Renamed one folder. Add analysis of vibrations when rotating

index.org

@@ -73,6 +73,9 @@ The station is identified again.
 #+end_important
 
 * Measurements of perturbations
+- [[file:slip-ring-spindle-vibrations/index.org][Measurement of the vibrations induced by the rotation of the slip-ring and spindle]]
+- Measurement of the electrical noise induced by the slip-ring
+
 ** Noise coming from the control loop of each stage
 [[file:2018-10-15%20-%20Marc/index.org][Link to the analysis]]
 
@@ -135,12 +138,11 @@ The goal is to estimate all the error motions induced by the Spindle
 
 *** Results
 
-* Ressources
-- [[file:actuators-sensors/index.org][Actuators and Sensors]]
-- [[file:equipment/equipment.org][Equipment used for the measurements]]
-
 * Other measurements
 - [[file:huddle-test-geophones/index.org][Huddle Test - Geophones]]
 - [[file:disturbance-measurement/index.org][Disturbance Measurement]]
 - [[file:slip-ring-test/index.org][Slip Ring - Noise measurement]]
 - [[file:static-measurements/index.org][Control System Measurement]]
+* Ressources
+- [[file:actuators-sensors/index.org][Actuators and Sensors]]
+- [[file:equipment/equipment.org][Equipment used for the measurements]]

slip-ring-electrical-noise/index.org

@@ -289,6 +289,7 @@ We now look at the difference between the signal directly measured by the ADC an
   - Should the measurement be redone using voltage amplifiers?
   - Use higher rotation speed and measure for longer periods (to have multiple revolutions) ?
 #+end_note
+
 * Measure of the noise induced by the Slip-Ring
   :PROPERTIES:
   :header-args:matlab+: :tangle matlab/meas_slip_ring.m

slip-ring-electrical-noise/readme.org

@@ -88,4 +88,3 @@ Measurements:
 - meas21: Slip-Ring ON
 - meas22: Slip-Ring ON and omega=6rpm
 - meas23: Slip-Ring ON and omega=60rpm
-

slip-ring-spindle-vibrations/index.org

@@ -0,0 +1,205 @@
+#+TITLE: Vibrations induced by the Slip-Ring and the Spindle
+#+SETUPFILE: ../config.org
+
+* Experimental Setup
+All the stages are OFF.
+
+Two geophone are use:
+- One on the marble (corresponding to the first column in the data)
+- One at the sample location (corresponding to the second column in the data)
+
+Two voltage amplifiers are used, their setup is:
+- gain of 60dB
+- AC/DC switch on AC
+- Low pass filter at 1kHz
+
+A first order low pass filter is also added at the input of the voltage amplifiers.
+
+*Goal*:
+- Identify the vibrations induced by the rotation of the Slip-Ring and Spindle
+
+Three measurements are done:
+- =mat/data_024.mat=: All the stages are OFF
+- =mat/data_025.mat=: The slip-ring is ON and rotates at 6rpm. The spindle is OFF
+- =mat/data_026.mat=: The slip-ring and spindle are both ON. They are both turning at 6rpm
+
+A movie showing the experiment is shown on figure [[fig:exp_sl_sp_gif]].
+
+#+name: fig:exp_sl_sp_gif
+#+attr_html: :width 300px
+#+caption: Movie of the experiment, rotation speed is 6rpm
+[[file:./img/VID_20190510_155655.gif]]
+
+* Data Analysis
+  :PROPERTIES:
+  :header-args:matlab+: :tangle matlab/spindle_slip_ring_vibrations.m
+  :header-args:matlab+: :comments org :mkdirp yes
+  :END:
+  <<sec:spindle_slip_ring_vibrations>>
+
+#+begin_src bash :exports none :results none
+  if [ matlab/spindle_slip_ring_vibrations.m -nt data/spindle_slip_ring_vibrations.zip ]; then
+    cp matlab/spindle_slip_ring_vibrations.m spindle_slip_ring_vibrations.m;
+    zip data/spindle_slip_ring_vibrations \
+        mat/data_024.mat \
+        mat/data_025.mat \
+        mat/data_026.mat \
+        spindle_slip_ring_vibrations.m
+    rm spindle_slip_ring_vibrations.m;
+  fi
+#+end_src
+
+#+begin_note
+  All the files (data and Matlab scripts) are accessible [[file:data/spindle_slip_ring_vibrations.zip][here]].
+#+end_note
+
+** Matlab Init                                              :noexport:ignore:
+#+begin_src matlab :tangle no :exports none :results silent :noweb yes :var current_dir=(file-name-directory buffer-file-name)
+<<matlab-dir>>
+#+end_src
+
+#+begin_src matlab :exports none :results silent :noweb yes
+<<matlab-init>>
+#+end_src
+
+** Load data
+#+begin_src matlab
+  of = load('mat/data_024.mat', 'data'); of = of.data;
+  sr = load('mat/data_025.mat', 'data'); sr = sr.data;
+  sp = load('mat/data_026.mat', 'data'); sp = sp.data;
+#+end_src
+
+** Time domain plots
+#+begin_src matlab
+  figure;
+  hold on;
+  plot(sp(:, 3), sp(:, 1), 'DisplayName', 'Spindle - 6rpm');
+  plot(sr(:, 3), sr(:, 1), 'DisplayName', 'Slip-Ring - 6rpm');
+  plot(of(:, 3), of(:, 1), 'DisplayName', 'OFF');
+  hold off;
+  xlabel('Time [s]'); ylabel('Voltage [V]');
+  xlim([0, 100]); ylim([-10 10]);
+  legend('Location', 'northeast');
+#+end_src
+
+#+NAME: fig:slip_ring_spindle_marble_time
+#+HEADER: :tangle no :exports results :results value raw replace :noweb yes
+#+begin_src matlab :var filepath="figs/slip_ring_spindle_marble_time.pdf" :var figsize="wide-normal" :post pdf2svg(file=*this*, ext="png")
+  <<plt-matlab>>
+#+end_src
+
+#+NAME: fig:slip_ring_spindle_marble_time
+#+CAPTION: Measurement of the geophone located on the marble - Time domain
+#+RESULTS: fig:slip_ring_spindle_marble_time
+[[file:figs/slip_ring_spindle_marble_time.png]]
+
+#+begin_src matlab
+  figure;
+  hold on;
+  plot(sp(:, 3), sp(:, 2), 'DisplayName', 'Spindle and Slip-Ring');
+  plot(sr(:, 3), sr(:, 2), 'DisplayName', 'Only Slip-Ring');
+  plot(of(:, 3), of(:, 2), 'DisplayName', 'OFF');
+  hold off;
+  xlabel('Time [s]'); ylabel('Voltage [V]');
+  xlim([0, 100]); ylim([-10 10]);
+  legend('Location', 'northeast');
+#+end_src
+
+#+NAME: fig:slip_ring_spindle_sample_time
+#+HEADER: :tangle no :exports results :results value raw replace :noweb yes
+#+begin_src matlab :var filepath="figs/slip_ring_spindle_sample_time.pdf" :var figsize="wide-normal" :post pdf2svg(file=*this*, ext="png")
+  <<plt-matlab>>
+#+end_src
+
+#+NAME: fig:slip_ring_spindle_sample_time
+#+CAPTION: Measurement of the geophone at the sample location - Time domain
+#+RESULTS: fig:slip_ring_spindle_sample_time
+[[file:figs/slip_ring_spindle_sample_time.png]]
+
+** Frequency Domain
+We first compute some parameters that will be used for the PSD computation.
+#+begin_src matlab :results none
+  dt = of(2, 3)-of(1, 3);
+
+  Fs = 1/dt; % [Hz]
+
+  win = hanning(ceil(10*Fs));
+#+end_src
+
+Then we compute the Power Spectral Density using =pwelch= function.
+
+First for the geophone located on the marble
+#+begin_src matlab
+  [pxof_m, f] = pwelch(of(:, 1), win, [], [], Fs);
+  [pxsr_m, ~] = pwelch(sr(:, 1), win, [], [], Fs);
+  [pxsp_m, ~] = pwelch(sp(:, 1), win, [], [], Fs);
+#+end_src
+
+And for the geophone located at the sample position.
+#+begin_src matlab
+  [pxof_s, f] = pwelch(of(:, 2), win, [], [], Fs);
+  [pxsr_s, ~] = pwelch(sr(:, 2), win, [], [], Fs);
+  [pxsp_s, ~] = pwelch(sp(:, 2), win, [], [], Fs);
+#+end_src
+
+And we plot the ASD of the measured signals:
+- figure [[fig:sr_sp_psd_marble_compare]] for the geophone located on the marble
+- figure [[fig:sr_sp_psd_sample_compare]] for the geophone at the sample position
+
+#+begin_src matlab :results none
+  figure;
+  hold on;
+  plot(f, sqrt(pxsp_m), 'DisplayName', 'Spindle - 6rpm');
+  plot(f, sqrt(pxsr_m), 'DisplayName', 'Slip-Ring - 6rpm');
+  plot(f, sqrt(pxof_m), 'DisplayName', 'OFF');
+  hold off;
+  set(gca, 'xscale', 'log');
+  set(gca, 'yscale', 'log');
+  xlabel('Frequency [Hz]'); ylabel('ASD of the measured Voltage $\left[\frac{V}{\sqrt{Hz}}\right]$')
+  legend('Location', 'southwest');
+  xlim([0.1, 500]);
+#+end_src
+
+#+NAME: fig:sr_sp_psd_marble_compare
+#+HEADER: :tangle no :exports results :results value raw replace :noweb yes
+#+begin_src matlab :var filepath="figs/sr_sp_psd_marble_compare.pdf" :var figsize="full-tall" :post pdf2svg(file=*this*, ext="png")
+  <<plt-matlab>>
+#+end_src
+
+#+NAME: fig:sr_sp_psd_marble_compare
+#+CAPTION: Comparison of the ASD of the measured voltage from the Geophone on the marble
+#+RESULTS: fig:sr_sp_psd_marble_compare
+[[file:figs/sr_sp_psd_marble_compare.png]]
+
+#+begin_src matlab :results none
+  figure;
+  hold on;
+  plot(f, sqrt(pxsp_s), 'DisplayName', 'Spindle - 6rpm');
+  plot(f, sqrt(pxsr_s), 'DisplayName', 'Slip-Ring - 6rpm');
+  plot(f, sqrt(pxof_s), 'DisplayName', 'OFF');
+  hold off;
+  set(gca, 'xscale', 'log');
+  set(gca, 'yscale', 'log');
+  xlabel('Frequency [Hz]'); ylabel('ASD of the measured Voltage $\left[\frac{V}{\sqrt{Hz}}\right]$')
+  legend('Location', 'southwest');
+  xlim([0.1, 500]);
+#+end_src
+
+#+NAME: fig:sr_sp_psd_sample_compare
+#+HEADER: :tangle no :exports results :results value raw replace :noweb yes
+#+begin_src matlab :var filepath="figs/sr_sp_psd_sample_compare.pdf" :var figsize="full-tall" :post pdf2svg(file=*this*, ext="png")
+  <<plt-matlab>>
+#+end_src
+
+#+NAME: fig:sr_sp_psd_sample_compare
+#+CAPTION: Comparison of the ASD of the measured voltage from the Geophone at the sample location
+#+RESULTS: fig:sr_sp_psd_sample_compare
+[[file:figs/sr_sp_psd_sample_compare.png]]
+
+** Conclusion
+#+begin_important
+  The slip-ring rotation induces almost no vibrations on the marble, and only a little vibrations on the sample above 100Hz.
+
+  The spindle rotation induces a lot of vibrations of the sample as well as on the granite.
+  There is a huge peak at 24Hz on the sample vibration but not on the granite vibration.
+#+end_important

slip-ring-spindle-vibrations/matlab/spindle_slip_ring_vibrations.m

@@ -0,0 +1,107 @@
+%% Clear Workspace and Close figures
+clear; close all; clc;
+
+%% Intialize Laplace variable
+s = zpk('s');
+
+% Load data
+
+of = load('mat/data_024.mat', 'data'); of = of.data;
+sr = load('mat/data_025.mat', 'data'); sr = sr.data;
+sp = load('mat/data_026.mat', 'data'); sp = sp.data;
+
+% Time domain plots
+
+figure;
+hold on;
+plot(sp(:, 3), sp(:, 1), 'DisplayName', 'Spindle - 6rpm');
+plot(sr(:, 3), sr(:, 1), 'DisplayName', 'Slip-Ring - 6rpm');
+plot(of(:, 3), of(:, 1), 'DisplayName', 'OFF');
+hold off;
+xlabel('Time [s]'); ylabel('Voltage [V]');
+xlim([0, 100]); ylim([-10 10]);
+legend('Location', 'northeast');
+
+
+
+% #+NAME: fig:slip_ring_spindle_marble_time
+% #+CAPTION: Measurement of the geophone located on the marble - Time domain
+% #+RESULTS: fig:slip_ring_spindle_marble_time
+% [[file:figs/slip_ring_spindle_marble_time.png]]
+
+
+figure;
+hold on;
+plot(sp(:, 3), sp(:, 2), 'DisplayName', 'Spindle and Slip-Ring');
+plot(sr(:, 3), sr(:, 2), 'DisplayName', 'Only Slip-Ring');
+plot(of(:, 3), of(:, 2), 'DisplayName', 'OFF');
+hold off;
+xlabel('Time [s]'); ylabel('Voltage [V]');
+xlim([0, 100]); ylim([-10 10]);
+legend('Location', 'northeast');
+
+% Frequency Domain
+% We first compute some parameters that will be used for the PSD computation.
+
+dt = of(2, 3)-of(1, 3);
+
+Fs = 1/dt; % [Hz]
+
+win = hanning(ceil(10*Fs));
+
+
+
+% Then we compute the Power Spectral Density using =pwelch= function.
+
+% First for the geophone located on the marble
+
+[pxof_m, f] = pwelch(of(:, 1), win, [], [], Fs);
+[pxsr_m, ~] = pwelch(sr(:, 1), win, [], [], Fs);
+[pxsp_m, ~] = pwelch(sp(:, 1), win, [], [], Fs);
+
+
+
+% And for the geophone located at the sample position.
+
+[pxof_s, f] = pwelch(of(:, 2), win, [], [], Fs);
+[pxsr_s, ~] = pwelch(sr(:, 2), win, [], [], Fs);
+[pxsp_s, ~] = pwelch(sp(:, 2), win, [], [], Fs);
+
+
+
+% And we plot the ASD of the measured signals:
+% - figure [[fig:sr_sp_psd_marble_compare]] for the geophone located on the marble
+% - figure [[fig:sr_sp_psd_sample_compare]] for the geophone at the sample position
+
+
+figure;
+hold on;
+plot(f, sqrt(pxsp_m), 'DisplayName', 'Spindle - 6rpm');
+plot(f, sqrt(pxsr_m), 'DisplayName', 'Slip-Ring - 6rpm');
+plot(f, sqrt(pxof_m), 'DisplayName', 'OFF');
+hold off;
+set(gca, 'xscale', 'log');
+set(gca, 'yscale', 'log');
+xlabel('Frequency [Hz]'); ylabel('ASD of the measured Voltage $\left[\frac{V}{\sqrt{Hz}}\right]$')
+legend('Location', 'southwest');
+xlim([0.1, 500]);
+
+
+
+% #+NAME: fig:sr_sp_psd_marble_compare
+% #+CAPTION: Comparison of the ASD of the measured voltage from the Geophone on the marble
+% #+RESULTS: fig:sr_sp_psd_marble_compare
+% [[file:figs/sr_sp_psd_marble_compare.png]]
+
+
+figure;
+hold on;
+plot(f, sqrt(pxsp_s), 'DisplayName', 'Spindle - 6rpm');
+plot(f, sqrt(pxsr_s), 'DisplayName', 'Slip-Ring - 6rpm');
+plot(f, sqrt(pxof_s), 'DisplayName', 'OFF');
+hold off;
+set(gca, 'xscale', 'log');
+set(gca, 'yscale', 'log');
+xlabel('Frequency [Hz]'); ylabel('ASD of the measured Voltage $\left[\frac{V}{\sqrt{Hz}}\right]$')
+legend('Location', 'southwest');
+xlim([0.1, 500]);