Evolving Dielectric Elastomer Artificial Muscles

Abstract

Electroactive polymer artificial muscles are an emerging class of transducers with properties not found in exiting actuators, generators, or sensors. A particularly promising class of electroactive polymers is dielectric elastomers. Dielectric elastomers are based on the electrochemical response of a rubbery material located between compliant electrodes. Properties of dielectric elastomers that are relevant for medical applications include softness similar to biological tissues, actuation stroke and force similar to biological muscles, use of biocompatible materials, high energy efficiency, the ability to form arrays on a single substrate, and extremely low material costs. These properties may be exploited for a variety of medical applications both in devices for the human body such as prosthetics, assistives, or diagnostics as well as in devices for diagnosis and medical research in laboratories or clinics. Specific examples of dielectric elastomer devices under development include artificial muscles for prosthetic limbs, soft skins for haptic stimulation and sensing, disposable microfluidic devices with embedded pumps and valves, and prosthetic and orthotic organ devices such as artificial diaphragm and heat assist devices. Some lifetime and packaging issues remain, but we expect to see devices based on electroactive polymer artificial muscles with new capabilities in medicine within the next few years.