www.pudn.com > slidingmode5.rar > chap6_4s2.m

%S-function for continuous state equation 
function [sys,x0,str,ts]=s_function(t,x,u,flag) 
 
switch flag, 
%Initialization 
  case 0, 
    [sys,x0,str,ts]=mdlInitializeSizes; 
%Outputs 
  case 3, 
    sys=mdlOutputs(t,x,u); 
%Unhandled flags 
  case {2, 4, 9 } 
    sys = []; 
%Unexpected flags 
  otherwise 
    error(['Unhandled flag = ',num2str(flag)]); 
end 
 
%mdlInitializeSizes 
function [sys,x0,str,ts]=mdlInitializeSizes 
sizes = simsizes; 
sizes.NumContStates  = 0; 
sizes.NumDiscStates  = 0; 
sizes.NumOutputs     = 2; 
sizes.NumInputs      = 4; 
sizes.DirFeedthrough = 1; 
sizes.NumSampleTimes = 0; 
 
sys=simsizes(sizes); 
x0=[]; 
str=[]; 
ts=[]; 
 
function sys=mdlOutputs(t,x,u) 
persistent s0 
 
Bn=25/133; 
Jn=1/133; 
lamt=Bn/Jn; 
 
Jm=1/163;JM=1/103; 
Bm=15/163;BM=35/103; 
 
dM=1.0; 
K=20;  
 
e=u(1);   
de=u(2);  
nu=u(3); 
v=u(4); 
 
s1=de+lamt*e; 
 
if t==0 
   e0=e;de0=de; 
	s0=de0+lamt*e0; 
end 
 
temp0=(1/Jn)*nu-lamt*v; 
   
Ja=1/2*(JM+Jm); 
Ba=1/2*(BM+Bm); 
   
xite=10; 
ft=s0*exp(-xite*t); 
s=s1-ft; 
 
H=dM+1/2*(JM-Jm)*abs(temp0)+1/2*(BM-Bm)*abs(v)+JM*xite*abs(s0)*exp(-xite*t); 
 
ut=-K*s-H*sign(s)+Ja*((1/Jn)*nu-lamt*v)+Ba*v; 
 
sys(1)=ut; 
sys(2)=s;