From grasping to manipulation with gecko-inspired adhesives on a multifinger gripper.

Abstract

Anthropomorphic robotic manipulators have high grasp mobility and task flexibility but struggle to match the practical strength of parallel jaw grippers. Gecko-inspired adhesives are a promising technology to span that gap in performance, but three key principles must be maintained for their efficient usage: high contact area, shear load sharing, and evenly distributed normal stress. This work presents an anthropomorphic end effector that combines those adhesive principles with the mobility and stiffness of a multiphalange, multifinger design. Adhesive suspensions use buckling ribs to deliver shear load sharing and normal compliance in a deployable form factor. We use an elastic foundation model and fundamentals of grasping theory to motivate kinematic changes when shifting from Coulomb friction to adhesive manipulation. These design considerations integrate with the necessary control infrastructure in a prototype called farmHand, on which we perform tests to confirm shear load sharing and demonstrate adhesive use in manipulation beyond pick and place grasping.