超弹性介电型EAP圆柱形驱动器变激励电压下动态响应分析

Dynamic responses of a hyperelastic dielectric EAP cylindrial actuator under varying excitation voltage

超弹性电活性聚合物(electroactive polymer,EAP)圆柱形驱动器的动态特性是进行合理设计、使用及优化驱动器的重要依据。结合介电型EAP机电耦合方程,构建了驱动器轴向线性运动的动力学方程。通过计算得到驱动器的电压-轴向位移曲线,研究了驱动器在准静态点附近的稳定性。最后,分析了驱动器在施加阶跃和周期电压激励时的动态响应。结果表明,在有效工作范围内驱动器是稳定的,阶跃电压激励使驱动器在准静态点附近产生轴向振动,周期电压使驱动器产生包含自振的拟周期轴向振动。进一步分析表明,阶跃电压激励更易导致驱动器的电击穿失效。

The dynamic performance of a dielectric electroactive polymer（ EAP） cylindrical actuator was a basis for its reasonable design,operation and optimization. Combined with the dielectric EAP electromechanical coupled equation,the dynamic equation for the axial linear movement of the actuator was deduced. The relation between the axial displacement of the cylindrical actuator and the applied voltage was obtained with the numerical solution to the dynamic equation,and the stability neigh bouring the quasi static point was analyzed. Finally,the dynamic responses of the actuator to applied step and periodic voltages were studied. The results showed that the actuator is stable in its effective working range,the sudden step voltage can cause the actuator＇s axial vibration around the quasi-static position,and the periodic voltage generates its quasi-periodic axial vibration including its natural oscillation; furthermore,the sudden step voltage is easy to cause the actuator＇s electric breakdown and damage.