MIT researchers writing in a recent Physical Review Letters discuss the role of conjugated polymers in making speedier actuators. This breakthrough can help manufacturing and transportation, and perhaps someday, make kung-fu robot fighters possibe:
In the past few years, engineers have made the 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. (Conventional polymers like rubber and plastic are insulators and do not conduct electricity.)
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). A soliton, short for solitary wave, is “like an ocean wave that can travel long distances without breaking up,” Yip adds…
…Scientists already knew that solitons enabled the conducting polymers to conduct electricity. Lin’s work attempts to explain how these materials can activate devices…
Lin discovered that adding the ions is unnecessary, because theoretically, shining a light of a particular frequency on the conducting polymer can activate the soliton. Without the extra weight of the added ions, the polymers could bend and flex much more quickly. And that rapid-fire motion gives rise to the high-speed actuation, that is, the ability to activate a device.
More from MIT’s Professor Sidney Yip…
Via Engadget…
