in action at the Artificial Muscle Research Institute (AMRI) at the University of New Mexico, where a skeleton called Myster Bony has been fitted with artificial leg muscles.Perched on a fixed exercise bike, with its muscles hooked up to electrical power, Myster Bony pedals away indefinitely—or at least as long as the electricity holds out.An- other example at AMRI is an artificial fish slowly swimming through the water as its tail, powered by an artificial muscle, switches gently from side to side. AMRI, where researchers study several types of artificial muscles, involves both engineers and medical researchers; some of its projects provide hope for eventually using synthetic muscles to help people with muscular dystrophy.
Further uses of EAP and similar materials can be seen in Bar- Cohen’s laboratory in Pasadena, every corner of which contains a different device that illustrates the versatility of smart materials. For example, NASA is constantly seeking reliable, lightweight materials for use in space, so Bar-Cohen designed a tiny EAP-driven wind- shield wiper that sweeps back and forth to dust off a small glass obser- vation window.As Bar-Cohen puts it, this is a device where “suddenly the material is everything,” meaning it performs without conven- tional moving parts such as gears and bearings, a tremendous advan- tage for space applications. NASA approved the wiper for use aboard a small, wheeled robot called Nanorover.With a mass of 1.1 kilograms (2.5 pounds), Nanorover was designed to explore and send back data from a small asteroid, much as the Sojourner rover explored the sur- face of Mars.
Also in Bar-Cohen’s laboratory is a model of a human head sculpted by David Hanson, who has designed animatronic entertain- ment robots for the Walt Disney Company. Its facial details, texture, and coloring are persuasive, down to the slightly bloodshot eyes: but the most fascinating feature is that its eyes and mouth are moved by artificial muscles of Hanson’s own design.Although these muscles do not employ EAP materials, they show what synthetic muscles can do: With the power turned on, the mouth smiles and the eyes move (one winks), a powerful example of the power of muscles over gears in robot animation.