报告一：

报告主题：Eigenvalue Assignment by Structural Modification

报告时间：2024年10月28日 上午9:00-10:30

报告地点：A18-705

内容介绍：This lecture introduces the fundamental principles of eigenvalue assignment in mechanical systems through structural modifications. The focus will be on utilizing measured receptances to achieve desired eigenvalue changes, leveraging both rank-1 and higher rank modifications. Key techniques, such as modifications using added structural elements like beams, will be discussed. An illustrative example of aeroelastic stability analysis will demonstrate the practical application of these methods. The lecture will highlight the implications of these modifications in controlling the dynamic behavior of structures and enhancing system stability.

报告二：

报告主题：Eigenvalue Assignment by Active Control

报告时间：2024年10月28日 上午10:30-12:00

报告地点：A18-705

内容介绍：Building on the structural modification methods covered in the first lecture, this session explores eigenvalue assignment using active control strategies. Both single-input and multiple-input control schemes will be introduced, with a focus on the design of minimum-norm controllers. The lecture will discuss how active control can effectively assign eigenvalues to meet stability and performance requirements, using flutter control of a model wing as a key example. Practical considerations in controller design for dynamic systems will be emphasized, highlighting the synergy between theoretical development and real-world applications in mechanical and aerospace structures.

报告三：

报告主题：Sensitivity-Based Model Updating

报告时间：2024年10月29日 上午9:00-10:30

报告地点：A18-529

内容介绍：This lecture introduces the fundamentals of model updating using the sensitivity method. Finite Element (FE) models often deviate from experimental results due to assumptions and approximations in material properties, boundary conditions, or mass distribution. The sensitivity method corrects these discrepancies by adjusting model parameters based on the sensitivity of eigenvalues and eigenvectors to small parameter changes. Regularization techniques such as the L-curve method are used to mitigate ill-conditioning in the sensitivity matrix. This lecture will include an example application to the Lynx helicopter model, demonstrating how sensitivity-based model updating enhances model accuracy and reliability in aerospace structures.

报告四：

报告主题：Stochastic Model Updating with Sensitivity Methods

报告时间：2024年10月29日 上午10:30-12:00

报告地点：A18-529

内容介绍：Building on the deterministic approach in Lecture 3, this session explores stochastic model updating using sensitivity methods. Real-world structures exhibit variability due to factors like manufacturing tolerances, leading to randomness in their dynamic responses. Stochastic model updating accounts for this variability by incorporating probabilistic models such as the Kriging predictor and Polynomial Chaos Expansion (PCE) to represent uncertain input parameters. The lecture will highlight case studies involving real mechanical systems, demonstrating how sensitivity-based stochastic methods are applied to quantify uncertainty and improve model robustness in industrial applications.

主办单位：航空学院、航空航天结构力学及控制全国重点实验室、校科协、国合处

报告人简介：

John Mottershead has BSc and PhD degrees in Mechanical Engineering and was awarded the DEng degree by the University of Liverpool, where he is the Alexander Elder Professor in Applied Mechanics.  His research interests include FE model updating, active vibration control and servoaeroelasticity. He has published several hundred papers in international journals and conference proceeding and his industrial collaborations include, from the motor industry BMW, Fiat, Ford and Peugot-Citroen, and from the aerospace industries Leonardo (Helicopter Division), Airbus UK and Rolls-Royce. He is the Editor-in-Chief of Mechanical Systems and Signal Processing.