www.pudn.com > slidingmode3.rar > chap4_4plant.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; 
case 1, 
    sys=mdlDerivatives(t,x,u); 
%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  = 3; 
sizes.NumDiscStates  = 0; 
sizes.NumOutputs     = 2; 
sizes.NumInputs      = 1; 
sizes.DirFeedthrough = 0; 
sizes.NumSampleTimes = 0; 
 
sys=simsizes(sizes); 
x0=[0.5,0.5,0]; 
str=[]; 
ts=[]; 
 
function sys=mdlDerivatives(t,x,u) 
 
%Friction 
	Fc=0.28*1000; 
	Fs=0.34*1000; 
	vs=0.01; 
   af=0.02; 
   rou0=260; 
   rou1=2.5; 
	g=Fc+(Fs-Fc)*exp(-(x(2)/vs)^2)+af*x(2); 
	sys(3)=x(2)-(rou0*abs(x(2))/g)*x(3);   %????? 
	dt=rou0*x(3)+rou1*sys(3)+af*x(2); 
 
sys(1)=x(2); 
sys(2)=-25*x(2)+133*u-dt;  
function sys=mdlOutputs(t,x,u) 
 
%Friction 
	Fc=0.28*1000; 
	Fs=0.34*1000; 
	vs=0.01; 
   af=0.02; 
   rou0=260; 
   rou1=2.5; 
	g=Fc+(Fs-Fc)*exp(-(x(2)/vs)^2)+af*x(2); 
	Q=x(2)-(rou0*abs(x(2))/g)*x(3);   %????? 
	dt=rou0*x(3)+rou1*Q+af*x(2); 
 
sys(1)=x(1); 
sys(2)=dt;