num=-[948.12, 30325, 56482, 1215.3];
den=[1, 64.554, 1167, 3728.6, -5495.4, 1102, 708.1];
G=ss(tf(num,den)); Xi=1e-4; Theta=1e-5; 
Q=G.c'*G.c; R=1; [Kc,P]=lqr(G.a,G.b,Q,R); 
q0=[1,1e4,1e6,1e8,1e10,1e12,1e14];  w=logspace(-2,2);
[af,bf,cf,df]=ltru(G.a,G.b,G.c,G.d,Kc,Xi,Theta,q0,w);
Gc=zpk(ss(af,bf,cf,df))

q=10e10; 
[af,bf,cf,df]=ltru(G.a,G.b,G.c,G.d,Kc,Xi,Theta,q,w);
Gc=ss(af,bf,cf,df); G_c=feedback(G*Gc,1);
t=0:0.01:10; step(G_c,t)