Phase transition and optimal actuation of active bilayer structures
Phase transition and optimal actuation of active bilayer structures
复制标题
活性双层结构的相变和最佳驱动
DOI：
10.1016/j.eml.2019.100467
复制
发表时间：
2019-05-01
影响因子：
4.7
通讯作者：
Cao, Changyong
中科院分区：
文献类型：
--
作者：
Liu, Yin;Cao, Yunteng;Cao, Changyong
主动双层结构在药物输送、软机器人和驱动器等领域具有巨大的应用潜力。本文研究了双层结构在双轴主动应变作用下的相变和最佳驱动。本文提出了一个理论模型来预测双层膜在大变形区的弯曲曲率，而不是传统的Kollishenko屈曲解。利用有限元法中的Riks路径跟踪程序来跟踪主动应变引起的突跳不稳定性，以确定双层中双稳态的相边界。基于模拟得到的弯曲曲率和能量图，详细讨论了从双稳态到单稳态的相变图以及通过改变主动应变产生突跳不稳定性的一般规律.利用平均曲率来表征驱动效率，我们发现主动应变的各向异性可以用来调整双层结构的弯曲角度和结构。所提出的模型和所获得的相图提供了一个潜在的指导，为未来的高性能双层为基础的驱动器和机器在广泛的应用。(C)2019爱思唯尔有限公司版权所有。
Active bilayer structures have great potential applications in the fields of drug delivery, soft robots and actuators. In this paper, we have investigated the phase transition and optimal actuation of bilayer structures under biaxial active strains. A theoretical model is developed to predict the bending curvature of the bilayer in the large deformation regime, instead of the traditional Timoshenko's buckling solution. A Riks path-following procedure in the finite element method is utilized to trace the active-strain induced snap-through instability to identify the phase boundaries of bistability in the bilayer. The phase transition diagram from bistability to monostability and the general requisites to generate a snap-through instability by varying active strains are thoroughly discussed based on the bending curvature and energy landscape from simulations. Using the average curvature to characterize the actuation efficiency, we find that the anisotropy of active strains can be utilized to tune the bending angle and configuration of bilayer structures. The presented model and the obtained phase diagram provide a potential guidance for future design of high-performance bilayer-based actuators and machines in a broad range of applications. (C) 2019 Elsevier Ltd. All rights reserved.