Ray Baughman, director of the Nanotech Institute at UT Dallas, is developing various kinds of carbon-nanotube-based "artificial muscles" for prosthetics and robotics. These materials change shape and size in response to electrical or chemical signals; some expand by up to 1 percent and exert 100 times more force than natural human muscle over the same area.
New carbon nanotube artificial muscle material could be a good candidate for shape-changing aircraft wings. Pei has developed polymer actuators that expand by up to 400 percent and work between -40 and 200 °C.
Baughman and his colleagues are focusing on optical applications for the material. Because carbon nanotubes are highly conductive, the flexible sheets could perhaps be used to make electrodes for solar cells and organic light-emitting diodes with controllable transparency and conductivity.
Electrical engineer John Madden at the University of British Columbia, who was not involved in developing the material, says that resilience and low density could make it a good material for building structures in space – its lightness keeping down the cost of sending a payload into orbit.
A metre long ribbon of a carbon nanotube 'aerogel' that could make a robust artificial muscle. This ribbon more than trebles its width when a voltage is applied (Image: Ray Baughman)