nass-micro-station-measurem.../micro-station-compliance/index.org

20 KiB

Compliance Measurement of the Micro Station

Setup

Position of inertial sensors on top of the micro-hexapod

Orientation is relative to the frame determined by the X-ray

Num Position Orientation Sensibility Channels
1 [0, +A, 0] [x, y, z] 1V/g 1-3
2 [-B, 0, 0] [x, y, z] 1V/g 4-6
3 [0, -A, 0] [x, y, z] 0.1V/g 7-9
4 [+B, 0, 0] [x, y, z] 1V/g 10-12

Instrumented Hammer:

  • Channel 13
  • Sensibility: 230 uV/N
Acc Number Dir Channel Number
1 x 1
1 y 2
1 z 3
2 x 4
2 y 5
2 z 6
3 x 7
3 y 8
3 z 9
4 x 10
4 y 11
4 z 12
Hammer 13

From the acceleration measurement of the 4 accelerometers, we can compute the translations and rotations:

Formula
$D_x$ (1x + 2x + 3x + 4x)/4
$D_y$ (1y + 2y + 3y + 4y)/4
$D_z$ (1z + 2z + 3z + 4z)/4
$R_x$ (1z - 3z)/A
$R_y$ (2z - 4z)/B
$R_z$ (3x - 1x)/A, (4y - 2y)/B
Formula
$D_x$ (1 + 4 + 7 + 10)/4
$D_y$ (2 + 5 + 8 + 11)/4
$D_z$ (3 + 6 + 9 + 12)/4
$R_x$ (1 - 9)/A
$R_y$ (6 - 12)/B
$R_z$ (7 - 1)/A, (11 - 5)/B

Hammer blow position/orientation

Num Direction Position
1 -Y [0, +A, 0]
2 -Z [0, +A, 0]
3 X [-B, 0, 0]
4 -Z [-B, 0, 0]
5 Y [0, -A, 0]
6 -Z [0, -A, 0]
7 -X [+B, 0, 0]
8 -Z [+B, 0, 0]
9 -X [0, -A, 0]
10 -X [0, +A, 0]

From hammer blows to pure forces / torques:

Formula Alternative
$F_x$ +3 -7
$F_y$ -1 +5
$F_z$ -(2 + 6)/2 -(4 + 8)/2
$M_x$ A/2*(2 - 6)
$M_y$ B/2*(8 - 4)
$M_z$ A/2*(10 - 9)

Results

Load Data

  m1 = load('data/Measurement1.mat');
  m2 = load('data/Measurement2.mat');
  m3 = load('data/Measurement3.mat');
  m4 = load('data/Measurement4.mat');
  m5 = load('data/Measurement5.mat');
  m6 = load('data/Measurement6.mat');
  m7 = load('data/Measurement7.mat');
  m8 = load('data/Measurement8.mat');
  m9 = load('data/Measurement9.mat');
  m10 = load('data/Measurement10.mat');

Compute Transfer Functions

  freqs = m3.FFT1_H1_1_13_X_Val;
  w = 2*pi*freqs';

  A = 0.14;
  B = 0.14;
  G = zeros(6,6,length(freqs));

  % Fx
  G(1,1,:) = (m3.FFT1_H1_1_13_Y_ReIm + m3.FFT1_H1_4_13_Y_ReIm + m3.FFT1_H1_7_13_Y_ReIm + m3.FFT1_H1_10_13_Y_ReIm)./4;
  G(2,1,:) = (m3.FFT1_H1_2_13_Y_ReIm + m3.FFT1_H1_5_13_Y_ReIm + m3.FFT1_H1_8_13_Y_ReIm + m3.FFT1_H1_11_13_Y_ReIm)./4;
  G(3,1,:) = (m3.FFT1_H1_3_13_Y_ReIm + m3.FFT1_H1_6_13_Y_ReIm + m3.FFT1_H1_9_13_Y_ReIm + m3.FFT1_H1_12_13_Y_ReIm)./4;
  G(4,1,:) = (m3.FFT1_H1_1_13_Y_ReIm - m3.FFT1_H1_9_13_Y_ReIm )./A;
  G(5,1,:) = (m3.FFT1_H1_6_13_Y_ReIm - m3.FFT1_H1_12_13_Y_ReIm)./B;
  G(6,1,:) = (m3.FFT1_H1_7_13_Y_ReIm - m3.FFT1_H1_1_13_Y_ReIm )./A;

  % Fy
  G(1,2,:) = -(m1.FFT1_H1_2_13_Y_ReIm + m1.FFT1_H1_5_13_Y_ReIm + m1.FFT1_H1_8_13_Y_ReIm + m1.FFT1_H1_11_13_Y_ReIm)./4;
  G(2,2,:) = -(m1.FFT1_H1_2_13_Y_ReIm + m1.FFT1_H1_5_13_Y_ReIm + m1.FFT1_H1_8_13_Y_ReIm + m1.FFT1_H1_11_13_Y_ReIm)./4;
  G(3,2,:) = -(m1.FFT1_H1_3_13_Y_ReIm + m1.FFT1_H1_6_13_Y_ReIm + m1.FFT1_H1_9_13_Y_ReIm + m1.FFT1_H1_12_13_Y_ReIm)./4;
  G(4,2,:) = -(m1.FFT1_H1_1_13_Y_ReIm - m1.FFT1_H1_9_13_Y_ReIm )./A;
  G(5,2,:) = -(m1.FFT1_H1_6_13_Y_ReIm - m1.FFT1_H1_12_13_Y_ReIm)./B;
  G(6,2,:) = -(m1.FFT1_H1_7_13_Y_ReIm - m1.FFT1_H1_1_13_Y_ReIm )./A;


  % Fz
  G(1,3,:) = -1/2./(1./(m2.FFT1_H1_1_13_Y_ReIm + m2.FFT1_H1_4_13_Y_ReIm + m2.FFT1_H1_7_13_Y_ReIm + m2.FFT1_H1_10_13_Y_ReIm) + ...
                    1./(m6.FFT1_H1_1_13_Y_ReIm + m6.FFT1_H1_4_13_Y_ReIm + m6.FFT1_H1_7_13_Y_ReIm + m6.FFT1_H1_10_13_Y_ReIm));
  G(2,3,:) = -1/2./(1./(m2.FFT1_H1_2_13_Y_ReIm + m2.FFT1_H1_5_13_Y_ReIm + m2.FFT1_H1_8_13_Y_ReIm + m2.FFT1_H1_11_13_Y_ReIm) + ...
                    1./(m6.FFT1_H1_2_13_Y_ReIm + m6.FFT1_H1_5_13_Y_ReIm + m6.FFT1_H1_8_13_Y_ReIm + m6.FFT1_H1_11_13_Y_ReIm));
  G(3,3,:) = -1/2./(1./(m2.FFT1_H1_3_13_Y_ReIm + m2.FFT1_H1_6_13_Y_ReIm + m2.FFT1_H1_9_13_Y_ReIm + m2.FFT1_H1_12_13_Y_ReIm) + ...
                    1./(m6.FFT1_H1_3_13_Y_ReIm + m6.FFT1_H1_6_13_Y_ReIm + m6.FFT1_H1_9_13_Y_ReIm + m6.FFT1_H1_12_13_Y_ReIm));
  G(4,3,:) = -2/A./(1./(m2.FFT1_H1_1_13_Y_ReIm - m2.FFT1_H1_9_13_Y_ReIm) + ...
                    1./(m6.FFT1_H1_1_13_Y_ReIm - m6.FFT1_H1_9_13_Y_ReIm));
  G(5,3,:) = -2/B./(1./(m2.FFT1_H1_6_13_Y_ReIm - m2.FFT1_H1_12_13_Y_ReIm) + ...
                    1./(m6.FFT1_H1_6_13_Y_ReIm - m6.FFT1_H1_12_13_Y_ReIm));
  G(6,3,:) = -2/A./(1./(m2.FFT1_H1_7_13_Y_ReIm - m2.FFT1_H1_1_13_Y_ReIm) + ...
                    1./(m6.FFT1_H1_7_13_Y_ReIm - m6.FFT1_H1_1_13_Y_ReIm));

  % Mx
  G(1,4,:) = 1/A/2./(1./(m2.FFT1_H1_1_13_Y_ReIm + m2.FFT1_H1_4_13_Y_ReIm + m2.FFT1_H1_7_13_Y_ReIm + m2.FFT1_H1_10_13_Y_ReIm) - ...
                   1./(m6.FFT1_H1_1_13_Y_ReIm + m6.FFT1_H1_4_13_Y_ReIm + m6.FFT1_H1_7_13_Y_ReIm + m6.FFT1_H1_10_13_Y_ReIm));
  G(2,4,:) = 1/A/2./(1./(m2.FFT1_H1_2_13_Y_ReIm + m2.FFT1_H1_5_13_Y_ReIm + m2.FFT1_H1_8_13_Y_ReIm + m2.FFT1_H1_11_13_Y_ReIm) - ...
                   1./(m6.FFT1_H1_2_13_Y_ReIm + m6.FFT1_H1_5_13_Y_ReIm + m6.FFT1_H1_8_13_Y_ReIm + m6.FFT1_H1_11_13_Y_ReIm));
  G(3,4,:) = 1/A/2./(1./(m2.FFT1_H1_3_13_Y_ReIm + m2.FFT1_H1_6_13_Y_ReIm + m2.FFT1_H1_9_13_Y_ReIm + m2.FFT1_H1_12_13_Y_ReIm) - ...
                   1./(m6.FFT1_H1_3_13_Y_ReIm + m6.FFT1_H1_6_13_Y_ReIm + m6.FFT1_H1_9_13_Y_ReIm + m6.FFT1_H1_12_13_Y_ReIm));
  G(4,4,:) = 1/A^2*2./(1./(m2.FFT1_H1_1_13_Y_ReIm - m2.FFT1_H1_9_13_Y_ReIm) - ...
                 1./(m6.FFT1_H1_1_13_Y_ReIm - m6.FFT1_H1_9_13_Y_ReIm));
  G(5,4,:) = 2/A/B./(1./(m2.FFT1_H1_6_13_Y_ReIm - m2.FFT1_H1_12_13_Y_ReIm) - ...
                 1./(m6.FFT1_H1_6_13_Y_ReIm - m6.FFT1_H1_12_13_Y_ReIm));
  G(6,4,:) = 1/A^2*2./(1./(m2.FFT1_H1_7_13_Y_ReIm - m2.FFT1_H1_1_13_Y_ReIm) - ...
                 1./(m6.FFT1_H1_7_13_Y_ReIm - m6.FFT1_H1_1_13_Y_ReIm));

  % My
  G(1,5,:) = 1/B/2./(1./(m8.FFT1_H1_1_13_Y_ReIm + m8.FFT1_H1_4_13_Y_ReIm + m8.FFT1_H1_7_13_Y_ReIm + m8.FFT1_H1_10_13_Y_ReIm) - ...
                   1./(m4.FFT1_H1_1_13_Y_ReIm + m4.FFT1_H1_4_13_Y_ReIm + m4.FFT1_H1_7_13_Y_ReIm + m4.FFT1_H1_10_13_Y_ReIm));
  G(2,5,:) = 1/B/2./(1./(m8.FFT1_H1_2_13_Y_ReIm + m8.FFT1_H1_5_13_Y_ReIm + m8.FFT1_H1_8_13_Y_ReIm + m8.FFT1_H1_11_13_Y_ReIm) - ...
                   1./(m4.FFT1_H1_2_13_Y_ReIm + m4.FFT1_H1_5_13_Y_ReIm + m4.FFT1_H1_8_13_Y_ReIm + m4.FFT1_H1_11_13_Y_ReIm));
  G(3,5,:) = 1/B/2./(1./(m8.FFT1_H1_3_13_Y_ReIm + m8.FFT1_H1_6_13_Y_ReIm + m8.FFT1_H1_9_13_Y_ReIm + m8.FFT1_H1_12_13_Y_ReIm) - ...
                   1./(m4.FFT1_H1_3_13_Y_ReIm + m4.FFT1_H1_6_13_Y_ReIm + m4.FFT1_H1_9_13_Y_ReIm + m4.FFT1_H1_12_13_Y_ReIm));
  G(4,5,:) = 2/B/A./(1./(m8.FFT1_H1_1_13_Y_ReIm - m8.FFT1_H1_9_13_Y_ReIm) - ...
                     1./(m4.FFT1_H1_1_13_Y_ReIm - m4.FFT1_H1_9_13_Y_ReIm));
  G(5,5,:) = 1/B^2*2./(1./(m8.FFT1_H1_6_13_Y_ReIm - m8.FFT1_H1_12_13_Y_ReIm) - ...
                 1./(m4.FFT1_H1_6_13_Y_ReIm - m4.FFT1_H1_12_13_Y_ReIm));
  G(6,5,:) = 2/B/A./(1./(m8.FFT1_H1_7_13_Y_ReIm - m8.FFT1_H1_1_13_Y_ReIm) - ...
                     1./(m4.FFT1_H1_7_13_Y_ReIm - m4.FFT1_H1_1_13_Y_ReIm));

  % Mz
  G(1,6,:) = 1/A/2./(1./(m10.FFT1_H1_1_13_Y_ReIm + m10.FFT1_H1_4_13_Y_ReIm + m10.FFT1_H1_7_13_Y_ReIm + m10.FFT1_H1_10_13_Y_ReIm) - ...
                   1./(m9.FFT1_H1_1_13_Y_ReIm + m9.FFT1_H1_4_13_Y_ReIm + m9.FFT1_H1_7_13_Y_ReIm + m9.FFT1_H1_10_13_Y_ReIm));
  G(2,6,:) = 1/A/2./(1./(m10.FFT1_H1_2_13_Y_ReIm + m10.FFT1_H1_5_13_Y_ReIm + m10.FFT1_H1_8_13_Y_ReIm + m10.FFT1_H1_11_13_Y_ReIm) - ...
                   1./(m9.FFT1_H1_2_13_Y_ReIm + m9.FFT1_H1_5_13_Y_ReIm + m9.FFT1_H1_8_13_Y_ReIm + m9.FFT1_H1_11_13_Y_ReIm));
  G(3,6,:) = 1/A/2./(1./(m10.FFT1_H1_3_13_Y_ReIm + m10.FFT1_H1_6_13_Y_ReIm + m10.FFT1_H1_9_13_Y_ReIm + m10.FFT1_H1_12_13_Y_ReIm) - ...
                   1./(m9.FFT1_H1_3_13_Y_ReIm + m9.FFT1_H1_6_13_Y_ReIm + m9.FFT1_H1_9_13_Y_ReIm + m9.FFT1_H1_12_13_Y_ReIm));
  G(4,6,:) = 1/A^2*2./(1./(m10.FFT1_H1_1_13_Y_ReIm - m10.FFT1_H1_9_13_Y_ReIm) - ...
                 1./(m9.FFT1_H1_1_13_Y_ReIm - m9.FFT1_H1_9_13_Y_ReIm));
  G(5,6,:) = 2*A/B./(1./(m10.FFT1_H1_6_13_Y_ReIm - m10.FFT1_H1_12_13_Y_ReIm) - ...
                     1./(m9.FFT1_H1_6_13_Y_ReIm - m9.FFT1_H1_12_13_Y_ReIm));
  G(6,6,:) = 1/A^2*2./(1./(m10.FFT1_H1_7_13_Y_ReIm - m10.FFT1_H1_1_13_Y_ReIm) - ...
                 1./(m9.FFT1_H1_7_13_Y_ReIm - m9.FFT1_H1_1_13_Y_ReIm));

Diagonal Dynamics

  figure;
  ax1 = subplot(2,1,1);
  hold on;
  plot(freqs, abs(squeeze(G(1,1,:))./(-w.^2)), '.')
  plot(freqs, abs(squeeze(G(2,2,:))./(-w.^2)), '.')
  plot(freqs, abs(squeeze(G(3,3,:))./(-w.^2)), '.')
  hold off;
  set(gca, 'XScale', 'log'); set(gca, 'YScale', 'log');
  ylabel('Magnitude [m/N]'); set(gca, 'XTickLabel',[]);
  ylim([1e-9, 2e-6]);

  ax2 = subplot(2,1,2);
  hold on;
  plot(freqs, 180/pi*angle(squeeze(G(1,1,:))./(-w.^2)), '.', 'DisplayName', '$D_x/F_x$')
  plot(freqs, 180/pi*angle(squeeze(G(2,2,:))./(-w.^2)), '.', 'DisplayName', '$D_y/F_y$')
  plot(freqs, 180/pi*angle(squeeze(G(3,3,:))./(-w.^2)), '.', 'DisplayName', '$D_z/F_z$')
  hold off;
  set(gca, 'XScale', 'log'); set(gca, 'YScale', 'lin');
  xlabel('Freqency [Hz]'); ylabel('Phase [deg]');
  ylim([-180, 180]);
  yticks([-180, -90, 0, 90, 180]);
  legend('location', 'southwest');

  linkaxes([ax1,ax2],'x');
  xlim([30, 300]);

/tdehaeze/nass-micro-station-measurements/media/commit/5f59f13f9a96a17ab09fc92bdea5829d2649be30/micro-station-compliance/figs/compliance_diagonal_translations.png

Dynamics from Forces to Translations
  figure;
  ax1 = subplot(2,1,1);
  hold on;
  plot(freqs, abs(squeeze(G(4,4,:))./(-w.^2)), '.')
  plot(freqs, abs(squeeze(G(5,5,:))./(-w.^2)), '.')
  plot(freqs, abs(squeeze(G(6,6,:))./(-w.^2)), '.')
  hold off;
  set(gca, 'XScale', 'log'); set(gca, 'YScale', 'log');
  ylabel('Magnitude [rad/Nm]'); set(gca, 'XTickLabel',[]);
  ylim([1e-9, 2e-6]);

  ax2 = subplot(2,1,2);
  hold on;
  plot(freqs, 180/pi*angle(squeeze(G(4,4,:))./(-w.^2)), '.', 'DisplayName', '$R_x/M_x$')
  plot(freqs, 180/pi*angle(squeeze(G(5,5,:))./(-w.^2)), '.', 'DisplayName', '$R_y/M_y$')
  plot(freqs, 180/pi*angle(squeeze(G(6,6,:))./(-w.^2)), '.', 'DisplayName', '$R_z/M_z$')
  hold off;
  set(gca, 'XScale', 'log'); set(gca, 'YScale', 'lin');
  xlabel('Freqency [Hz]'); ylabel('Phase [deg]');
  ylim([-180, 180]);
  yticks([-180, -90, 0, 90, 180]);
  legend('location', 'southwest');

  linkaxes([ax1,ax2],'x');
  xlim([30, 300]);

/tdehaeze/nass-micro-station-measurements/media/commit/5f59f13f9a96a17ab09fc92bdea5829d2649be30/micro-station-compliance/figs/compliance_diagonal_rotations.png

Dynamics from Torques to Rotations
Stiffness Unit
$K_x$ 1e7 [N/m]
$K_y$ 1e7 [N/m]
$K_z$ 2e8 [N/m]
$K_{R_x}$ ? [Nm/rad]
$K_{R_y}$ 1.8e7 [Nm/rad]
$K_{R_z}$ 1e7 [Nm/rad]

Compare with Model

  load('./mat/model.mat', 'Gm');
  figure;
  ax1 = subplot(2,1,1);
  hold on;
  plot(freqs, abs(squeeze(G(1,1,:))./(-w.^2)), '.')
  plot(freqs, abs(squeeze(G(2,2,:))./(-w.^2)), '.')
  plot(freqs, abs(squeeze(G(3,3,:))./(-w.^2)), '.')
  set(gca,'ColorOrderIndex',1);
  plot(freqs, abs(squeeze(freqresp(Gm(1,1,:), freqs, 'Hz'))), '-')
  plot(freqs, abs(squeeze(freqresp(Gm(2,2,:), freqs, 'Hz'))), '-')
  plot(freqs, abs(squeeze(freqresp(Gm(3,3,:), freqs, 'Hz'))), '-')
  hold off;
  set(gca, 'XScale', 'log'); set(gca, 'YScale', 'log');
  ylabel('Magnitude [m/N]'); set(gca, 'XTickLabel',[]);
  ylim([1e-9, 2e-6]);

  ax2 = subplot(2,1,2);
  hold on;
  plot(freqs, 180/pi*angle(squeeze(G(1,1,:))./(-w.^2)), '.', 'DisplayName', '$D_x/F_x$')
  plot(freqs, 180/pi*angle(squeeze(G(2,2,:))./(-w.^2)), '.', 'DisplayName', '$D_y/F_y$')
  plot(freqs, 180/pi*angle(squeeze(G(3,3,:))./(-w.^2)), '.', 'DisplayName', '$D_z/F_z$')
  set(gca,'ColorOrderIndex',1);
  plot(freqs, 180/pi*angle(squeeze(freqresp(Gm(1,1,:), freqs, 'Hz'))), '-', 'HandleVisibility', 'off')
  plot(freqs, 180/pi*angle(squeeze(freqresp(Gm(2,2,:), freqs, 'Hz'))), '-', 'HandleVisibility', 'off')
  plot(freqs, 180/pi*angle(squeeze(freqresp(Gm(3,3,:), freqs, 'Hz'))), '-', 'HandleVisibility', 'off')
  hold off;
  set(gca, 'XScale', 'log'); set(gca, 'YScale', 'lin');
  xlabel('Freqency [Hz]'); ylabel('Phase [deg]');
  ylim([-180, 180]);
  yticks([-180, -90, 0, 90, 180]);
  legend('location', 'southwest');

  linkaxes([ax1,ax2],'x');
  xlim([30, 300]);

/tdehaeze/nass-micro-station-measurements/media/commit/5f59f13f9a96a17ab09fc92bdea5829d2649be30/micro-station-compliance/figs/compliance_diagonal_translations_comp_model.png

Dynamics from Forces to Translations
  figure;
  ax1 = subplot(2,1,1);
  hold on;
  plot(freqs, abs(squeeze(G(4,4,:))./(-w.^2)), '.')
  plot(freqs, abs(squeeze(G(5,5,:))./(-w.^2)), '.')
  plot(freqs, abs(squeeze(G(6,6,:))./(-w.^2)), '.')
  set(gca,'ColorOrderIndex',1);
  plot(freqs, abs(squeeze(freqresp(Gm(4,4,:), freqs, 'Hz'))), '-')
  plot(freqs, abs(squeeze(freqresp(Gm(5,5,:), freqs, 'Hz'))), '-')
  plot(freqs, abs(squeeze(freqresp(Gm(6,6,:), freqs, 'Hz'))), '-')
  hold off;
  set(gca, 'XScale', 'log'); set(gca, 'YScale', 'log');
  ylabel('Magnitude [rad/Nm]'); set(gca, 'XTickLabel',[]);
  % ylim([1e-9, 2e-6]);

  ax2 = subplot(2,1,2);
  hold on;
  plot(freqs, 180/pi*angle(squeeze(G(4,4,:))./(-w.^2)), '.', 'DisplayName', '$R_x/M_x$')
  plot(freqs, 180/pi*angle(squeeze(G(5,5,:))./(-w.^2)), '.', 'DisplayName', '$R_y/M_y$')
  plot(freqs, 180/pi*angle(squeeze(G(6,6,:))./(-w.^2)), '.', 'DisplayName', '$R_z/M_z$')
  set(gca,'ColorOrderIndex',1);
  plot(freqs, 180/pi*angle(squeeze(freqresp(Gm(4,4,:), freqs, 'Hz'))), '-', 'HandleVisibility', 'off')
  plot(freqs, 180/pi*angle(squeeze(freqresp(Gm(5,5,:), freqs, 'Hz'))), '-', 'HandleVisibility', 'off')
  plot(freqs, 180/pi*angle(squeeze(freqresp(Gm(6,6,:), freqs, 'Hz'))), '-', 'HandleVisibility', 'off')
  hold off;
  set(gca, 'XScale', 'log'); set(gca, 'YScale', 'lin');
  xlabel('Freqency [Hz]'); ylabel('Phase [deg]');
  ylim([-180, 180]);
  yticks([-180, -90, 0, 90, 180]);
  legend('location', 'southwest');

  linkaxes([ax1,ax2],'x');
  xlim([30, 300]);

/tdehaeze/nass-micro-station-measurements/media/commit/5f59f13f9a96a17ab09fc92bdea5829d2649be30/micro-station-compliance/figs/compliance_diagonal_rotations_comp_model.png

Dynamics from Torques to Rotations
Stiffness Unit
$K_x$ 1e7 [N/m]
$K_y$ 1e7 [N/m]
$K_z$ 2e8 [N/m]
$K_{R_x}$ 5e7 [Nm/rad]
$K_{R_y}$ 3e7 [Nm/rad]
$K_{R_z}$ 2e7 [Nm/rad]

Coupling Dynamics

  figure;
  ax1 = subplot(2,1,1);
  hold on;
  plot(freqs, abs(squeeze(G(1,1,:))./(-w.^2)), '.')
  plot(freqs, abs(squeeze(G(2,1,:))./(-w.^2)), '.')
  plot(freqs, abs(squeeze(G(3,1,:))./(-w.^2)), '.')
  set(gca,'ColorOrderIndex',1);
  plot(freqs, abs(squeeze(freqresp(Gm(1,1,:), freqs, 'Hz'))), '-')
  plot(freqs, abs(squeeze(freqresp(Gm(2,1,:), freqs, 'Hz'))), '-')
  plot(freqs, abs(squeeze(freqresp(Gm(3,1,:), freqs, 'Hz'))), '-')
  hold off;
  set(gca, 'XScale', 'log'); set(gca, 'YScale', 'log');
  ylabel('Magnitude [m/N]'); set(gca, 'XTickLabel',[]);
  ylim([1e-9, 2e-6]);

  ax2 = subplot(2,1,2);
  hold on;
  plot(freqs, 180/pi*angle(squeeze(G(1,1,:))./(-w.^2)), '.', 'DisplayName', '$D_x/F_x$')
  plot(freqs, 180/pi*angle(squeeze(G(2,1,:))./(-w.^2)), '.', 'DisplayName', '$D_y/F_x$')
  plot(freqs, 180/pi*angle(squeeze(G(3,1,:))./(-w.^2)), '.', 'DisplayName', '$D_z/F_x$')
  set(gca,'ColorOrderIndex',1);
  plot(freqs, 180/pi*angle(squeeze(freqresp(Gm(1,1,:), freqs, 'Hz'))), '-', 'HandleVisibility', 'off')
  plot(freqs, 180/pi*angle(squeeze(freqresp(Gm(2,1,:), freqs, 'Hz'))), '-', 'HandleVisibility', 'off')
  plot(freqs, 180/pi*angle(squeeze(freqresp(Gm(3,1,:), freqs, 'Hz'))), '-', 'HandleVisibility', 'off')
  hold off;
  set(gca, 'XScale', 'log'); set(gca, 'YScale', 'lin');
  xlabel('Freqency [Hz]'); ylabel('Phase [deg]');
  ylim([-180, 180]);
  yticks([-180, -90, 0, 90, 180]);
  legend('location', 'southwest');

  linkaxes([ax1,ax2],'x');
  xlim([30, 300]);
  figure;
  ax1 = subplot(2,1,1);
  hold on;
  plot(freqs, abs(squeeze(G(5,1,:))./(-w.^2)), '.')
  plot(freqs, abs(squeeze(G(4,2,:))./(-w.^2)), '.')
  set(gca,'ColorOrderIndex',1);
  plot(freqs, abs(squeeze(freqresp(Gm(5,1,:), freqs, 'Hz'))), '-')
  plot(freqs, abs(squeeze(freqresp(Gm(4,2,:), freqs, 'Hz'))), '-')
  hold off;
  set(gca, 'XScale', 'log'); set(gca, 'YScale', 'log');
  ylabel('Magnitude [m/N]'); set(gca, 'XTickLabel',[]);
  ylim([1e-9, 2e-6]);

  ax2 = subplot(2,1,2);
  hold on;
  plot(freqs, 180/pi*angle(squeeze(G(5,1,:))./(-w.^2)), '.', 'DisplayName', '$R_y/F_x$')
  plot(freqs, 180/pi*angle(squeeze(G(4,2,:))./(-w.^2)), '.', 'DisplayName', '$R_x/F_y$')
  set(gca,'ColorOrderIndex',1);
  plot(freqs, 180/pi*angle(squeeze(freqresp(Gm(5,1,:), freqs, 'Hz'))), '-', 'HandleVisibility', 'off')
  plot(freqs, 180/pi*angle(squeeze(freqresp(Gm(4,2,:), freqs, 'Hz'))), '-', 'HandleVisibility', 'off')
  hold off;
  set(gca, 'XScale', 'log'); set(gca, 'YScale', 'lin');
  xlabel('Freqency [Hz]'); ylabel('Phase [deg]');
  ylim([-180, 180]);
  yticks([-180, -90, 0, 90, 180]);
  legend('location', 'southwest');

  linkaxes([ax1,ax2],'x');
  xlim([30, 300]);