Electroactive Polymer Actuators

Abstract Electroactive polymers (EAPs) have emerged as feasible materials to emulate biological muscles due to their ability to undergo significant changes in shape or size in response to electrical stimulation. They have received immense consideration in various fields of applications such as robotics, biomimetics, wearable electronics, prosthetics, optical devices, and so on owing to their mechanical flexibility, easy processing, light weight, low density, fracture tolerance, pliability, and the ability to induce large actuation strains than other conventional mechanically responsive polymers. Electronic EAPs including dielectric elastomers, ferroelectric polymers, liquid crystal elastomers, and electrostrictive graft polymers are driven by electric fields or Coulomb forces and require high voltage for activation. While ionic EAPs such as ionic polymer metal composites, ionic gels, conducting polymers, carbon nanotubes, and electrorheological fluids are driven by the drifting or diffusion of ions and operate at lower voltages. The emphasis in this article is on the studies of key materials used in the field of electroactive polymer actuators, reviewing the mechanism that drives the actuation, highlighting their advantages and disadvantages, and discussing their applications.