Need assistance hard coding

clear, clc
m1 = 1;
m2 = 4;
mu1 = 0.2;
mu2 = 5;
b = 0.2;
t = 0:0.1:50;
for k = 0:0.2:1
    A = [0 1 0 0; (-k) -0.4 k 0.4; 0 0 0 1; (k/4) 0.1 (-k/4) -1.3];
    B = [5; 0; 0; 0];
    C = eye(4);
    D = 0;
    u = zeros(size(t));
    u(1,1) = 5;
    sys = ss(A,B,C,D);
    [y,x] = lsim(sys, u, t);
    subplot(2,2,1)
    plot(t,y(:,1))
    title('Displacement - B=0.2 Variying K')
    xlabel('Time (s)')
    ylabel('Displacement')
    hold on
    plot(t,y(:,3))
    subplot(2,2,2)
    plot(t,y(:,2))
    title('Velocity - B=0.2 Variying K')
    xlabel('Time')
    ylabel('Velocity')
    hold on
    plot(t,y(:,4))
end
for b1 = 0:0.2:1
    A = [0 1 0 0; (-0.2) -(b1+0.2) 0.2 (0.2+b1); 0 0 0 1; -0.05 (0.2+b1)/4 -0.05 -(b1+5)/4];
    B = [5; 0; 0; 0];
    C = eye(4);
    D = 0;
    u = zeros(size(t));
    u(1,1) = 5;
    sys = ss(A,B,C,D);
    [y,x] = lsim(sys, u, t);
    subplot(2,2,3)
    plot(t,y(:,1))
    title('Displacement - K=0.2 Variying B')
    xlabel('Time (s)')
    ylabel('Displacement')
    hold on
    plot(t,y(:,3))
    subplot(2,2,4)
    plot(t,y(:,2))
    title('Velocity - K=0.2 Variying B')
    xlabel('Time (s)')
    ylabel('Velocity')
    hold on
    plot(t,y(:,4))
end

% trying to figureout why my output looks nothing simular to these graphs. My output graphs are drastically different.

[Image Analyst]

Which is the 4 ss functions are you using? Which toolbox?

ss

ss

ss

ss

[DGM]

That'd be from CST.

[Star Strider]

It’s difficult to determine what you’re doing. The lsim function is good for random inputs, however the step or impulse functions (or stepplot or impulseplot) might be better for this. They have options you can set as well to vary the step amplitude. See the documentation for each function and setoptions for details.