GOALI/Collaborative Research: Understanding and Controlling Variation Propagation in Periodic Structures: From Geometry to Dynamic Response

这项合作研究的目的是了解和控制周期性结构中产品几何形状与其动态响应之间的变异传播。制造过程本质上是不精确的，生产的产品几何形状各不相同。几何形状的变化不仅有害地影响最终装配的适合性，而且在许多情况下还影响最终产品的功能性。在这项研究中，我们将建模和分析周期结构中从制造零件几何形状到其动态响应的变化传播，从而提供通过控制零件几何形状的均值和偏差来减轻不良动态响应的指导方针。该方法包括两个方向的变化传播分析：(1)在正向预测中，基于密集测量来表征制造产品的几何变化，然后计算动态响应的概率分布。(Ii)在反向分析中，使用异常动力响应作为输入，识别出一组局部几何特征，这些局部几何特征在修改后可以减轻不良动力响应。如果成功，这项研究将对各种周期性结构产品产生积极影响，包括航空发动机和发电设备中的叶片盘，高速加工中的刀具，以及空间天线等。通过与通用电气的合作，这项研究将直接惠及使用这些周期性结构的航空航天、汽车和制造业等一系列行业。通过综合研究、教育和外展活动，该项目将为从高中到研究生院的学生提供变异传播和减少的高级知识，并将增强国内学生？对科学和工程的兴趣，因此加强了我们在全球劳动力中的竞争力。

The objective of this collaborative research is to understand and control the variation propagation between product geometry and its dynamic response in periodic structures. Manufacturing processes are inherently imprecise, producing products that vary in geometry. The geometry variation detrimentally impacts not only the fitness of the final assembly, but also in many cases the functionalities of the final product. In this research, we will model and analyze the variation propagation in periodic structure from the manufactured part geometry to its dynamic response and then to provide guidelines on mitigating the undesirable dynamic response via controlling the mean and variation of part geometry. The proposed methodology includes variation propagation analysis in two directions: (i) In the forward prediction, the geometry variation of the manufactured products is characterized based on dense measurements, and then the probabilistic distributions of the dynamic responses are computed. (ii) In the backward analysis, using the abnormal dynamic response as input, a group of local geometric features that, upon modification, can mitigate the undesirable dynamic response are identified. If successful, this research will positively impact a variety of periodic structural products, including bladed-disks in aero-engines and power generation equipment, cutting tools in high speed machining, and space antenna, etc. Through the collaboration with General Electric, this research will directly benefit a host of industries such as aerospace, automotive and manufacturing industries where these periodic structures are used. Through its integrated research, education and outreach activities, this project will provide advanced knowledge in variation propagation and reduction for students from high schools to graduate schools and will enhance domestic students? interest in science and engineering and therefore strengthen our competitiveness in the global workforce.