Waveguided, Self‐Sensing Sheath–Core Liquid Crystal Elastomer Fiber Actuators

Soft actuators capable of operating in confined and hard-to-access environments, while providing integrated self-sensing capabilities, are highly desired for next-generation robotic systems. Here we report a waveguided sheath-core optical fiber actuator consisting of a liquid crystal elastomer core encased in a conductive sheath of carbon nanotubes/carbon black. Near-infrared light guided through the fiber actuator drives reversible contractions of up to 38% and enables a load-bearing capacity of up to 320 times the actuator's own weight. Arrays of these fibers enable independent optical addressing of individual actuators, allowing programmable multimodal gripping in confined environments. The conductive sheath simultaneously serves as a strain sensor, providing real-time monitoring of actuation states via changes in resistance. By integrating photothermal actuation and self-sensing into a single fiber architecture, this work establishes a multifunctional platform for soft robotic systems operating in spatially confined environments.