Dynamic Strain Delay of Dielectric Elastomer Sensors: Influence and Elimination

Abstract

Dielectric elastomer sensors (DESs) have demonstrated great potential applications in the fields of human motion capture, rehabilitation training, health monitoring, and soft robotic sensing. However, precise dynamic sensing by DES has not yet been achieved because of the lack of analysis of their dynamic characteristics. This letter analyzes the dynamic characteristics of DESs and finds a remarkable strain delay in dynamic stretching and recovery, which is correlated to historical stretching, deformation speed, and maximum strain. A Burgers four-element model was used to quantitatively analyze the strain delay, and the results are validated by experiment. Strain delay can reduce DES precision, and therefore, a method based on prestretching was proposed to eliminate its influence. Precision of the DES can be remarkably improved after elimination of the strain delay.