A Light-Spurred Self-Oscillator of Liquid Crystal Elastomer with Tunable Shielding Area under Constant Irradiation

Abstract

Self-oscillation systems utilizing soft active materials are gaining attention for their potential in applications like soft actuators, sensors, energy harvesters and micro/nano machines. In this study, a self-oscillator of liquid crystal elastomer (LCE) with tunable shielding area is constructed, which encompasses a light-responsive LCE fiber and a tunable shielding tube with mass. A nonlinear dynamic model for light-spurred self-oscillator motion is proposed and its dynamic behavior is investigated. Computational results reveal that the LCE oscillator exhibits two distinct motion manners: self-oscillation state and static state. The self-oscillation manner is sustained from the energy competition between absorbed light energy and damping dissipation. The triggering conditions for self-oscillation manner are obtained and the effects of various system parameters on the amplitude and frequency of self-oscillation are probed in detail. In contrast to other existing self-oscillation schemes, the constructed self-oscillator system is advantageous in some respects, e.g. simple structure, easy fabrication, and high reliability. In addition, the insights gained from this study advance our understanding in self-oscillatory phenomena and offer new design concepts in the fields of soft actuators, sensors, energy harvesters and micro/nano machines.