732 lines
		
	
	
		
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			732 lines
		
	
	
		
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<body>
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<div id="content">
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<h1 class="title">Cercalo Test Bench</h1>
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<div id="table-of-contents">
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<h2>Table of Contents</h2>
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<div id="text-table-of-contents">
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<ul>
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<li><a href="#orgff87b8d">1. Introduction</a></li>
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<li><a href="#org2459267">2. Identification</a>
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<ul>
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<li><a href="#org9b7ddaf">2.1. Excitation Data</a></li>
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<li><a href="#org04e353b">2.2. Huddle Test</a></li>
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<li><a href="#org4dc3ca0">2.3. Input / Output data</a></li>
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<li><a href="#org1f732b6">2.4. Estimation of the Frequency Response Function Matrix</a></li>
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<li><a href="#org8986a6a">2.5. Coherence</a></li>
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<li><a href="#orgb611053">2.6. Extraction of a transfer function matrix</a></li>
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</ul>
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</li>
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<li><a href="#org5cfd6fc">3. Sensor Noise</a></li>
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<li><a href="#org2bd416c">4. Plant Analysis</a>
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<ul>
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<li><a href="#orge74c87e">4.1. Rotation Matrix</a></li>
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</ul>
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</li>
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<li><a href="#org7b9c8d0">5. Control Objective</a></li>
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<li><a href="#orgbefa210">6. Plant Scaling</a></li>
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<li><a href="#org90e1042">7. Control Design</a></li>
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</ul>
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</div>
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</div>
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<div id="outline-container-orgff87b8d" class="outline-2">
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<h2 id="orgff87b8d"><span class="section-number-2">1</span> Introduction</h2>
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</div>
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<div id="outline-container-org2459267" class="outline-2">
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<h2 id="org2459267"><span class="section-number-2">2</span> Identification</h2>
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<div class="outline-text-2" id="text-2">
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<p>
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<a id="org1f481c7"></a>
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</p>
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<div class="note">
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<p>
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All the files (data and Matlab scripts) are accessible <a href="data/plant_identification.zip">here</a>.
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</p>
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</div>
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</div>
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<div id="outline-container-org9b7ddaf" class="outline-3">
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<h3 id="org9b7ddaf"><span class="section-number-3">2.1</span> Excitation Data</h3>
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<div class="outline-text-3" id="text-2-1">
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<div class="org-src-container">
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<pre class="src src-matlab">fs = <span class="org-highlight-numbers-number">1e4</span>;
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Ts = <span class="org-highlight-numbers-number">1</span><span class="org-type">/</span>fs;
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</pre>
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</div>
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<p>
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We generate white noise with the "random number" simulink block, and we filter that noise.
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</p>
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<div class="org-src-container">
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<pre class="src src-matlab">Gi = <span class="org-rainbow-delimiters-depth-1">(</span><span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-1">)</span><span class="org-type">/</span><span class="org-rainbow-delimiters-depth-1">(</span><span class="org-highlight-numbers-number">1</span><span class="org-type">+</span>s<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><span class="org-highlight-numbers-number">100</span><span class="org-rainbow-delimiters-depth-1">)</span>;
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</pre>
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</div>
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<div class="org-src-container">
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<pre class="src src-matlab">c2d<span class="org-rainbow-delimiters-depth-1">(</span>Gi, Ts, <span class="org-string">'tustin'</span><span class="org-rainbow-delimiters-depth-1">)</span>
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</pre>
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</div>
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<pre class="example">
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c2d(Gi, Ts, 'tustin')
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ans =
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  0.030459 (z+1)
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  --------------
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    (z-0.9391)
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Sample time: 0.0001 seconds
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Discrete-time zero/pole/gain model.
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</pre>
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</div>
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</div>
 | 
						|
 | 
						|
<div id="outline-container-org04e353b" class="outline-3">
 | 
						|
<h3 id="org04e353b"><span class="section-number-3">2.2</span> Huddle Test</h3>
 | 
						|
<div class="outline-text-3" id="text-2-2">
 | 
						|
<p>
 | 
						|
We load the data taken during the Huddle Test.
 | 
						|
</p>
 | 
						|
<div class="org-src-container">
 | 
						|
<pre class="src src-matlab">load<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'mat/data_huddle_test.mat', 't', 'xh', 'xv', 'cuh', 'cuv'</span><span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
</pre>
 | 
						|
</div>
 | 
						|
 | 
						|
<p>
 | 
						|
The variables are:
 | 
						|
</p>
 | 
						|
<dl class="org-dl">
 | 
						|
<dt>\(x_h\)</dt><dd>Normalized position of the beam in the horizontal direction as measured by the 4 quadrant diode</dd>
 | 
						|
<dt>\(x_v\)</dt><dd>Normalized position of the beam in the vertical direction as measured by the 4 quadrant diode</dd>
 | 
						|
<dt>\(cu_h\)</dt><dd>Voltage across the inductance used for the horizontal positioning of the Cercalo</dd>
 | 
						|
<dt>\(vu_v\)</dt><dd>Voltage across the inductance used for the vertical positioning of the Cercalo</dd>
 | 
						|
</dl>
 | 
						|
 | 
						|
<div class="org-src-container">
 | 
						|
<pre class="src src-matlab">xh<span class="org-rainbow-delimiters-depth-1">(</span>t<span class="org-type"><</span><span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-1">)</span> = <span class="org-rainbow-delimiters-depth-1">[]</span>;
 | 
						|
xv<span class="org-rainbow-delimiters-depth-1">(</span>t<span class="org-type"><</span><span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-1">)</span> = <span class="org-rainbow-delimiters-depth-1">[]</span>;
 | 
						|
cuh<span class="org-rainbow-delimiters-depth-1">(</span>t<span class="org-type"><</span><span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-1">)</span> = <span class="org-rainbow-delimiters-depth-1">[]</span>;
 | 
						|
cuv<span class="org-rainbow-delimiters-depth-1">(</span>t<span class="org-type"><</span><span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-1">)</span> = <span class="org-rainbow-delimiters-depth-1">[]</span>;
 | 
						|
t<span class="org-rainbow-delimiters-depth-1">(</span>t<span class="org-type"><</span><span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-1">)</span> = <span class="org-rainbow-delimiters-depth-1">[]</span>;
 | 
						|
t = t <span class="org-type">-</span> t<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-highlight-numbers-number">1</span><span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
</pre>
 | 
						|
</div>
 | 
						|
 | 
						|
<div class="org-src-container">
 | 
						|
<pre class="src src-matlab"><span class="org-rainbow-delimiters-depth-1">[</span>psd_xh, f<span class="org-rainbow-delimiters-depth-1">]</span> = pwelch<span class="org-rainbow-delimiters-depth-1">(</span>xh, hanning<span class="org-rainbow-delimiters-depth-2">(</span>ceil<span class="org-rainbow-delimiters-depth-3">(</span><span class="org-highlight-numbers-number">1</span><span class="org-type">*</span>fs<span class="org-rainbow-delimiters-depth-3">)</span><span class="org-rainbow-delimiters-depth-2">)</span>, <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>psd_xv, <span class="org-type">~</span><span class="org-rainbow-delimiters-depth-1">]</span> = pwelch<span class="org-rainbow-delimiters-depth-1">(</span>xv, hanning<span class="org-rainbow-delimiters-depth-2">(</span>ceil<span class="org-rainbow-delimiters-depth-3">(</span><span class="org-highlight-numbers-number">1</span><span class="org-type">*</span>fs<span class="org-rainbow-delimiters-depth-3">)</span><span class="org-rainbow-delimiters-depth-2">)</span>, <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 class="org-src-container">
 | 
						|
<pre class="src src-matlab"><span class="org-type">figure</span>;
 | 
						|
hold on;
 | 
						|
plot<span class="org-rainbow-delimiters-depth-1">(</span>f, sqrt<span class="org-rainbow-delimiters-depth-2">(</span>psd_xh<span class="org-rainbow-delimiters-depth-2">)</span>, <span class="org-string">'DisplayName', '</span>$<span class="org-type">\</span>Gamma_<span class="org-rainbow-delimiters-depth-2">{</span>x_h<span class="org-rainbow-delimiters-depth-2">}</span>$'<span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
plot<span class="org-rainbow-delimiters-depth-1">(</span>f, sqrt<span class="org-rainbow-delimiters-depth-2">(</span>psd_xv<span class="org-rainbow-delimiters-depth-2">)</span>, <span class="org-string">'DisplayName', '</span>$<span class="org-type">\</span>Gamma_<span class="org-rainbow-delimiters-depth-2">{</span>x_v<span class="org-rainbow-delimiters-depth-2">}</span>$'<span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
hold off;
 | 
						|
<span class="org-type">set</span><span class="org-rainbow-delimiters-depth-1">(</span><span class="org-variable-name">gca</span>, <span class="org-string">'xscale', 'log'</span><span class="org-string"><span class="org-rainbow-delimiters-depth-1">)</span></span><span class="org-string">; set</span><span class="org-string"><span class="org-rainbow-delimiters-depth-1">(</span></span><span class="org-string">gca, 'yscale', 'log'</span><span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
xlabel<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'Frequency </span><span class="org-string"><span class="org-rainbow-delimiters-depth-2">[</span></span><span class="org-string">Hz</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">'</span>ASD $<span class="org-type">\</span>left<span class="org-rainbow-delimiters-depth-2">[</span><span class="org-type">\</span>frac<span class="org-rainbow-delimiters-depth-3">{</span>V<span class="org-rainbow-delimiters-depth-3">}{</span><span class="org-type">\</span>sqrt<span class="org-rainbow-delimiters-depth-4">{</span>Hz<span class="org-rainbow-delimiters-depth-4">}</span><span class="org-rainbow-delimiters-depth-3">}</span><span class="org-type">\</span>right<span class="org-rainbow-delimiters-depth-2">]</span>$'<span class="org-rainbow-delimiters-depth-1">)</span>
 | 
						|
legend<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'Location', 'southwest'</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">1</span>, <span class="org-highlight-numbers-number">1000</span><span class="org-rainbow-delimiters-depth-2">]</span><span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
</pre>
 | 
						|
</div>
 | 
						|
 | 
						|
<div class="org-src-container">
 | 
						|
<pre class="src src-matlab"><span class="org-rainbow-delimiters-depth-1">[</span>psd_cuh, f<span class="org-rainbow-delimiters-depth-1">]</span> = pwelch<span class="org-rainbow-delimiters-depth-1">(</span>cuh, hanning<span class="org-rainbow-delimiters-depth-2">(</span>ceil<span class="org-rainbow-delimiters-depth-3">(</span><span class="org-highlight-numbers-number">1</span><span class="org-type">*</span>fs<span class="org-rainbow-delimiters-depth-3">)</span><span class="org-rainbow-delimiters-depth-2">)</span>, <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>psd_cuv, <span class="org-type">~</span><span class="org-rainbow-delimiters-depth-1">]</span> = pwelch<span class="org-rainbow-delimiters-depth-1">(</span>cuv, hanning<span class="org-rainbow-delimiters-depth-2">(</span>ceil<span class="org-rainbow-delimiters-depth-3">(</span><span class="org-highlight-numbers-number">1</span><span class="org-type">*</span>fs<span class="org-rainbow-delimiters-depth-3">)</span><span class="org-rainbow-delimiters-depth-2">)</span>, <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 class="org-src-container">
 | 
						|
<pre class="src src-matlab"><span class="org-type">figure</span>;
 | 
						|
hold on;
 | 
						|
plot<span class="org-rainbow-delimiters-depth-1">(</span>f, sqrt<span class="org-rainbow-delimiters-depth-2">(</span>psd_cuh<span class="org-rainbow-delimiters-depth-2">)</span>, <span class="org-string">'DisplayName', '</span>$<span class="org-type">\</span>Gamma_<span class="org-rainbow-delimiters-depth-2">{</span>cu_h<span class="org-rainbow-delimiters-depth-2">}</span>$'<span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
plot<span class="org-rainbow-delimiters-depth-1">(</span>f, sqrt<span class="org-rainbow-delimiters-depth-2">(</span>psd_cuv<span class="org-rainbow-delimiters-depth-2">)</span>, <span class="org-string">'DisplayName', '</span>$<span class="org-type">\</span>Gamma_<span class="org-rainbow-delimiters-depth-2">{</span>cu_v<span class="org-rainbow-delimiters-depth-2">}</span>$'<span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
hold off;
 | 
						|
<span class="org-type">set</span><span class="org-rainbow-delimiters-depth-1">(</span><span class="org-variable-name">gca</span>, <span class="org-string">'xscale', 'log'</span><span class="org-string"><span class="org-rainbow-delimiters-depth-1">)</span></span><span class="org-string">; set</span><span class="org-string"><span class="org-rainbow-delimiters-depth-1">(</span></span><span class="org-string">gca, 'yscale', 'log'</span><span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
xlabel<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'Frequency </span><span class="org-string"><span class="org-rainbow-delimiters-depth-2">[</span></span><span class="org-string">Hz</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">'</span>ASD $<span class="org-type">\</span>left<span class="org-rainbow-delimiters-depth-2">[</span><span class="org-type">\</span>frac<span class="org-rainbow-delimiters-depth-3">{</span>V<span class="org-rainbow-delimiters-depth-3">}{</span><span class="org-type">\</span>sqrt<span class="org-rainbow-delimiters-depth-4">{</span>Hz<span class="org-rainbow-delimiters-depth-4">}</span><span class="org-rainbow-delimiters-depth-3">}</span><span class="org-type">\</span>right<span class="org-rainbow-delimiters-depth-2">]</span>$'<span class="org-rainbow-delimiters-depth-1">)</span>
 | 
						|
legend<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'Location', 'southwest'</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">1</span>, <span class="org-highlight-numbers-number">1000</span><span class="org-rainbow-delimiters-depth-2">]</span><span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
</pre>
 | 
						|
</div>
 | 
						|
</div>
 | 
						|
</div>
 | 
						|
 | 
						|
<div id="outline-container-org4dc3ca0" class="outline-3">
 | 
						|
<h3 id="org4dc3ca0"><span class="section-number-3">2.3</span> Input / Output data</h3>
 | 
						|
<div class="outline-text-3" id="text-2-3">
 | 
						|
<p>
 | 
						|
The identification data is loaded
 | 
						|
</p>
 | 
						|
<div class="org-src-container">
 | 
						|
<pre class="src src-matlab">ux = load<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'mat/data_ux.mat', 't', 'ux', 'yx', 'yy'</span><span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
uy = load<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'mat/data_uy.mat', 't', 'uy', 'yx', 'yy'</span><span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
</pre>
 | 
						|
</div>
 | 
						|
 | 
						|
<p>
 | 
						|
We remove the first seconds where the Cercalo is turned on.
 | 
						|
</p>
 | 
						|
<div class="org-src-container">
 | 
						|
<pre class="src src-matlab">i0x = <span class="org-highlight-numbers-number">20</span><span class="org-type">*</span>fs;
 | 
						|
 | 
						|
i0y = <span class="org-highlight-numbers-number">10</span><span class="org-type">*</span>fs;
 | 
						|
 | 
						|
ux.t  = ux.t<span class="org-rainbow-delimiters-depth-1">(</span> i0x<span class="org-type">:</span>end<span class="org-rainbow-delimiters-depth-1">)</span> <span class="org-type">-</span> ux.t<span class="org-rainbow-delimiters-depth-1">(</span>i0x<span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
ux.ux = ux.ux<span class="org-rainbow-delimiters-depth-1">(</span>i0x<span class="org-type">:</span>end<span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
ux.yx = ux.yx<span class="org-rainbow-delimiters-depth-1">(</span>i0x<span class="org-type">:</span>end<span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
ux.yy = ux.yy<span class="org-rainbow-delimiters-depth-1">(</span>i0x<span class="org-type">:</span>end<span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
 | 
						|
uy.t  = uy.t<span class="org-rainbow-delimiters-depth-1">(</span> i0y<span class="org-type">:</span>end<span class="org-rainbow-delimiters-depth-1">)</span> <span class="org-type">-</span> uy.t<span class="org-rainbow-delimiters-depth-1">(</span>i0x<span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
uy.uy = uy.uy<span class="org-rainbow-delimiters-depth-1">(</span>i0y<span class="org-type">:</span>end<span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
uy.yx = uy.yx<span class="org-rainbow-delimiters-depth-1">(</span>i0y<span class="org-type">:</span>end<span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
uy.yy = uy.yy<span class="org-rainbow-delimiters-depth-1">(</span>i0y<span class="org-type">:</span>end<span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
</pre>
 | 
						|
</div>
 | 
						|
 | 
						|
<div class="org-src-container">
 | 
						|
<pre class="src src-matlab">ux.ux = ux.ux<span class="org-type">-</span>mean<span class="org-rainbow-delimiters-depth-1">(</span>ux.ux<span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
ux.yx = ux.yx<span class="org-type">-</span>mean<span class="org-rainbow-delimiters-depth-1">(</span>ux.yx<span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
ux.yy = ux.yy<span class="org-type">-</span>mean<span class="org-rainbow-delimiters-depth-1">(</span>ux.yy<span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
 | 
						|
uy.ux = uy.ux<span class="org-type">-</span>mean<span class="org-rainbow-delimiters-depth-1">(</span>uy.ux<span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
uy.yx = uy.yx<span class="org-type">-</span>mean<span class="org-rainbow-delimiters-depth-1">(</span>uy.yx<span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
uy.yy = uy.yy<span class="org-type">-</span>mean<span class="org-rainbow-delimiters-depth-1">(</span>uy.yy<span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
</pre>
 | 
						|
</div>
 | 
						|
 | 
						|
 | 
						|
<div id="org2d6aeb1" class="figure">
 | 
						|
<p><img src="figs/identification_ux.png" alt="identification_ux.png" />
 | 
						|
</p>
 | 
						|
<p><span class="figure-number">Figure 1: </span>Identification signals when exciting the \(x\) axis (<a href="./figs/identification_ux.png">png</a>, <a href="./figs/identification_ux.pdf">pdf</a>)</p>
 | 
						|
</div>
 | 
						|
 | 
						|
 | 
						|
 | 
						|
<div id="orgd5e71a4" class="figure">
 | 
						|
<p><img src="figs/identification_uy.png" alt="identification_uy.png" />
 | 
						|
</p>
 | 
						|
<p><span class="figure-number">Figure 2: </span>Identification signals when exciting the \(y\) axis (<a href="./figs/identification_uy.png">png</a>, <a href="./figs/identification_uy.pdf">pdf</a>)</p>
 | 
						|
</div>
 | 
						|
</div>
 | 
						|
</div>
 | 
						|
 | 
						|
<div id="outline-container-org1f732b6" class="outline-3">
 | 
						|
<h3 id="org1f732b6"><span class="section-number-3">2.4</span> Estimation of the Frequency Response Function Matrix</h3>
 | 
						|
<div class="outline-text-3" id="text-2-4">
 | 
						|
<p>
 | 
						|
We compute an estimate of the transfer functions.
 | 
						|
</p>
 | 
						|
<div class="org-src-container">
 | 
						|
<pre class="src src-matlab"><span class="org-rainbow-delimiters-depth-1">[</span>tf_ux_yx, f<span class="org-rainbow-delimiters-depth-1">]</span> = tfestimate<span class="org-rainbow-delimiters-depth-1">(</span>ux.ux, ux.yx, hanning<span class="org-rainbow-delimiters-depth-2">(</span>ceil<span class="org-rainbow-delimiters-depth-3">(</span><span class="org-highlight-numbers-number">1</span><span class="org-type">*</span>fs<span class="org-rainbow-delimiters-depth-3">)</span><span class="org-rainbow-delimiters-depth-2">)</span>, <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>tf_ux_yy, <span class="org-type">~</span><span class="org-rainbow-delimiters-depth-1">]</span> = tfestimate<span class="org-rainbow-delimiters-depth-1">(</span>ux.ux, ux.yy, hanning<span class="org-rainbow-delimiters-depth-2">(</span>ceil<span class="org-rainbow-delimiters-depth-3">(</span><span class="org-highlight-numbers-number">1</span><span class="org-type">*</span>fs<span class="org-rainbow-delimiters-depth-3">)</span><span class="org-rainbow-delimiters-depth-2">)</span>, <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>tf_uy_yx, <span class="org-type">~</span><span class="org-rainbow-delimiters-depth-1">]</span> = tfestimate<span class="org-rainbow-delimiters-depth-1">(</span>uy.uy, uy.yx, hanning<span class="org-rainbow-delimiters-depth-2">(</span>ceil<span class="org-rainbow-delimiters-depth-3">(</span><span class="org-highlight-numbers-number">1</span><span class="org-type">*</span>fs<span class="org-rainbow-delimiters-depth-3">)</span><span class="org-rainbow-delimiters-depth-2">)</span>, <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>tf_uy_yy, <span class="org-type">~</span><span class="org-rainbow-delimiters-depth-1">]</span> = tfestimate<span class="org-rainbow-delimiters-depth-1">(</span>uy.uy, uy.yy, hanning<span class="org-rainbow-delimiters-depth-2">(</span>ceil<span class="org-rainbow-delimiters-depth-3">(</span><span class="org-highlight-numbers-number">1</span><span class="org-type">*</span>fs<span class="org-rainbow-delimiters-depth-3">)</span><span class="org-rainbow-delimiters-depth-2">)</span>, <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="org2051377" class="figure">
 | 
						|
<p><img src="figs/frequency_response_matrix.png" alt="frequency_response_matrix.png" />
 | 
						|
</p>
 | 
						|
<p><span class="figure-number">Figure 3: </span>Frequency Response Matrix (<a href="./figs/frequency_response_matrix.png">png</a>, <a href="./figs/frequency_response_matrix.pdf">pdf</a>)</p>
 | 
						|
</div>
 | 
						|
</div>
 | 
						|
</div>
 | 
						|
 | 
						|
<div id="outline-container-org8986a6a" class="outline-3">
 | 
						|
<h3 id="org8986a6a"><span class="section-number-3">2.5</span> Coherence</h3>
 | 
						|
<div class="outline-text-3" id="text-2-5">
 | 
						|
<div class="org-src-container">
 | 
						|
<pre class="src src-matlab"><span class="org-rainbow-delimiters-depth-1">[</span>coh_ux_yx, f<span class="org-rainbow-delimiters-depth-1">]</span> = mscohere<span class="org-rainbow-delimiters-depth-1">(</span>ux.ux, ux.yx, hanning<span class="org-rainbow-delimiters-depth-2">(</span>ceil<span class="org-rainbow-delimiters-depth-3">(</span><span class="org-highlight-numbers-number">1</span><span class="org-type">*</span>fs<span class="org-rainbow-delimiters-depth-3">)</span><span class="org-rainbow-delimiters-depth-2">)</span>, <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>coh_ux_yy, <span class="org-type">~</span><span class="org-rainbow-delimiters-depth-1">]</span> = mscohere<span class="org-rainbow-delimiters-depth-1">(</span>ux.ux, ux.yy, hanning<span class="org-rainbow-delimiters-depth-2">(</span>ceil<span class="org-rainbow-delimiters-depth-3">(</span><span class="org-highlight-numbers-number">1</span><span class="org-type">*</span>fs<span class="org-rainbow-delimiters-depth-3">)</span><span class="org-rainbow-delimiters-depth-2">)</span>, <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>coh_uy_yx, <span class="org-type">~</span><span class="org-rainbow-delimiters-depth-1">]</span> = mscohere<span class="org-rainbow-delimiters-depth-1">(</span>uy.uy, uy.yx, hanning<span class="org-rainbow-delimiters-depth-2">(</span>ceil<span class="org-rainbow-delimiters-depth-3">(</span><span class="org-highlight-numbers-number">1</span><span class="org-type">*</span>fs<span class="org-rainbow-delimiters-depth-3">)</span><span class="org-rainbow-delimiters-depth-2">)</span>, <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>coh_uy_yy, <span class="org-type">~</span><span class="org-rainbow-delimiters-depth-1">]</span> = mscohere<span class="org-rainbow-delimiters-depth-1">(</span>uy.uy, uy.yy, hanning<span class="org-rainbow-delimiters-depth-2">(</span>ceil<span class="org-rainbow-delimiters-depth-3">(</span><span class="org-highlight-numbers-number">1</span><span class="org-type">*</span>fs<span class="org-rainbow-delimiters-depth-3">)</span><span class="org-rainbow-delimiters-depth-2">)</span>, <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="orgf0f9ad1" class="figure">
 | 
						|
<p><img src="figs/identification_coherence.png" alt="identification_coherence.png" />
 | 
						|
</p>
 | 
						|
<p><span class="figure-number">Figure 4: </span>Coherence (<a href="./figs/identification_coherence.png">png</a>, <a href="./figs/identification_coherence.pdf">pdf</a>)</p>
 | 
						|
</div>
 | 
						|
</div>
 | 
						|
</div>
 | 
						|
 | 
						|
 | 
						|
<div id="outline-container-orgb611053" class="outline-3">
 | 
						|
<h3 id="orgb611053"><span class="section-number-3">2.6</span> Extraction of a transfer function matrix</h3>
 | 
						|
<div class="outline-text-3" id="text-2-6">
 | 
						|
<p>
 | 
						|
First we define the initial guess for the resonance frequencies and the weights associated.
 | 
						|
</p>
 | 
						|
<div class="org-src-container">
 | 
						|
<pre class="src src-matlab">freqs_res = <span class="org-rainbow-delimiters-depth-1">[</span><span class="org-highlight-numbers-number">410</span>, <span class="org-highlight-numbers-number">250</span><span class="org-rainbow-delimiters-depth-1">]</span>; <span class="org-comment">% [Hz]</span>
 | 
						|
freqs_res_weights = <span class="org-rainbow-delimiters-depth-1">[</span><span class="org-highlight-numbers-number">10</span>, <span class="org-highlight-numbers-number">10</span><span class="org-rainbow-delimiters-depth-1">]</span>; <span class="org-comment">% [Hz]</span>
 | 
						|
</pre>
 | 
						|
</div>
 | 
						|
 | 
						|
<p>
 | 
						|
From the number of resonance frequency we want to fit, we define the order <code>N</code> of the system we want to obtain.
 | 
						|
</p>
 | 
						|
<div class="org-src-container">
 | 
						|
<pre class="src src-matlab">N = <span class="org-highlight-numbers-number">2</span><span class="org-type">*</span>length<span class="org-rainbow-delimiters-depth-1">(</span>freqs_res<span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
</pre>
 | 
						|
</div>
 | 
						|
 | 
						|
<p>
 | 
						|
We then make an initial guess on the complex values of the poles.
 | 
						|
</p>
 | 
						|
<div class="org-src-container">
 | 
						|
<pre class="src src-matlab">xi = <span class="org-highlight-numbers-number">0</span>.<span class="org-highlight-numbers-number">001</span>; <span class="org-comment">% Approximate modal damping</span>
 | 
						|
poles = <span class="org-rainbow-delimiters-depth-1">[</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>freqs_res<span class="org-type">*</span><span class="org-rainbow-delimiters-depth-2">(</span>xi <span class="org-type">+</span> <span class="org-highlight-numbers-number">1i</span><span class="org-rainbow-delimiters-depth-2">)</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>freqs_res<span class="org-type">*</span><span class="org-rainbow-delimiters-depth-2">(</span>xi <span class="org-type">-</span> <span class="org-highlight-numbers-number">1i</span><span class="org-rainbow-delimiters-depth-2">)</span><span class="org-rainbow-delimiters-depth-1">]</span>;
 | 
						|
</pre>
 | 
						|
</div>
 | 
						|
 | 
						|
<p>
 | 
						|
We then define the weight that will be used for the fitting.
 | 
						|
Basically, we want more weight around the resonance and at low frequency (below the first resonance).
 | 
						|
Also, we want more importance where we have a better coherence.
 | 
						|
</p>
 | 
						|
<div class="org-src-container">
 | 
						|
<pre class="src src-matlab">weight = ones<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-highlight-numbers-number">1</span>, length<span class="org-rainbow-delimiters-depth-2">(</span>f<span class="org-rainbow-delimiters-depth-2">)</span><span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
<span class="org-comment">% weight = G_coh';</span>
 | 
						|
 | 
						|
% alpha = <span class="org-highlight-numbers-number">0</span>.<span class="org-highlight-numbers-number">1</span>;
 | 
						|
 | 
						|
% <span class="org-keyword">for</span> <span class="org-variable-name">freq_i</span> = <span class="org-constant"><span class="org-highlight-numbers-number">1</span></span><span class="org-constant">:length(freqs_res)</span>
 | 
						|
%   weight(f<span class="org-type">></span>(<span class="org-highlight-numbers-number">1</span><span class="org-type">-</span>alpha)<span class="org-type">*</span>freqs_res(freq_i) <span class="org-type">&</span> omega<span class="org-type"><</span>(<span class="org-highlight-numbers-number">1</span> <span class="org-type">+</span> alpha)<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>freqs_res(freq_i)) = freqs_res_weights(freq_i);
 | 
						|
<span class="org-comment">% end</span>
 | 
						|
</pre>
 | 
						|
</div>
 | 
						|
 | 
						|
<p>
 | 
						|
Ignore data above some frequency.
 | 
						|
</p>
 | 
						|
<div class="org-src-container">
 | 
						|
<pre class="src src-matlab">weight<span class="org-rainbow-delimiters-depth-1">(</span>f<span class="org-type">></span><span class="org-highlight-numbers-number">1000</span><span class="org-rainbow-delimiters-depth-1">)</span> = <span class="org-highlight-numbers-number">0</span>;
 | 
						|
</pre>
 | 
						|
</div>
 | 
						|
 | 
						|
 | 
						|
<div id="org9d870b3" class="figure">
 | 
						|
<p><img src="figs/weights.png" alt="weights.png" />
 | 
						|
</p>
 | 
						|
<p><span class="figure-number">Figure 5: </span>Weights amplitude (<a href="./figs/weights.png">png</a>, <a href="./figs/weights.pdf">pdf</a>)</p>
 | 
						|
</div>
 | 
						|
 | 
						|
<p>
 | 
						|
When we set some options for <code>vfit3</code>.
 | 
						|
</p>
 | 
						|
<div class="org-src-container">
 | 
						|
<pre class="src src-matlab">opts = struct<span class="org-rainbow-delimiters-depth-1">()</span>;
 | 
						|
 | 
						|
opts.stable = <span class="org-highlight-numbers-number">1</span>;    <span class="org-comment">% Enforce stable poles</span>
 | 
						|
opts.asymp = <span class="org-highlight-numbers-number">1</span>;     <span class="org-comment">% Force D matrix to be null</span>
 | 
						|
opts.relax = <span class="org-highlight-numbers-number">1</span>;     <span class="org-comment">% Use vector fitting with relaxed non-triviality constraint</span>
 | 
						|
opts.skip_pole = <span class="org-highlight-numbers-number">0</span>; <span class="org-comment">% Do NOT skip pole identification</span>
 | 
						|
opts.skip_res = <span class="org-highlight-numbers-number">0</span>;  <span class="org-comment">% Do NOT skip identification of residues (C,D,E)</span>
 | 
						|
opts.cmplx_ss = <span class="org-highlight-numbers-number">0</span>;  <span class="org-comment">% Create real state space model with block diagonal A</span>
 | 
						|
 | 
						|
opts.spy1 = <span class="org-highlight-numbers-number">0</span>;      <span class="org-comment">% No plotting for first stage of vector fitting</span>
 | 
						|
opts.spy2 = <span class="org-highlight-numbers-number">0</span>;      <span class="org-comment">% Create magnitude plot for fitting of f(s)</span>
 | 
						|
</pre>
 | 
						|
</div>
 | 
						|
 | 
						|
<p>
 | 
						|
We define the number of iteration.
 | 
						|
</p>
 | 
						|
<div class="org-src-container">
 | 
						|
<pre class="src src-matlab">Niter = <span class="org-highlight-numbers-number">5</span>;
 | 
						|
</pre>
 | 
						|
</div>
 | 
						|
 | 
						|
<p>
 | 
						|
An we run the <code>vectfit3</code> algorithm.
 | 
						|
</p>
 | 
						|
<div class="org-src-container">
 | 
						|
<pre class="src src-matlab"><span class="org-keyword">for</span> <span class="org-variable-name">iter</span> = <span class="org-constant"><span class="org-highlight-numbers-number">1</span></span><span class="org-constant">:Niter</span>
 | 
						|
  <span class="org-rainbow-delimiters-depth-1">[</span>SER_ux_yx, poles, <span class="org-type">~</span>, fit_ux_yx<span class="org-rainbow-delimiters-depth-1">]</span> = vectfit3<span class="org-rainbow-delimiters-depth-1">(</span>tf_ux_yx<span class="org-type">.'</span>, <span class="org-highlight-numbers-number">1i</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>f, poles, weight, opts<span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
<span class="org-keyword">end</span>
 | 
						|
<span class="org-keyword">for</span> <span class="org-variable-name">iter</span> = <span class="org-constant"><span class="org-highlight-numbers-number">1</span></span><span class="org-constant">:Niter</span>
 | 
						|
  <span class="org-rainbow-delimiters-depth-1">[</span>SER_uy_yx, poles, <span class="org-type">~</span>, fit_uy_yx<span class="org-rainbow-delimiters-depth-1">]</span> = vectfit3<span class="org-rainbow-delimiters-depth-1">(</span>tf_uy_yx<span class="org-type">.'</span>, <span class="org-highlight-numbers-number">1i</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>f, poles, weight, opts<span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
<span class="org-keyword">end</span>
 | 
						|
<span class="org-keyword">for</span> <span class="org-variable-name">iter</span> = <span class="org-constant"><span class="org-highlight-numbers-number">1</span></span><span class="org-constant">:Niter</span>
 | 
						|
  <span class="org-rainbow-delimiters-depth-1">[</span>SER_ux_yy, poles, <span class="org-type">~</span>, fit_ux_yy<span class="org-rainbow-delimiters-depth-1">]</span> = vectfit3<span class="org-rainbow-delimiters-depth-1">(</span>tf_ux_yy<span class="org-type">.'</span>, <span class="org-highlight-numbers-number">1i</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>f, poles, weight, opts<span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
<span class="org-keyword">end</span>
 | 
						|
<span class="org-keyword">for</span> <span class="org-variable-name">iter</span> = <span class="org-constant"><span class="org-highlight-numbers-number">1</span></span><span class="org-constant">:Niter</span>
 | 
						|
  <span class="org-rainbow-delimiters-depth-1">[</span>SER_uy_yy, poles, <span class="org-type">~</span>, fit_uy_yy<span class="org-rainbow-delimiters-depth-1">]</span> = vectfit3<span class="org-rainbow-delimiters-depth-1">(</span>tf_uy_yy<span class="org-type">.'</span>, <span class="org-highlight-numbers-number">1i</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>f, poles, weight, opts<span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
<span class="org-keyword">end</span>
 | 
						|
</pre>
 | 
						|
</div>
 | 
						|
 | 
						|
 | 
						|
<div id="orgce7fc34" class="figure">
 | 
						|
<p><img src="figs/identification_matrix_fit.png" alt="identification_matrix_fit.png" />
 | 
						|
</p>
 | 
						|
<p><span class="figure-number">Figure 6: </span>Transfer Function Extraction of the FRF matrix (<a href="./figs/identification_matrix_fit.png">png</a>, <a href="./figs/identification_matrix_fit.pdf">pdf</a>)</p>
 | 
						|
</div>
 | 
						|
 | 
						|
<p>
 | 
						|
And finally, we create the identified state space model:
 | 
						|
</p>
 | 
						|
<div class="org-src-container">
 | 
						|
<pre class="src src-matlab">G_ux_yx = minreal<span class="org-rainbow-delimiters-depth-1">(</span>ss<span class="org-rainbow-delimiters-depth-2">(</span>full<span class="org-rainbow-delimiters-depth-3">(</span>SER_ux_yx.A<span class="org-rainbow-delimiters-depth-3">)</span>,SER_ux_yx.B,SER_ux_yx.C,SER_ux_yx.D<span class="org-rainbow-delimiters-depth-2">)</span><span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
G_uy_yx = minreal<span class="org-rainbow-delimiters-depth-1">(</span>ss<span class="org-rainbow-delimiters-depth-2">(</span>full<span class="org-rainbow-delimiters-depth-3">(</span>SER_uy_yx.A<span class="org-rainbow-delimiters-depth-3">)</span>,SER_uy_yx.B,SER_uy_yx.C,SER_uy_yx.D<span class="org-rainbow-delimiters-depth-2">)</span><span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
G_ux_yy = minreal<span class="org-rainbow-delimiters-depth-1">(</span>ss<span class="org-rainbow-delimiters-depth-2">(</span>full<span class="org-rainbow-delimiters-depth-3">(</span>SER_ux_yy.A<span class="org-rainbow-delimiters-depth-3">)</span>,SER_ux_yy.B,SER_ux_yy.C,SER_ux_yy.D<span class="org-rainbow-delimiters-depth-2">)</span><span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
G_uy_yy = minreal<span class="org-rainbow-delimiters-depth-1">(</span>ss<span class="org-rainbow-delimiters-depth-2">(</span>full<span class="org-rainbow-delimiters-depth-3">(</span>SER_uy_yy.A<span class="org-rainbow-delimiters-depth-3">)</span>,SER_uy_yy.B,SER_uy_yy.C,SER_uy_yy.D<span class="org-rainbow-delimiters-depth-2">)</span><span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
 | 
						|
G = <span class="org-rainbow-delimiters-depth-1">[</span>G_ux_yx, G_uy_yx;
 | 
						|
     G_ux_yy, G_uy_yy<span class="org-rainbow-delimiters-depth-1">]</span>;
 | 
						|
</pre>
 | 
						|
</div>
 | 
						|
 | 
						|
<div class="org-src-container">
 | 
						|
<pre class="src src-matlab">save<span class="org-rainbow-delimiters-depth-1">(</span><span class="org-string">'mat/plant.mat', 'G'</span><span class="org-rainbow-delimiters-depth-1">)</span>;
 | 
						|
</pre>
 | 
						|
</div>
 | 
						|
</div>
 | 
						|
</div>
 | 
						|
</div>
 | 
						|
 | 
						|
<div id="outline-container-org5cfd6fc" class="outline-2">
 | 
						|
<h2 id="org5cfd6fc"><span class="section-number-2">3</span> Sensor Noise</h2>
 | 
						|
</div>
 | 
						|
<div id="outline-container-org2bd416c" class="outline-2">
 | 
						|
<h2 id="org2bd416c"><span class="section-number-2">4</span> Plant Analysis</h2>
 | 
						|
<div class="outline-text-2" id="text-4">
 | 
						|
</div>
 | 
						|
<div id="outline-container-orge74c87e" class="outline-3">
 | 
						|
<h3 id="orge74c87e"><span class="section-number-3">4.1</span> Rotation Matrix</h3>
 | 
						|
<div class="outline-text-3" id="text-4-1">
 | 
						|
<div class="org-src-container">
 | 
						|
<pre class="src src-matlab">G0 = freqresp<span class="org-rainbow-delimiters-depth-1">(</span>G, <span class="org-highlight-numbers-number">0</span><span class="org-rainbow-delimiters-depth-1">)</span>;
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</pre>
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</div>
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</div>
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</div>
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</div>
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<div id="outline-container-org7b9c8d0" class="outline-2">
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						|
<h2 id="org7b9c8d0"><span class="section-number-2">5</span> Control Objective</h2>
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						|
<div class="outline-text-2" id="text-5">
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						|
<p>
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						|
The maximum expected stroke is \(y_\text{max} = 3mm \approx 5e^{-2} rad\) at \(1Hz\).
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						|
The maximum wanted error is \(e_\text{max} = 10 \mu rad\).
 | 
						|
</p>
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						|
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						|
<p>
 | 
						|
Thus, we require the sensitivity function at \(\omega_0 = 1\text{ Hz}\):
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						|
</p>
 | 
						|
\begin{align*}
 | 
						|
  |S(j\omega_0)| &< \left| \frac{e_\text{max}}{y_\text{max}} \right| \\
 | 
						|
                 &< 2 \cdot 10^{-4}
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						|
\end{align*}
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						|
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						|
<p>
 | 
						|
In terms of loop gain, this is equivalent to:
 | 
						|
\[ |L(j\omega_0)| > 5 \cdot 10^{3} \]
 | 
						|
</p>
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						|
</div>
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						|
</div>
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						|
 | 
						|
<div id="outline-container-orgbefa210" class="outline-2">
 | 
						|
<h2 id="orgbefa210"><span class="section-number-2">6</span> Plant Scaling</h2>
 | 
						|
<div class="outline-text-2" id="text-6">
 | 
						|
<ul class="org-ul">
 | 
						|
<li>measured noise</li>
 | 
						|
<li>expected perturbations</li>
 | 
						|
<li>maximum input usage</li>
 | 
						|
<li>maximum wanted error</li>
 | 
						|
</ul>
 | 
						|
</div>
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						|
</div>
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						|
 | 
						|
<div id="outline-container-org90e1042" class="outline-2">
 | 
						|
<h2 id="org90e1042"><span class="section-number-2">7</span> Control Design</h2>
 | 
						|
</div>
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						|
</div>
 | 
						|
<div id="postamble" class="status">
 | 
						|
<p class="author">Author: Dehaeze Thomas</p>
 | 
						|
<p class="date">Created: 2019-09-12 jeu. 15:20</p>
 | 
						|
<p class="validation"><a href="http://validator.w3.org/check?uri=referer">Validate</a></p>
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</div>
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</body>
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</html>
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