Actuation simplification for grippers based on bioinspired spring origami

Abstract

Soft robotics promise to enable large reconfigurability in robotic systems, in turn allowing interaction with unknown objects in unstructured environments. Most applications in soft robotics draw from natural examples for inspiration in sensing, actuation and control functions needed to achieve desired operations. In this respect, many organisms realize complex tasks with minimal efforts exploiting material system architectures that store mechanical energy that can be used for reconfiguration. Examples include the fast motion exhibited by the Venus Flytrap and the remarkable multifunctionality of the Earwig wing, both of which exploit prestress and multistability. We present a bioinspired spring origami gripper that is capable of conforming and holding objects several times its weight with minimal sensing and actuation systems drawing from the characteristics of the Earwig wing. This is achieved by exploiting the multiple functions afforded by the multistability that allows functional geometries for gripping and holding onto objects. We extend a previously developed model to design the bistable gripper and validate the obtained results with experimental tests.