% Chapter 4: Figure 4.30
%
% Compute the input step response for Ka=10.  

%
Ka=10; % Change Ka=80 to obtain the other step response.
nf=[5000]; df=[1 1000]; sysf=tf(nf,df);
ng=[1]; dg=[1 20 0]; sysg=tf(ng,dg);
sysa=series(Ka*sysf,sysg);
sys=feedback(sysa,[1]);
t=[0:0.01:2];
y=step(sys,t); plot(t,y)
ylabel('y(t)'), xlabel('Time (s)'), grid