Polyacrylate-Based Dielectric Elastomer Fiber Actuators for High-Performance Artificial Muscles

Dielectric elastomer fiber actuators (DEFAs) are promising candidates for artificial muscle applications, owing to their high axial actuation and mechanical compliance, yet achieving scalable fabrication without compromising electromechanical performance remains a critical bottleneck. Existing continuous manufacturing routes are predominantly restricted to silicone elastomers, which yield limited actuation strains and low energy densities. Here, a continuous fabrication strategy that integrates coaxial wet spinning with in situ ultraviolet curing is developed to produce polyacrylate-based DEFAs (PA-DEFAs) from a bimodal-networked polyacrylate dielectric elastomer at rates up to 22.5 mm s^-1. The fiber geometry and electromechanical properties are readily tunable by adjusting the core-to-shell flow-rate ratio and elastomer formulation. The resulting fiber actuators deliver a maximum prestretch-free axial strain of ∼39%, a maximum energy density of 54.8 J kg^{- 1}, and a peak power density of 443 W kg^{- 1}-outperforming previously reported continuously fabricated DEFAs. The long and continuous fiber architecture further enables wrapped actuator and parallel-connected arrays, facilitating seamless integration into diverse soft robotic systems, including a robotic arm, a crawling robot, and an underwater robotic manta-ray with modular fault-tolerance. By reconciling scalable manufacturing with high actuation performance, PA-DEFAs establish a versatile and manufacturing-compatible platform for next-generation artificial muscles and adaptive soft robotics.