pid tunnig with non unity feedback

Hello, I would like to know what the code would be to obtain the PID values for the sys below,

with G , H are two tranfers functions and C is the pid controller

i used the following code but it didn't work!!!

C=pidtune(feedback(G,H),'pid',1.0)
sys=feedback(C*G,H)
step(sys)

Thank you.

A greeting.

Answer 1

[Birdman]

Try the following approach:

s=tf('s'); %needed to define transfer function in s domain
G=1/3*s+4;H=1/(0.1*s+1); %if feedback is not unity, then it has to be considered in open loop, as G*H
C=pidtune(G*H,'PID',1) 
sys=(C*G)/(1+C*G*H)
step(sys)

[metchat aissa]

thank for your help :)