Monolithically Assembled 3D Soft Transformable Robot

Abstract

With the growing demand for soft robots capable of various degrees of locomotion based on reversibly actuating liquid crystalline networks (LCNs), the fabrication of complex 3D architectures from 2D LCN films via shape reconfiguration and/or assembly techniques are studied recently. However, once a system is formed and fixed into a specific 3D structure, only certain movements can be implemented using the fixed structure, and disassembly into the original 2D films is challenging. Therefore, studies to overcome this irreversible fabrication process become increasingly important. Herein, an effective and simple preparation of static and dynamic covalent dual-cross-linked, photo-controllable LCN (pc-LCN) films as building blocks for lego-like, monolithically assembled 3D soft transformable robots is presented. By tailoring the static and dynamic covalent linkages in the networks, pc-LCN films can be readily reconfigured and assembled into complex 3D structures under ultraviolet (UV) irradiation. Such monoliths can also be disassembled into their constituent building block films and reassembled into different architectures under the same UV stimulation. Moreover, by adopting selective visible-light-responsive dopant dyes to actuate pc-LCN building blocks, 3D soft transformable robots with versatile motion capabilities, including rolling, gripping, and cargo transport in multiple directions, are demonstrated.