High-Load Soft Grippers Based on Bionic Winding Effect.

The improvement of the load capacity of soft grippers has always been a challenge. To tackle this load capacity challenge, this work presents four novel types of high-load (HL) soft grippers that are bioinspired by bionic winding models. The winding models are found commonly in many animals and plants, where different winding patterns are used to grip different objects. Inspired by the winding models, we design four bionic winding structures that are driven by pneumatic artificial muscles (PAMs), and then four HL soft grippers are formed out of the winding structures. The inner cavities of the HL soft grippers contract after the PAMs are inflated, which enables objects to be wrapped to achieve gripping. Compared with most existing soft grippers, the HL soft grippers have a higher load capacity, and they can also grip various objects that have different shapes and stiffnesses without damaging them. In addition, in man-machine collaboration, operators can be in direct contact with them without being hurt. Our study helps lay the foundation for engineered systems with bionic winding structures.