CAREER: Seismic Response Suppression Using Materials with Controllable Stiffness and Damping

9624949加文这一职业研究计划的主要目标是开发一种地震结构减振控制系统，该系统易于实施，对结构模型中的不确定因素具有健壮性，只需要很少的外部功率，并具有闭环系统稳定性。为了实现这一目标，在集总参数结构体系中安装具有可调刚度和阻尼力的结构构件。这些成员将使用电流变(ER)和磁流变(MR)材料。在没有外加静电场或磁场的情况下，这些材料的行为就像牛顿流体一样，但当施加强电场时，它们很快就会变成粘电塑料固体。可控结构构件的模型将包括低剪切率下ER和MR行为的详细模型。在ER和MR设备上的实验将被用来改进分析模型。具有相互作用的ER或MR装置的结构模型将被用来推导控制规则以抑制这些非线性系统中的振动。控制的性能将通过变形和绝对加速度的衰减来判断。将采用各种控制方法进行控制综合。与之配套的教育项目旨在吸引年轻学生的兴趣，让他们有机会沉迷于自己的学术好奇心，并为研究生在结构控制领域取得成功的职业生涯做好准备。将准备在该地区的高中和小学进行讲座和便携式动手演示。将向本科生提供强大的问题解决工具。本科生将有机会进行他们自己选择的研究或作为这个研究计划的一部分。设施将到位，为他们的项目提供实验室支持。研究生将受益于杜克大学所有工程系协调控制的累积体。当地企业将通过合作和暑期实习参与研究和教育项目。这是96财年的职业奖项。***

9624949 Gavin The primary goal of this career research program is to develop a control system for seismic structural vibration suppression which is simple to implement, robust to uncertainties in the structural model, requires very little external power, and has guaranteed closed loop stability. Structural members with adjustable stiffness and damping will be installed in a lumped parameter structural system to achieve this goal. These members will make use of electrorheological (ER) and magnetorheological (MR) materials. These materials behave like Newtonian fluids in the absence of external electrostatic or magnetic fields but quickly become visco-electic plastic solids when strong fields are applied. A model for the controllable structural members will include a detailed model for ER and MR behavior at low shear rates. Experiments on ER and MR devices will be used to refine the analytical models. Models of a structure with interacting ER or MR devices will be used to derive control rules to suppress vibrations in these nonlinear systems. The performance of the control will be judged by the attenuation of deformations and absolute accelerations. Control synthesis will be carried out by using various control methods. The companion educational program is designed to capture the interest of young students to give them the opportunity to indulge their academic curiosities and to prepare graduate students for a productive career in structural control. A lecture and portable hands-on demonstration will be prepared to be delivered at area high schools and elementary schools. Powerful problem solving tools will be given to undergraduates computer packages. Undergraduates will have opportunities to conduct research of their own choosing or as part of this research program. Facilities will be in place to provide laboratory support to their projects. Graduate students will profit from a cummiculum in control that is coordinated across all engineering departm ents at Duke University. Local industries will be involved in both the research and education programs through collaborations and summer internships. This is a FY 96 Career award. ***