Grasping Point Estimation for EA Suction Cup Grippers on Curved Objects
Angelo Catalano, Simone De Carolis, Gennaro Vitucci, Giuseppe Carbone, Mariagrazia Dotoli, Vito Cacucciolo
Abstract
Electroadhesion suction cup (EASC) are fully-electrical grippers (no air flow needed) with very low power consumption that can grasp flat to curved objects from the top. They conform to the shape of the object by zipping from the central contact point to their edges, driven by Electroadhesion forces. Zipping requires deforming elastically the EASC membrane. The object surface curvature at contact point strongly affects zipping ability, and therefore grasp feasibility. We developed a model for grasping point selection that predicts the voltage required for full zipping on a point of given local curvature. Feasible points are the ones where the estimated zipping voltage is lower than the breakdown voltage of the EASC. The model is based on an energy balance between electrostatic work and elastic deformation, explicitly including in-plane stretching on doubly curved surfaces. Experiments on cylinders, spheres, and ellipsoids validate the predicted thresholds and curvature-dependent trends.