#+TITLE: Identification :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 #+PROPERTY: header-args:matlab :session *MATLAB* #+PROPERTY: header-args:matlab+ :comments org #+PROPERTY: header-args:matlab+ :results none #+PROPERTY: header-args:matlab+ :exports both #+PROPERTY: header-args:matlab+ :eval no-export #+PROPERTY: header-args:matlab+ :output-dir figs #+PROPERTY: header-args:matlab+ :tangle matlab/modal_frf_coh.m #+PROPERTY: header-args:matlab+ :mkdirp yes #+PROPERTY: header-args:shell :eval no-export #+PROPERTY: header-args:latex :headers '("\\usepackage{tikz}" "\\usepackage{import}" "\\import{$HOME/Cloud/thesis/latex/}{config.tex}") #+PROPERTY: header-args:latex+ :imagemagick t :fit yes #+PROPERTY: header-args:latex+ :iminoptions -scale 100% -density 150 #+PROPERTY: header-args:latex+ :imoutoptions -quality 100 #+PROPERTY: header-args:latex+ :results raw replace :buffer no #+PROPERTY: header-args:latex+ :eval no-export #+PROPERTY: header-args:latex+ :exports both #+PROPERTY: header-args:latex+ :mkdirp yes #+PROPERTY: header-args:latex+ :output-dir figs :END: * Introduction :ignore: The goal here is to make an identification of the *micro-station* in order to compare the model with the measurements on the real micro-station. In order to do so: - Decide where to virtually excite the station and where to measure its motion - Extract transfer functions from the excitation forces to the measured motion - Compare those transfer functions with the modal analysis For the excitation, we can choose the same excitation points as the one used for the modal test. For the measurement points, we can choose the Center of Mass of each solid body. The center of mass of each solid body is not easily defined using Simscape. Indeed, we can define the center of mass of any solid body but not of multiple solid bodies. However, one solid body is composed of multiple STEP files. One solution could be to use one STEP file for one solid body. However, the position of the center of mass can be exported using simulink and then defined on Simscape. * Identification of the Micro-Station ** Introduction :ignore: ** Matlab Init :noexport:ignore: #+begin_src matlab :tangle no :exports none :results silent :noweb yes :var current_dir=(file-name-directory buffer-file-name) <> #+end_src #+begin_src matlab :exports none :results silent :noweb yes <> #+end_src #+begin_src matlab :tangle no simulinkproject('../'); #+end_src ** Compute the transfer functions We first define some parameters for the identification. The simulink file for the identification is =sim_micro_station_id.slx=. #+begin_src matlab open 'simscape/sim_micro_station_id.slx' #+end_src #+begin_src matlab %% Options for Linearized options = linearizeOptions; options.SampleTime = 0; %% Name of the Simulink File mdl = 'sim_micro_station_id'; #+end_src #+begin_src matlab %% Micro-Hexapod % Input/Output definition io(1) = linio([mdl, '/Micro-Station/Fm_ext'],1,'openinput'); io(2) = linio([mdl, '/Micro-Station/Fg_ext'],1,'openinput'); io(3) = linio([mdl, '/Micro-Station/Dm_inertial'],1,'output'); io(4) = linio([mdl, '/Micro-Station/Ty_inertial'],1,'output'); io(5) = linio([mdl, '/Micro-Station/Ry_inertial'],1,'output'); io(6) = linio([mdl, '/Micro-Station/Dg_inertial'],1,'output'); #+end_src #+begin_src matlab % Run the linearization G_ms = linearize(mdl, io, 0); % Input/Output names G_ms.InputName = {'Fmx', 'Fmy', 'Fmz',... 'Fgx', 'Fgy', 'Fgz'}; G_ms.OutputName = {'Dmx', 'Dmy', 'Dmz', ... 'Tyx', 'Tyy', 'Tyz', ... 'Ryx', 'Ryy', 'Ryz', ... 'Dgx', 'Dgy', 'Dgz'}; #+end_src #+begin_src matlab %% Save the obtained transfer functions save('./mat/id_micro_station.mat', 'G_ms'); #+end_src ** Plots the transfer functions ** Compare with the measurements * Modal Analysis of the Micro-Station ** Matlab Init :noexport:ignore: #+begin_src matlab :tangle no :exports none :results silent :noweb yes :var current_dir=(file-name-directory buffer-file-name) <> #+end_src #+begin_src matlab :exports none :results silent :noweb yes <> #+end_src #+begin_src matlab :tangle no simulinkproject('../'); #+end_src ** Simscape Model #+begin_src matlab open 'simscape/sim_micro_station_modal_analysis.slx' #+end_src #+begin_src matlab %% Options for Linearized options = linearizeOptions; options.SampleTime = 0; %% Name of the Simulink File mdl = 'sim_micro_station_modal_analysis'; #+end_src #+begin_src matlab %% Micro-Hexapod % Input/Output definition io(1) = linio([mdl, '/Micro-Station/F_hammer'],1,'openinput'); io(2) = linio([mdl, '/Micro-Station/acc9'],1,'output'); io(3) = linio([mdl, '/Micro-Station/acc10'],1,'output'); io(4) = linio([mdl, '/Micro-Station/acc11'],1,'output'); io(5) = linio([mdl, '/Micro-Station/acc12'],1,'output'); #+end_src #+begin_src matlab % Run the linearization G_ms = linearize(mdl, io, 0); % Input/Output names G_ms.InputName = {'Fx', 'Fy', 'Fz'}; G_ms.OutputName = {'x9', 'y9', 'z9', ... 'x10', 'y10', 'z10', ... 'x11', 'y11', 'z11', ... 'x12', 'y12', 'z12'}; #+end_src ** Plot Results #+begin_src matlab figure; hold on; plot(freqs, abs(squeeze(freqresp(G_ms('x9', 'Fx'), freqs, 'Hz')))); set(gca, 'XScale', 'log'); set(gca, 'YScale', 'log'); ylabel('Amplitude [m/N]'); hold off; #+end_src ** Compare with measurements #+begin_src matlab load('../meas/modal-analysis/mat/frf_coh_matrices.mat', 'FRFs', 'COHs', 'freqs'); #+end_src #+begin_src matlab dirs = {'x', 'y', 'z'}; n_acc = 9; n_dir = 1; % x, y, z n_exc = 1; % x, y, z figure; hold on; plot(freqs, abs(squeeze(FRFs(3*(n_acc-1) + n_dir, n_exc, :)))./((2*pi*freqs).^2)'); plot(freqs, abs(squeeze(freqresp(G_ms([dirs{n_dir}, num2str(n_acc)], ['F', dirs{n_dir}]), freqs, 'Hz')))); set(gca, 'XScale', 'log'); set(gca, 'YScale', 'log'); ylabel('Amplitude [m/N]'); hold off; #+end_src * Compare with measurements at the CoM of each element ** Matlab Init :noexport:ignore: #+begin_src matlab :tangle no :exports none :results silent :noweb yes :var current_dir=(file-name-directory buffer-file-name) <> #+end_src #+begin_src matlab :exports none :results silent :noweb yes <> #+end_src #+begin_src matlab :tangle no simulinkproject('../'); #+end_src ** Init #+begin_src matlab :results none initializeGround(); initializeGranite(); initializeTy(); initializeRy(); initializeRz(); initializeMicroHexapod(); initializeAxisc(); #+end_src ** Center of Mass of each solid body | | granite bot | granite top | ty | ry | rz | hexa | |--------+-------------+-------------+------+------+------+------| | X [mm] | 45 | 52 | 0 | 0 | 0 | -4 | | Y [mm] | 144 | 258 | 14 | -5 | 0 | 6 | | Z [mm] | -1251 | -778 | -600 | -628 | -580 | -319 | #+begin_src matlab open 'simscape/sim_micro_station_modal_analysis_com.slx' #+end_src ** Simscape Model #+begin_src matlab %% Options for Linearized options = linearizeOptions; options.SampleTime = 0; %% Name of the Simulink File mdl = 'sim_micro_station_modal_analysis_com'; #+end_src #+begin_src matlab %% Micro-Hexapod % Input/Output definition io(1) = linio([mdl, '/Micro-Station/F_hammer'],1,'openinput'); io(2) = linio([mdl, '/Micro-Station/acc_gtop'],1,'output'); io(3) = linio([mdl, '/Micro-Station/acc_ty'],1,'output'); io(4) = linio([mdl, '/Micro-Station/acc_ry'],1,'output'); io(5) = linio([mdl, '/Micro-Station/acc_rz'],1,'output'); io(6) = linio([mdl, '/Micro-Station/acc_hexa'],1,'output'); #+end_src #+begin_src matlab % Run the linearization G_ms = linearize(mdl, io, 0); % Input/Output names G_ms.InputName = {'Fx', 'Fy', 'Fz'}; G_ms.OutputName = {'gtop_x', 'gtop_y', 'gtop_z', 'gtop_rx', 'gtop_ry', 'gtop_rz', ... 'ty_x', 'ty_y', 'ty_z', 'ty_rx', 'ty_ry', 'ty_rz', ... 'ry_x', 'ry_y', 'ry_z', 'ry_rx', 'ry_ry', 'ry_rz', ... 'rz_x', 'rz_y', 'rz_z', 'rz_rx', 'rz_ry', 'rz_rz', ... 'hexa_x', 'hexa_y', 'hexa_z', 'hexa_rx', 'hexa_ry', 'hexa_rz'}; #+end_src ** Compare with measurements #+begin_src matlab load('../meas/modal-analysis/mat/frf_coh_matrices.mat', 'freqs'); load('../meas/modal-analysis/mat/frf_com.mat', 'FRFs_CoM'); #+end_src #+begin_src matlab dirs = {'x', 'y', 'z', 'rx', 'ry', 'rz'}; stages = {'gbot', 'gtop', 'ty', 'ry', 'rz', 'hexa'} n_stg = 2; n_dir = 5; % x, y, z, Rx, Ry, Rz n_exc = 2; % x, y, z f = logspace(0, 3, 1000); figure; hold on; plot(freqs, abs(squeeze(FRFs_CoM(6*(n_stg-1) + n_dir, n_exc, :)))./((2*pi*freqs).^2)'); plot(f, abs(squeeze(freqresp(G_ms([stages{n_stg}, '_', dirs{n_dir}], ['F', dirs{n_exc}]), f, 'Hz')))); set(gca, 'XScale', 'log'); set(gca, 'YScale', 'log'); ylabel('Amplitude [m/N]'); hold off; xlim([1, 200]); #+end_src #+begin_src matlab dirs = {'x', 'y', 'z', 'rx', 'ry', 'rz'}; stages = {'gtop', 'ty', 'ry', 'rz', 'hexa'} f = logspace(1, 3, 1000); figure; for n_stg = 1:2 for n_dir = 1:3 subplot(3, 2, (n_dir-1)*2 + n_stg); title(['F ', dirs{n_dir}, ' to ', stages{n_stg}, ' ', dirs{n_dir}]); hold on; plot(freqs, abs(squeeze(FRFs_CoM(6*(n_stg) + n_dir, n_dir, :)))./((2*pi*freqs).^2)'); plot(f, abs(squeeze(freqresp(G_ms([stages{n_stg}, '_', dirs{n_dir}], ['F', dirs{n_dir}]), f, 'Hz')))); set(gca, 'XScale', 'log'); set(gca, 'YScale', 'log'); ylabel('Amplitude [m/N]'); if n_dir == 3 xlabel('Frequency [Hz]'); end hold off; xlim([10, 1000]); ylim([1e-12, 1e-6]); end end #+end_src #+HEADER: :tangle no :exports results :results none :noweb yes #+begin_src matlab :var filepath="figs/identification_comp_bot_stages.pdf" :var figsize="full-tall" :post pdf2svg(file=*this*, ext="png") <> #+end_src #+NAME: fig:identification_comp_bot_stages #+CAPTION: caption ([[./figs/identification_comp_bot_stages.png][png]], [[./figs/identification_comp_bot_stages.pdf][pdf]]) [[file:figs/identification_comp_bot_stages.png]] #+begin_src matlab dirs = {'x', 'y', 'z', 'rx', 'ry', 'rz'}; stages = {'ry', 'rz', 'hexa'} f = logspace(1, 3, 1000); figure; for n_stg = 1:2 for n_dir = 1:3 subplot(3, 2, (n_dir-1)*2 + n_stg); title(['F ', dirs{n_dir}, ' to ', stages{n_stg}, ' ', dirs{n_dir}]); hold on; plot(freqs, abs(squeeze(FRFs_CoM(6*(n_stg+2) + n_dir, n_dir, :)))./((2*pi*freqs).^2)'); plot(f, abs(squeeze(freqresp(G_ms([stages{n_stg}, '_', dirs{n_dir}], ['F', dirs{n_dir}]), f, 'Hz')))); set(gca, 'XScale', 'log'); set(gca, 'YScale', 'log'); ylabel('Amplitude [m/N]'); if n_dir == 3 xlabel('Frequency [Hz]'); end hold off; xlim([10, 1000]); ylim([1e-12, 1e-6]); end end #+end_src #+HEADER: :tangle no :exports results :results none :noweb yes #+begin_src matlab :var filepath="figs/identification_comp_mid_stages.pdf" :var figsize="full-tall" :post pdf2svg(file=*this*, ext="png") <> #+end_src #+NAME: fig:identification_comp_mid_stages #+CAPTION: caption ([[./figs/identification_comp_mid_stages.png][png]], [[./figs/identification_comp_mid_stages.pdf][pdf]]) [[file:figs/identification_comp_mid_stages.png]] #+begin_src matlab dirs = {'x', 'y', 'z', 'rx', 'ry', 'rz'}; stages = {'hexa'} f = logspace(1, 3, 1000); figure; for n_stg = 1 for n_dir = 1:3 subplot(3, 1, (n_dir-1)*2 + n_stg); title(['F ', dirs{n_dir}, ' to ', stages{n_stg}, ' ', dirs{n_dir}]); hold on; plot(freqs, abs(squeeze(FRFs_CoM(6*(n_stg+4) + n_dir, n_dir, :)))./((2*pi*freqs).^2)'); plot(f, abs(squeeze(freqresp(G_ms([stages{n_stg}, '_', dirs{n_dir}], ['F', dirs{n_dir}]), f, 'Hz')))); set(gca, 'XScale', 'log'); set(gca, 'YScale', 'log'); ylabel('Amplitude [m/N]'); if n_dir == 3 xlabel('Frequency [Hz]'); end hold off; xlim([10, 1000]); ylim([1e-12, 1e-6]); end end #+end_src #+HEADER: :tangle no :exports results :results none :noweb yes #+begin_src matlab :var filepath="figs/identification_comp_top_stages.pdf" :var figsize="full-tall" :post pdf2svg(file=*this*, ext="png") <> #+end_src #+NAME: fig:identification_comp_top_stages #+CAPTION: caption ([[./figs/identification_comp_top_stages.png][png]], [[./figs/identification_comp_top_stages.pdf][pdf]]) [[file:figs/identification_comp_top_stages.png]] * ZIP file containing the data and matlab files :ignore: #+begin_src bash :exports none :results none if [ matlab/identification_micro_station.m -nt data/identification_micro_station.zip ]; then cp matlab/identification_micro_station.m identification_micro_station.m; zip data/identification_micro_station \ mat/data.mat \ identification_micro_station.m rm identification_micro_station.m; fi #+end_src #+begin_note All the files (data and Matlab scripts) are accessible [[file:data/identification_micro_station.zip][here]]. #+end_note * Matlab Init :noexport:ignore: #+begin_src matlab :tangle no :exports none :results silent :noweb yes :var current_dir=(file-name-directory buffer-file-name) <> #+end_src #+begin_src matlab :exports none :results silent :noweb yes <> #+end_src * Identification of the micro-station #+begin_src matlab simulinkproject('../'); #+end_src #+begin_src matlab open sim_micro_station_id.slx #+end_src * Plot the obtained transfer functions * Compare with the modal measurements * Modal Identification of the micro station