Engineering Creativity Award: Piezoelectric Damping of Flexible Structures

轻型柔性机械臂在当前和未来的空间活动中发挥着重要作用。现有的一个例子是航天飞机远程操纵系统（RMS），未来的计划要求其他类似RMS的武器自动化空间操作，如装配。需要解决的一个关键问题是，如何抑制由于RMS系统的长距离和轻量化结构所引起的振动。本研究项目的目的是研究压电薄膜涂层应用于柔性结构构件时的潜在被动阻尼特性。提出利用具有压电特性的聚偏氟乙烯（PVDF）聚合物薄膜，通过电流来消散振动能量。一层PVDF薄膜应用于振动构件的表面将产生电流，由于机械变形。电流可以通过无源阻抗，从而消耗振动能量，从而减少振动。利用PVDF膜被动减振是一种新的研究思路。最终目标是为RMS或类似的柔性机械臂提供易于实现的修改，从而在不显著增加系统成本、重量和控制复杂性或计算成本的情况下提高性能。

Lightweight flexible manipulators are playing an important role in current and future space activities. An existing example is the Shuttle Remote Manipulator System (RMS) and future plans call for other RMS-like arms to automate space operations, such as assembly. A key problem to be resolved is to dampen the vibrations caused by the necessary long reach and lightweight construction of the RMS system. The objective of this research project is to investigate the potential passive damping characteristics of piezoelectric film coatings when applied to flexible structural members. It is proposed to use a polymer film, PVDF, which has piezoelectric characteristic, to dessipate vibrational energy by means of an electric current. A layer of PVDF film applied to the surface of a vibrating member will generate an electric current due to mechanical deformations. The electric current can be passed through a passive impedance thus dessipating vibrational energy thereby reducing the vibrations. Using PVDF film to passively dampen vibrations is a new idea which has not been investigated. The ultimate goal is to provide an easily implemented modification to the RMS, or similar flexible manipulator that enhances performance without significantly increasing system cost, weight, and complexity of control or computational costs.