Inspired by Physical Intelligence of an Elephant Trunk: Biomimetic Soft Robot With Pre-Programmable Localized Stiffness

Soft robots exhibit promising dexterity and adaptability for manipulation because of their high compliance. However, the existing soft robots with invariant stiffness hardly interact with cluttered environments with varying curvatures. In this study, inspired by the maneuverability of an elephant trunk, we proposed a pneumatic soft robot comprised of soft pneumatic actuators and interference plates. By implementing interference plates in diverse patterns, the localized stiffness of our robot can be pre-programmed. To quantify the availability of localized stiffness regulation, we constructed four typical assembly fashions strengthened by the interference plates, and predicted robot profiles by simulation that was validated via experiments. We demonstrated the application of our soft robot with localized stiffness regulation in a variety of scenarios demanding specific configurations. Our design paradigm not only uncovers the potential methodology for regulating robotic curvature precisely, but may inspire next-generation soft robots integrating specified structural and material characteristics learned from natural intelligence.