Update analysis: take into account the sensitivity of the geophone

2018-01-12 - Marc/index.org

@@ -76,49 +76,61 @@ The structure is excited using an *instrumented hammer* with impacts on
   <<matlab-init>>
 #+end_src
 
-Data is scaled and integrated one time to go from velocity to displacement.
+The Geophone sensitivity is defined below:
+#+begin_src matlab :results none
+  w0 = 4.5*2*pi; % [rad/s]
+  ksi = 0.38;
+  G0 = 31.3; % [V/(m/s)]
+  G = G0*(s/w0)^2/((s/w0)^2 + 2*ksi*(s/w0) + 1); % [V/(m/s)]
+#+end_src
+
+We then:
+- load the data
+- add a minus sign when needed
+- integrate the signal to have displacement instead of velocity
+- scaled with the sensitivity of the Geophone
 #+begin_src matlab :exports code :results none
   load('./raw_data/freq_frf.mat') % freq_frf
 
   w = j*2*pi*freq_frf; % j.omega in [rad/s]
 
-  scale_factor = 1;
+  scaling = squeeze(freqresp(G, 2*pi*freq_frf))/G0;
 
   load('./raw_data/frf_marble_x.mat') % ReIm1
   frf_marble_x = zeros(size(ReIm1, 1), 3);
-  frf_marble_x(:, 1) = -scale_factor*ReIm1(:, 2)./w; % marble_x
-  frf_marble_x(:, 2) = -scale_factor*ReIm1(:, 3)./w; % tilt_x
-  frf_marble_x(:, 3) = -scale_factor*ReIm1(:, 4)./w; % hexa_x
+  frf_marble_x(:, 1) = -ReIm1(:, 2)./w./scaling; % marble_x
+  frf_marble_x(:, 2) = -ReIm1(:, 3)./w./scaling; % tilt_x
+  frf_marble_x(:, 3) = -ReIm1(:, 4)./w./scaling; % hexa_x
 
   load('./raw_data/frf_hexa_x.mat') % ReIm2
   frf_hexa_x = zeros(size(ReIm2, 1), 3);
-  frf_hexa_x(:, 1) = -scale_factor*ReIm2(:, 2)./w; % marble_x
-  frf_hexa_x(:, 2) = -scale_factor*ReIm2(:, 3)./w; % tilt_x
-  frf_hexa_x(:, 3) = -scale_factor*ReIm2(:, 4)./w; % hexa_x
+  frf_hexa_x(:, 1) = -ReIm2(:, 2)./w./scaling; % marble_x
+  frf_hexa_x(:, 2) = -ReIm2(:, 3)./w./scaling; % tilt_x
+  frf_hexa_x(:, 3) = -ReIm2(:, 4)./w./scaling; % hexa_x
 
   load('./raw_data/frf_marble_y.mat') % ReIm3
   frf_marble_y = zeros(size(ReIm3, 1), 3);
-  frf_marble_y(:, 1) = -scale_factor*ReIm3(:, 2)./w; % marble_y
-  frf_marble_y(:, 2) = -scale_factor*ReIm3(:, 3)./w; % tilt_y
-  frf_marble_y(:, 3) = -scale_factor*ReIm3(:, 4)./w; % hexa_y
+  frf_marble_y(:, 1) = -ReIm3(:, 2)./w./scaling; % marble_y
+  frf_marble_y(:, 2) = -ReIm3(:, 3)./w./scaling; % tilt_y
+  frf_marble_y(:, 3) = -ReIm3(:, 4)./w./scaling; % hexa_y
 
   load('./raw_data/frf_hexa_y.mat') % ReIm4
   frf_hexa_y = zeros(size(ReIm4, 1), 3);
-  frf_hexa_y(:, 1) = scale_factor*ReIm4(:, 2)./w; % marble_y
-  frf_hexa_y(:, 2) = scale_factor*ReIm4(:, 3)./w; % tilt_y
-  frf_hexa_y(:, 3) = scale_factor*ReIm4(:, 4)./w; % hexa_y
+  frf_hexa_y(:, 1) = ReIm4(:, 2)./w./scaling; % marble_y
+  frf_hexa_y(:, 2) = ReIm4(:, 3)./w./scaling; % tilt_y
+  frf_hexa_y(:, 3) = ReIm4(:, 4)./w./scaling; % hexa_y
 
   load('./raw_data/frf_marble_z.mat') % ReIm5
   frf_marble_z = zeros(size(ReIm5, 1), 3);
-  frf_marble_z(:, 1) = scale_factor*ReIm5(:, 2)./w; % marble_z
-  frf_marble_z(:, 2) = scale_factor*ReIm5(:, 3)./w; % tilt_z
-  frf_marble_z(:, 3) = scale_factor*ReIm5(:, 4)./w; % hexa_z
+  frf_marble_z(:, 1) = ReIm5(:, 2)./w./scaling; % marble_z
+  frf_marble_z(:, 2) = ReIm5(:, 3)./w./scaling; % tilt_z
+  frf_marble_z(:, 3) = ReIm5(:, 4)./w./scaling; % hexa_z
 
   load('./raw_data/frf_hexa_z.mat') % ReIm6
   frf_hexa_z = zeros(size(ReIm6, 1), 3);
-  frf_hexa_z(:, 1) = scale_factor*ReIm6(:, 2)./w; % marble_z
-  frf_hexa_z(:, 2) = scale_factor*ReIm6(:, 3)./w; % tilt_z
-  frf_hexa_z(:, 3) = scale_factor*ReIm6(:, 4)./w; % hexa_z
+  frf_hexa_z(:, 1) = ReIm6(:, 2)./w./scaling; % marble_z
+  frf_hexa_z(:, 2) = ReIm6(:, 3)./w./scaling; % tilt_z
+  frf_hexa_z(:, 3) = ReIm6(:, 4)./w./scaling; % hexa_z
 #+end_src
 
 #+begin_src matlab :exports code :results none
@@ -159,6 +171,24 @@ Data is scaled and integrated one time to go from velocity to displacement.
   coh_hexa_z(:, 3) = coh6(:, 4); % hexa_z
 #+end_src
 
+Finally, we save the processed data.
+#+begin_src matlab :results none
+  save('./data/id31_microstation_2018_01_12_frf.mat', ...
+         'frf_marble_x', ...
+         'frf_marble_y', ...
+         'frf_marble_z', ...
+         'frf_hexa_x', ...
+         'frf_hexa_y', ...
+         'frf_hexa_z');
+  save('./data/id31_microstation_2018_01_12_frf.mat', ...
+         'coh_marble_x', ...
+         'coh_marble_y', ...
+         'coh_marble_z', ...
+         'coh_hexa_x', ...
+         'coh_hexa_y', ...
+         'coh_hexa_z');
+#+end_src
+
 ** X-direction FRF
 #+begin_src matlab :exports none :results none
   figure;
@@ -169,7 +199,7 @@ Data is scaled and integrated one time to go from velocity to displacement.
   hold off;
   set(gca, 'Xscale', 'log'); set(gca, 'Yscale', 'log');
   xlabel('Frequency [Hz]'); ylabel('Displacement/Force [m/N]');
-  xlim([10, 200]); xticks([10, 20, 50, 100, 200]);
+  xlim([5, 200]); xticks([5, 10, 20, 50, 100, 200]);
   legend('Location', 'southwest');
 #+end_src
 
@@ -194,7 +224,7 @@ Data is scaled and integrated one time to go from velocity to displacement.
   hold off;
   set(gca, 'Xscale', 'log'); set(gca, 'Yscale', 'log');
   xlabel('Frequency [Hz]'); ylabel('Displacement/Force [m/N]');
-  xlim([10, 200]); xticks([10, 20, 50, 100, 200]);
+  xlim([5, 200]); xticks([5, 10, 20, 50, 100, 200]);
   legend('Location', 'southwest');
 #+end_src
 
@@ -219,7 +249,7 @@ Data is scaled and integrated one time to go from velocity to displacement.
   hold off;
   set(gca, 'Xscale', 'log'); set(gca, 'Yscale', 'log');
   xlabel('Frequency [Hz]'); ylabel('Displacement/Force [m/N]');
-  xlim([10, 200]); xticks([10, 20, 50, 100, 200]);
+  xlim([5, 200]); xticks([5, 10, 20, 50, 100, 200]);
   legend('Location', 'southwest');
 #+end_src
 
@@ -243,7 +273,7 @@ Data is scaled and integrated one time to go from velocity to displacement.
   hold off;
   set(gca, 'Xscale', 'log'); set(gca, 'Yscale', 'log');
   xlabel('Frequency [Hz]'); ylabel('Displacement/Force [m/N]');
-  xlim([10, 200]); xticks([10, 20, 50, 100, 200]);
+  xlim([5, 200]); xticks([5, 10, 20, 50, 100, 200]);
   legend('Location', 'southwest');
 #+end_src
 
@@ -268,7 +298,7 @@ Data is scaled and integrated one time to go from velocity to displacement.
   hold off;
   set(gca, 'Xscale', 'log'); set(gca, 'Yscale', 'log');
   xlabel('Frequency [Hz]'); ylabel('Displacement/Force [m/N]');
-  xlim([10, 200]); xticks([10, 20, 50, 100, 200]);
+  xlim([5, 200]); xticks([5, 10, 20, 50, 100, 200]);
   legend('Location', 'southwest');
 #+end_src
 
@@ -292,7 +322,7 @@ Data is scaled and integrated one time to go from velocity to displacement.
   hold off;
   set(gca, 'Xscale', 'log'); set(gca, 'Yscale', 'log');
   xlabel('Frequency [Hz]'); ylabel('Displacement/Force [m/N]');
-  xlim([10, 200]); xticks([10, 20, 50, 100, 200]);
+  xlim([5, 200]); xticks([5, 10, 20, 50, 100, 200]);
   legend('Location', 'southwest');
 #+end_src
 

actuators-sensors/index.org

@@ -187,6 +187,9 @@ Its bode plot is shown on figure [[fig:L4C_bode_plot]].
 #+RESULTS: fig:L4C_bode_plot
 [[file:figs/L4C_bode_plot.png]]
 
+*** L-22
+- https://www.passcal.nmt.edu/content/instrumentation/sensors/short-period-sensors/l-22-sp-sensor
+
 ** Accelerometers
 *** Pieozoelectric acc. 356b18 - 3 axis
 - https://www.pcbpiezotronics.fr/produit/accelerometres/356b18/