how can i solve this error in simulink?

hello.

i can't solve this error.

i attached simulink file.

( dynsys block function is system's dynamic in state space, ric_schur solve Riccati equation and fcn block function is input)

Answer 1

[Ameer Hamza]

In the block 'fcn', correct these lines

R=[1 0 0 0;
   0 1 0 0;
   0 0 1 0;
   0 0 0 1];
       %^ this space is missing in your file
u =-inv(R)*B*P*x1;
           %^ do not take transpose of P, it is already column vector

Also in this function

function [ddy,ddq] = dynsys(y,ydot,q,qdot,u)
% 4 states (x): 
%% parameters
Phils=-0.1104;M=1.1637;K=2.9327;alpha=0.183;
Gamma=0.4537;D=0.6;ws=9.896;F=0.42;G=0.028;
clo=0.28;Lambda=0.0676;
%% Obtain x, u and y
% x
y=x(1);
ydot=x(2);
q=x(3);
qdot=x(4);
%% y
ddy=(1/M)*(-(2*alpha)/(D*ws)*Gamma*x(2)-K*x(1)+Gamma*x(3)+Phils*u);
ddq=ws*G*clo^2*x(4)-ws^2*x(3)-Lambda*x(3)^2*x(4)+((ws*F)/(D))*x(2);

Input variable is 'y', but you are using x(1), x(2) in your code. Correct variable names according to your equations.

If you resolve this issue, hopefully all the errors will get resolved.

[zahra zamani]

yes , thank you so much

[Ameer Hamza]

Glad to be of help.