Continuous state-space system

Library

Linear

Description

This block realizes a continuous-time linear state-space system.

$$\dot x =Ax+Bu$$ (4.1)

$$y =C*x+D*u$$ (4.2)

The system is defined by the $(A,B,C,D)$ matrices and the initial state $x_0$. The dimensions must be compatible.

Dialog Box

Set continuous linear system parameters
A matrix	-1
B matrix	1
C matrix	1
D matrix	0
Initial state	0

• $A$ matrix: square matrix. The $A$ matrix
• B matrix: the $B$ matrix, [] if system has no input
• C matrix: the $C$ matrix , [] if system has no output
• D matrix: the $D$ matrix, [] if system has no D term.
• Initial state: A vector/scalar initial state of the system.

Default properties

• always active: yes
• direct-feedthrough: no
• zero-crossing: no
• mode: no
• number/sizes of inputs: 1 / 1
• number/sizes of outputs: 1 / 1
• number/sizes of activation inputs: 0 /
• number/sizes of activation outputs: 0 /
• continuous-time state: yes
• discrete-time state: no
• name of computational function: csslti

Interfacing function

scilab/macros/scicos_blocks/linear/CLSS_f.sci

Computational function (type 1)

      subroutine csslti(flag,nevprt,t,xd,x,nx,z,nz,tvec,ntvec,
     &     rpar,nrpar,ipar,nipar,u,nu,y,ny)
c     Copyright INRIA
c     Scicos block simulator
c     continuous state space linear system simulator
c     rpar(1:nx*nx)=A
c     rpar(nx*nx+1:nx*nx+nx*nu)=B
c     rpar(nx*nx+nx*nu+1:nx*nx+nx*nu+nx*ny)=C
c     rpar(nx*nx+nx*nu+nx*ny+1:nx*nx+nx*nu+nx*ny+ny*nu)=D
c
      double precision t,xd(*),x(*),z(*),tvec(*),rpar(*),u(*),y(*)
      integer flag,nevprt,nx,nz,ntvec,nrpar,ipar(*)
      integer nipar,nu,ny

c
      la=1
      lb=nx*nx+la
      lc=lb+nx*nu

      if(flag.eq.1.or.flag.eq.6) then
c     y=c*x+d*u     
         ld=lc+nx*ny
         call dmmul(rpar(lc),ny,x,nx,y,ny,ny,nx,1)
         call dmmul1(rpar(ld),ny,u,nu,y,ny,ny,nu,1)
c         if(t.gt.64.0) write(6,'(e15.8,10(e10.3,x))') t,x(1),x(2),
c     $        u(1),y(1) 
      elseif(flag.eq.0) then
c     xd=a*x+b*u
         call dmmul(rpar(la),nx,x,nx,xd,nx,nx,nx,1)
         call dmmul1(rpar(lb),nx,u,nu,xd,nx,nx,nu,1)
c         if(t.gt.64.0) write(6,'(e15.8,10(e10.3,x))') t,x(1),x(2),
c     $        xd(1),xd(2),u(1)
      endif
      return
      end