Problem in writing MATLAB code of Simulink model (state space)

Hi, I want to write my simulink model into state space model.

Pictures of my simulink model are attached. What I tried so far (and isn't working) is:

dt=0.01;
t=0:dt:10;
for i=1:length(t)
x=A*x+B*u;
u=(G*ref-K*x);
x = cumtrapz(x);
% fun = @(x) x;
% x = integral(fun,0,Inf);
pause;
end

But its results are way different than that of simulink model. Kindly guide me how should I do it.

[Abdullah Irfan]

Anyone???

Answer 1

[Raj]

"I want to write my simulink model into state space model" - Your simulink model is pretty straightforward and already in standard form:

xdot=Ax+Bu
y=Cx+Du

You have your A,B & C matrices. D is zero in your case. There is no need to use the MATLAB function block to complicate things. Just use the Simulink State Space block. Feed in the matrices and you are done!!

[Abdullah Irfan]

"There is no need to use the MATLAB function block to complicate things. Just use the Simulink State Space block. Feed in the matrices and you are done!!"

I was doing the same. But then I needed to transmit data serially and take data from the other device while this model is working.

I tried to use serial send/receive blocks but they were complicating the things, so my last resort is to convert block parameters into matlab code. I think real problem is integration block, I don't know which command replicates simulink integration block (integral, trapz and cumtrapz aren't those at least)