusable, and leaves no residue or damage. It has been tested on a "robotic gecko" called Stickybot which can walk up panes of glass.
Scientists are now on the way to making a version of the material that "would allow humans to climb with gecko adhesive."
This would allow someone to hang and support their whole weight using the material.
Professor Mark Cutkosky, the lead designer, said, "Unless you use suction cups, which are kind of slow and inefficient, the other solution out there is to use dry adhesion, which is the technique the gecko uses."
The secret lies in the gecko's "one-way adhesive" which makes them very sticky when they touch a surface in one direction - but then come free when pulled back in another.
"It's very different from Scotch tape or duct tape, where, if you press it on, you then have to peel it off," explained Professor Cutkosky, an expert in "bio-inspired robotics".
He added: "Other adhesives are like walking around with chewing gum on your feet: You have to press it into the surface and then you have to work to pull it off. But with directional adhesion, it's almost like you can sort of hook and unhook yourself from the surface."
The Stickybot is shaped like a gecko with four feet, each about the size of a child's hand. As it steadily moves up the wall, the robot peels and then sticks its feet to the surface with ease, just like a real gecko.
Stanford University said efforts to make the material strong enough for humans was "in the works."
The development of the robots, which use adhesive toes and an agile tail to scale walls, just like a gecko, is funded by the US Department of Defense's advanced research projects programme.