Magnetic Augmented Self-sensing Flexible Electroadhesive Grippers

Abstract

Current electroadhesion (EA) grippers cannot be used to lift objects with limited contact areas. Current electromagnetic adhesion (MA) grippers cannot be used to grip nonferrous materials. Here, we combine EA and MA into a monolithic, electrically controllable, flexible, and hybrid electro/magneto-adhesive (E/MA), to offer EA grippers augmented with magnetoadhesion and MA grippers augmented with electroadhesion. This E/MA was achieved by exploiting two intertwined coplanar coils inspired by Tesla's flat bifilar coil. By appropriate electrical connections an electromagnetic field is generated - driving magnetic attraction- or an electric field is generated-delivering electroadhesion-or both fields can be generated simultaneously. As a result, the E/MA grippers cannot only be used to lift ferrous and nonferrous materials, but also low-density objects, such as office paper clips. We also present a customized capacitance measurement method to enable an autonomous material handling system without embedding external sensors. E/MA grippers have the potential to expand the capabilities and impact of soft robotics and industrial gripper systems.