Characterization of charge retention effects in HASEL actuators

Abstract

Hydraulically amplified self-healing electrostatic (HASEL) actuators offer mechanical performance suitable for soft robotics and wearable devices. Strain decrease associated with sustained DC voltage application (DCV), however, remains a challenge. Here we discuss the role of charge retention (CR) in the actuation behavior of linearly contracting Peano HASELs under different voltage conditions and material compositions. We then discuss techniques for measuring dielectric absorption of different material combinations used to fabricate HASELs and discuss their relationship to CR. Selection of material combinations significantly impacts CR and is crucial to consider for HASELs and other devices driven by electrostatic forces.