Optical Manipulation and Manufacturing Strategies of Intelligent Springs

As morphing devices and technologies become smaller and more complex, an emerging paradigm is the design of smart materials and structures to function as mechanical units. Recent works in the field have shown a variety of stimuli-responsive materials in multi-dimensional structures for many robotic components including actuators and sensors. We believe that the key to utilizing the intelligence of materials lies in designing materials chemistry and processing to extend manipulation and manufacturing capabilities. Here, we discuss optical manipulation and manufacturing strategies to create intelligent springs. In the first part, we discuss the all-optical manipulation of azobenzene-functionalized crystallized liquid crystal elastomers (AC-LCEs) for optomechanical actuators. Based on the synthesis and processing approaches in AC-LCEs, the optomechanical actuators combine robust mechanical properties and shape-morphing capabilities to enable 50% of linear reversible strain in an isothermal manner. In the second part, we introduce unconventional manufacturing of three-dimensional laser-induced graphene springs (LIG-S) for electromechanical applications. By a single scanning of laser on a polyimide substrate, intensive pressure created by pyrolysis induces exfoliation of 3D helical LIG-S in seconds, similar to wood or metal shavings observed in traditional machining processes, thus enabling mass production of macroscale structured LIG-S.