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.