Electromechanical actuation of dielectric liquid crystal elastomers for soft robotics*

Liquid crystal elastomers, networks of anisotropic molecules, are two-way reversible shape memory polymers. They have long been considered as intelligent materials reminiscent of biological muscles with orientational order. Despite significant developments in chemistry, processing, and handling methods of liquid crystal elastomers, most demonstrated actuation mechanisms still rely on thermal or optical stimulation, which often suffers low efficiency of energy conversion into useful work. Here, we report fast and efficient electrical stimulation of liquid crystal elastomer actuators with high output work density for potential soft robotics applications. Different from conventional dielectric elastomers, which often require prestrain, the intrinsic elastic anisotropy in liquid crystal elastomers allows us to design complex patterns of locally aligned liquid crystal molecules. In turn, we demonstrate pre-programmed twisting, bending, and other actuations.