Dirk Engel

From 1999-2001 Engel undertook vocational training as a truck mechanic, prior to studying automotive engineering at the University of Applied Sciences (HAW), Hamburg. From 2005-2008 he was a research associate at the Institute of Automotive and Powertrain Engineering (IFAS), Helmut-Schmidt-University/University of Federal Armed Forces, Hamburg. In 2008 he started work at Volkswagen AG, Wolfsburg, in the CAE methods department, before moving to the chassis pre-development department. Since 2016 he has been a full professor at the University of Applied Sciences (HAW), Hamburg, in the automotive and aerospace engineering department.

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Presentation

Analysis of self-excited vibrations by combining simulation and testing

The non-linear tire slip response, characterized by a peak friction and subsequent decay, makes the wheel system, in specific operating conditions, a marginally stable system: self-excited vibrations are produced. Typical examples are longitudinal vibrations of the powertrain (sometimes also referred to as power-hop) and lateral vibrations of the tire in extreme understeer or oversteer situations. To study this phenomenon, different measuring and modeling methodologies have been recently developed. This presentation reviews these methodologies and demonstrates how testing and modeling can leverage each other to produce a consistent framework to approach the self-excited vibration problem.