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

9624949加文这个职业研究计划的主要目标是开发一个控制系统的地震结构振动抑制这是简单的实施，鲁棒的结构模型中的不确定性，需要很少的外部电源，并保证闭环稳定性。 为了实现这一目标，将具有可调刚度和阻尼的结构构件安装在集中参数结构系统中。 这些成员将利用电流变（ER）和磁流变（MR）材料。 这些材料在没有外部静电场或磁场的情况下表现得像牛顿流体，但在施加强场时迅速变成粘弹性塑性固体。 可控结构构件的模型将包括低剪切速率下ER和MR行为的详细模型。 ER和MR器件的实验将被用来完善的分析模型。 具有相互作用的ER或MR装置的结构的模型将用于导出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。 控制综合将通过使用各种控制方法来进行。 同伴教育计划的目的是捕捉年轻学生的兴趣，让他们有机会放纵自己的学术好奇心，并准备研究生在结构控制的生产性职业生涯。 一个讲座和便携式动手示范将准备在地区高中和小学提供。 强大的解决问题的工具将给予大学生计算机软件包。 本科生将有机会进行自己选择的研究或作为本研究计划的一部分。 设施将到位，为他们的项目提供实验室支持。 研究生将从杜克大学所有工程系协调的控制中受益。 当地产业将通过合作和暑期实习参与研究和教育计划。 这是96年的职业奖。 ***

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. ***