Theoretical model and design of electroadhesive pad with interdigitated electrodes

Electric fields alter adhesive forces between materials. Electroadhesive forces have been utilized in diverse applications ranging from climbing robots, electrostatic levitation to electro-sticky boards. However, the design of electroadhesive devices still largely relies on empirical or "trial-and-error" approaches. In this work, a theoretical model is presented to analyze the electrostatic field between the supporting wall and the electroadhesive device with periodic coplanar electrodes. The air-gap between the surface of electroadhesive device and the dielectric wall is explicitly taken into account in the model to consider its significant impact on electroadhesive forces. On the basis of this model, the electroadhesive force is calculated by using the Maxwell stress tensor. The effects of key design parameters and working environments on the electroadhesion behavior are further investigated. This study not only provides a tool to reveal the underlying mechanisms of electroadhesion but also suggests potential strategies to optimize novel electroadhesive devices for engineering applications.