介电弹性体圆柱形驱动器机电耦合致动过程分析

Analysis of Electromechanical Coupling Activation Process of Dielectric Elastomer Cylindrical Actuator

驱动器薄膜施加高压直流电后产生的轴向力差能使圆柱形驱动器伸长。为研究介电弹性体圆柱形驱动器的动态反应,本文对其机电耦合致动原理及过程进行了分析。圆柱形驱动器的机电耦合致动过程类似于蠕变过程,提出一种广义Voigt线性粘弹性模型来对其进行描述,并对计算结果与试验之间产生误差的主要原因进行分析。根据驱动器机电耦合致动过程中驱动器的准静态位移的非线性及轴向应力的变化对原模型进行改进。试验表明,在驱动器工作电压范围内,改进的广义Voigt模型能较好地描述驱动器机电耦合致动过程,此模型可用于介电弹性体圆柱形驱动器的性能预测和优化。

The axial force difference aroused from applying high DC voltage on the actuator film makes the cylindrical actuator elongate. In order to study the dynamic response of dielectric elastomer cylindri- cal actuator, the principle and the process of electromechanical coupling activation are analyzed. The electromechanical coupling activation process of cylindrical actuator is similar to creep. A general linear viscoelastic Voigt model is put forward to describe the process and the principal reasons for the error be- tween calculated result and experimental one are discussed. The model is modified according to the non- linear quasi-static displacement and the axial stress change of actuator during its actuation process. Ex- periment results show that the modified general Voigt model is suitable to characterize the elec- tromechanical coupling process of cylindrical actuator within the working voltage range. Therefore,the presented model can be used for prediction and optimization of the performance of dielectric elastomer cylindrical actuators.