Electrostatic artificial muscles for cable-driven actuation of compliant mechanisms

Abstract

Dielectric elastomer actuators (DEAs) are soft, electrically-driven artificial muscles with high energy density and high bandwidth. As work requirements increase, the actuator volume must also increase. Integrating sufficiently large DEAs within mechanical linkages for robotic applications can be challenging since the actuators can be of comparable size to the mechanism itself (as with human forearm muscles and hands). Here, we demonstrate a way to use DEAs to power cable-driven mechanisms, thus allowing the actuator to be separated from the mechanism, enabling modularity in design. We detail the manufacture and characterization of scaled-up rolled DEAs for increased work output via a sequential roll-on-roll method, and cable integration for remote actuation. This cable-DEA architecture is used to actuate a pinching gripper, a multi-degree-of-freedom mechanism, and a soft end-effector. This work illustrates a promising method to pair the unique actuation characteristics of DEAs to rigid-material mechanisms.