Despite their long history, scientific study of planetary gear dynamics has been concentrated in the last 20 years. Planetary gears are an example of a cyclically symmetric system, and this cyclic symmetry leads to unusual vibration features in their modal properties and dynamic response. This talk will explore these unique vibration phenomena. Experiments confirming the behaviors will be described. These planetary gear behaviors represent what occurs in general cyclically symmetric systems (e.g., bladed disk assemblies and helicopter rotors), and those generalizations will be discussed. The first part of the presentation will discuss industrial examples motivating the work. The presentation will then briefly describe mathematical, finite element, and experimental approaches to planetary gear vibration analysis. Finally, we will illustrate and explain the range of cyclic symmetry phenomena and how the findings generate results with useful practical implications.

 

From 2012 Prof. Parker is the L. S. Randolph Professor in the Department of Mechanical Engineering at Virginia Tech. Previously he was a University Distinguished Professor and the Executive Dean at the University of Michigan-Shanghai Jiao Tong University Joint Institute. He received his M.S. and Ph.D. degrees from the University of California, Berkeley.

Prof. Parker’s research examines the vibration and stability of high-speed mechanical systems. His focus for the last 20 years has been gear vibration with special interest in planetary gears. He has consulted for several companies internationally where analyses based on his research have solved vibration problems in the automotive, helicopter, wind turbine, and aircraft engine industries.

Prof. Parker is a Fellow of the American Society of Mechanical Engineers (ASME) and the American Association for the Advancement of Science. He received the 2015 ASME N. O. Myklestad Award for “major innovation in vibration research and engineering.” The Chinese government selected him as an inaugural awardee for its 1000 Person Plan (千人计划). He has received the US Presidential Early Career Award for Scientists and Engineers (“…the highest honor awarded by the US government to scientists and engineers early in their independent research careers”), the National Science Foundation CAREER, and the US Army Young Investigator Awards, as well as the ASME Gustus Larson Award, Ford Chief Engineer Award, French government Poste Rouge Award, SAE Ralph Teetor Educational Award, ASEE’s Global Engineering Educator and Outstanding Faculty Awards, and five separate research awards from Ohio State University.

He serves on the Editorial Board of the Journal of Sound and Vibration and Mechanism and Machine Theory, and served seven years as Associate Editor for the ASME Journal of Vibration and Acoustics.

Prof. Parker has been a Visiting Fellow at Risoe National Lab (Denmark), the University of New South Wales, the University of Sydney, Tokyo University, NASA Glenn Research Center, and INSA Lyon.