Novel Flexible Dielectric and Ionic Electroactive Actuators for Soft robotics

Soft robotic actuators and their applications have gained significant attention in the last few years, especially in the medical field. Compared with other soft actuators, electroactive polymers are of interest in the bioactive field due to their lightweight, fast response, and mechanical properties. This study demonstrates a novel actuation mechanism, using dielectric-polymer film actuators, driven by a non-homogeneous electric field generated by an out-of-plane electrode configuration. A wide variety of dielectrics can be used, including novel materials such as triblock copolymers (PS-PMMA-PtBA) and polymer-grafted films, such as PVDF blended with PE grafted onto BaTiO₃ and PE grafted onto SiO₂ nanoparticles, as well as PVDF blended with Fe₃O₄ nanoparticles. Our dielectrophoretic actuators show unique behavior in which the dielectric films actively bend outward toward the upper electrode. It is designed such that there is no direct contact with the upper electrode and the upper electrode above the film by 0.8 cm, a notably large displacement. Furthermore, PVDF based ionic electroactive polymer (iEAP) actuators incorporating ionic liquids were developed, enabling actuation at significantly lower electric fields, due to enhanced ion mobility. These ionic-liquid-based actuators exhibit high flexibility and biocompatibility, making them suitable for use as artificial fingers for individuals with disabilities.