Researchers at the Korea Advanced Institute of Science and Technology (KAIST) and Pusan National University in South Korea recently developed a graphene-enhanced actuator for robotics applications, that is inspired by mammalian skeletal and muscle structures. The new actuator is based on soft fibers with strong contractive actuation properties.
The team explained that they based their work on liquid crystal elastomer (LCE) actuators, promising soft actuator materials with unusually large reversible dimensional change (shrink/relaxation) upon actuation, which is rarely observed in other kinds of actuator materials but highly significant to ideally mimic natural skeletal muscle behavior. Many actuators developed in the past are based on LCE materials, a class of polymers that can rapidly change shape in response to environmental stimuli. Despite their shape-morphing advantages, LCE polymers are known to be associated with the relatively poor mechanical properties and weak actuation behavior. To overcome this limitation, the researchers incorporated graphene fillers within the LCE actuators. In addition to enhancing their mechanical properties, the team expected the graphene fillers to enable light-driven, rapid and remotely controllable actuation, owing to the photothermal conversion capability of graphene.