Self-oscillation of a liquid crystal elastomer fiber-shading laminate system under line illumination

Abstract

Light-driven self-sustained systems are widely utilized in various applications, and constructing a self-sustained system typically necessitates a spatially non-uniform light field, which can be challenging to establish and often leads to insufficient light utilization. In this paper, we construct a self-oscillating liquid crystal elastomer fiber-shading laminate system under line illumination, which is modulated through a shading laminate with varying transmittance to achieve a displacement-dependent light field illuminated on the liquid crystal elastomer fiber. We present the general governing equations, then derive their asymptotic equations under shorter characteristic time conditions, conduct a bifurcation analysis and obtain analytical expressions for the amplitude and frequency of the self-oscillations. Furthermore, the influences of different system parameters on the bifurcation point, amplitude, and frequency are examined. The consistency between the numerical and analytical solutions of the system proves the reliability of the derivation. The use of the shading laminate provides a simple feedback mechanism, which makes the light field modulation more flexible, while concentrating the light on the liquid crystal elastomer fiber improves energy utilization. This provides convenience and guidance for various applications including autonomous, highly controlled light-driven soft robotics, energy harvesting, micromechanics, and other related fields.