Reporting time: October 23, 2023 (Monday) 9:30-11:30

Reporting location: The first lecture hall of the new building of the School of Management

Speaker: Professor Gabor Stepan

Work Unit: Budapest University of Technology and Economics

Organizer: School of Automotive and Transportation Engineering

Report introduction:

Shimmy is a hard-to-predict vibration phenomenon of towed rolling wheels. Although it appears with low probability, it may cause catastrophic accidents. Low order models of shimmying wheels with single contact point and Coulomb friction show the fundamental phenomenology. Local and global dynamic analyzes explore parameter regions with bi-stability, isola, chaotic and transient chaotic oscillations. If there is pneumatic tire on the wheel, a certain time delay effect becomes relevant in the nonlinear dynamics of the system. The experimentally detected micro-shimmy onset is explained by carrying out a non-smooth bifurcation analysis that is related to the nonlinear effect of partial slipping within the tire/ground contact region.

Brief introduction of the reporter:

Professor Gabor Stepan, professor of the Department of Applied Mechanics at the Budapest University of Technology and Economics, Hungary, academician of the Hungarian Academy of Sciences, academician of the European Academy of Sciences, academician of the International Academy of Production Engineering (CIRP), foreign academician of the Estonian Academy of Sciences, former chairman of the Department of Science and Technology of the Hungarian Academy of Sciences, former chairman of the International Theory and Executive director and committee member of the Application Alliance (IUTAM). Professor Stepan is a well-known scholar in the international field of applied mechanics. He has won the Thomas K. Caughey Award of the American ASME Society of Mechanical Engineers, the Szechenyi Prize, Hungary’s highest science and technology award, and was awarded Hungary’s most prestigious Bolyai Award in 2023. The former The winner is Katalin Karikó (2023 Nobel Prize), the inventor of the new coronavirus vaccine. Professor Stepan’s main research areas include the theory and engineering applications of nonlinear dynamics, vibration and time-delay systems, such as stability and bifurcation theory, high-precision cutting, wheel oscillation, vehicle dynamics control, traffic dynamics, and robot vibration. and stability, human and robot balance issues, etc. Professor Stepan has long-term cooperation and friendship with the Chinese academic community. He serves as an honorary professor at Nanjing University of Aeronautics and Astronautics. He won the "Jiangsu Friendship Award" in 2020 and was invited to participate in the New Year Symposium of Foreign Experts hosted by Premier Li Keqiang and the Ministry of Science and Technology's 2035 Medium and Long-term Development planning advice meeting.