MATLAB - Contrl theroy - LQG that corresponds to a cheap control strategy

Question

I have been asked to design a CT LQG optimal feedback that corresponds to a cheap control strategy with the given A B and C matrices and analyse the resulting close-loop system (margins).

I have tried different implementations, but so far the response to the impulse stay the same as the original system, so I guess I'm missing something.

Here one of the scripts I coded so far:

A = [-(500/290) -(2350/290) (500/290) (2350/290);
        1           0            0       0  ;
        (500/40) (2350/40) -(500/40) -((2350+19000)/40) ;
        0           0           1           0];

B_u = [ 1/290;0; -1/40;0];
C = [1  0   -1  0;  0   1   0   -1];
D = [0;0];

CTsys = ss(A,B_u,C,D);


%weigth matrices
Q = [10000 0 0 0;
     0 10000 0 0;
     0 0 10000 0;
     0 0 0 10000;];
R = 1; 

%optimal gain 
K = lqr(A,B_u,Q,R)

[kest,L,P] = kalman(CTsys,100,R);
regulator = lqgreg(kest, K);

feedin = [1];
feedout = [1];

cl_sys = feedback(CTsys, regulator, feedin, feedout, +1);

impulse(CTsys,'r--',cl_sys,'b-')

Answer 1

等待大神答复