HASEL Actuator Design for Out-of-Plane Bending: A Parametric Study of Planar Geometry

Soft robotic systems are promising for a wide range of applications from locomotion to manipulation. In particular, fluidic dielectric elastomer actuators, such as Hydraulically Amplified Self-healing ELectrostatic (HASEL) actuators, demonstrate several compelling properties when compared to other soft robotic actuators such as lower power consumption, faster response times, and self-sensing capabilities. Current HASEL actuator research has thoroughly characterized linear HASEL actuators, but there is a lack of geometric characterization for bending HASEL actuators. This paper addresses this gap through the characterization of two important design parameters that affect out-of-plane bending of planar HASEL actuator designs. In particular, a sinusoidal wave pattern is parameterized by the period length and the minimum channel width. The ratio of the period length to channel width is shown to be a good predictor for the curvature of the HASEL actuators when bending out-of-plane. The experimentally derived relationship is then used to demonstrate different grasp types for various objects.