Fast piezoelectric actuation of an elastomeric micropore

A viscoelastic membrane unit fabricated from thermoplastic polyurethane, with a formed single micropore, was interfaced to a piezoelectric actuator to demonstrate rapid actuation of the pore. Changes in through-pore conductance were measured as a function of the voltage applied to the actuator. The pore was opened and closed either in a stepwise fashion, or else made to oscillate between more and less open positions at up to 200 Hz. The step-driven response exhibited both a fast (<100 ms) majority component and a slow (∼1 s) minority component. The oscillatory method indicated that the majority component reached 95% of the low frequency (5 Hz) conductance amplitude in ∼5 ms, fast enough for a pore to close upon a particle driven by a 50 Pa pressure head. This advance in the rapid control of very small pores was achieved by reducing the amount of viscoelastic material between the pore and the source of actuation. This technique has potential for measurement and manipulation of micro- and nano-particles.     

压电驱动微型振动平台的仿真分析

针对航天领域一些微型零件的测试要求,设计了一种以压电元件为驱动源,结合柔性铰链机构的微型振动平台,建立了微型振动平台的有限元模型,模拟几种常见的控制波形,对平台在多点激励下的动态特性进行了仿真分析。结果表明,可以通过计算机设计复杂控制波形,使平台变换姿态或按一定规律振动。该文的仿真分析为平台的进一步研制提供了重要的参考依据。     

压电驱动微位移放大机构的分析与实验

针对航天微型扭杆性能测试装置用到的微小扭矩加载系统中的压电驱动微位移放大机构,建立了精确的有限元模型,对微位移放大机构在不同驱动力下的位移输出,利用有限元分析软件Nastran 2001进行了仿真分析,实验结果验证了仿真分析的准确性。结果表明：利用杠杆原理计算微位移放大机构的放大比会带来较大的误差,本机构中达到了50．6％,而有限元分析是行之有效的方法。