周期光照下液晶弹性体简支梁的振动响应研究  

Vibration response of a simply supported beam of liquid crystal elastomer under periodic illumination

作　　者：赵俊 华立夫 李凯 ZHAO Jun;HUA Li-fu;LI Kai(Department of Civil Engineering,Anhui Jianzhu University,Hefei 230601,China)

机构地区：[1]安徽建筑大学土木工程学院,合肥230601

出　　处：《计算力学学报》2024年第2期283-289,共7页Chinese Journal of Computational Mechanics

基　　金：安徽省自然科学基金优秀青年项目(2208085Y01);国家自然科学基金面上项目(12172001)资助.

摘　　要：液晶弹性体(LCE)因其具有快速的光热响应和可逆变形等特性,在能量转换、软机器人和非接触控制等领域具有广泛的应用前景。本文利用液晶弹性体在外部光刺激下可与机械变形耦合的特性,建立了LCE简支梁的动态模型,研究了其在周期光照下的弯曲振动现象。首先建立了LCE简支梁的光驱动控制方程,然后通过振型叠加法获得方程的半解析解,再用Matlab软件编程计算其变化规律。计算结果表明,周期光照可以使LCE简支梁发生周期性振动,梁跨中的振动幅值可以通过阻尼因子、热弛豫时间、光照强度、光照周期和光照时间率来调节,振动平衡位置可以通过光强与热弛豫时间来调节,振动反应时间可以通过热弛豫时间与阻尼来调节。本文结果对光驱动运动的控制和光机能量转换系统的设计具有一定的指导意义。A liquid crystal elastomer(LCE)has a wide range of applications in energy conversion,soft robotics and non-contact control because of its properties such as fast photothermal response and reversible deformation.In this paper,the dynamic model of a simply-supported LCE beam is established to study its bending vibration phenomenon under periodic light illumination by taking advantage of the property that a liquid crystal elastomer can be coupled with mechanical deformation under external light stimulation.The light-driven control equation of the simply supported LCE beam is firstly established,and then the semi-analytic solution of the equation is obtained by the vibration superposition method,and then the change law is programmed by Matlab software.The numerical results show that the periodic light can cause the simply supported LCE beam to vibrate periodically,the vibration amplitude in the beam span can be adjusted by damping,thermal relaxation time,light intensity,light period and light rate,the vibration equilibrium position can be adjusted by light intensity and thermal relaxation time,and the vibration response time can be controlled by thermal relaxation time and damping.The results of this paper have some guidance significance in the control of light-driven motion and the design of light-mechanical energy conversion system.

关 键 词：液晶弹性体 可控振动 周期性光照 振型叠加法 

分 类 号：O321[理学—一般力学与力学基础]