Diverse actuation of light-responsive LCE's*

Liquid crystalline elastomers represent a promising area for synthetic microactuators, which can produce complex twisting and bending behavior from a simple, compositionally-uniform structure. Using light-responsive moieties allows us to localize the nematic-isotropic transition that actuates the elastomer. By varying the incident angle and intensity of the light, we can control the thickness and position of this isotropic layer, allowing us to produce a rich variety of deformations from a single microstructure. We make use of a finite element model to capture the interplay of the time-varying light transmission through the material in conjunction with the illumination or shadowing of different areas of three-dimensional molded micro structures as they twist and bend. The predictions of these simulations are then validated experimentally.