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As additional permission under GNU GPL version 3 section 7, you may distribute non-source (e.g., minimized or compacted) forms of that code without the copy of the GNU GPL normally required by section 4, provided you include this license notice and a URL through which recipients can access the Corresponding Source. @licend The above is the entire license notice for the JavaScript code in this tag. */ <!--/*--><![CDATA[/*><!--*/ function CodeHighlightOn(elem, id) { var target = document.getElementById(id); if(null != target) { elem.cacheClassElem = elem.className; elem.cacheClassTarget = target.className; target.className = "code-highlighted"; elem.className = "code-highlighted"; } } function CodeHighlightOff(elem, id) { var target = document.getElementById(id); if(elem.cacheClassElem) elem.className = elem.cacheClassElem; if(elem.cacheClassTarget) target.className = elem.cacheClassTarget; } /*]]>*///--> </script> </head> <body> <div id="org-div-home-and-up"> <a accesskey="h" href="../index.html"> UP </a> | <a accesskey="H" href="../index.html"> HOME </a> </div><div id="content"> <h1 class="title">Vibrations induced by the Slip-Ring and the Spindle</h1> <div id="table-of-contents"> <h2>Table of Contents</h2> <div id="text-table-of-contents"> <ul> <li><a href="#org2ead7e9">1. Experimental Setup</a></li> <li><a href="#org8e5682f">2. Data Analysis</a> <ul> <li><a href="#org71d31f6">2.1. Load data</a></li> <li><a href="#org36715e9">2.2. Time domain plots</a></li> <li><a href="#org32ab030">2.3. Compute the power spectral densities</a></li> <li><a href="#orgb8b258a">2.4. Compute the transfer function from floor motion to ground motion</a></li> <li><a href="#org806c2da">2.5. Conclusion</a></li> </ul> </li> </ul> </div> </div> <div id="outline-container-org2ead7e9" class="outline-2"> <h2 id="org2ead7e9"><span class="section-number-2">1</span> Experimental Setup</h2> <div class="outline-text-2" id="text-1"> <p> <b>Setup</b>: One geophone is located on the marble, the other one on the floor (see figure <a href="#org04c2f7b">1</a>). </p> <p> Two geophone are use: </p> <ul class="org-ul"> <li>One on the floor (corresponding to the first column in the data)</li> <li>One at the marble location (corresponding to the second column in the data)</li> </ul> <p> Two voltage amplifiers are used, their setup is: </p> <ul class="org-ul"> <li>gain of 60dB</li> <li>AC/DC switch on AC</li> <li>Low pass filter at 1kHz</li> </ul> <p> A first order low pass filter is also added at the input of the voltage amplifiers. </p> <p> <b>Goal</b>: </p> <ul class="org-ul"> <li>Identify the marble dynamics in all the directions</li> </ul> <p> <b>Measurements</b>: Three measurements are done: </p> <table border="2" cellspacing="0" cellpadding="6" rules="groups" frame="hsides"> <colgroup> <col class="org-left" /> <col class="org-left" /> </colgroup> <thead> <tr> <th scope="col" class="org-left">Measurement File</th> <th scope="col" class="org-left">Description</th> </tr> </thead> <tbody> <tr> <td class="org-left"><code>mat/data_037.mat</code></td> <td class="org-left">Z direction</td> </tr> <tr> <td class="org-left"><code>mat/data_038.mat</code></td> <td class="org-left">N direction</td> </tr> <tr> <td class="org-left"><code>mat/data_039.mat</code></td> <td class="org-left">E direction</td> </tr> </tbody> </table> <p> Each of the measurement <code>mat</code> file contains one <code>data</code> array with 3 columns: </p> <table border="2" cellspacing="0" cellpadding="6" rules="groups" frame="hsides"> <colgroup> <col class="org-right" /> <col class="org-left" /> </colgroup> <thead> <tr> <th scope="col" class="org-right">Column number</th> <th scope="col" class="org-left">Description</th> </tr> </thead> <tbody> <tr> <td class="org-right">1</td> <td class="org-left">Geophone - Floor</td> </tr> <tr> <td class="org-right">2</td> <td class="org-left">Geophone - Marble</td> </tr> <tr> <td class="org-right">3</td> <td class="org-left">Time</td> </tr> </tbody> </table> <div id="org04c2f7b" class="figure"> <p><img src="./img/IMG_20190513_161729.jpg" alt="IMG_20190513_161729.jpg" width="500px" /> </p> <p><span class="figure-number">Figure 1: </span>Picture of the experimental setup</p> </div> <div id="orge39c59f" class="figure"> <p><img src="./img/IMG_20190513_161718.jpg" alt="IMG_20190513_161718.jpg" width="500px" /> </p> <p><span class="figure-number">Figure 2: </span>Picture of the experimental setup</p> </div> </div> </div> <div id="outline-container-org8e5682f" class="outline-2"> <h2 id="org8e5682f"><span class="section-number-2">2</span> Data Analysis</h2> <div class="outline-text-2" id="text-2"> <p> <a id="org4b537af"></a> </p> <div class="note"> <p> All the files (data and Matlab scripts) are accessible <a href="data/marble_dynamics.zip">here</a>. </p> </div> </div> <div id="outline-container-org71d31f6" class="outline-3"> <h3 id="org71d31f6"><span class="section-number-3">2.1</span> Load data</h3> <div class="outline-text-3" id="text-2-1"> <div class="org-src-container"> <pre class="src src-matlab">m_z = load<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'mat/data_037.mat', 'data'</span><span class="org-rainbow-delimiters-depth-1">)</span>; m_z = m_z.data; m_n = load<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'mat/data_038.mat', 'data'</span><span class="org-rainbow-delimiters-depth-1">)</span>; m_n = m_n.data; m_e = load<span class="org-rainbow-delimiters-depth-1">(</span>'mat<span class="org-type">/</span>data_039.mat', <span class="org-string">'data'</span><span class="org-rainbow-delimiters-depth-1">)</span>; m_e = m_e.data; </pre> </div> </div> </div> <div id="outline-container-org36715e9" class="outline-3"> <h3 id="org36715e9"><span class="section-number-3">2.2</span> Time domain plots</h3> <div class="outline-text-3" id="text-2-2"> <div class="org-src-container"> <pre class="src src-matlab"><span class="org-type">figure</span>; subplot<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-highlight-numbers-number">1</span>, <span class="org-highlight-numbers-number">3</span>, <span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-1">)</span>; hold on; plot<span class="org-rainbow-delimiters-depth-1">(</span>m_z<span class="org-rainbow-delimiters-depth-2">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-2">)</span>, m_z<span class="org-rainbow-delimiters-depth-2">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-2">)</span>, <span class="org-string">'DisplayName', 'Marble - Z'</span><span class="org-rainbow-delimiters-depth-1">)</span>; plot<span class="org-rainbow-delimiters-depth-1">(</span>m_z<span class="org-rainbow-delimiters-depth-2">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-2">)</span>, m_z<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-2">)</span>, <span class="org-string">'DisplayName', 'Floor - Z'</span><span class="org-rainbow-delimiters-depth-1">)</span>; hold off; xlabel<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'Time </span><span class="org-string"><span class="org-rainbow-delimiters-depth-2">[</span></span><span class="org-string">s</span><span class="org-string"><span class="org-rainbow-delimiters-depth-2">]</span></span><span class="org-string">'</span><span class="org-string"><span class="org-rainbow-delimiters-depth-1">)</span></span><span class="org-string">; ylabel</span><span class="org-string"><span class="org-rainbow-delimiters-depth-1">(</span></span><span class="org-string">'Voltage </span><span class="org-string"><span class="org-rainbow-delimiters-depth-2">[</span></span><span class="org-string">V</span><span class="org-string"><span class="org-rainbow-delimiters-depth-2">]</span></span><span class="org-string">'</span><span class="org-rainbow-delimiters-depth-1">)</span>; xlim<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-rainbow-delimiters-depth-2">[</span><span class="org-highlight-numbers-number">0</span>, <span class="org-highlight-numbers-number">100</span><span class="org-rainbow-delimiters-depth-2">]</span><span class="org-rainbow-delimiters-depth-1">)</span>; ylim<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-rainbow-delimiters-depth-2">[</span><span class="org-type">-</span><span class="org-highlight-numbers-number">2</span> <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-2">]</span><span class="org-rainbow-delimiters-depth-1">)</span>; legend<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'Location', 'northeast'</span><span class="org-rainbow-delimiters-depth-1">)</span>; subplot<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-highlight-numbers-number">1</span>, <span class="org-highlight-numbers-number">3</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-1">)</span>; hold on; plot<span class="org-rainbow-delimiters-depth-1">(</span>m_n<span class="org-rainbow-delimiters-depth-2">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-2">)</span>, m_n<span class="org-rainbow-delimiters-depth-2">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-2">)</span>, <span class="org-string">'DisplayName', 'Marble - N'</span><span class="org-rainbow-delimiters-depth-1">)</span>; plot<span class="org-rainbow-delimiters-depth-1">(</span>m_n<span class="org-rainbow-delimiters-depth-2">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-2">)</span>, m_n<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-2">)</span>, <span class="org-string">'DisplayName', 'Floor - N'</span><span class="org-rainbow-delimiters-depth-1">)</span>; hold off; xlabel<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'Time </span><span class="org-string"><span class="org-rainbow-delimiters-depth-2">[</span></span><span class="org-string">s</span><span class="org-string"><span class="org-rainbow-delimiters-depth-2">]</span></span><span class="org-string">'</span><span class="org-string"><span class="org-rainbow-delimiters-depth-1">)</span></span><span class="org-string">; ylabel</span><span class="org-string"><span class="org-rainbow-delimiters-depth-1">(</span></span><span class="org-string">'Voltage </span><span class="org-string"><span class="org-rainbow-delimiters-depth-2">[</span></span><span class="org-string">V</span><span class="org-string"><span class="org-rainbow-delimiters-depth-2">]</span></span><span class="org-string">'</span><span class="org-rainbow-delimiters-depth-1">)</span>; xlim<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-rainbow-delimiters-depth-2">[</span><span class="org-highlight-numbers-number">0</span>, <span class="org-highlight-numbers-number">100</span><span class="org-rainbow-delimiters-depth-2">]</span><span class="org-rainbow-delimiters-depth-1">)</span>; ylim<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-rainbow-delimiters-depth-2">[</span><span class="org-type">-</span><span class="org-highlight-numbers-number">2</span> <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-2">]</span><span class="org-rainbow-delimiters-depth-1">)</span>; legend<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'Location', 'northeast'</span><span class="org-rainbow-delimiters-depth-1">)</span>; subplot<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-highlight-numbers-number">1</span>, <span class="org-highlight-numbers-number">3</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span>; hold on; plot<span class="org-rainbow-delimiters-depth-1">(</span>m_e<span class="org-rainbow-delimiters-depth-2">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-2">)</span>, m_e<span class="org-rainbow-delimiters-depth-2">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-2">)</span>, <span class="org-string">'DisplayName', 'Marble - E'</span><span class="org-rainbow-delimiters-depth-1">)</span>; plot<span class="org-rainbow-delimiters-depth-1">(</span>m_e<span class="org-rainbow-delimiters-depth-2">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-2">)</span>, m_e<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-2">)</span>, <span class="org-string">'DisplayName', 'Floor - E'</span><span class="org-rainbow-delimiters-depth-1">)</span>; hold off; xlabel<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'Time </span><span class="org-string"><span class="org-rainbow-delimiters-depth-2">[</span></span><span class="org-string">s</span><span class="org-string"><span class="org-rainbow-delimiters-depth-2">]</span></span><span class="org-string">'</span><span class="org-string"><span class="org-rainbow-delimiters-depth-1">)</span></span><span class="org-string">; ylabel</span><span class="org-string"><span class="org-rainbow-delimiters-depth-1">(</span></span><span class="org-string">'Voltage </span><span class="org-string"><span class="org-rainbow-delimiters-depth-2">[</span></span><span class="org-string">V</span><span class="org-string"><span class="org-rainbow-delimiters-depth-2">]</span></span><span class="org-string">'</span><span class="org-rainbow-delimiters-depth-1">)</span>; xlim<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-rainbow-delimiters-depth-2">[</span><span class="org-highlight-numbers-number">0</span>, <span class="org-highlight-numbers-number">100</span><span class="org-rainbow-delimiters-depth-2">]</span><span class="org-rainbow-delimiters-depth-1">)</span>; ylim<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-rainbow-delimiters-depth-2">[</span><span class="org-type">-</span><span class="org-highlight-numbers-number">2</span> <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-2">]</span><span class="org-rainbow-delimiters-depth-1">)</span>; legend<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'Location', 'northeast'</span><span class="org-rainbow-delimiters-depth-1">)</span>; </pre> </div> <div id="org10ef412" class="figure"> <p><img src="figs/marble_floor_motion_time.png" alt="marble_floor_motion_time.png" /> </p> <p><span class="figure-number">Figure 3: </span>Floor and ground motion</p> </div> </div> </div> <div id="outline-container-org32ab030" class="outline-3"> <h3 id="org32ab030"><span class="section-number-3">2.3</span> Compute the power spectral densities</h3> <div class="outline-text-3" id="text-2-3"> <p> We first compute some parameters that will be used for the PSD computation. </p> <div class="org-src-container"> <pre class="src src-matlab">dt = m_z<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-highlight-numbers-number">2</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span><span class="org-type">-</span>m_z<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-highlight-numbers-number">1</span>, <span class="org-highlight-numbers-number">3</span><span class="org-rainbow-delimiters-depth-1">)</span>; Fs = <span class="org-highlight-numbers-number">1</span><span class="org-type">/</span>dt; <span class="org-comment">% [Hz]</span> win = hanning<span class="org-rainbow-delimiters-depth-1">(</span>ceil<span class="org-rainbow-delimiters-depth-2">(</span><span class="org-highlight-numbers-number">10</span><span class="org-type">*</span>Fs<span class="org-rainbow-delimiters-depth-2">)</span><span class="org-rainbow-delimiters-depth-1">)</span>; </pre> </div> <p> Then we compute the Power Spectral Density using <code>pwelch</code> function. </p> <div class="org-src-container"> <pre class="src src-matlab"><span class="org-rainbow-delimiters-depth-1">[</span>px_fz, f<span class="org-rainbow-delimiters-depth-1">]</span> = pwelch<span class="org-rainbow-delimiters-depth-1">(</span>m_z<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-2">)</span>, win, <span class="org-rainbow-delimiters-depth-2">[]</span>, <span class="org-rainbow-delimiters-depth-2">[]</span>, Fs<span class="org-rainbow-delimiters-depth-1">)</span>; <span class="org-rainbow-delimiters-depth-1">[</span>px_gz, <span class="org-type">~</span><span class="org-rainbow-delimiters-depth-1">]</span> = pwelch<span class="org-rainbow-delimiters-depth-1">(</span>m_z<span class="org-rainbow-delimiters-depth-2">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-2">)</span>, win, <span class="org-rainbow-delimiters-depth-2">[]</span>, <span class="org-rainbow-delimiters-depth-2">[]</span>, Fs<span class="org-rainbow-delimiters-depth-1">)</span>; <span class="org-rainbow-delimiters-depth-1">[</span>px_fn, <span class="org-type">~</span><span class="org-rainbow-delimiters-depth-1">]</span> = pwelch<span class="org-rainbow-delimiters-depth-1">(</span>m_n<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-2">)</span>, win, <span class="org-rainbow-delimiters-depth-2">[]</span>, <span class="org-rainbow-delimiters-depth-2">[]</span>, Fs<span class="org-rainbow-delimiters-depth-1">)</span>; <span class="org-rainbow-delimiters-depth-1">[</span>px_gn, <span class="org-type">~</span><span class="org-rainbow-delimiters-depth-1">]</span> = pwelch<span class="org-rainbow-delimiters-depth-1">(</span>m_n<span class="org-rainbow-delimiters-depth-2">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-2">)</span>, win, <span class="org-rainbow-delimiters-depth-2">[]</span>, <span class="org-rainbow-delimiters-depth-2">[]</span>, Fs<span class="org-rainbow-delimiters-depth-1">)</span>; <span class="org-rainbow-delimiters-depth-1">[</span>px_fe, <span class="org-type">~</span><span class="org-rainbow-delimiters-depth-1">]</span> = pwelch<span class="org-rainbow-delimiters-depth-1">(</span>m_e<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-2">)</span>, win, <span class="org-rainbow-delimiters-depth-2">[]</span>, <span class="org-rainbow-delimiters-depth-2">[]</span>, Fs<span class="org-rainbow-delimiters-depth-1">)</span>; <span class="org-rainbow-delimiters-depth-1">[</span>px_ge, <span class="org-type">~</span><span class="org-rainbow-delimiters-depth-1">]</span> = pwelch<span class="org-rainbow-delimiters-depth-1">(</span>m_e<span class="org-rainbow-delimiters-depth-2">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-2">)</span>, win, <span class="org-rainbow-delimiters-depth-2">[]</span>, <span class="org-rainbow-delimiters-depth-2">[]</span>, Fs<span class="org-rainbow-delimiters-depth-1">)</span>; </pre> </div> <p> The results are shown on figure <a href="#org0484222">4</a> for the Z direction, figure <a href="#org691dab7">5</a> for the north direction, and figure <a href="#org0047fc8">6</a> for the east direction. </p> <div id="org0484222" class="figure"> <p><img src="figs/floor_marble_psd_z.png" alt="floor_marble_psd_z.png" /> </p> <p><span class="figure-number">Figure 4: </span>Amplitude Spectral Density of the measured voltage corresponding to the geophone located on the floor and on the marble - Z direction</p> </div> <div id="org691dab7" class="figure"> <p><img src="figs/floor_marble_psd_n.png" alt="floor_marble_psd_n.png" /> </p> <p><span class="figure-number">Figure 5: </span>Amplitude Spectral Density of the measured voltage corresponding to the geophone located on the floor and on the marble - N direction</p> </div> <div id="org0047fc8" class="figure"> <p><img src="figs/floor_marble_psd_e.png" alt="floor_marble_psd_e.png" /> </p> <p><span class="figure-number">Figure 6: </span>Amplitude Spectral Density of the measured voltage corresponding to the geophone located on the floor and on the marble - E direction</p> </div> </div> </div> <div id="outline-container-orgb8b258a" class="outline-3"> <h3 id="orgb8b258a"><span class="section-number-3">2.4</span> Compute the transfer function from floor motion to ground motion</h3> <div class="outline-text-3" id="text-2-4"> <p> We now compute the transfer function from the floor motion to the granite motion. </p> <p> The result is shown on figure <a href="#orgac80e8a">7</a>. </p> <div class="org-src-container"> <pre class="src src-matlab"><span class="org-rainbow-delimiters-depth-1">[</span>TZ, f<span class="org-rainbow-delimiters-depth-1">]</span> = tfestimate<span class="org-rainbow-delimiters-depth-1">(</span>m_z<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-2">)</span>, <span class="org-type">-</span>m_z<span class="org-rainbow-delimiters-depth-2">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-2">)</span>, win, <span class="org-rainbow-delimiters-depth-2">[]</span>, <span class="org-rainbow-delimiters-depth-2">[]</span>, Fs<span class="org-rainbow-delimiters-depth-1">)</span>; <span class="org-rainbow-delimiters-depth-1">[</span>TN, <span class="org-type">~</span><span class="org-rainbow-delimiters-depth-1">]</span> = tfestimate<span class="org-rainbow-delimiters-depth-1">(</span>m_n<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-2">)</span>, <span class="org-type">-</span>m_n<span class="org-rainbow-delimiters-depth-2">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-2">)</span>, win, <span class="org-rainbow-delimiters-depth-2">[]</span>, <span class="org-rainbow-delimiters-depth-2">[]</span>, Fs<span class="org-rainbow-delimiters-depth-1">)</span>; <span class="org-rainbow-delimiters-depth-1">[</span>TE, <span class="org-type">~</span><span class="org-rainbow-delimiters-depth-1">]</span> = tfestimate<span class="org-rainbow-delimiters-depth-1">(</span>m_e<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-2">)</span>, <span class="org-type">-</span>m_e<span class="org-rainbow-delimiters-depth-2">(</span><span class="org-type">:</span>, <span class="org-highlight-numbers-number">2</span><span class="org-rainbow-delimiters-depth-2">)</span>, win, <span class="org-rainbow-delimiters-depth-2">[]</span>, <span class="org-rainbow-delimiters-depth-2">[]</span>, Fs<span class="org-rainbow-delimiters-depth-1">)</span>; </pre> </div> <div id="orgac80e8a" class="figure"> <p><img src="figs/tf_granite.png" alt="tf_granite.png" /> </p> <p><span class="figure-number">Figure 7: </span>Transfer function from floor motion to granite motion</p> </div> </div> </div> <div id="outline-container-org806c2da" class="outline-3"> <h3 id="org806c2da"><span class="section-number-3">2.5</span> Conclusion</h3> <div class="outline-text-3" id="text-2-5"> <div class="important"> <ul class="org-ul"> <li>We see resonance of the granite at 33Hz in the horizontal directions</li> <li>We see two resonances for the z direction: at 60Hz and 75Hz</li> </ul> </div> </div> </div> </div> </div> <div id="postamble" class="status"> <p class="author">Author: Dehaeze Thomas</p> <p class="date">Created: 2019-05-14 mar. 11:25</p> <p class="validation"><a href="http://validator.w3.org/check?uri=referer">Validate</a></p> </div> </body> </html>