Verify transfer function into SS

I am facing a problem of how to definw this transfer function then transfer it to state space

how to write the tf in this case then which method should I use to find state space?!

[Star Strider]

Reference: How to write polynomial matrix and use tf to ss

[Abdullah Alabdrabalnabi]

I have faced wierd problem in matrix runing this command

A=[0 0 1 0;0 0 0 1;-112.11 70.07 -2.79 1.54;280.28 -224.22 7.75 -4.64];
B=[0 0;0 0;19.04 -47.61;-47.61 152.38];
C=[1 0 0 0;0 1 0 0];
D=[0 0;0 0];
x=ss(A,B,C,D);
[num,den]=ss2tf(A,B,C,D,2);

the valuess of num and den are not desired but when I impelement the same code in Octave I got what I am looking for

what is the matter !?

[Walter Roberson]

The system appears to have been normalized to a leading denominator coefficient of 1.

[Abdullah Alabdrabalnabi]

can I undo this? if yes how ?

[Walter Roberson]

No, the internal representations automatically normalize the leading coefficient.

Answer 1

[Maadhav Akula]

You can define the transfer function as follows:

den = [10 7.4 337.3 171.1 5498.1];
sys1 = tf([0 0 19.04 15.03 933.1],den);
sys2 = tf([0 0 -47.6 14.73 -1.03],den);
sys3 = tf([0 0 -47.6 13.8 2.2],den);
sys4 = tf([0 0 152.4 56.2 3739.2],den);
sys = [sys1 sys2; sys3 sys4];

Now to get the state space co-efficients use the ss function :

State_space_coefficients = ss(sys)