Modeling and control of electroadhesion force in DC voltage

In this paper, a new model for electroadhesion between two surface-insulated plates under DC electric field is presented and control of dynamic responses of electroadhesion force is discussed. Under DC electric field, even if the voltage difference between the plates is constant, electroadhesion force increases or decreases over time depending on the insulating materials. The increase had been explained by Johnsen–Rahbek (JR) model, but the decrease had not been focused or modeled by physically meaningful way. In addition, the previous models did not explicitly consider the mechanical behaviors of the electrodes, although the mechanical behaviors considerably affect the response. In this work, we introduced a new model that combines both electrical and mechanical behaviors. The electrical part, which is based on JR model, explained the force decrease under DC field, in addition to the force increase that had been explained using JR model. The mechanical part was represented by a combination of a spring and a damper. Numerical simulations using the model successfully reproduced characteristics behaviors of electroadhesion force, which include force decay under constant voltages and relatively smaller initial force. Using the inverse model, we carried out experiments to control dynamic responses of electroadhesion force, which successfully controlled force responses against pulse voltages. Through the experiments, we also showed the importance of the neutralization of surface charges for obtaining reproducible responses.