How to increase the "linewidth" of given graphs?

I want to increase the linewidth of the following two graphs? But how? The required mat file is hereby attached and the code is given below:

clear;clc;
s=tf('s');
G=(61.73*s^2+2.112e4)/(s^4+52.42*s^3+967.1*s^2+1.793e4*s);
%%%%%%%%%%%%%%
% Contrioller
%%%%%%%%%%%%%%
load PIDGains.mat
[one1 ind]=sort(one,'descend');
[fitness,ind1]=min(one1);
two1=two(ind1,:);
Kp=two1(1);
Ki=two1(2);
Kd=two1(3);
Gc=Kp+Ki/s+Kd*s;
%%%%%%%%%%%%%%%
% Feedback TF
%%%%%%%%%%%%%%
H=1;
%%%%%%%%%%%%%%
% Closed Loop TF
%%%%%%%%%%%%%%
T=feedback(Gc*G*H,1);
%%%%%%%%%%%%%%%%%%
% Step Response of open loop and closed loops
%%%%%%%%%%%%%%%%%%
subplot(2,1,1)
step(G)
subplot(2,1,2)
step(T)

G=stepinfo(G)

G = struct with fields:
         RiseTime: NaN
    TransientTime: NaN
     SettlingTime: NaN
      SettlingMin: NaN
      SettlingMax: NaN
        Overshoot: NaN
       Undershoot: NaN
             Peak: Inf
         PeakTime: Inf

T=stepinfo(T)

T = struct with fields:
         RiseTime: 7.1553e-05
    TransientTime: 1.2930e-04
     SettlingTime: 1.2930e-04
      SettlingMin: 0.9030
      SettlingMax: 0.9977
        Overshoot: 0
       Undershoot: 0
             Peak: 0.9977
         PeakTime: 2.3684e-04

Answer 1

[Walter Roberson]

clear;clc;
s=tf('s');
G=(61.73*s^2+2.112e4)/(s^4+52.42*s^3+967.1*s^2+1.793e4*s);
%%%%%%%%%%%%%%
% Contrioller
%%%%%%%%%%%%%%
load PIDGains.mat
[one1 ind]=sort(one,'descend');
[fitness,ind1]=min(one1);
two1=two(ind1,:);
Kp=two1(1);
Ki=two1(2);
Kd=two1(3);
Gc=Kp+Ki/s+Kd*s;
%%%%%%%%%%%%%%%
% Feedback TF
%%%%%%%%%%%%%%
H=1;
%%%%%%%%%%%%%%
% Closed Loop TF
%%%%%%%%%%%%%%
T=feedback(Gc*G*H,1);
%%%%%%%%%%%%%%%%%%
% Step Response of open loop and closed loops
%%%%%%%%%%%%%%%%%%
ax1 = subplot(2,1,1);
step(G)
ax2 = subplot(2,1,2);
step(T)
G=stepinfo(G)

G = struct with fields:
         RiseTime: NaN
    TransientTime: NaN
     SettlingTime: NaN
      SettlingMin: NaN
      SettlingMax: NaN
        Overshoot: NaN
       Undershoot: NaN
             Peak: Inf
         PeakTime: Inf

T=stepinfo(T)

T = struct with fields:
         RiseTime: 7.1553e-05
    TransientTime: 1.2930e-04
     SettlingTime: 1.2930e-04
      SettlingMin: 0.9030
      SettlingMax: 0.9977
        Overshoot: 0
       Undershoot: 0
             Peak: 0.9977
         PeakTime: 2.3684e-04

set(ax1.Children(1).Children(1), 'LineWidth', 3, 'Color', 'g')
set(ax2.Children(1).Children(2), 'LineWidth', 3, 'Color', 'r')

That is, when you do step() inside a subplot, then a Group object is created, that has 2 line objects as children. The second of the two line objects is the step response. The fact that nothing showed up in green shows that (at least for this purpose) the first line object is nothing of interest.

(You do not need to set the color; I do it here just to emphasize which object has been affected (or not affected.)

[Sadiq]

Thanks a lot dear Walter Roberson for your kind response. I pasted these two lines in my code at bottom

set(ax1.Children(1).Children(1), 'LineWidth', 3, 'Color', 'g')
set(ax2.Children(1).Children(2), 'LineWidth', 3, 'Color', 'r')

and ran the code but it gives me the following error:

Unable to resolve the name 'ax1.Children'.

Error in CL_ResponseWith_PID (line 39)

set(ax1.Children(1).Children(1), 'LineWidth', 3, 'Color', 'g')

[Sadiq]

Sorry I didn't write like these:

ax1 = subplot(2,1,1);
ax2 = subplot(2,1,2);

That's why it gave me the above error. Now I corrected my code and it works. But in the figure only 2nd graph line width is increased not of 1st one. Why is it so?

[Walter Roberson]

The purpose of the code is to illustrate that the second location Children(1).Children(2) is the item to set and that Children(1).Children(1) will not work. Without this test people might tend to think that they could just set the line width of both lines Children(1).Children(:)

[Sadiq]

Thanks a lot dear Walter Roberson for your kind response. Yes, it works now.