Predicting the Electrical, Mechanical, and Geometric Contributions to Soft Electroadhesives through Fracture Mechanics

Electroadhesion is the modulation of adhesive forces through electrostatic interactions and has potential applications in a number of next-generation technologies. Recent efforts have focused on using electroadhesion in soft robotics, haptics, and biointerfaces that often involve compliant materials and nonplanar geometries. Current models for electroadhesion provide limited insight on other contributions that are known to influence adhesion performance, such as geometry and material properties. This study presents a fracture mechanics framework for understanding electroadhesion that incorporates geometric and electrostatic contributions for soft electroadhesives. We demonstrate the validity of this model with two material systems that exhibit disparate electroadhesive mechanisms, indicating that this formalism is applicable to a variety of electroadhesives. The results show the importance of material compliance and geometric confinement in enhancing electroadhesive performance and providing structure-property relationships for designing electroadhesive devices.