A self-excited bistable oscillator with a light-powered liquid crystal elastomer
Journal
International Journal of Mechanical Sciences
Journal Volume
271
Start Page
109124
ISSN
00207403
Date Issued
2024
Author(s)
Abstract
The nonlinearity in the dynamics of a liquid crystal elastomer-based systems plays an important role when designing and controlling a responsive LCE-based smart system. In this work, we proposed an LCE-based bistable oscillator and investigated its self-excited oscillation behavior. The oscillator consists of a lumped mass, connected by two lateral helical springs, and one liquid crystal elastomer fiber spring which is subjected to a steady light illumination. After inserting the dynamic model of the light-powered LCE fiber into that of the oscillator, the nonlinear vibration response is obtained by using a fourth-order Runge-Kutta method. Different from the reported mono-stable limit circle modes, the self-vibration has a snap-through oscillation mode owing to an opto-mechanical coupling where the light energy can overcome the potential well of the mechanical part. Since the light illumination energy compensates the dissipative energy loss in each nonlinear vibration period, the nonlinear vibration of the LCE-based bistable oscillator is sustainable. We discuss the influence of both the linear and nonlinear parameters on the self-excited vibration response of the bistable oscillator. The nonlinear parameters of the lateral spring, such as the stiffness ratio and the length ratio, as well as the linear parameters of the LCE fiber, including the damping ratio, spring stiffness, light intensity, light contraction coefficient, and gravity, are all taken into consideration in our analysis. Our results reveal that the self-excited vibration can be controlled by adequately tuning these linear and/or nonlinear parameters. The investigation may pave a way for promising applications such as intelligent structural design, energy harvesting, sensing, actuating, and bio-mimic/bio-inspired system using the LCE fiber.
Subjects
Bistable Oscillation
Light-powered
Liquid Crystal Elastomer
Nonlinear Dynamic
Phase Trajectory
Potential Well
Damping
Elastomers
Energy Harvesting
Fibers
Liquid Crystals
Plastics
Runge Kutta Methods
Stiffness
Structural Design
Vibrations (mechanical)
Bi-stable Oscillators
Bistable Oscillation
Bistables
Light Illumination
Light-powered
Liquid Crystal Elastomers
Non-linear Parameters
Non-linear Vibrations
Phase Trajectory
Potential Wells
Energy Dissipation
Publisher
Elsevier Ltd
Type
journal article