#+TITLE: Modal Analysis of the ID31 Micro-Station :DRAWER: #+STARTUP: overview #+LANGUAGE: en #+EMAIL: dehaeze.thomas@gmail.com #+AUTHOR: Dehaeze Thomas #+HTML_LINK_HOME: ../index.html #+HTML_LINK_UP: ../index.html #+HTML_HEAD: #+HTML_HEAD: #+HTML_HEAD: #+HTML_HEAD: #+HTML_HEAD: #+HTML_HEAD: #+HTML_HEAD: #+HTML_MATHJAX: align: center tagside: right font: TeX :END: 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 #+attr_html: :width 500px [[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 #+attr_html: :width 400px [[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: - [[file:measurement.org][Frequency Response Measurements]] - [[file:frf_processing.org][Frequency Response Analysis and Processing]] - [[file:modal_extraction.org][Modal Parameter Extraction]] - [[file:mathematical_model.org][Derivation of Mathematical Model]]