Light‐Driven Continual Oscillatory Rocking of a Polymer Film

Achieving oscillatory motion in polymers without requiring on/off switching of stimuli is a current challenge. Hereby, a free‐standing liquid crystal polymer (LCP) is demonstrated to undergo a sustained oscillatory motion when triggered by light, moving back and forth, resembling the motion of a rocking‐chair. Two polymer films having different azobenzene photo‐switches have been studied, revealing photoswitch requirements as well as illumination conditions necessary to sustain oscillations. The motion presented here shows how feedback loops involving light‐triggered actuation, self‐shadowing and a shifting center of gravity can be utilized to achieve self‐sustained motion in free‐standing polymers.