Nonlinear Dynamics of Multi-Mesh Gear Systems

Prof. Robert ParkerDepartment of Mechanical EngineeringOhio State UniversityGear vibration dominates helicopter cabin noise, which can exceed 110 dB. Gear vibration is a major concern in numerous other applications including aerospace, automotive, wind turbines, high-speed machinery, manufacturing, and more. Despite gears' long history, scientific study of their dynamics has been concentrated in the last 40 years, and the pervasive impact of nonlinearities and parametric instability in gear vibration has been realized only in the last decade. Mathematical models are emerging to incorporate these critical aspects. Planetary gears and other systems having multiple interacting tooth meshes exhibit especially interesting dynamics that remain largely unexplored. Nonlinearity from tooth contact loss and parametric instability from varying contact conditions as the gears rotate are essential features of complex phenomena observed in practice. After giving industrial examples motivating the research, the presentation will focus on modeling and analysis of the nonlinear dynamics of planetary gears using asymptotic and finite element/contact mechanics methods. In addition to illustrating and explaining the rich range of nonlinear dynamics that emerge, the analytical approximations generate results with clear practical implications. An ambitious $2.1M experimental gear dynamics program with specialized facilities that are unique worldwide will also be discussed.Professor Robert Parker has been at the Ohio State Department of Mechanical Engineering since 1996. He received his M.S. and Ph.D. degrees from the University of California, Berkeley. His research investigates problems on the dynamics, vibration, and stability of mechanical systems with particular focus on high-speed devices. He has held visiting research appointments at INSA Lyon (France), Risoe National Lab (Denmark), NASA Glenn Research Center, the University of Technology-Sydney, and Tokyo University. He worked for two years in the Spacecraft Dynamics division of The Aerospace Corporation in Los Angeles. He consults internationally on vibration problems in numerous industries.Prof. Parker has received over $5M of research funding from the National Science Foundation, U.S. Army Research Office, NASA, National Rotorcraft Technology Center, General Motors, Ford, Boeing, Sikorsky, and other companies. Prof. Parker is a Fellow of ASME and AAAS. He was one of a select group invited to National Academy of Engineering Frontiers of Engineering Symposia in the US and Germany. He received the Presidential Early Career Award for Scientists and Engineers (PECASE) in 1999, which is "the highest honor awarded by the U.S. government to scientific researchers early in their careers," as well as the NSF CAREER and Army Young Investigator Awards.

Location: Seaver Science Library, Rm 150

Audiences: Everyone Is Invited

Contact: April Mundy