The goal is to experimentally extract a *Spatial Model* (mass, damping, stiffness) of the structure (shown on figure [[fig:nass_picture]]) in order to tune the Multi-Body model.
#+name: fig:nass_picture
#+caption: Picture of the ID31 Micro-Station. (1) Granite (2) Translation Stage (3) Tilt Stage (4) Hexapod (5) Dummy Mass
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[[file:img/nass_picture.png]]
The procedure is represented on figure [[fig:vibration_analysis_procedure]] where we go from left to right.
#+name: fig:vibration_analysis_procedure
#+caption: Vibration Analysis Procedure
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[[file:img/vibration_analysis_procedure.png]]
The steps are:
- we obtain a *Response Model* (Frequency Response Functions) from measurements (described [[file:measurement.org][here]])
- the response model is further converted into a *Modal Model* (Natural Frequencies and Mode Shapes) (described [[file:modal_extraction.org][here]])
- this is converted into a *Spatial Model* with the Mass/Damping/Stiffness matrices (described [[file:mathematical_model.org][here]])
Theses matrices will be used to tune the Simscape (multi-body) model.
The modes we want to identify are those in the frequency range between 0Hz and 150Hz.
The modal analysis of the ID31 Micro-station thus consists of several parts:
