Light‐Driven Folding Liquid Crystal Elastomer Catapult with Improved Morphing Velocity

Abstract

As a typical behavior of releasing energy in a short time, catapulting is a way for organisms to adapt to complex and changeable environments, such as crossing terrain obstacles and spreading seeds. The essence of catapulting behavior is that plants and animals use their structural characteristics to control elastic strain energy locking, triggering, and releasing under external stimulation. At present, bistable or multistable structures are attractive for optimizing the system energy and improving the performance of liquid crystal elastomer (LCE) soft actuators. However, the overelaborate designation of such structures makes it a great challenge to achieve fast morphing LCE soft actuators. Here, a light‐driven azobenzene liquid crystal elastomer (azo‐LCE) soft actuator mimicking the catapulting behavior of fern sporangia is reported. 2D azo‐LCE monoliths are simply folded to construct V‐shaped structures as 3D catapults, which exhibit higher morphing velocity upon UV light, and the morphing velocity is related to the aspect ratio of films. Furthermore, asymmetric morphing behavior occurs by constructing localized UV irradiation conditions, which greatly improves the morphing velocity. It is envisioned that the origami‐inspired azo‐LCE catapults can be further designed as the throwing component in fast‐morphing soft robots for the remote delivery of microcargoes.