Carbon Nanotube Muscles Strong as Diamond, Flexible as Rubber

Baughman and his colleagues have produced a formulation that's stronger than steel, as light as air and more flexible than rubber — a truly 21st century muscle. It could be used to make artificial limbs, "smart" skins, shape-changing structures, ultra-strong robots and — in the immediate future — highly-efficient solar cells.

"We can generate about 30 times the force per unit area of natural muscle," said Baughman, director of the NanoTech Institute at the University of Texas at Dallas.

His latest muscle, described Thursday in Science, is made from bundles of vertically aligned nanotubes that respond directly to electricity. Lengthwise, the muscle can expand and contract with tremendous speed; from side-to-side, it's super-stiff.

The first applications, said Baughman, will likely be as wrappers for solar cells