'Super-adhesive' modeled after geckos

The development of the material is being led by Dr. Jeffrey Sargent and Dr. Sajad Haq, and builds off of the discovery made by scientists of the University of California in 2000. The UC science team unlocked the mystery of the lizard's gravity-defying ability, and went on to synthesize a material that imitated the tiny hairs, called setae, found on geckos' feet. These setae are what give the lizards the ability to climb virtually any surface.

The gecko's foot has microscopic hairs with mushroom-shaped caps on the end that are less than 0.001mm across. The cumulative attractive force, called van der Waals force, allows geckos to run up walls and across ceilings, and even on polished surfaces.

BAE's "Synthetic Gecko" substance's potential as a reusable super-strong adhesive material was developed in BAE's micro-engineering room facilities using a modified version of a technique called photo-lithography, which uses light to etch 3D patterns into a material.

It is made of layers covered with thousands of stalks with splayed tips made of a polyimide. Sargent and Haq believe the material will be produced on a large scale, and can be in practical use within a year.

Synthetic Gecko is advantageous in the respect that it can be used repeatedly, leaves no residue and is not sticky to the touch. The material will only stick when the angle of the microscopic hairs is at the correct angle to the surface beneath, and when pressure is applied to the surface.

It could be useful in a number of areas, including aerospace, medical and commercial. A one-meter- squared patch could hold the weight of a family- sized car, according to Haq. Synthetic Gecko could be used for rapid patch repairs on military vehicles, and even eliminate the need for rivets or fasteners.

Robot crawlers used in aviation to check for flaws or defects currently employ suction to attach themselves to the wings or fuselage, but Synthetic Gecko would eliminate the need for this.

Though there is more testing to be done, the BAE Systems team has demonstrated that the adhesive material does work on rough, dirty and wet surfaces and in controlled conditions. It will most likely be seen in some form of commercial appearance before reaching aerospace applications, due to the stringent testing procedures in the aerospace industry, according to Haq.