Artificial muscles using electroactive polymers (EAP): capabilities, challenges and potential

For decades, EAP received relatively little attention due to their limited actuation capability. However, in the last fifteen years a series of Electroactive Polymers (EAP) materials have emerged that produce a significant shape or size change in response to electrical stimulation. These materials have the closest functional similarity to biological muscles enabling to engineer novel capabilities that were impossible to do up until recently. Efforts are underway to address the many challenges that are hampering the practical application of these materials and recent progress already led to dramatic capability improvements. Various novel mechanisms and devices were demonstrated including robot fish, catheter steering element, robotic arms, miniature gripper, loudspeaker, active diaphragm, Braille display, and dust-wiper. For developers of future medical devices these materials are offering numerous advantages for their flexibility, fracture toughness, and controllability, as well as low mass and low power requirements. This paper provides a review of the current status, the challenges and potential near future applications of these materials.