Thermal Response Kinetic Behavior Of Flat Moving Liquid Crystal Elastomer Fiber Oscillators

Due to the coupling between heat conduction and deformation,liquid crystal elastomer(LCE)fibers with fixed ends in an inhomogeneous temperature field are capable of self-oscillation,a phenomenon that can derive energy directly from a constant external environment to maintain periodic motion.In an inhomogeneous temperature field,a flat moving LCE fiber can perform self-excited oscillations under a given condition,so the dynamics of a flat moving LCE fiber in an inhomogeneous temperature field has a great scope for application.However,most of the current studies on elastic fiber bodies are stuck in the case where the external conditions are static;in fact,dynamic external conditions exist in more application scenarios in practice.Therefore,the study of elastic fibrous bodies under dynamic conditions is necessary if the direction of theoretical research is to be further adapted to practical applications.In this paper,we study the self-oscillation of the LCE fiber oscillator in the three cases of infinitely fast heat transfer,fast heat transfer,and constant heat transfer,and the specific effects of the main relevant parameters on the oscillation frequency,amplitude,and equilibrium position under three typical states of motion,namely,stationary,uniformly translational,and accelerated translational,in each case.In Chapter 2,the dynamic behavior of the translational LCE fiber oscillator in an inhomogeneous temperature field under the infinitely fast heat transfer case is studied.A theoretical model of a flat moving LCE fiber oscillator in a linear temperature field and its asymptotic relations at fast heat transfer are established,followed by the derivation of the control equations under infinitely fast heat transfer conditions through the theoretical model,and then the three typical cases of fiber oscillation at frame rest,uniform flat motion and uniform accelerated flat motion in the infinitely fast heat transfer case are studied using the control equations and MATLAB simulations,and it is found that eventually all cannot develop into periodic oscillations,and further studies give the specific effects of the main relevant parameters on the tip amplitude,reaction time and equilibrium position of the vibration;Chapter 3 investigates the dynamical behavior of the translational LCE fiber oscillator in an inhomogeneous temperature field in the case of fast heat transfer.The three typical cases of the fiber oscillator at frame rest,uniformly flat and uniformly accelerated flat motion in the fast heat transfer case are investigated by MATLAB simulations through theoretical models and asymptotic relations at fast heat transfer,and it is found that all can eventually develop into periodic oscillations,and further studies give the specific effects of the main relevant parameters on the amplitude,period and equilibrium position of the oscillations;Chapter 4 investigates the dynamical behavior of a flat moving LCE fiber oscillator in an inhomogeneous temperature field in the case of constant velocity heat transfer.Three typical cases of fiber oscillations at frame rest,uniform and uniformly accelerated advection in the case of constant velocity heat transfer are investigated by means of theoretical models and control equations and MATLAB simulations,which are found to eventually develop into periodic oscillations,and the specific effects of the main relevant parameters on the amplitude,period,and equilibrium position of the oscillations are given.This paper highlights the study of the dynamic case of LCE fibers,giving in detail the dynamical behavior of the flat moving LCE fiber oscillator,and these results are expected to provide some useful suggestions for the design and motion control in the field of micro-robots,energy harvesters and clinical surgery scenarios.