Speedy muscles

researchers led by Professor Sidney Yip have proposed a new theory that might eliminate the limited speed and control of present day artificial muscles.

Currently, robotic muscles move 100 times slower than ours. But potentially, engineers applying the Yip lab's new theory could boost those speeds -- making robotic muscles 1,000 times faster than human muscles -- with virtually no extra energy demands and the added bonus of a simpler design.

In the past few years, engineers have made artificial muscles that actuate, or drive, robotic devices from conjugated polymers.

"Conjugated polymers are also called conducting polymers because they can carry an electric current, just like a metal wire," says Xi Lin, a postdoctoral associate in Yip's lab, whereas conventional polymers like rubber and plastic are insulators and do not conduct electricity.

And these conjugated polymers can actuate on command if charges can be sent to specific locations in the polymer chain in the form of "solitons" (charge density waves). Solitons are highly mobile charge carriers that exist because of the special nature (the one-dimensional chain character) of the polymer.