Create and Save multiple animated plots on the same axes

So I created a plot comparing my P, I, PID,PI controllers and the open loop system on the same figure !!

I want to create an animated plot of all these in the same figure and then record a video.

All the simulations run until 1.4 seconds, but the number of points in each time period is different.

Below is code for plotting multiple plots together

figure()
plot(t_plant, squeeze(y_plant), 'LineWidth', 2);
hold on
grid on
plot(t_P, squeeze(y_P), 'LineWidth', 2);
plot(t_I, squeeze(y_I), 'LineWidth', 2);
plot(t_PI, squeeze(y_PI), 'LineWidth', 2);
plot(t_PID, squeeze(y_PID), 'LineWidth', 3);


%  2% settling time refrence line
hRef1=refline(0,1);
set(hRef1,'color','b'); % Max horizontal
hRef2=refline(0,1.02);
set(hRef2,'color','r','linestyle','--'); % Max horizontal
hRef3=refline(0,0.98);
set(hRef3,'color','r','linestyle','--'); % Min horizontal
hold off
title('Step Response');
xlabel('Time (sec)');
ylabel('Step Response');
h = legend('Open-loop Plant', 'P', 'I', 'PI', 'PID', '1 sec', '2% S.T range', '2% S.T range');
set(h, 'Location','southeast');
ylim([0 1.5]);

This was the code I used for plotting multiple animated plots together and saving it to a video:

% Create Animated Plot

y_P_Final = squeeze(y_P);
y_I_Final = squeeze(y_I);
y_PI_Final = squeeze(y_PI);
y_PID_Final = squeeze(y_PID);
y_plant_Final = squeeze(y_plant);

% Make some data
% Initialize video
myVideo = VideoWriter('OverallCompensatorComparison'); % open video file
myVideo.FrameRate = 10;  % can adjust this, 5 - 10 works well for me
open(myVideo)
% Plot in a loop and grab frames
for i=1:1:length(t_plant)
    plot(t_plant(1:i), y_plant_Final(1:i), 'LineWidth', 2);
    plot(t_P(1:i), y_P_Final(1:i), 'LineWidth', 2);
    plot(t_I(1:i), y_I_Final(1:i), 'LineWidth', 2);
    plot(t_PI(1:i), y_PI_Final(1:i), 'LineWidth', 2);
    plot(t_PID(1:i), y_PID_Final(1:i), 'LineWidth', 3);
    ylim([0, 1.5])
    xlim([0, 1.4])
    pause(0.01)  % Pause and grab frame
    frame = getframe(gcf); %get frame
    writeVideo(myVideo, frame);
end

Data points are all included in the attached .mat file.

Answer 1

[Walter Roberson]

find the min() and max() over all of the times, and linspace() up a time vector over that range. Now go through the 5 variables and interp1() them to the common time base. Now you can plot them over the common time base. (I suggest using animatedline() )

[Japnit Sethi]

I was able to normalise the 5 varaibles data set at the same time step via interpolation. Any suggestions on the animation and storing in video format ?

[Japnit Sethi]

Was finally able to create a video of multiple plots in one figure

% Create Animated Plot
t_animation = linspace(0, 1.4);
t_animation = t_animation';
y_plant_Final = squeeze(y_plant);
y_P_Final = squeeze(y_P);
y_I_Final = squeeze(y_I);
y_PI_Final = squeeze(y_PI);
y_PID_Final = squeeze(y_PID);


% Normalising to same time step of 0 to 1.4 sec for each output
y_plant_Final_animation = interp1(t_plant(:,1), y_plant_Final(:,1), t_animation(:,1));
y_P_Final_animation = interp1(t_P(:,1),y_P_Final(:,1), t_animation(:,1));
y_I_Final_animation = interp1(t_I(:,1), y_I_Final(:,1), t_animation(:,1));
y_PI_Final_animation = interp1(t_PI(:,1), y_PI_Final(:,1), t_animation(:,1));
y_PID_Final_animation = interp1(t_PID(:,1), y_PID_Final(:,1), t_animation(:,1));


myVideo = VideoWriter('OverallCompensatorComparison'); % open video file
myVideo.FrameRate = 50;  
open(myVideo)

figure 
h1 = animatedline('Color','b','LineWidth', 2.5); 
h2 = animatedline('Color','r','LineWidth', 2.5);
h3 = animatedline('Color', '#EDB120','LineWidth', 2.5);
h4 = animatedline('Color','#7E2F8E','LineWidth', 2.5);
h5 = animatedline('Color','g','LineWidth', 2.5);
for k = 1:length(t_animation) 
  addpoints(h1, t_animation(k),y_plant_Final_animation(k)); 
  addpoints(h2, t_animation(k),y_P_Final_animation(k)); 
  addpoints(h3, t_animation(k),y_I_Final_animation(k)); 
  addpoints(h4, t_animation(k),y_PI_Final_animation(k)); 
  addpoints(h5, t_animation(k),y_PID_Final_animation(k));
  
  %  2% settling time refrence line
  hRef1=refline(0,1);
  set(hRef1,'color','b'); % Max horizontal
  hRef2=refline(0,1.02);
  set(hRef2,'color','r','linestyle','--'); % Max horizontal
  hRef3=refline(0,0.98);
  set(hRef3,'color','r','linestyle','--'); % Min horizontal
  pause(0.01)  % Pause and grab frame
  frame = getframe(gcf); % get frame
  writeVideo(myVideo, frame);
  title('Step Response');
  xlabel('Time (sec)');
  ylabel('Step Response');
  h = legend('Open-loop Plant', 'P', 'I', 'PI', 'PID', '1 sec', '2% S.T range', '2% S.T range');
  set(h, 'Location','southeast');
  ylim([0 1.5]);
  xlim([0 1.4]);
end
% In order to maximize the figure window in Windows
set(gcf, 'Units', 'Normalized', 'OuterPosition', [0, 0.04, 1, 0.96]);

close(myVideo)
drawnow

[Walter Roberson]

t_animation = linspace(0, 1.4);

That is a row vector

y_plant_Final_animation = interp1(t_plant(:,1), y_plant_Final(:,1), t_animation(:,1));

There, t_animation(:,1) is referring to t_animation as if it were a column vector or a 2D array with the interesting information down the first column. But because it is a row vector, t_animation(:,1) is the scalar which is the initial value, 0 . It seems more likely to me that you would be wanting to use t_animation or t_animation(1,:)