%% Clear Workspace and Close figures clear; close all; clc; %% Intialize Laplace variable s = zpk('s'); %% Path for functions, data and scripts addpath('./mat/'); % Path for data %% Colors for the figures colors = colororder; %% Frequency Vector freqs = logspace(1, 3, 1000); % Simulation % In this section, we suppose that we are in the frame of one fast jack (all transformations are already done), and we wish to create a LUT for one fast jack. % Let's say with make a Bragg angle scan between 10deg and 60deg during 100s. Fs = 10e3; % Sample Frequency [Hz] t = 0:1/Fs:10; % Time vector [s] theta = linspace(10, 40, length(t)); % Bragg Angle [deg] % The IcePAP steps are following the theoretical formula: % \begin{equation} % d_z = \frac{d_{\text{off}}}{2 \cos \theta} % \end{equation} % with $\theta$ the bragg angle and $d_{\text{off}} = 10\,mm$. % The motion to follow is then: perfect_motion = 10e-3./(2*cos(theta*pi/180)); % Perfect motion [m] % And the IcePAP is generated those steps: icepap_steps = perfect_motion; % IcePAP steps measured by Speedgoat [m] %% Steps as a function of the bragg angle figure; plot(theta, icepap_steps); xlabel('Bragg Angle [deg]'); ylabel('IcePAP Steps [m]'); % #+name: fig:bragg_angle_icepap_steps_idealized % #+caption: IcePAP Steps as a function of the Bragg Angle % #+RESULTS: % [[file:figs/bragg_angle_icepap_steps_idealized.png]] % Then, we are measuring the motion of the Fast Jack using the Interferometer. % The motion error is larger than in reality to be angle to see it more easily. motion_error = 100e-6*sin(2*pi*perfect_motion/1e-3); % Error motion [m] measured_motion = perfect_motion + motion_error; % Measured motion of the Fast Jack [m] %% Measured Motion and Idealized Motion figure; hold on; plot(icepap_steps, measured_motion, ... 'DisplayName', 'Measured Motion'); plot(icepap_steps, perfect_motion, 'k--', ... 'DisplayName', 'Ideal Motion'); hold off; xlabel('IcePAP Steps [m]'); ylabel('Measured Motion [m]'); legend('location', 'southeast'); % #+name: fig:measured_and_ideal_motion_fast_jacks % #+caption: Measured motion as a function of the IcePAP Steps % #+RESULTS: % [[file:figs/measured_and_ideal_motion_fast_jacks.png]] % Let's now compute the lookup table. % For each micrometer of the IcePAP step, another step is associated that correspond to a position closer to the wanted position. %% Get range for the LUT % We correct only in the range of tested/measured motion lut_range = round(1e6*min(icepap_steps)):round(1e6*max(icepap_steps)); % IcePAP steps [um] %% Initialize the LUT lut = zeros(size(lut_range)); %% For each um in this range for i = 1:length(lut_range) % Get points indices where the measured motion is closed to the wanted one close_points = measured_motion > 1e-6*lut_range(i) - 500e-9 & measured_motion < 1e-6*lut_range(i) + 500e-9; % Get the corresponding closest IcePAP step lut(i) = round(1e6*mean(icepap_steps(close_points))); % [um] end %% Generated Lookup Table figure; plot(lut_range, lut); xlabel('IcePAP input step [um]'); ylabel('Lookup Table output [um]'); % #+name: fig:generated_lut_icepap % #+caption: Generated Lookup Table % #+RESULTS: % [[file:figs/generated_lut_icepap.png]] % The current LUT implementation is the following: motion_error_lut = zeros(size(lut_range)); for i = 1:length(lut_range) % Get points indices where the icepap step is close to the wanted one close_points = icepap_steps > 1e-6*lut_range(i) - 500e-9 & icepap_steps < 1e-6*lut_range(i) + 500e-9; % Get the corresponding motion error motion_error_lut(i) = lut_range(i) + (lut_range(i) - round(1e6*mean(measured_motion(close_points)))); % [um] end % Let's compare the two Lookup Table in Figure [[fig:lut_comparison_two_methods]]. %% Comparison of the two Generated Lookup Table figure; hold on; plot(lut_range, lut, ... 'DisplayName', 'New LUT'); plot(lut_range, motion_error_lut, ... 'DisplayName', 'Old LUT'); hold off; xlabel('IcePAP input step [um]'); ylabel('Lookup Table output [um]'); legend('location', 'southeast'); % #+name: fig:lut_comparison_two_methods % #+caption: Comparison of the two lookup tables % #+RESULTS: % [[file:figs/lut_comparison_two_methods.png]] % If we plot the "corrected steps" for all steps for both methods, we clearly see the difference (Figure [[fig:lut_correct_and_motion_error]]). %% Corrected motion and motion error at each step position figure; hold on; plot(lut_range, lut-lut_range, ... 'DisplayName', 'New LUT'); plot(lut_range, motion_error_lut-lut_range, ... 'DisplayName', 'Old LUT'); hold off; xlabel('IcePAP Steps [um]'); ylabel('Corrected motion [um]'); ylim([-110, 110]) legend('location', 'southeast'); % #+name: fig:lut_correct_and_motion_error % #+caption: LUT correction and motion error as a function of the IcePAP steps % #+RESULTS: % [[file:figs/lut_correct_and_motion_error.png]] % Let's now implement both LUT to see which implementation is correct. icepap_steps_output_new = lut(round(1e6*icepap_steps)-lut_range(1)+1); i = round(1e6*icepap_steps)-motion_error_lut(1)+1; i(i>length(motion_error_lut)) = length(motion_error_lut); icepap_steps_output_old = motion_error_lut(i); motion_new = zeros(size(icepap_steps_output_new)); motion_old = zeros(size(icepap_steps_output_old)); for i = 1:length(icepap_steps_output_new) [~, i_step] = min(abs(icepap_steps_output_new(i) - 1e6*icepap_steps)); motion_new(i) = measured_motion(i_step); [~, i_step] = min(abs(icepap_steps_output_old(i) - 1e6*icepap_steps)); motion_old(i) = measured_motion(i_step); end % The output motion with both LUT are shown in Figure [[fig:compare_old_new_lut_motion]]. % It is confirmed that the new LUT is the correct one. % Also, it is interesting to note that the old LUT gives an output motion that is above the ideal one, as was seen during the experiments. %% Measured Motion and Idealized Motion % Use only middle motion where the LUT is working i = round(0.1*length(icepap_steps)):round(0.9*length(icepap_steps)); figure; hold on; plot(icepap_steps(i), motion_new(i), ... 'DisplayName', 'Motion (new LUT)'); plot(icepap_steps(i), motion_old(i), ... 'DisplayName', 'Motion (old LUT)'); plot(icepap_steps(i), perfect_motion(i), 'k--', ... 'DisplayName', 'Ideal Motion'); hold off; xlabel('IcePAP Steps [m]'); ylabel('Measured Motion [m]'); legend('location', 'southeast');