Operational Modal Analysis in the InnoMill project

PhD defence, Wednesday 4 July 2018. Martin Ø. Ø. Juul.

2018.07.04 | Maia Høyer Monod

Martin Ø. Ø. Juul

During his studies, Martin researched applications of Operational Modal Analysis (OMA) in the InnoMill project (supported by the Innovation Fund Denmark under contract number 54-2014-3). The InnoMill project aims at building a small large-scale machining cell for the wind turbine industry. When machining large cast iron structures, vibrations play a significant role for the machining process. The ability to track the dynamics of the machined work piece will make predictions about stability conditions of the machining process possible. To meet this goal, Martin has studied the automation of OMA (AOMA) to enable fast, reliable and potentially continuous parameter estimation. Automated updating of Finite Element (FE) models have also been studied.

The thesis presents several completely novel algorithms for approaching the AOMA problem, a new algorithm for dealing with a phenomenon known as “closely spaced modes”, and a perturbation method for automatic FE model update. A new algorithm for predicting machining instability in a turning process, known as chatter, is also presented.

The PhD degree was completed at the Department of Engineering (ENG), Science and Technology, Aarhus University.

This résumé was prepared by the PhD student.


Time: Wednesday 4 July 2018 at 13.00
Place: Building 3210, room 04.047, Navitas, Aarhus University, Inge Lehmanns Gade 10, 8000 Aarhus C
Title of PhD thesis: Operational Modal Analysis in the InnoMill project
Contact information: Martin Ø. Ø. Juul, e-mail: rimfaxe@gmail.com, tel.: +45 4081 0870
Members of the assessment committee:
Associate Professor Giuliano Coppotelli, Department of Mechanical and Aerospace Engineering, University of Roma Sapienza, Italy
Professor Ilmar Santos, Department of Mechanical Engineering, Technical University of Denmark
Professor Martin Greiner, Department of Engineering, Aarhus University
Main supervisor:
Professor (Docent) Ole Balling, Department of Engineering, Aarhus University
Co-supervisor:
Professor Rune Brincker, Department of Civil Engineering, Technical University of Denmark
Language: The PhD dissertation will be defended in English


The defence is public.

The PhD thesis is available for reading at the Graduate School of Science and Technology/GSST, Ny Munkegade 120, building 1520, rooms 128-134, 8000 Aarhus C.

PhD defence
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Revised 29.06.2018