Table of Contents
@@ -57,26 +66,26 @@
-
+
-
Figure 1: Picture of the Setup
+
-
Figure 2: Zoom on the APA
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1 Setup
+
+
-
1 Setup
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1.1 Parameters
+
+
-
1.1 Parameters
Ts = 1e-4; @@ -85,8 +94,8 @@
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1.2 Filter White Noise
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+
-
1.2 Filter White Noise
Glpf = 1/(1 + s/2/pi/500); @@ -98,13 +107,13 @@ Gz = c2d(Glpf, Ts, 'tustin');
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2 Run Experiment and Save Data
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+
-
2 Run Experiment and Save Data
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2.1 Load Data
+
+
-
2.1 Load Data
data = SimulinkRealTime.utils.getFileScopeData('data/apa95ml.dat').data;
@@ -113,8 +122,8 @@ Gz = c2d(Glpf, Ts, 'tustin');
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2.2 Save Data
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+
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2.2 Save Data
u = data(:, 1); % Input Voltage [V] @@ -131,16 +140,16 @@ t = data(:, 3); % Time [s]
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3 Huddle Test
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+
-
3 Huddle Test
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3.1 Time Domain Data
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+
3.1 Time Domain Data
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+
-
Figure 3: Measurement of the Mass displacement during Huddle Test
@@ -148,8 +157,8 @@ t = data(:, 3); % Time [s]
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3.2 PSD of Measurement Noise
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+
-
3.2 PSD of Measurement Noise
Ts = t(end)/(length(t)-1); @@ -165,7 +174,7 @@ win = hanning(ceil(1*Fs));
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-
Figure 4: Amplitude Spectral Density of the Displacement during Huddle Test
@@ -174,16 +183,16 @@ win = hanning(ceil(1*Fs));
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4 Transfer Function Estimation with m=5kg
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+
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4 Transfer Function Estimation with \(m=5kg\)
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4.1 Time Domain Data
+
+
4.1 Time Domain Data
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+
-
Figure 5: Time domain signals during the test
@@ -191,8 +200,8 @@ win = hanning(ceil(1*Fs));
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4.2 Comparison of the PSD with Huddle Test
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+
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4.2 Comparison of the PSD with Huddle Test
Ts = t(end)/(length(t)-1); @@ -209,7 +218,7 @@ win = hanning(ceil(1*Fs));
+
-
Figure 6: Comparison of the ASD for the identification test and the huddle test
@@ -217,8 +226,8 @@ win = hanning(ceil(1*Fs));
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4.3 Compute TF estimate and Coherence
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+
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4.3 Compute TF estimate and Coherence
win = hann(ceil(1/Ts)); @@ -229,25 +238,42 @@ win = hanning(ceil(1*Fs));
+
-
+
+
Figure 7: Coherence
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Figure 8: Estimation of the transfer function from input voltage to displacement
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4.4 Comparison with the FEM model
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+
+
+
+
+
+load('mat/fem_model_5kg.mat', 'Ghm');
+
+
+
+
+
Figure 9: Comparison of the identified transfer function and the one estimated from the FE model
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-
diff --git a/index.org b/index.org
index aa5688a..991c82e 100644
--- a/index.org
+++ b/index.org
@@ -156,7 +156,7 @@
#+RESULTS:
[[file:figs/huddle_test_pdf.png]]
-* Transfer Function Estimation with m=5kg
+* Transfer Function Estimation with $m=5kg$
:PROPERTIES:
:header-args:matlab+: :tangle matlab/tf_estimation.m
:header-args:matlab+: :comments org :mkdirp yes
@@ -290,3 +290,40 @@
#+caption: Estimation of the transfer function from input voltage to displacement
#+RESULTS:
[[file:figs/apa95ml_5kg_10V_tf.png]]
+
+** Comparison with the FEM model
+#+begin_src matlab
+ load('mat/fem_model_5kg.mat', 'Ghm');
+#+end_src
+
+#+begin_src matlab :exports none
+ figure;
+ ax1 = subplot(2, 1, 1);
+ hold on;
+ plot(f, abs(tf_est), 'DisplayName', 'Identification')
+ plot(f, abs(squeeze(freqresp(Ghm, f, 'Hz'))), 'DisplayName', 'FEM')
+ set(gca, 'Xscale', 'log'); set(gca, 'Yscale', 'log');
+ ylabel('Amplitude'); xlabel('Frequency [Hz]');
+ legend('location', 'northeast')
+ hold off;
+
+ ax2 = subplot(2, 1, 2);
+ hold on;
+ plot(f, 180/pi*angle(tf_est))
+ plot(f, 180/pi*angle(squeeze(freqresp(Ghm, f, 'Hz'))))
+ set(gca, 'Xscale', 'log'); set(gca, 'Yscale', 'lin');
+ ylabel('Phase'); xlabel('Frequency [Hz]');
+ hold off;
+
+ linkaxes([ax1,ax2], 'x');
+ xlim([10, 5e3]);
+#+end_src
+
+#+begin_src matlab :tangle no :exports results :results file replace
+ exportFig('figs/apa95ml_5kg_comp_fem.pdf', 'width', 'full', 'height', 'full');
+#+end_src
+
+#+name: fig:apa95ml_5kg_comp_fem
+#+caption: Comparison of the identified transfer function and the one estimated from the FE model
+#+RESULTS:
+[[file:figs/apa95ml_5kg_comp_fem.png]]
diff --git a/mat/fem_model_5kg.mat b/mat/fem_model_5kg.mat
new file mode 100644
index 0000000..281b5b6
Binary files /dev/null and b/mat/fem_model_5kg.mat differ
Created: 2020-07-20 lun. 13:22
+Created: 2020-07-20 lun. 13:29