from Eric Bland, Discovery News
Scientists from Texas and around the world have created a material that, by density, is lighter than air yet, when electrified, instantly and powerfully contracts. Their work is detailed in this week’s issue of the journal Science.
“These artificial muscles are very lightweight and can do wonderful things,” said Ray Baughman, the study author from the University of Texas at Dallas.
While the artificial muscle is unlikely to be used in humans or prosthetic limbs, Baughman says “these sheets of carbon nanotubes … are of great practical interest for LEDs, solar cells, and other applications.”
Aerogels and artificial muscles have been around for decades, but both materials have largely kept to themselves until now. Astronomers have launched spacecraft containing aerogels (so called because 99.8 percent of of the material is air) to gently capture space dust and keep it safe for the return journey to Earth.
Meanwhile, material scientists have created a variety of different artificial muscles, or materials that expand and contract when an electrical charge is applied. Many artificial muscles can only operate within a limited range of temperatures, however, because they contain liquid that will either freeze or evaporate at extreme temperatures.