Title: Recent Advances in Dynamic System Research

Reporter: Professor Weidong Zhu

Department of Mechanical Engineering

University of Maryland, Baltimore County

Abstract:

Some interesting results on vibration and stability of distributed structural systems, vibration-based damage detection, and infinitely variable transmission are reviewed. Vibration and stability of translating media with time-varying lengths and/or velocities are addressed. Two types of dynamic stability problems are considered: dynamic stability of translating media during extension and retraction, and parametric instabilities in distributed structural systems with periodically varying lengths and/or velocities. The incremental harmonic balance method is used and modified to handle periodic responses of high-dimensional nonlinear models and their stability and bifurcations, as well as quasi-periodic responses. A new spatial discretization and substructure method, which ensures that all matching conditions of distributed components are satisfied, and hence uniform convergence of solutions, are discussed. New formulations of flexible multibody dynamics are developed with application to elevator traveling cables. Nonlinear wave propagation in phononic structures and elastic wave cloaking are discussed. Two major challenges in model-based damage detection are addressed: accurate modeling of structures and development of a robustness algorithm for identifying locations and extent of damage. Non-model-based damage detection methods using scanning laser vibrometry are also presented.

Brief Biography

Weidong Zhu is a Professor in the Department of Mechanical Engineering at the University of Maryland, Baltimore County, and the founder and director of its Dynamic Systems and Vibrations Laboratory and Laser Vibrometry Laboratory. He received his PhD degree in Mechanical Engineering from the University of California at Berkeley in 1994. He is a recipient of the 2004 National Science Foundation CAREER Award, the 2007 American Society for Nondestructive Testing Fellowship Award, the 2008 ChangJiang Scholar Chair Professorship in General Mechanics from the Ministry of Education of China, the 2009 Daily Record's Maryland Innovator of the Year Award. He has been an ASME Fellow since 2010, was an Associate Editor of the ASME Journal of Vibration and Acoustics from 2007-2014, and is a Subject Editor of the Journal of Sound and Vibration. His research spans the fields of dynamics, vibration, control, applied mechanics, structural health monitoring, wind energy, and metamaterials, and involves analytical development, numerical simulation, experimental validation, and industrial application. He has published over 120 SCI-indexed journal papers in these fields.