218 lines
6.1 KiB
Mathematica
218 lines
6.1 KiB
Mathematica
|
%% Clear Workspace and Close figures
|
||
|
|
clear; close all; clc;
|
||
|
|
|
||
|
|
%% Intialize Laplace variable
|
||
|
|
s = zpk('s');
|
||
|
|
|
||
|
|
colors = colororder;
|
||
|
|
|
||
|
|
addpath('./mat/');
|
||
|
|
addpath('./src/');
|
||
|
|
|
||
|
|
%% Numnbers of the measured legs
|
||
|
|
leg_nums = [1 2 3 4 5];
|
||
|
|
|
||
|
|
%% First identification (low frequency noise)
|
||
|
|
leg_noise = {};
|
||
|
|
for i = 1:length(leg_nums)
|
||
|
|
leg_noise(i) = {load(sprintf('frf_data_leg_coder_%i_noise.mat', leg_nums(i)), 't', 'Va', 'Vs', 'de', 'da')};
|
||
|
|
end
|
||
|
|
|
||
|
|
%% Second identification (high frequency noise)
|
||
|
|
leg_noise_hf = {};
|
||
|
|
for i = 1:length(leg_nums)
|
||
|
|
leg_noise_hf(i) = {load(sprintf('frf_data_leg_coder_%i_noise_hf.mat', leg_nums(i)), 't', 'Va', 'Vs', 'de', 'da')};
|
||
|
|
end
|
||
|
|
|
||
|
|
%% Time vector
|
||
|
|
t = leg_noise{1}.t - leg_noise{1}.t(1) ; % Time vector [s]
|
||
|
|
|
||
|
|
%% Sampling
|
||
|
|
Ts = (t(end) - t(1))/(length(t)-1); % Sampling Time [s]
|
||
|
|
Fs = 1/Ts; % Sampling Frequency [Hz]
|
||
|
|
|
||
|
|
win = hanning(ceil(0.5*Fs)); % Hannning Windows
|
||
|
|
|
||
|
|
% Only used to have the frequency vector "f"
|
||
|
|
[~, f] = tfestimate(leg_noise{1}.Va, leg_noise{1}.de, win, [], [], 1/Ts);
|
||
|
|
i_lf = f <= 350;
|
||
|
|
i_hf = f > 350;
|
||
|
|
|
||
|
|
%% Coherence computation
|
||
|
|
coh_enc = zeros(length(f), length(leg_nums));
|
||
|
|
for i = 1:length(leg_nums)
|
||
|
|
[coh_lf, ~] = mscohere(leg_noise{i}.Va, leg_noise{i}.de, win, [], [], 1/Ts);
|
||
|
|
[coh_hf, ~] = mscohere(leg_noise_hf{i}.Va, leg_noise_hf{i}.de, win, [], [], 1/Ts);
|
||
|
|
coh_enc(:, i) = [coh_lf(i_lf); coh_hf(i_hf)];
|
||
|
|
end
|
||
|
|
|
||
|
|
%% Plot the coherence
|
||
|
|
figure;
|
||
|
|
hold on;
|
||
|
|
for i = 1:length(leg_nums)
|
||
|
|
plot(f, coh_enc(:, i));
|
||
|
|
end;
|
||
|
|
hold off;
|
||
|
|
set(gca, 'XScale', 'log'); set(gca, 'YScale', 'lin');
|
||
|
|
xlabel('Frequency [Hz]'); ylabel('Coherence [-]');
|
||
|
|
xlim([10, 2e3]); ylim([0, 1]);
|
||
|
|
|
||
|
|
%% Transfer function estimation
|
||
|
|
enc_frf = zeros(length(f), length(leg_nums));
|
||
|
|
|
||
|
|
for i = 1:length(leg_nums)
|
||
|
|
[frf_lf, ~] = tfestimate(leg_noise{i}.Va, leg_noise{i}.de, win, [], [], 1/Ts);
|
||
|
|
[frf_hf, ~] = tfestimate(leg_noise_hf{i}.Va, leg_noise_hf{i}.de, win, [], [], 1/Ts);
|
||
|
|
enc_frf(:, i) = [frf_lf(i_lf); frf_hf(i_hf)];
|
||
|
|
end
|
||
|
|
|
||
|
|
%% Bode plot of the FRF from Va to de
|
||
|
|
figure;
|
||
|
|
tiledlayout(3, 1, 'TileSpacing', 'None', 'Padding', 'None');
|
||
|
|
|
||
|
|
ax1 = nexttile([2,1]);
|
||
|
|
hold on;
|
||
|
|
for i = 1:length(leg_nums)
|
||
|
|
plot(f, abs(enc_frf(:, i)), ...
|
||
|
|
'DisplayName', sprintf('Leg %i', leg_nums(i)));
|
||
|
|
end
|
||
|
|
hold off;
|
||
|
|
set(gca, 'XScale', 'log'); set(gca, 'YScale', 'log');
|
||
|
|
ylabel('Amplitude $d_e/V_a$ [m/V]'); set(gca, 'XTickLabel',[]);
|
||
|
|
hold off;
|
||
|
|
legend('location', 'northeast', 'FontSize', 8, 'NumColumns', 2);
|
||
|
|
ylim([1e-8, 1e-3]);
|
||
|
|
|
||
|
|
ax2 = nexttile;
|
||
|
|
hold on;
|
||
|
|
for i = 1:length(leg_nums)
|
||
|
|
plot(f, 180/pi*angle(enc_frf(:, i)));
|
||
|
|
end
|
||
|
|
hold off;
|
||
|
|
set(gca, 'XScale', 'log'); set(gca, 'YScale', 'lin');
|
||
|
|
xlabel('Frequency [Hz]'); ylabel('Phase [deg]');
|
||
|
|
hold off;
|
||
|
|
yticks(-360:90:360); ylim([-180, 180]);
|
||
|
|
|
||
|
|
linkaxes([ax1,ax2],'x');
|
||
|
|
xlim([10, 2e3]);
|
||
|
|
|
||
|
|
%% Coherence computation
|
||
|
|
coh_int = zeros(length(f), length(leg_nums));
|
||
|
|
for i = 1:length(leg_nums)
|
||
|
|
[coh_lf, ~] = mscohere(leg_noise{i}.Va, leg_noise{i}.da, win, [], [], 1/Ts);
|
||
|
|
[coh_hf, ~] = mscohere(leg_noise_hf{i}.Va, leg_noise_hf{i}.da, win, [], [], 1/Ts);
|
||
|
|
coh_int(:, i) = [coh_lf(i_lf); coh_hf(i_hf)];
|
||
|
|
end
|
||
|
|
|
||
|
|
%% Plot coherence
|
||
|
|
figure;
|
||
|
|
hold on;
|
||
|
|
for i = 1:length(leg_nums)
|
||
|
|
plot(f, coh_int(:, i));
|
||
|
|
end;
|
||
|
|
hold off;
|
||
|
|
set(gca, 'XScale', 'log'); set(gca, 'YScale', 'lin');
|
||
|
|
xlabel('Frequency [Hz]'); ylabel('Coherence [-]');
|
||
|
|
xlim([10, 2e3]); ylim([0, 1]);
|
||
|
|
|
||
|
|
%% Transfer function estimation
|
||
|
|
int_frf = zeros(length(f), length(leg_nums));
|
||
|
|
for i = 1:length(leg_nums)
|
||
|
|
[frf_lf, ~] = tfestimate(leg_noise{i}.Va, leg_noise{i}.da, win, [], [], 1/Ts);
|
||
|
|
[frf_hf, ~] = tfestimate(leg_noise_hf{i}.Va, leg_noise_hf{i}.da, win, [], [], 1/Ts);
|
||
|
|
int_frf(:, i) = [frf_lf(i_lf); frf_hf(i_hf)];
|
||
|
|
end
|
||
|
|
|
||
|
|
%% Plot the FRF from Va to de (interferometer)
|
||
|
|
figure;
|
||
|
|
tiledlayout(3, 1, 'TileSpacing', 'None', 'Padding', 'None');
|
||
|
|
|
||
|
|
ax1 = nexttile([2,1]);
|
||
|
|
hold on;
|
||
|
|
for i = 1:length(leg_nums)
|
||
|
|
plot(f, abs(int_frf(:, i)), ...
|
||
|
|
'DisplayName', sprintf('Leg %i', leg_nums(i)));
|
||
|
|
end
|
||
|
|
hold off;
|
||
|
|
set(gca, 'XScale', 'log'); set(gca, 'YScale', 'log');
|
||
|
|
ylabel('Amplitude $d_a/V_a$ [m/V]'); set(gca, 'XTickLabel',[]);
|
||
|
|
hold off;
|
||
|
|
legend('location', 'northeast', 'FontSize', 8, 'NumColumns', 2);
|
||
|
|
ylim([1e-9, 1e-3]);
|
||
|
|
|
||
|
|
ax2 = nexttile;
|
||
|
|
hold on;
|
||
|
|
for i = 1:length(leg_nums)
|
||
|
|
plot(f, 180/pi*angle(int_frf(:, i)));
|
||
|
|
end
|
||
|
|
hold off;
|
||
|
|
set(gca, 'XScale', 'log'); set(gca, 'YScale', 'lin');
|
||
|
|
xlabel('Frequency [Hz]'); ylabel('Phase [deg]');
|
||
|
|
hold off;
|
||
|
|
yticks(-360:90:360); ylim([-180 180]);
|
||
|
|
|
||
|
|
linkaxes([ax1,ax2],'x');
|
||
|
|
xlim([10, 2e3]);
|
||
|
|
|
||
|
|
%% Coherence
|
||
|
|
coh_iff = zeros(length(f), length(leg_nums));
|
||
|
|
for i = 1:length(leg_nums)
|
||
|
|
[coh_lf, ~] = mscohere(leg_noise{i}.Va, leg_noise{i}.Vs, win, [], [], 1/Ts);
|
||
|
|
[coh_hf, ~] = mscohere(leg_noise_hf{i}.Va, leg_noise_hf{i}.Vs, win, [], [], 1/Ts);
|
||
|
|
coh_iff(:, i) = [coh_lf(i_lf); coh_hf(i_hf)];
|
||
|
|
end
|
||
|
|
|
||
|
|
%% Plot the coherence
|
||
|
|
figure;
|
||
|
|
hold on;
|
||
|
|
for i = 1:length(leg_nums)
|
||
|
|
plot(f, coh_iff(:, i));
|
||
|
|
end;
|
||
|
|
hold off;
|
||
|
|
xlabel('Frequency [Hz]'); ylabel('Coherence [-]');
|
||
|
|
set(gca, 'XScale', 'log'); set(gca, 'YScale', 'lin');
|
||
|
|
xlim([10, 2e3]); ylim([0, 1]);
|
||
|
|
|
||
|
|
%% FRF estimation of the transfer function from Va to Vs
|
||
|
|
iff_frf = zeros(length(f), length(leg_nums));
|
||
|
|
for i = 1:length(leg_nums)
|
||
|
|
[frf_lf, ~] = tfestimate(leg_noise{i}.Va, leg_noise{i}.Vs, win, [], [], 1/Ts);
|
||
|
|
[frf_hf, ~] = tfestimate(leg_noise_hf{i}.Va, leg_noise_hf{i}.Vs, win, [], [], 1/Ts);
|
||
|
|
iff_frf(:, i) = [frf_lf(i_lf); frf_hf(i_hf)];
|
||
|
|
end
|
||
|
|
|
||
|
|
%% Plot the FRF from Va to Vs
|
||
|
|
figure;
|
||
|
|
tiledlayout(3, 1, 'TileSpacing', 'None', 'Padding', 'None');
|
||
|
|
|
||
|
|
ax1 = nexttile([2,1]);
|
||
|
|
hold on;
|
||
|
|
for i = 1:length(leg_nums)
|
||
|
|
plot(f, abs(iff_frf(:, i)), ...
|
||
|
|
'DisplayName', sprintf('Leg %i', leg_nums(i)));
|
||
|
|
end
|
||
|
|
hold off;
|
||
|
|
set(gca, 'XScale', 'log'); set(gca, 'YScale', 'log');
|
||
|
|
ylabel('Amplitude $V_s/V_a$ [V/V]'); set(gca, 'XTickLabel',[]);
|
||
|
|
hold off;
|
||
|
|
ylim([1e-2, 1e2]);
|
||
|
|
legend('location', 'southeast', 'FontSize', 8, 'NumColumns', 2);
|
||
|
|
|
||
|
|
ax2 = nexttile;
|
||
|
|
hold on;
|
||
|
|
for i = 1:length(leg_nums)
|
||
|
|
plot(f, 180/pi*angle(iff_frf(:, i)));
|
||
|
|
end
|
||
|
|
hold off;
|
||
|
|
set(gca, 'XScale', 'log'); set(gca, 'YScale', 'lin');
|
||
|
|
xlabel('Frequency [Hz]'); ylabel('Phase [deg]');
|
||
|
|
hold off;
|
||
|
|
yticks(-360:90:360); ylim([-180 180]);
|
||
|
|
|
||
|
|
linkaxes([ax1,ax2],'x');
|
||
|
|
xlim([10, 2e3]);
|
||
|
|
|
||
|
|
%% Save the estimated FRF for further analysis
|
||
|
|
save('mat/meas_struts_frf.mat', 'f', 'Ts', 'enc_frf', 'int_frf', 'iff_frf', 'leg_nums');
|