Innovative dielectric elastomer actuator driver based on salamander muscle structures

Abstract Salamander robots represent an innovative class of crawling robots that combine flexible limbs and spines to achieve exceptional motion stability and adaptability in unstructured environments. These biomimetic systems employ soft actuators that replicate the smooth, organic movements of living organisms, significantly enhancing fluid interaction efficiency and propulsion performance. This research specifically focuses on improving dielectric elastomer actuator (DEA)-based fish-like underwater robots by developing a novel drive mechanism inspired by the salamander musculature. While aquatic organisms such as fish possess complex muscle structures that challenge direct imitation, salamanders offer a more tractable model due to their simpler anatomical organization. Notably, the lateral inferior axonal muscles in salamanders exhibit a nearly flat configuration, with myomangial membranes arranged in a linear distribution from the lateral midline to the abdominal midline — a structural feature that is particularly amenable to DEA replication. Through systematic analysis of salamander morphology, this study develops a DEA driver model that investigates two critical performance parameters: (i) the impact of electrode geometry on the bending angle; and (ii) the relationship between driver quantity and angular displacement. The experimental results confirm that DEAs mimicking salamander muscle architecture can achieve substantially increased bending angles under optimized conditions, thereby demonstrating measurable improvements in robotic propulsion capabilities.