ABSTRACT

Nowadays, the soft material, dielectric elastomers (DEs) are being used for many engineering applications due to their exceptional properties like high strain rate sensitivity, low power consumption, capable of static force measurement and capability of changing dimensions when subjected to voltage. They have the ability of converting mechanical energy to electrical energy and vice versa. In this article, nonlinear dynamic behavior of viscoelastic tapered DE under mechanical and electromechanical loading is studied. A dynamic model based on standard linear solid model is incorporated for viscoelasticity. Strain energy density of the system is derived from Gent model of hyperelasticity. The tapered DE is analyzed with different values of damping coefficients, ratio of shear moduli of springs, width and height tapers. The effects of tapers greatly put an impact on the dynamic responses of the system. The tapered DEs exhibits damped vibration and weak nonlinearity with an increase in damping force. The dynamic stability of tapered DEs is also studied using phase diagrams, and the results indicated that with an increase in damping force, the dynamic stability changes from a state of aperiodic vibration to quasi-periodic vibration. It is also found that the resonant frequency and peak amplitude reduce with an increase in the damping force.

摘要

如今，软材料，介电弹性体（DEs）由于其卓越的特性（如高应变速率敏感性，低功耗，能够进行静态力测量以及在电压变化时具有改变尺寸的能力）而被用于许多工程应用。它们具有将机械能转换为电能的能力，反之亦然。在本文中，研究了粘弹性锥形DE在机械和机电载荷下的非线性动力学行为。基于标准线性实体模型的动态模型被引入以用于粘弹性。该系统的应变能密度来自超弹性的Gent模型。使用不同的阻尼系数值，弹簧的剪切模量比，宽度和高度锥度对锥形DE进行分析。锥度的影响极大地影响了系统的动态响应。随着阻尼力的增加，锥形DE表现出阻尼振动和弱非线性。还利用相图研究了锥形DE的动力稳定性，结果表明，随着阻尼力的增加，动力稳定性从非周期性振动状态变为准周期性振动。还发现，随着阻尼力的增加，谐振频率和峰值幅度减小。动态稳定性从非周期性振动状态变为准周期性振动。还发现，随着阻尼力的增加，谐振频率和峰值幅度减小。动态稳定性从非周期性振动状态变为准周期性振动。还发现，随着阻尼力的增加，谐振频率和峰值幅度减小。