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<title>Amplifier Piezoelectric Actuator APA300ML - Test Bench</title>
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<h1 class="title">Amplifier Piezoelectric Actuator APA300ML - Test Bench</h1>
<div id="table-of-contents">
<h2>Table of Contents</h2>
<div id="text-table-of-contents">
<ul>
<li><a href="#org0eb094b">1. Model of an Amplified Piezoelectric Actuator and Sensor</a></li>
<li><a href="#org6f9ba21">2. Geometrical Measurements</a>
<ul>
<li><a href="#org8044086">2.1. Measurement Setup</a></li>
<li><a href="#org4293145">2.2. Measurement Results</a></li>
</ul>
</li>
<li><a href="#org50d4352">3. Electrical Measurements</a></li>
<li><a href="#orgb8a1481">4. Stiffness measurement</a>
<ul>
<li><a href="#org21bc9b2">4.1. APA test</a></li>
</ul>
</li>
<li><a href="#orgb3154e0">5. Test-Bench Description</a></li>
<li><a href="#orgac581ad">6. Measurement Procedure</a>
<ul>
<li><a href="#orge00396f">6.1. Stroke Measurement</a></li>
<li><a href="#org66ac5bb">6.2. Stiffness Measurement</a></li>
<li><a href="#orgee2d3e8">6.3. Hysteresis measurement</a></li>
<li><a href="#orge6e89ca">6.4. Piezoelectric Actuator Constant</a></li>
<li><a href="#orge970d07">6.5. Piezoelectric Sensor Constant</a></li>
<li><a href="#org86b3954">6.6. Capacitance Measurement</a></li>
<li><a href="#orgc5205df">6.7. Dynamical Behavior</a></li>
<li><a href="#org2f73a1b">6.8. Compare the results obtained for all 7 APA300ML</a></li>
</ul>
</li>
<li><a href="#org175e8d0">7. Measurement Results</a></li>
</ul>
</div>
</div>
<hr>
<p>This report is also available as a <a href="./test-bench-apa300ml.pdf">pdf</a>.</p>
<hr>
<p>
The goal of this test bench is to extract all the important parameters of the Amplified Piezoelectric Actuator APA300ML.
</p>
<p>
This include:
</p>
<ul class="org-ul">
<li>Stroke</li>
<li>Stiffness</li>
<li>Hysteresis</li>
<li>Gain from the applied voltage \(V_a\) to the generated Force \(F_a\)</li>
<li>Gain from the sensor stack strain \(\delta L\) to the generated voltage \(V_s\)</li>
<li>Dynamical behavior</li>
</ul>
<div id="org664d1fb" class="figure">
<p><img src="figs/apa300ML.png" alt="apa300ML.png" />
</p>
<p><span class="figure-number">Figure 1: </span>Picture of the APA300ML</p>
</div>
<div id="outline-container-org0eb094b" class="outline-2">
<h2 id="org0eb094b"><span class="section-number-2">1</span> Model of an Amplified Piezoelectric Actuator and Sensor</h2>
<div class="outline-text-2" id="text-1">
<p>
Consider a schematic of the Amplified Piezoelectric Actuator in Figure <a href="#orgc9df44d">2</a>.
</p>
<div id="orgc9df44d" class="figure">
<p><img src="figs/apa_model_schematic.png" alt="apa_model_schematic.png" />
</p>
<p><span class="figure-number">Figure 2: </span>Amplified Piezoelectric Actuator Schematic</p>
</div>
<p>
A voltage \(V_a\) applied to the actuator stacks will induce an actuator force \(F_a\):
</p>
\begin{equation}
F_a = g_a \cdot V_a
\end{equation}
<p>
A change of length \(dl\) of the sensor stack will induce a voltage \(V_s\):
</p>
\begin{equation}
V_s = g_s \cdot dl
\end{equation}
<p>
We wish here to experimental measure \(g_a\) and \(g_s\).
</p>
<p>
The block-diagram model of the piezoelectric actuator is then as shown in Figure <a href="#orgc4bba98">3</a>.
</p>
<div id="orgc4bba98" class="figure">
<p><img src="figs/apa-model-simscape-schematic.png" alt="apa-model-simscape-schematic.png" />
</p>
<p><span class="figure-number">Figure 3: </span>Model of the APA with Simscape/Simulink</p>
</div>
</div>
</div>
<div id="outline-container-org6f9ba21" class="outline-2">
<h2 id="org6f9ba21"><span class="section-number-2">2</span> Geometrical Measurements</h2>
<div class="outline-text-2" id="text-2">
<div id="org939ac64" class="figure">
<p><img src="figs/IMG_20210224_143500.jpg" alt="IMG_20210224_143500.jpg" />
</p>
<p><span class="figure-number">Figure 4: </span>Received APA</p>
</div>
</div>
<div id="outline-container-org8044086" class="outline-3">
<h3 id="org8044086"><span class="section-number-3">2.1</span> Measurement Setup</h3>
<div class="outline-text-3" id="text-2-1">
<div id="org43d857b" class="figure">
<p><img src="figs/IMG_20210224_143809.jpg" alt="IMG_20210224_143809.jpg" />
</p>
<p><span class="figure-number">Figure 5: </span>Measurement Setup</p>
</div>
</div>
</div>
<div id="outline-container-org4293145" class="outline-3">
<h3 id="org4293145"><span class="section-number-3">2.2</span> Measurement Results</h3>
<div class="outline-text-3" id="text-2-2">
<p>
Height (Z) measurements:
</p>
<div class="org-src-container">
<pre class="src src-matlab">apa1 = 1e<span class="org-type">-</span>6<span class="org-type">*</span>[0, <span class="org-type">-</span>0.5 , 3.5 , 3.5 , 42 , 45.5, 52.5 , 46];
apa2 = 1e<span class="org-type">-</span>6<span class="org-type">*</span>[0, <span class="org-type">-</span>2.5 , <span class="org-type">-</span>3 , 0 , <span class="org-type">-</span>1.5 , 1 , <span class="org-type">-</span>2 , <span class="org-type">-</span>4];
apa3 = 1e<span class="org-type">-</span>6<span class="org-type">*</span>[0, <span class="org-type">-</span>1.5 , 15 , 17.5 , 6.5 , 6.5 , 21 , 23];
apa4 = 1e<span class="org-type">-</span>6<span class="org-type">*</span>[0, 6.5 , 14.5 , 9 , 16 , 22 , 29.5 , 21];
apa5 = 1e<span class="org-type">-</span>6<span class="org-type">*</span>[0, <span class="org-type">-</span>12.5, 16.5 , 28.5 , <span class="org-type">-</span>43 , <span class="org-type">-</span>52 , <span class="org-type">-</span>22.5, <span class="org-type">-</span>13.5];
apa6 = 1e<span class="org-type">-</span>6<span class="org-type">*</span>[0, <span class="org-type">-</span>8 , <span class="org-type">-</span>2 , 5 , <span class="org-type">-</span>57.5, <span class="org-type">-</span>62 , <span class="org-type">-</span>55.5, <span class="org-type">-</span>52.5];
apa7 = 1e<span class="org-type">-</span>6<span class="org-type">*</span>[0, 19.5 , <span class="org-type">-</span>8 , <span class="org-type">-</span>29.5, 75 , 97.5, 70 , 48];
apa7b = 1e<span class="org-type">-</span>6<span class="org-type">*</span>[0, 9 , <span class="org-type">-</span>18.5, <span class="org-type">-</span>30 , 31 , 46.5, 16.5 , 7.5];
apa = {apa1, apa2, apa3, apa4, apa5, apa6, apa7b};
</pre>
</div>
<p>
X/Y Positions of the 8 measurement points:
</p>
<div class="org-src-container">
<pre class="src src-matlab">W = 20e<span class="org-type">-</span>3; <span class="org-comment">% Width [m]</span>
L = 61e<span class="org-type">-</span>3; <span class="org-comment">% Length [m]</span>
d = 1e<span class="org-type">-</span>3; <span class="org-comment">% Distance from border [m]</span>
l = 15.5e<span class="org-type">-</span>3; <span class="org-comment">% [m]</span>
pos = [[<span class="org-type">-</span>L<span class="org-type">/</span>2 <span class="org-type">+</span> d; W<span class="org-type">/</span>2 <span class="org-type">-</span> d], [<span class="org-type">-</span>L<span class="org-type">/</span>2 <span class="org-type">+</span> l <span class="org-type">-</span> d; W<span class="org-type">/</span>2 <span class="org-type">-</span> d], [<span class="org-type">-</span>L<span class="org-type">/</span>2 <span class="org-type">+</span> l <span class="org-type">-</span> d; <span class="org-type">-</span>W<span class="org-type">/</span>2 <span class="org-type">+</span> d], [<span class="org-type">-</span>L<span class="org-type">/</span>2 <span class="org-type">+</span> d; <span class="org-type">-</span>W<span class="org-type">/</span>2 <span class="org-type">+</span> d], [L<span class="org-type">/</span>2 <span class="org-type">-</span> l <span class="org-type">+</span> d; W<span class="org-type">/</span>2 <span class="org-type">-</span> d], [L<span class="org-type">/</span>2 <span class="org-type">-</span> d; W<span class="org-type">/</span>2 <span class="org-type">-</span> d], [L<span class="org-type">/</span>2 <span class="org-type">-</span> d; <span class="org-type">-</span>W<span class="org-type">/</span>2 <span class="org-type">+</span> d], [L<span class="org-type">/</span>2 <span class="org-type">-</span> l <span class="org-type">+</span> d; <span class="org-type">-</span>W<span class="org-type">/</span>2 <span class="org-type">+</span> d]];
</pre>
</div>
<div class="org-src-container">
<pre class="src src-matlab">apa_d = zeros(1, 7);
<span class="org-keyword">for</span> <span class="org-variable-name"><span class="org-constant">i</span></span> = <span class="org-constant">1:7</span>
fun = @(x)max(abs(([pos; apa{<span class="org-constant">i</span>}]<span class="org-type">-</span>[0;0;x(1)])<span class="org-type">'*</span>([x(2<span class="org-type">:</span>3);1]<span class="org-type">/</span>norm([x(2<span class="org-type">:</span>3);1]))));
x0 = [0;0;0];
[x, min_d] = fminsearch(fun,x0);
apa_d(<span class="org-constant">i</span>) = min_d;
<span class="org-keyword">end</span>
</pre>
</div>
<table id="org2443ab1" border="2" cellspacing="0" cellpadding="6" rules="groups" frame="hsides">
<caption class="t-above"><span class="table-number">Table 1:</span> Estimated flatness</caption>
<colgroup>
<col class="org-right" />
</colgroup>
<thead>
<tr>
<th scope="col" class="org-right">Flatness [um]</th>
</tr>
</thead>
<tbody>
<tr>
<td class="org-right">8.9</td>
</tr>
<tr>
<td class="org-right">3.1</td>
</tr>
<tr>
<td class="org-right">9.1</td>
</tr>
<tr>
<td class="org-right">3.0</td>
</tr>
<tr>
<td class="org-right">1.9</td>
</tr>
<tr>
<td class="org-right">7.1</td>
</tr>
<tr>
<td class="org-right">18.7</td>
</tr>
</tbody>
</table>
</div>
</div>
</div>
<div id="outline-container-org50d4352" class="outline-2">
<h2 id="org50d4352"><span class="section-number-2">3</span> Electrical Measurements</h2>
<div class="outline-text-2" id="text-3">
<div class="note" id="org262a984">
<p>
The capacitance of the stacks is measure with the <a href="https://www.gwinstek.com/en-global/products/detail/LCR-800">LCR-800 Meter</a> (<a href="doc/DS_LCR-800_Series_V2_E.pdf">doc</a>)
</p>
</div>
<div id="orgdaa55e5" class="figure">
<p><img src="figs/IMG_20210312_120337.jpg" alt="IMG_20210312_120337.jpg" />
</p>
<p><span class="figure-number">Figure 6: </span>LCR Meter used for the measurements</p>
</div>
<p>
The excitation frequency is set to be 1kHz.
</p>
<table id="org9d7793d" border="2" cellspacing="0" cellpadding="6" rules="groups" frame="hsides">
<caption class="t-above"><span class="table-number">Table 2:</span> Capacitance measured with the LCR meter. The excitation signal is a sinus at 1kHz</caption>
<colgroup>
<col class="org-right" />
<col class="org-right" />
<col class="org-right" />
</colgroup>
<thead>
<tr>
<th scope="col" class="org-right"><b>APA Number</b></th>
<th scope="col" class="org-right"><b>Sensor Stack</b></th>
<th scope="col" class="org-right"><b>Actuator Stacks</b></th>
</tr>
</thead>
<tbody>
<tr>
<td class="org-right">1</td>
<td class="org-right">5.10</td>
<td class="org-right">10.03</td>
</tr>
<tr>
<td class="org-right">2</td>
<td class="org-right">4.99</td>
<td class="org-right">9.85</td>
</tr>
<tr>
<td class="org-right">3</td>
<td class="org-right">1.72</td>
<td class="org-right">5.18</td>
</tr>
<tr>
<td class="org-right">4</td>
<td class="org-right">4.94</td>
<td class="org-right">9.82</td>
</tr>
<tr>
<td class="org-right">5</td>
<td class="org-right">4.90</td>
<td class="org-right">9.66</td>
</tr>
<tr>
<td class="org-right">6</td>
<td class="org-right">4.99</td>
<td class="org-right">9.91</td>
</tr>
<tr>
<td class="org-right">7</td>
<td class="org-right">4.85</td>
<td class="org-right">9.85</td>
</tr>
</tbody>
</table>
<div class="warning" id="org5042148">
<p>
There is clearly a problem with APA300ML number 3
</p>
</div>
</div>
</div>
<div id="outline-container-orgb8a1481" class="outline-2">
<h2 id="orgb8a1481"><span class="section-number-2">4</span> Stiffness measurement</h2>
<div class="outline-text-2" id="text-4">
</div>
<div id="outline-container-org21bc9b2" class="outline-3">
<h3 id="org21bc9b2"><span class="section-number-3">4.1</span> APA test</h3>
<div class="outline-text-3" id="text-4-1">
<div class="org-src-container">
<pre class="src src-matlab">load(<span class="org-string">'meas_stiff_apa_1_x.mat'</span>, <span class="org-string">'t'</span>, <span class="org-string">'F'</span>, <span class="org-string">'d'</span>);
</pre>
</div>
<div class="org-src-container">
<pre class="src src-matlab"><span class="org-type">figure</span>;
plot(t, F)
</pre>
</div>
<div class="org-src-container">
<pre class="src src-matlab"><span class="org-matlab-cellbreak"><span class="org-comment">%% Automatic Zero of the force</span></span>
F = F <span class="org-type">-</span> mean(F(t <span class="org-type">&gt;</span> 0.1 <span class="org-type">&amp;</span> t <span class="org-type">&lt;</span> 0.3));
<span class="org-matlab-cellbreak"><span class="org-comment">%% Start measurement at t = 0.2 s</span></span>
d = d(t <span class="org-type">&gt;</span> 0.2);
F = F(t <span class="org-type">&gt;</span> 0.2);
t = t(t <span class="org-type">&gt;</span> 0.2); t = t <span class="org-type">-</span> t(1);
</pre>
</div>
<div class="org-src-container">
<pre class="src src-matlab">i_l_start = find(F <span class="org-type">&gt;</span> 0.3, 1, <span class="org-string">'first'</span>);
[<span class="org-type">~</span>, i_l_stop] = max(F);
</pre>
</div>
<div class="org-src-container">
<pre class="src src-matlab">F_l = F(i_l_start<span class="org-type">:</span>i_l_stop);
d_l = d(i_l_start<span class="org-type">:</span>i_l_stop);
</pre>
</div>
<div class="org-src-container">
<pre class="src src-matlab">fit_l = polyfit(F_l, d_l, 1);
<span class="org-comment">% %% Reset displacement based on fit</span>
<span class="org-comment">% d = d - fit_l(2);</span>
<span class="org-comment">% fit_s(2) = fit_s(2) - fit_l(2);</span>
<span class="org-comment">% fit_l(2) = 0;</span>
<span class="org-comment">% %% Estimated Stroke</span>
<span class="org-comment">% F_max = fit_s(2)/(fit_l(1) - fit_s(1));</span>
<span class="org-comment">% d_max = fit_l(1)*F_max;</span>
</pre>
</div>
<div class="org-src-container">
<pre class="src src-matlab">h<span class="org-type">^</span>2<span class="org-type">/</span>fit_l(1)
</pre>
</div>
<div class="org-src-container">
<pre class="src src-matlab"><span class="org-type">figure</span>;
hold on;
plot(F,d,<span class="org-string">'k'</span>)
plot(F_l, d_l)
plot(F_l, F_l<span class="org-type">*</span>fit_l(1) <span class="org-type">+</span> fit_l(2), <span class="org-string">'--'</span>)
</pre>
</div>
</div>
</div>
</div>
<div id="outline-container-orgb3154e0" class="outline-2">
<h2 id="orgb3154e0"><span class="section-number-2">5</span> Test-Bench Description</h2>
<div class="outline-text-2" id="text-5">
<div class="note" id="orgc87eff8">
<p>
Here are the documentation of the equipment used for this test bench:
</p>
<ul class="org-ul">
<li>Voltage Amplifier: <a href="doc/PD200-V7-R1.pdf">PD200</a></li>
<li>Amplified Piezoelectric Actuator: <a href="doc/APA300ML.pdf">APA300ML</a></li>
<li>DAC/ADC: Speedgoat <a href="doc/IO131-OEM-Datasheet.pdf">IO313</a></li>
<li>Encoder: <a href="doc/L-9517-9678-05-A_Data_sheet_VIONiC_series_en.pdf">Renishaw Vionic</a> and used <a href="doc/L-9517-9862-01-C_Data_sheet_RKLC_EN.pdf">Ruler</a></li>
<li>Interferometer: <a href="https://www.attocube.com/en/products/laser-displacement-sensor/displacement-measuring-interferometer">Attocube IDS3010</a></li>
</ul>
</div>
<div id="orgfd15602" class="figure">
<p><img src="figs/test_bench_apa_alone.png" alt="test_bench_apa_alone.png" />
</p>
<p><span class="figure-number">Figure 7: </span>Schematic of the Test Bench</p>
</div>
</div>
</div>
<div id="outline-container-orgac581ad" class="outline-2">
<h2 id="orgac581ad"><span class="section-number-2">6</span> Measurement Procedure</h2>
<div class="outline-text-2" id="text-6">
</div>
<div id="outline-container-orge00396f" class="outline-3">
<h3 id="orge00396f"><span class="section-number-3">6.1</span> Stroke Measurement</h3>
<div class="outline-text-3" id="text-6-1">
<p>
Using the PD200 amplifier, output a voltage:
\[ V_a = 65 + 85 \sin(2\pi \cdot t) \]
To have a quasi-static excitation between -20 and 150V.
</p>
<p>
As the gain of the PD200 amplifier is 20, the DAC output voltage should be:
\[ V_{dac}(t) = 3.25 + 4.25\sin(2\pi \cdot t) \]
</p>
<p>
Verify that the voltage offset of the PD200 is zero!
</p>
<p>
Measure the output vertical displacement \(d\) using the interferometer.
</p>
<p>
Then, plot \(d\) as a function of \(V_a\), and perform a linear regression.
Conclude on the obtained stroke.
</p>
</div>
</div>
<div id="outline-container-org66ac5bb" class="outline-3">
<h3 id="org66ac5bb"><span class="section-number-3">6.2</span> Stiffness Measurement</h3>
<div class="outline-text-3" id="text-6-2">
<p>
Add some (known) weight \(\delta m g\) on the suspended mass and measure the deflection \(\delta d\).
This can be tested when the piezoelectric stacks are open-circuit.
</p>
<p>
As the stiffness will be around \(k \approx 10^6 N/m\), an added mass of \(m \approx 100g\) will induce a static deflection of \(\approx 1\mu m\) which should be large enough for a precise measurement using the interferometer.
</p>
<p>
Then the obtained stiffness is:
</p>
\begin{equation}
k = \frac{\delta m g}{\delta d}
\end{equation}
</div>
</div>
<div id="outline-container-orgee2d3e8" class="outline-3">
<h3 id="orgee2d3e8"><span class="section-number-3">6.3</span> Hysteresis measurement</h3>
<div class="outline-text-3" id="text-6-3">
<p>
Supply a quasi static sinusoidal excitation \(V_a\) at different voltages.
</p>
<p>
The offset should be 65V, and the sin amplitude can range from 1V up to 85V.
</p>
<p>
For each excitation amplitude, the vertical displacement \(d\) of the mass is measured.
</p>
<p>
Then, \(d\) is plotted as a function of \(V_a\) for all the amplitudes.
</p>
<div id="org7123135" class="figure">
<p><img src="figs/expected_hysteresis.png" alt="expected_hysteresis.png" />
</p>
<p><span class="figure-number">Figure 8: </span>Expected Hysteresis (<a class='org-ref-reference' href="#poel10_explor_activ_hard_mount_vibrat">poel10_explor_activ_hard_mount_vibrat</a>)</p>
</div>
</div>
</div>
<div id="outline-container-orge6e89ca" class="outline-3">
<h3 id="orge6e89ca"><span class="section-number-3">6.4</span> Piezoelectric Actuator Constant</h3>
<div class="outline-text-3" id="text-6-4">
<p>
Using the measurement test-bench, it is rather easy the determine the static gain between the applied voltage \(V_a\) to the induced displacement \(d\).
Use a quasi static (1Hz) excitation signal \(V_a\) on the piezoelectric stack and measure the vertical displacement \(d\).
Perform a linear regression to obtain:
</p>
\begin{equation}
d = g_{d/V_a} \cdot V_a
\end{equation}
<p>
Using the Simscape model of the APA, it is possible to determine the static gain between the actuator force \(F_a\) to the induced displacement \(d\):
</p>
\begin{equation}
d = g_{d/F_a} \cdot F_a
\end{equation}
<p>
From the two gains, it is then easy to determine \(g_a\):
</p>
\begin{equation}
g_a = \frac{F_a}{V_a} = \frac{F_a}{d} \cdot \frac{d}{V_a} = \frac{g_{d/V_a}}{g_{d/F_a}}
\end{equation}
</div>
</div>
<div id="outline-container-orge970d07" class="outline-3">
<h3 id="orge970d07"><span class="section-number-3">6.5</span> Piezoelectric Sensor Constant</h3>
<div class="outline-text-3" id="text-6-5">
<p>
From a quasi static excitation of the piezoelectric stack, measure the gain from \(V_a\) to \(V_s\):
</p>
\begin{equation}
V_s = g_{V_s/V_a} V_a
\end{equation}
<p>
Note here that there is an high pass filter formed by the piezo capacitor and parallel resistor.
The excitation frequency should then be in between the cut-off frequency of this high pass filter and the first resonance.
</p>
<p>
Alternatively, the gain can be computed from the dynamical identification and taking the gain at the wanted frequency.
</p>
<p>
Using the simscape model, compute the static gain from the actuator force \(F_a\) to the strain of the sensor stack \(dl\):
</p>
\begin{equation}
dl = g_{dl/F_a} F_a
\end{equation}
<p>
Then, the static gain from the sensor stack strain \(dl\) to the general voltage \(V_s\) is:
</p>
\begin{equation}
g_s = \frac{V_s}{dl} = \frac{V_s}{V_a} \cdot \frac{V_a}{F_a} \cdot \frac{F_a}{dl} = \frac{g_{V_s/V_a}}{g_a \cdot g_{dl/F_a}}
\end{equation}
<p>
Alternatively, we could impose an external force to add strain in the APA that should be equally present in all the 3 stacks and equal to 1/5 of the vertical strain.
This external force can be some weight added, or a piezo in parallel.
</p>
</div>
</div>
<div id="outline-container-org86b3954" class="outline-3">
<h3 id="org86b3954"><span class="section-number-3">6.6</span> Capacitance Measurement</h3>
<div class="outline-text-3" id="text-6-6">
<p>
Measure the capacitance of the 3 stacks individually using a precise multi-meter.
</p>
</div>
</div>
<div id="outline-container-orgc5205df" class="outline-3">
<h3 id="orgc5205df"><span class="section-number-3">6.7</span> Dynamical Behavior</h3>
<div class="outline-text-3" id="text-6-7">
<p>
Perform a system identification from \(V_a\) to the measured displacement \(d\) by the interferometer and by the encoder, and to the generated voltage \(V_s\).
</p>
<p>
This can be performed using different excitation signals.
</p>
<p>
This can also be performed with and without the encoder fixed to the APA.
</p>
</div>
</div>
<div id="outline-container-org2f73a1b" class="outline-3">
<h3 id="org2f73a1b"><span class="section-number-3">6.8</span> Compare the results obtained for all 7 APA300ML</h3>
<div class="outline-text-3" id="text-6-8">
<p>
Compare all the obtained parameters for all the test APA.
</p>
</div>
</div>
</div>
<div id="outline-container-org175e8d0" class="outline-2">
<h2 id="org175e8d0"><span class="section-number-2">7</span> Measurement Results</h2>
</div>
<style>.csl-entry{text-indent: -1.5em; margin-left: 1.5em;}</style><h2 class='citeproc-org-bib-h2'>Bibliography</h2>
<div class="csl-bib-body">
<div class="csl-entry"><a name="citeproc_bib_item_1"></a>Souleille, Adrien, Thibault Lampert, V Lafarga, Sylvain Hellegouarch, Alan Rondineau, Gonçalo Rodrigues, and Christophe Collette. 2018. “A Concept of Active Mount for Space Applications.” <i>CEAS Space Journal</i> 10 (2). Springer:157–65.</div>
</div>
</div>
<div id="postamble" class="status">
<p class="author">Author: Dehaeze Thomas</p>
<p class="date">Created: 2021-03-15 lun. 11:35</p>
</div>
</body>
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