% Matlab Init :noexport:ignore: current_dir='/home/thomas/MEGA/These/meas/slip-ring-test/'; %% Clear Workspace and Close figures clear; close all; clc; %% Intialize Laplace variable s = zpk('s'); % Load data % We load the data of the z axis of two geophones. sr_off = load('mat/data_012.mat', 'data'); sr_off = sr_off.data; sr_on = load('mat/data_013.mat', 'data'); sr_on = sr_on.data; % Time Domain % We compare the signal when the Slip-Ring is OFF (figure [[fig:sr_geophone_time_off]]) and when it is ON (figure [[fig:sr_geophone_time_on]]). figure; hold on; plot(sr_off(:, 3), sr_off(:, 1), 'DisplayName', 'Direct'); plot(sr_off(:, 3), sr_off(:, 2), 'DisplayName', 'Slip-Ring'); hold off; legend('Location', 'northeast'); xlabel('Time [s]'); ylabel('Voltage [V]'); % #+NAME: fig:sr_geophone_time_off % #+CAPTION: Comparison of the time domain signals when the slip-ring is OFF % #+RESULTS: fig:sr_geophone_time_off % [[file:figs/sr_geophone_time_off.png]] figure; hold on; plot(sr_on(:, 3), sr_on(:, 1), 'DisplayName', 'Direct'); plot(sr_on(:, 3), sr_on(:, 2), 'DisplayName', 'Slip-Ring'); hold off; legend('Location', 'northeast'); xlabel('Time [s]'); ylabel('Voltage [V]'); % Frequency Domain % We first compute some parameters that will be used for the PSD computation. dt = sr_off(2, 3)-sr_off(1, 3); Fs = 1/dt; % [Hz] win = hanning(ceil(10*Fs)); % Then we compute the Power Spectral Density using =pwelch= function. % Direct measure [pxdoff, ~] = pwelch(sr_off(:, 1), win, [], [], Fs); [pxdon, ~] = pwelch(sr_on(:, 1), win, [], [], Fs); % Slip-Ring measure [pxsroff, f] = pwelch(sr_off(:, 2), win, [], [], Fs); [pxsron, ~] = pwelch(sr_on(:, 2), win, [], [], Fs); % Finally, we compare the Amplitude Spectral Density of the signals (figure [[fig:sr_geophone_asd]]); figure; hold on; plot(f, sqrt(pxdoff), 'DisplayName', 'Direct - OFF'); plot(f, sqrt(pxsroff), 'DisplayName', 'Slip-Ring - OFF'); plot(f, sqrt(pxdon), 'DisplayName', 'Direct - ON'); plot(f, sqrt(pxsron), 'DisplayName', 'Slip-Ring - ON'); 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', 'northeast'); xlim([0.1, 500]); % #+NAME: fig:sr_geophone_asd % #+CAPTION: Comparison of the Amplitude Spectral Sensity % #+RESULTS: fig:sr_geophone_asd % [[file:figs/sr_geophone_asd.png]] xlim([100, 500]); % Load data % We load the data of the z axis of two geophones. sr_lpf_off = load('mat/data_016.mat', 'data'); sr_lpf_off = sr_lpf_off.data; sr_lpf_on = load('mat/data_017.mat', 'data'); sr_lpf_on = sr_lpf_on.data; % Time Domain % We compare the signal when the Slip-Ring is OFF (figure [[fig:sr_lpf_geophone_time_off]]) and when it is ON (figure [[fig:sr_lpf_geophone_time_on]]). figure; hold on; plot(sr_lpf_off(:, 3), sr_lpf_off(:, 1), 'DisplayName', 'Direct'); plot(sr_lpf_off(:, 3), sr_lpf_off(:, 2), 'DisplayName', 'Slip-Ring'); hold off; legend('Location', 'northeast'); xlabel('Time [s]'); ylabel('Voltage [V]'); % #+NAME: fig:sr_lpf_geophone_time_off % #+CAPTION: Comparison of the time domain signals when the slip-ring is OFF % #+RESULTS: fig:sr_lpf_geophone_time_off % [[file:figs/sr_lpf_geophone_time_off.png]] figure; hold on; plot(sr_lpf_on(:, 3), sr_lpf_on(:, 1), 'DisplayName', 'Direct'); plot(sr_lpf_on(:, 3), sr_lpf_on(:, 2), 'DisplayName', 'Slip-Ring'); hold off; legend('Location', 'northeast'); xlabel('Time [s]'); ylabel('Voltage [V]'); % Frequency Domain % We first compute some parameters that will be used for the PSD computation. dt = sr_lpf_off(2, 3)-sr_lpf_off(1, 3); Fs = 1/dt; % [Hz] win = hanning(ceil(10*Fs)); % Then we compute the Power Spectral Density using =pwelch= function. % Direct measure [pxd_lpf_off, ~] = pwelch(sr_lpf_off(:, 1), win, [], [], Fs); [pxd_lpf_on, ~] = pwelch(sr_lpf_on(:, 1), win, [], [], Fs); % Slip-Ring measure [pxsr_lpf_off, f] = pwelch(sr_lpf_off(:, 2), win, [], [], Fs); [pxsr_lpf_on, ~] = pwelch(sr_lpf_on(:, 2), win, [], [], Fs); % Finally, we compare the Amplitude Spectral Density of the signals (figure [[fig:sr_lpf_geophone_asd]]); figure; hold on; plot(f, sqrt(pxd_lpf_off), 'DisplayName', 'Direct - OFF'); plot(f, sqrt(pxsr_lpf_off), 'DisplayName', 'Slip-Ring - OFF'); plot(f, sqrt(pxd_lpf_on), 'DisplayName', 'Direct - ON'); plot(f, sqrt(pxsr_lpf_on), 'DisplayName', 'Slip-Ring - ON'); 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', 'northeast'); xlim([0.1, 500]); % #+NAME: fig:sr_lpf_geophone_asd % #+CAPTION: Comparison of the Amplitude Spectral Sensity % #+RESULTS: fig:sr_lpf_geophone_asd % [[file:figs/sr_lpf_geophone_asd.png]] xlim([100, 500]); % Comparison of with and without LPF figure; hold on; plot(f, sqrt(pxdon), 'DisplayName', 'Direct - ON'); plot(f, sqrt(pxsron), 'DisplayName', 'Slip-Ring - ON'); plot(f, sqrt(pxd_lpf_on), 'DisplayName', 'Direct - ON - LPF'); plot(f, sqrt(pxsr_lpf_on), 'DisplayName', 'Slip-Ring - ON - LPF'); 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', 'northeast'); xlim([0.1, 500]);