Resonances of Nonlinear Mechanical Systems: a Nonlinear Normal Mode Perspective by Gaetan Kerschen, June 2021

Resonances of Nonlinear Mechanical Systems: a Nonlinear Normal Mode Perspective

Gaetan Kerschen

Space Structures and Systems Laboratory

Aerospace and Mechanical Engineering Department

University of Liège, Liège, Belgium

Email: g.kerschen@uliege.be

June 8, 2021

Abstract:

The concept of resonance is central in structural dynamics, because the maximum amplitude at which a system or a product vibrates occurs at resonance frequencies. Unlike linear systems, nonlinear systems can exhibit different types of resonances including primary, superharmonic, subharmonic and isolated resonances. In this presentation, we show how nonlinear modal analysis, and, specifically, the numerical computation and experimental identification of nonlinear normal modes, can be exploited for uncovering and understanding nonlinear resonances. A real-life satellite structure serves to illustrate the practical usefulness of nonlinear normal modes.

Biography:

Gaëtan Kerschen completed his Ph.D. degree in Aerospace Engineering from the University of Liège in Belgium in 2003. In 2003 and 2004, he was a visiting postdoctoral fellow at National Technical University of Athens and at the University of Illinois at Urbana-Champaign. Since 2007, he has been a faculty member at the University of Liège, where he is a professor in the Department of Aerospace and Mechanical Engineering. His expertise is primarily in the area of structural dynamics and orbital mechanics. He is the recipient of several international awards including two European Research Council (ERC) grants, the Doak Award from the Journal of Sound and Vibration and the SAGE Publishing Young Engineer Award. He was one of the principal investigators of the OUFTI-1 nanosatellite launched by the Soyuz rocket in 2016. He is the co-founder of NOLISYS, a startup company which provides solutions and software for nonlinear vibrating systems.