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Experimental conditions</a></li> <li><a href="#orgf2bb684">2. Measurements procedure</a></li> <li><a href="#org604de72">3. Measurement Channels</a></li> <li><a href="#orgee6f009">4. Experiments</a></li> <li><a href="#orgc91528e">5. Data Analysis</a> <ul> <li><a href="#org64c9d55">5.1. Loading and pre-processing of the data</a></li> <li><a href="#org528d8bd">5.2. X-direction FRF</a></li> <li><a href="#orgb043f14">5.3. Y-direction FRF</a></li> <li><a href="#org63f36f4">5.4. Z-direction FRF</a></li> <li><a href="#org9fd4cff">5.5. Save the processed data</a></li> </ul> </li> <li><a href="#orge5ef1a0">6. Results</a></li> </ul> </div> </div> <div id="outline-container-org27cbd90" class="outline-2"> <h2 id="org27cbd90"><span class="section-number-2">1</span> Experimental conditions</h2> <div class="outline-text-2" id="text-1"> <table border="2" cellspacing="0" cellpadding="6" rules="groups" frame="hsides"> <colgroup> <col class="org-left" /> <col class="org-left" /> </colgroup> <tbody> <tr> <td class="org-left"><b>Date</b></td> <td class="org-left">2018-01-12</td> </tr> <tr> <td class="org-left"><b>Sensors</b></td> <td class="org-left">Geophones</td> </tr> <tr> <td class="org-left"><b>Excitation</b></td> <td class="org-left">Instrumented Hammer</td> </tr> <tr> <td class="org-left"><b>Location</b></td> <td class="org-left">Laboratory</td> </tr> <tr> <td class="org-left"><b>Notes</b></td> <td class="org-left">Unglued Granite</td> </tr> </tbody> </table> <ul class="org-ul"> <li>The granite is not glued to the floor</li> <li>FS = 512Hz</li> <li>Made by Marc Lesourd on the 12 of January 2018</li> </ul> <p> <b>Goal</b>: Obtain better coherence at low frequency. </p> </div> </div> <div id="outline-container-orgf2bb684" class="outline-2"> <h2 id="orgf2bb684"><span class="section-number-2">2</span> Measurements procedure</h2> <div class="outline-text-2" id="text-2"> <p> <b>Geophones</b> L-28LB geophones (table <a href="#org27c9f01">1</a>) are placed on </p> <ul class="org-ul"> <li>Marle</li> <li>Tilt Stage</li> <li>Top of Hexapod</li> </ul> <table id="org27c9f01" border="2" cellspacing="0" cellpadding="6" rules="groups" frame="hsides"> <caption class="t-above"><span class="table-number">Table 1:</span> L-28LB Geophone characteristics</caption> <colgroup> <col class="org-left" /> <col class="org-right" /> </colgroup> <tbody> <tr> <td class="org-left">Natural Frequency [Hz]</td> <td class="org-right">4.5</td> </tr> <tr> <td class="org-left">Weight [g]</td> <td class="org-right">140</td> </tr> <tr> <td class="org-left">Sensitivity [V/(m/s)]</td> <td class="org-right">31.3</td> </tr> </tbody> </table> <p> The structure is excited using an <b>instrumented hammer</b> with impacts on </p> <ul class="org-ul"> <li>Marble X-Y-Z</li> <li>Hexapod X-Y-Z</li> </ul> </div> </div> <div id="outline-container-org604de72" class="outline-2"> <h2 id="org604de72"><span class="section-number-2">3</span> Measurement Channels</h2> <div class="outline-text-2" id="text-3"> <table id="org98c14df" border="2" cellspacing="0" cellpadding="6" rules="groups" frame="hsides"> <caption class="t-above"><span class="table-number">Table 2:</span> Description of each measurement channel</caption> <colgroup> <col class="org-right" /> <col class="org-left" /> <col class="org-left" /> <col class="org-left" /> </colgroup> <thead> <tr> <th scope="col" class="org-right">Ch. nb</th> <th scope="col" class="org-left">Element</th> <th scope="col" class="org-left">Location</th> <th scope="col" class="org-left">Direction</th> </tr> </thead> <tbody> <tr> <td class="org-right">1</td> <td class="org-left">Hammer</td> <td class="org-left">variable</td> <td class="org-left"> </td> </tr> </tbody> <tbody> <tr> <td class="org-right">2</td> <td class="org-left">Geophone</td> <td class="org-left">Marble</td> <td class="org-left">X-Y-Z</td> </tr> <tr> <td class="org-right">3</td> <td class="org-left">Geophone</td> <td class="org-left">Tilt stage</td> <td class="org-left">X-Y-Z</td> </tr> <tr> <td class="org-right">4</td> <td class="org-left">Geophone</td> <td class="org-left">Top of Hexapod</td> <td class="org-left">X-Y-Z</td> </tr> </tbody> </table> </div> </div> <div id="outline-container-orgee6f009" class="outline-2"> <h2 id="orgee6f009"><span class="section-number-2">4</span> Experiments</h2> <div class="outline-text-2" id="text-4"> <table id="orgd57c63a" border="2" cellspacing="0" cellpadding="6" rules="groups" frame="hsides"> <caption class="t-above"><span class="table-number">Table 3:</span> Description of the location of direction of the excitation for each measurement</caption> <colgroup> <col class="org-right" /> <col class="org-left" /> <col class="org-left" /> </colgroup> <thead> <tr> <th scope="col" class="org-right">Meas. nb</th> <th scope="col" class="org-left">Location</th> <th scope="col" class="org-left">Direction</th> </tr> </thead> <tbody> <tr> <td class="org-right">1</td> <td class="org-left">Marble</td> <td class="org-left">X</td> </tr> <tr> <td class="org-right">2</td> <td class="org-left">Hexapod</td> <td class="org-left">X</td> </tr> </tbody> <tbody> <tr> <td class="org-right">3</td> <td class="org-left">Marble</td> <td class="org-left">Y</td> </tr> <tr> <td class="org-right">4</td> <td class="org-left">Hexapod</td> <td class="org-left">Y</td> </tr> </tbody> <tbody> <tr> <td class="org-right">5</td> <td class="org-left">Marble</td> <td class="org-left">Z</td> </tr> <tr> <td class="org-right">6</td> <td class="org-left">Hexapod</td> <td class="org-left">Z</td> </tr> </tbody> </table> </div> </div> <div id="outline-container-orgc91528e" class="outline-2"> <h2 id="orgc91528e"><span class="section-number-2">5</span> Data Analysis</h2> <div class="outline-text-2" id="text-5"> </div> <div id="outline-container-org64c9d55" class="outline-3"> <h3 id="org64c9d55"><span class="section-number-3">5.1</span> Loading and pre-processing of the data</h3> <div class="outline-text-3" id="text-5-1"> <p> The Geophone sensitivity is defined below: </p> <div class="org-src-container"> <pre class="src src-matlab">w0 = <span class="org-highlight-numbers-number">4</span>.<span class="org-highlight-numbers-number">5</span><span class="org-type">*</span><span class="org-highlight-numbers-number">2</span><span class="org-type">*</span><span class="org-constant">pi</span>; <span class="org-comment">% [rad/s]</span> ksi = <span class="org-highlight-numbers-number">0</span>.<span class="org-highlight-numbers-number">38</span>; G0 = <span class="org-highlight-numbers-number">31</span>.<span class="org-highlight-numbers-number">3</span>; <span class="org-comment">% [V/(m/s)]</span> G = G0<span class="org-type">*</span><span class="org-rainbow-delimiters-depth-1">(</span>s<span class="org-type">/</span>w0<span class="org-rainbow-delimiters-depth-1">)</span><span class="org-type">^</span><span class="org-highlight-numbers-number">2</span><span class="org-type">/</span><span class="org-rainbow-delimiters-depth-1">(</span><span class="org-rainbow-delimiters-depth-2">(</span>s<span class="org-type">/</span>w0<span class="org-rainbow-delimiters-depth-2">)</span><span class="org-type">^</span><span class="org-highlight-numbers-number">2</span> <span class="org-type">+</span> <span class="org-highlight-numbers-number">2</span><span class="org-type">*</span>ksi<span class="org-type">*</span><span class="org-rainbow-delimiters-depth-2">(</span>s<span class="org-type">/</span>w0<span class="org-rainbow-delimiters-depth-2">)</span> <span class="org-type">+</span> <span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-1">)</span>; <span class="org-comment">% [V/(m/s)]</span> </pre> </div> <p> We then: </p> <ul class="org-ul"> <li>load the data</li> <li>add a minus sign when needed</li> <li>integrate the signal to have displacement instead of velocity</li> <li>scaled with the sensitivity of the Geophone</li> </ul> <div class="org-src-container"> <pre class="src src-matlab">load<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'./raw_data/freq_frf.mat'</span><span class="org-rainbow-delimiters-depth-1">)</span> <span class="org-comment">% freq_frf</span> w = <span class="org-constant">j</span><span class="org-type">*</span><span class="org-highlight-numbers-number">2</span><span class="org-type">*</span><span class="org-constant">pi</span><span class="org-type">*</span>freq_frf; <span class="org-comment">% j.omega in [rad/s]</span> scaling = squeeze<span class="org-rainbow-delimiters-depth-1">(</span>freqresp<span class="org-rainbow-delimiters-depth-2">(</span>G, <span class="org-highlight-numbers-number">2</span><span class="org-type">*</span><span class="org-constant">pi</span><span class="org-type">*</span>freq_frf<span class="org-rainbow-delimiters-depth-2">)</span><span class="org-rainbow-delimiters-depth-1">)</span><span class="org-type">/</span>G0; load<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'./raw_data/frf_marble_x.mat'</span><span class="org-rainbow-delimiters-depth-1">)</span> <span class="org-comment">% ReIm1</span> frf_marble_x = zeros<span class="org-rainbow-delimiters-depth-1">(</span>size<span class="org-rainbow-delimiters-depth-2">(</span>ReIm1, <span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-2">)</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span>; frf_marble_x<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-1">)</span> = <span class="org-type">-</span>ReIm1<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-1">)</span><span class="org-type">./</span>w<span class="org-type">./</span>scaling; <span class="org-comment">% marble_x</span> frf_marble_x<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-1">)</span> = <span class="org-type">-</span>ReIm1<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span><span class="org-type">./</span>w<span class="org-type">./</span>scaling; <span class="org-comment">% tilt_x</span> frf_marble_x<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span> = <span class="org-type">-</span>ReIm1<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">4</span><span class="org-rainbow-delimiters-depth-1">)</span><span class="org-type">./</span>w<span class="org-type">./</span>scaling; <span class="org-comment">% hexa_x</span> load<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'./raw_data/frf_hexa_x.mat'</span><span class="org-rainbow-delimiters-depth-1">)</span> <span class="org-comment">% ReIm2</span> frf_hexa_x = zeros<span class="org-rainbow-delimiters-depth-1">(</span>size<span class="org-rainbow-delimiters-depth-2">(</span>ReIm2, <span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-2">)</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span>; frf_hexa_x<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-1">)</span> = <span class="org-type">-</span>ReIm2<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-1">)</span><span class="org-type">./</span>w<span class="org-type">./</span>scaling; <span class="org-comment">% marble_x</span> frf_hexa_x<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-1">)</span> = <span class="org-type">-</span>ReIm2<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span><span class="org-type">./</span>w<span class="org-type">./</span>scaling; <span class="org-comment">% tilt_x</span> frf_hexa_x<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span> = <span class="org-type">-</span>ReIm2<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">4</span><span class="org-rainbow-delimiters-depth-1">)</span><span class="org-type">./</span>w<span class="org-type">./</span>scaling; <span class="org-comment">% hexa_x</span> load<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'./raw_data/frf_marble_y.mat'</span><span class="org-rainbow-delimiters-depth-1">)</span> <span class="org-comment">% ReIm3</span> frf_marble_y = zeros<span class="org-rainbow-delimiters-depth-1">(</span>size<span class="org-rainbow-delimiters-depth-2">(</span>ReIm3, <span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-2">)</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span>; frf_marble_y<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-1">)</span> = <span class="org-type">-</span>ReIm3<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-1">)</span><span class="org-type">./</span>w<span class="org-type">./</span>scaling; <span class="org-comment">% marble_y</span> frf_marble_y<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-1">)</span> = <span class="org-type">-</span>ReIm3<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span><span class="org-type">./</span>w<span class="org-type">./</span>scaling; <span class="org-comment">% tilt_y</span> frf_marble_y<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span> = <span class="org-type">-</span>ReIm3<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">4</span><span class="org-rainbow-delimiters-depth-1">)</span><span class="org-type">./</span>w<span class="org-type">./</span>scaling; <span class="org-comment">% hexa_y</span> load<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'./raw_data/frf_hexa_y.mat'</span><span class="org-rainbow-delimiters-depth-1">)</span> <span class="org-comment">% ReIm4</span> frf_hexa_y = zeros<span class="org-rainbow-delimiters-depth-1">(</span>size<span class="org-rainbow-delimiters-depth-2">(</span>ReIm4, <span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-2">)</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span>; frf_hexa_y<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-1">)</span> = ReIm4<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-1">)</span><span class="org-type">./</span>w<span class="org-type">./</span>scaling; <span class="org-comment">% marble_y</span> frf_hexa_y<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-1">)</span> = ReIm4<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span><span class="org-type">./</span>w<span class="org-type">./</span>scaling; <span class="org-comment">% tilt_y</span> frf_hexa_y<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span> = ReIm4<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">4</span><span class="org-rainbow-delimiters-depth-1">)</span><span class="org-type">./</span>w<span class="org-type">./</span>scaling; <span class="org-comment">% hexa_y</span> load<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'./raw_data/frf_marble_z.mat'</span><span class="org-rainbow-delimiters-depth-1">)</span> <span class="org-comment">% ReIm5</span> frf_marble_z = zeros<span class="org-rainbow-delimiters-depth-1">(</span>size<span class="org-rainbow-delimiters-depth-2">(</span>ReIm5, <span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-2">)</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span>; frf_marble_z<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-1">)</span> = ReIm5<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-1">)</span><span class="org-type">./</span>w<span class="org-type">./</span>scaling; <span class="org-comment">% marble_z</span> frf_marble_z<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-1">)</span> = ReIm5<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span><span class="org-type">./</span>w<span class="org-type">./</span>scaling; <span class="org-comment">% tilt_z</span> frf_marble_z<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span> = ReIm5<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">4</span><span class="org-rainbow-delimiters-depth-1">)</span><span class="org-type">./</span>w<span class="org-type">./</span>scaling; <span class="org-comment">% hexa_z</span> load<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'./raw_data/frf_hexa_z.mat'</span><span class="org-rainbow-delimiters-depth-1">)</span> <span class="org-comment">% ReIm6</span> frf_hexa_z = zeros<span class="org-rainbow-delimiters-depth-1">(</span>size<span class="org-rainbow-delimiters-depth-2">(</span>ReIm6, <span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-2">)</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span>; frf_hexa_z<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-1">)</span> = ReIm6<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-1">)</span><span class="org-type">./</span>w<span class="org-type">./</span>scaling; <span class="org-comment">% marble_z</span> frf_hexa_z<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-1">)</span> = ReIm6<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span><span class="org-type">./</span>w<span class="org-type">./</span>scaling; <span class="org-comment">% tilt_z</span> frf_hexa_z<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span> = ReIm6<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">4</span><span class="org-rainbow-delimiters-depth-1">)</span><span class="org-type">./</span>w<span class="org-type">./</span>scaling; <span class="org-comment">% hexa_z</span> </pre> </div> <div class="org-src-container"> <pre class="src src-matlab">load<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'./raw_data/coher_marble_x.mat'</span><span class="org-rainbow-delimiters-depth-1">)</span> <span class="org-comment">% coh1</span> coh_marble_x = zeros<span class="org-rainbow-delimiters-depth-1">(</span>size<span class="org-rainbow-delimiters-depth-2">(</span>coh1, <span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-2">)</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span>; coh_marble_x<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-1">)</span> = coh1<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-1">)</span>; <span class="org-comment">% marble_x</span> coh_marble_x<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-1">)</span> = coh1<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span>; <span class="org-comment">% tilt_x</span> coh_marble_x<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span> = coh1<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">4</span><span class="org-rainbow-delimiters-depth-1">)</span>; <span class="org-comment">% hexa_x</span> load<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'./raw_data/coher_hexa_x.mat'</span><span class="org-rainbow-delimiters-depth-1">)</span> <span class="org-comment">% coh2</span> coh_hexa_x = zeros<span class="org-rainbow-delimiters-depth-1">(</span>size<span class="org-rainbow-delimiters-depth-2">(</span>coh2, <span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-2">)</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span>; coh_hexa_x<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-1">)</span> = coh2<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-1">)</span>; <span class="org-comment">% marble_x</span> coh_hexa_x<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-1">)</span> = coh2<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span>; <span class="org-comment">% tilt_x</span> coh_hexa_x<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span> = coh2<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">4</span><span class="org-rainbow-delimiters-depth-1">)</span>; <span class="org-comment">% hexa_x</span> load<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'./raw_data/coher_marble_y.mat'</span><span class="org-rainbow-delimiters-depth-1">)</span> <span class="org-comment">% coh3</span> coh_marble_y = zeros<span class="org-rainbow-delimiters-depth-1">(</span>size<span class="org-rainbow-delimiters-depth-2">(</span>coh3, <span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-2">)</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span>; coh_marble_y<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-1">)</span> = coh3<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-1">)</span>; <span class="org-comment">% marble_y</span> coh_marble_y<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-1">)</span> = coh3<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span>; <span class="org-comment">% tilt_y</span> coh_marble_y<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span> = coh3<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">4</span><span class="org-rainbow-delimiters-depth-1">)</span>; <span class="org-comment">% hexa_y</span> load<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'./raw_data/coher_hexa_y.mat'</span><span class="org-rainbow-delimiters-depth-1">)</span> <span class="org-comment">% coh4</span> coh_hexa_y = zeros<span class="org-rainbow-delimiters-depth-1">(</span>size<span class="org-rainbow-delimiters-depth-2">(</span>coh4, <span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-2">)</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span>; coh_hexa_y<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-1">)</span> = coh4<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-1">)</span>; <span class="org-comment">% marble_y</span> coh_hexa_y<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-1">)</span> = coh4<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span>; <span class="org-comment">% tilt_y</span> coh_hexa_y<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span> = coh4<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">4</span><span class="org-rainbow-delimiters-depth-1">)</span>; <span class="org-comment">% hexa_y</span> load<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'./raw_data/coher_marble_z.mat'</span><span class="org-rainbow-delimiters-depth-1">)</span> <span class="org-comment">% coh5</span> coh_marble_z = zeros<span class="org-rainbow-delimiters-depth-1">(</span>size<span class="org-rainbow-delimiters-depth-2">(</span>coh5, <span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-2">)</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span>; coh_marble_z<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-1">)</span> = coh5<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-1">)</span>; <span class="org-comment">% marble_z</span> coh_marble_z<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-1">)</span> = coh5<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span>; <span class="org-comment">% tilt_z</span> coh_marble_z<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span> = coh5<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">4</span><span class="org-rainbow-delimiters-depth-1">)</span>; <span class="org-comment">% hexa_z</span> load<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'./raw_data/coher_hexa_z.mat'</span><span class="org-rainbow-delimiters-depth-1">)</span> <span class="org-comment">% coh6</span> coh_hexa_z = zeros<span class="org-rainbow-delimiters-depth-1">(</span>size<span class="org-rainbow-delimiters-depth-2">(</span>coh6, <span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-2">)</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span>; coh_hexa_z<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-1">)</span> = coh6<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-1">)</span>; <span class="org-comment">% marble_z</span> coh_hexa_z<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-1">)</span> = coh6<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span>; <span class="org-comment">% tilt_z</span> coh_hexa_z<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span> = coh6<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">4</span><span class="org-rainbow-delimiters-depth-1">)</span>; <span class="org-comment">% hexa_z</span> </pre> </div> </div> </div> <div id="outline-container-org528d8bd" class="outline-3"> <h3 id="org528d8bd"><span class="section-number-3">5.2</span> X-direction FRF</h3> <div class="outline-text-3" id="text-5-2"> <div id="orgbe46711" class="figure"> <p><img src="figs/marble_x_frf.png" alt="marble_x_frf.png" /> </p> <p><span class="figure-number">Figure 1: </span>Response to a force applied on the marble in the X direction</p> </div> <div id="org4005c39" class="figure"> <p><img src="figs/hexa_x_frf.png" alt="hexa_x_frf.png" /> </p> <p><span class="figure-number">Figure 2: </span>Response to a force applied on the hexa in the X direction</p> </div> </div> </div> <div id="outline-container-orgb043f14" class="outline-3"> <h3 id="orgb043f14"><span class="section-number-3">5.3</span> Y-direction FRF</h3> <div class="outline-text-3" id="text-5-3"> <div id="org959d073" class="figure"> <p><img src="figs/marble_y_frf.png" alt="marble_y_frf.png" /> </p> <p><span class="figure-number">Figure 3: </span>Response to a force applied on the marble in the Y direction</p> </div> <div id="orge15a0ff" class="figure"> <p><img src="figs/hexa_y_frf.png" alt="hexa_y_frf.png" /> </p> <p><span class="figure-number">Figure 4: </span>Response to a force applied on the hexa in the Y direction</p> </div> </div> </div> <div id="outline-container-org63f36f4" class="outline-3"> <h3 id="org63f36f4"><span class="section-number-3">5.4</span> Z-direction FRF</h3> <div class="outline-text-3" id="text-5-4"> <div id="orgf2ca329" class="figure"> <p><img src="figs/marble_z_frf.png" alt="marble_z_frf.png" /> </p> <p><span class="figure-number">Figure 5: </span>Response to a force applied on the marble in the Z direction</p> </div> <div id="orgbb33b62" class="figure"> <p><img src="figs/hexa_z_frf.png" alt="hexa_z_frf.png" /> </p> <p><span class="figure-number">Figure 6: </span>Response to a force applied on the hexa in the Z direction</p> </div> </div> </div> <div id="outline-container-org9fd4cff" class="outline-3"> <h3 id="org9fd4cff"><span class="section-number-3">5.5</span> Save the processed data</h3> <div class="outline-text-3" id="text-5-5"> <p> Finally, we save the processed data. </p> <div class="org-src-container"> <pre class="src src-matlab">save<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'./data/id31_microstation_2018_01_12_frf.mat'</span>, <span class="org-underline">...</span> <span class="org-string">'freq_frf'</span>, <span class="org-underline">...</span> <span class="org-string">'frf_marble_x'</span>, <span class="org-underline">...</span> <span class="org-string">'frf_marble_y'</span>, <span class="org-underline">...</span> <span class="org-string">'frf_marble_z'</span>, <span class="org-underline">...</span> <span class="org-string">'frf_hexa_x'</span>, <span class="org-underline">...</span> <span class="org-string">'frf_hexa_y'</span>, <span class="org-underline">...</span> <span class="org-string">'frf_hexa_z'</span><span class="org-rainbow-delimiters-depth-1">)</span>; save<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'./data/id31_microstation_2018_01_12_coh.mat'</span>, <span class="org-underline">...</span> <span class="org-string">'freq_frf'</span>, <span class="org-underline">...</span> <span class="org-string">'coh_marble_x'</span>, <span class="org-underline">...</span> <span class="org-string">'coh_marble_y'</span>, <span class="org-underline">...</span> <span class="org-string">'coh_marble_z'</span>, <span class="org-underline">...</span> <span class="org-string">'coh_hexa_x'</span>, <span class="org-underline">...</span> <span class="org-string">'coh_hexa_y'</span>, <span class="org-underline">...</span> <span class="org-string">'coh_hexa_z'</span><span class="org-rainbow-delimiters-depth-1">)</span>; </pre> </div> </div> </div> </div> <div id="outline-container-orge5ef1a0" class="outline-2"> <h2 id="orge5ef1a0"><span class="section-number-2">6</span> Results</h2> <div class="outline-text-2" id="text-6"> <div class="important"> <ul class="org-ul"> <li>Resonances at 42Hz, 70Hz and 125Hz have been identified</li> <li>The coherence is much better than when using accelerometers</li> </ul> </div> </div> </div> </div> <div id="postamble" class="status"> <p class="author">Author: Dehaeze Thomas</p> <p class="date">Created: 2019-05-14 mar. 23:06</p> <p class="validation"><a href="http://validator.w3.org/check?uri=referer">Validate</a></p> </div> </body> </html>