Laser-induced kirigami structures of liquid crystal elastomers for multimodal morphing

Abstract

Kirigami offers a versatile framework for transforming planar films into three-dimensional (3D) intricate structures, which is instrumental in developing liquid crystal elastomer (LCE) soft robots. These robots can dynamically alter their shapes to accommodate various functionalities. By meticulously designing the geometries of cuts, a range of out-of-plane configurations can be induced, resulting in an expanded repertoire of deformation modes. In this study, we utilize a commercially available laser engraver for the precise alignment of anisotropic kirigami azobenzene (azo) LCEs, streamlining the manufacturing process of cuts with diverse geometric shapes. The resulting actuators possess a predetermined alignment within defined geometric regions, enabling them to exhibit a variety of complex shapes when stimulated by light. Furthermore, polyimide (PI) films can be selectively transformed into graphene-coated films through surface carbonization using the 450 nm laser from the engraver, resulting in bilayer kirigami structures with enriched shape-changing capabilities. These highly maneuverable soft actuators demonstrate distinct functionalities, such as grasping and transporting micro-cargo. We anticipate that the evolution of intelligent soft robotics, characterized by multimodal morphing and seamless functional integration, will be propelled by laser-induced kirigami azo-LCEs.