Printing Untethered Self-Reconfigurable, Self-Amputating Soft Robots from Recyclable Self-Healing Fibers

Abstract

Regarding the challenge of self-reconfiguration and self-amputation of soft robots, existing studies mainly focus on modular soft robots and connection methods between modules. Different from these studies, this study focus on the behavior of individual soft robots from a material perspective. Here, a kind of soft fibers, which consist of hot melt adhesive particles, magnetizable microparticles, and ferroferric oxide microparticles embedded in a thermoplastic polyurethane matrix are proposed. The soft fibers can achieve wireless self-healing and reversible bonding of the fibers by eddy current heating and can be actuated by magnetic fields. Moreover, the soft fibers are recyclable and printable. Building on this material foundation, an integrated material-structure-actuation printing strategy using soft fibers for the design and fabrication of soft robots are reported. The robots printed by this strategy can achieve their untethered motions and wireless self-healing. Soft gripper, soft crawling robot, and soft multi-legged robot, are then fabricated which demonstrates the self-healing, self-reconfigurable, self-amputating, and sustainable performances of soft robots so as to adapt to different environments and tasks. This integrated material-structure-actuation printing strategy using soft fibers is universal, easy to implement, and mass-manufactured, opening a door for sustainable, eco-friendly, untethered, self-reconfigurable, self-amputating soft robots.