Gecko-Effect Inspired Soft Gripper with High and Switchable Adhesion for Rough Surfaces

Geckos, which can walk upside down on smooth or rough surfaces, owe this ability to the hierarchical structures under their toes. These structures are responsible for substantial adhesion and, at the same time, for quick attachment/detachment by mechanical stimulus of toe muscles. Inspired by such stimuli-responsive systems in nature, an active adhesive soft gripper for rough surfaces is proposed in this study, consisting of the mushroom-like morphology acting as adhesive structures and the pressure controllable deformation working as toe muscles. Through tunable pressure, the adhesive force can be increased and reduced by roughly 20-fold for a ground glass, in which it can quickly reach high adhesion with positive pressure and reduce to small adhesion under negative pressure. This gecko inspired soft gripper is tested and found successful as a pick-up and drop-down system for transporting a surface with different features, composed of rough acrylic plate, steel ball, flexible photo paper, heavy glass block/plate, etc., which will have great potential for applications in industrial line and daily life as well as providing a novel perspective for the design of soft grippers.