Science Journal Recognizes the Technical Impact of SRI International’s Artificial Muscle Technology

An article in the January 2011 issue of the journal Science commemorates the anniversary of a smart material technology first described a decade ago in the same publication. In 2000, SRI researchers published a research paper introducing electroactive polymer artificial muscle (EPAM), a unique smart material technology SRI developed.

“The 2000 study in Science was the first to report new EPAM materials and configurations with actuator performance beyond natural muscle in strain and energy output,” said Ron Pelrine, chief scientist at SRI, principal inventor of EPAM technology and lead author on the 2000 EPAM research paper. “Since then, research and commercial labs worldwide have advanced the field in pursuit of EPAM applications. Research papers have been published on topics ranging from the fundamental, such as the physics of EPAM, to new devices such as electronically variable surface textures.”

In 2005, SRI spun off Artificial Muscle Inc. (AMI), to further develop the technology and introduce products based on EPAM. In 2010, AMI became a subsidiary of Bayer MaterialScience LLC.

AMI’s next generation technology brings a new dimension to mobile gaming by allowing users to feel the difference between sensations when holding their mobile gaming device in their hand. While the possibilities are endless, examples include feeling a ball roll through a maze, a rifle fire and reload, dice bump against a table or a sword cut through flying objects.

In January, the Mophie Pulse game enhancing grip for the iPod Touch was announced as the first commercial product integrated with AMI’s next generation technology, ViviTouch actuators. The Mophie Pulse was introduced at CES 2011 in Las Vegas and received two awards for Best in Show.

“We expect the initial success of Mophie Pulse to validate the use of EPAM for haptic related products in the consumer electronics industry,” said Dirk Schapeler, CEO of AMI. “EPAM technology offers many more possibilities that we want to develop and market in the future.”

EPAM is based on a rubbery polymer material that expands and contracts using compliant electrodes. Because of its inherent muscle-like characteristics, EPAM can enable robots to mimic the dexterity and mobility of humans, and offers performance characteristics similar to those of natural muscle such as high strain, high peak power, and high compliance. In addition to acting as a muscle-like actuator, EPAM can also operate in reverse and generate power from being stretched and contracted.

“In the last 10 years, these EPAM characteristics are enabling a wide variety of applications, including haptic displays to improve human computer interaction, adaptive optics, flat conformal loudspeakers, and may potentially be used in implantable active medical prosthetics,” said Roy Kornbluh, principal research engineer at SRI, and co-author of the 2000 EPAM research paper. “The technology has demonstrated promise for a variety of actuator and electric power generation applications.”