建立了悬臂梁结构半电极含金属芯压电纤维新型压电弯曲驱动器的理论模型。根据第一类压电方程,推导出自由端位移、夹持力和弯曲共振频率的解析表达式,分析了金属芯性能和半径对这3个参数的影响,并把理论计算结果和有限元分析结果进行了比较。实验结果表明,悬臂梁结构半电极含金属芯压电纤维弯曲驱动器的自由端位移可达589 μm,夹持力可达427 μN,一阶弯曲共振频率为28 Hz,有限元分析结果和理论值基本吻合,说明这种驱动器有较大的端部位移、较小的夹持力和较低的弯曲共振频率。

The mechanical mode of an Half coated Metal core Piezoelectric Fiber (HMPF) actuator is established. According to the constitutive piezoelectric equations, the analytical expressions of the tip deflection, blocking force and the natural frequencies are derived. The effect of the metal core on those properties of HMPF actuator is investigated based on the numerical results of the equations and FEM. The experimental results indicate that the maximum tip deflection of cantilevered HMPF, maximum blocking force and the first resonance frequency are 589 μm,427 μN and 28 Hz,respectively, FEM results are coincident with theoretical values on the whole. The results show that the actuator can give a big deflection, a small block force, and a low resonance frequency.