SB10RD

H-infinity (sub)optimal controller matrices using state feedback and output injection matrices (continuous-time)

[Specification] [Arguments] [Method] [References] [Comments] [Example]

Purpose

  To compute the matrices of an H-infinity (sub)optimal controller

           | AK | BK |
       K = |----|----|,
           | CK | DK |

  from the state feedback matrix F and output injection matrix H as
  determined by the SLICOT Library routine SB10QD.

Specification
      SUBROUTINE SB10RD( N, M, NP, NCON, NMEAS, GAMMA, A, LDA, B, LDB,
     $                   C, LDC, D, LDD, F, LDF, H, LDH, TU, LDTU, TY,
     $                   LDTY, X, LDX, Y, LDY, AK, LDAK, BK, LDBK, CK,
     $                   LDCK, DK, LDDK, IWORK, DWORK, LDWORK, INFO )
C     .. Scalar Arguments ..
      INTEGER            INFO, LDA, LDAK, LDB, LDBK, LDC, LDCK, LDD,
     $                   LDDK, LDF, LDH, LDTU, LDTY, LDWORK, LDX, LDY,
     $                   M, N, NCON, NMEAS, NP
      DOUBLE PRECISION   GAMMA
C     .. Array Arguments ..
      INTEGER            IWORK( * )
      DOUBLE PRECISION   A( LDA, * ), AK( LDAK, * ), B( LDB, * ),
     $                   BK( LDBK, * ), C( LDC, * ), CK( LDCK, * ),
     $                   D( LDD, * ), DK( LDDK, * ), DWORK( * ),
     $                   F( LDF, * ), H( LDH, * ), TU( LDTU, * ),
     $                   TY( LDTY, * ), X( LDX, * ), Y( LDY, * )

Arguments

Input/Output Parameters

  N       (input) INTEGER
          The order of the system.  N >= 0.

  M       (input) INTEGER
          The column size of the matrix B.  M >= 0.

  NP      (input) INTEGER
          The row size of the matrix C.  NP >= 0.

  NCON    (input) INTEGER
          The number of control inputs (M2).  M >= NCON >= 0.
          NP-NMEAS >= NCON.

  NMEAS   (input) INTEGER
          The number of measurements (NP2).  NP >= NMEAS >= 0.
          M-NCON >= NMEAS.

  GAMMA   (input) DOUBLE PRECISION
          The value of gamma. It is assumed that gamma is
          sufficiently large so that the controller is admissible.
          GAMMA >= 0.

  A       (input) DOUBLE PRECISION array, dimension (LDA,N)
          The leading N-by-N part of this array must contain the
          system state matrix A.

  LDA     INTEGER
          The leading dimension of the array A.  LDA >= max(1,N).

  B       (input) DOUBLE PRECISION array, dimension (LDB,M)
          The leading N-by-M part of this array must contain the
          system input matrix B.

  LDB     INTEGER
          The leading dimension of the array B.  LDB >= max(1,N).

  C       (input) DOUBLE PRECISION array, dimension (LDC,N)
          The leading NP-by-N part of this array must contain the
          system output matrix C.

  LDC     INTEGER
          The leading dimension of the array C.  LDC >= max(1,NP).

  D       (input) DOUBLE PRECISION array, dimension (LDD,M)
          The leading NP-by-M part of this array must contain the
          system input/output matrix D.

  LDD     INTEGER
          The leading dimension of the array D.  LDD >= max(1,NP).

  F       (input) DOUBLE PRECISION array, dimension (LDF,N)
          The leading M-by-N part of this array must contain the
          state feedback matrix F.

  LDF     INTEGER
          The leading dimension of the array F.  LDF >= max(1,M).

  H       (input) DOUBLE PRECISION array, dimension (LDH,NP)
          The leading N-by-NP part of this array must contain the
          output injection matrix H.

  LDH     INTEGER
          The leading dimension of the array H.  LDH >= max(1,N).

  TU      (input) DOUBLE PRECISION array, dimension (LDTU,M2)
          The leading M2-by-M2 part of this array must contain the
          control transformation matrix TU, as obtained by the
          SLICOT Library routine SB10PD.

  LDTU    INTEGER
          The leading dimension of the array TU.  LDTU >= max(1,M2).

  TY      (input) DOUBLE PRECISION array, dimension (LDTY,NP2)
          The leading NP2-by-NP2 part of this array must contain the
          measurement transformation matrix TY, as obtained by the
          SLICOT Library routine SB10PD.

  LDTY    INTEGER
          The leading dimension of the array TY.
          LDTY >= max(1,NP2).

  X       (input) DOUBLE PRECISION array, dimension (LDX,N)
          The leading N-by-N part of this array must contain the
          matrix X, solution of the X-Riccati equation, as obtained
          by the SLICOT Library routine SB10QD.

  LDX     INTEGER
          The leading dimension of the array X.  LDX >= max(1,N).

  Y       (input) DOUBLE PRECISION array, dimension (LDY,N)
          The leading N-by-N part of this array must contain the
          matrix Y, solution of the Y-Riccati equation, as obtained
          by the SLICOT Library routine SB10QD.

  LDY     INTEGER
          The leading dimension of the array Y.  LDY >= max(1,N).

  AK      (output) DOUBLE PRECISION array, dimension (LDAK,N)
          The leading N-by-N part of this array contains the
          controller state matrix AK.

  LDAK    INTEGER
          The leading dimension of the array AK.  LDAK >= max(1,N).

  BK      (output) DOUBLE PRECISION array, dimension (LDBK,NMEAS)
          The leading N-by-NMEAS part of this array contains the
          controller input matrix BK.

  LDBK    INTEGER
          The leading dimension of the array BK.  LDBK >= max(1,N).

  CK      (output) DOUBLE PRECISION array, dimension (LDCK,N)
          The leading NCON-by-N part of this array contains the
          controller output matrix CK.

  LDCK    INTEGER
          The leading dimension of the array CK.
          LDCK >= max(1,NCON).

  DK      (output) DOUBLE PRECISION array, dimension (LDDK,NMEAS)
          The leading NCON-by-NMEAS part of this array contains the
          controller input/output matrix DK.

  LDDK    INTEGER
          The leading dimension of the array DK.
          LDDK >= max(1,NCON).

Workspace
  IWORK   INTEGER array, dimension (LIWORK), where
          LIWORK = max(2*(max(NP,M)-M2-NP2,M2,N),NP2)

  DWORK   DOUBLE PRECISION array, dimension (LDWORK)
          On exit, if INFO = 0, DWORK(1) contains the optimal
          LDWORK.

  LDWORK  INTEGER
          The dimension of the array DWORK.
          LDWORK >= max(1, M2*NP2 + NP2*NP2 + M2*M2 +
                        max(D1*D1 + max(2*D1, (D1+D2)*NP2),
                            D2*D2 + max(2*D2, D2*M2), 3*N,
                            N*(2*NP2 + M2) +
                            max(2*N*M2, M2*NP2 +
                                        max(M2*M2+3*M2, NP2*(2*NP2+
                                               M2+max(NP2,N))))))
          where D1 = NP1 - M2, D2 = M1 - NP2,
               NP1 = NP - NP2, M1 = M - M2.
          For good performance, LDWORK must generally be larger.
          Denoting Q = max(M1,M2,NP1,NP2), an upper bound is
          max( 1, Q*(3*Q + 3*N + max(2*N, 4*Q + max(Q, N)))).

Error Indicator
  INFO    INTEGER
          = 0:  successful exit;
          < 0:  if INFO = -i, the i-th argument had an illegal
                value;
          = 1:  if the controller is not admissible (too small value
                of gamma);
          = 2:  if the determinant of Im2 + Tu*D11HAT*Ty*D22 is zero.

Method
  The routine implements the Glover's and Doyle's formulas [1],[2].

References
  [1] Glover, K. and Doyle, J.C.
      State-space formulae for all stabilizing controllers that
      satisfy an Hinf norm bound and relations to risk sensitivity.
      Systems and Control Letters, vol. 11, pp. 167-172, 1988.

  [2] Balas, G.J., Doyle, J.C., Glover, K., Packard, A., and
      Smith, R.
      mu-Analysis and Synthesis Toolbox.
      The MathWorks Inc., Natick, Mass., 1995.

Numerical Aspects
  The accuracy of the result depends on the condition numbers of the
  input and output transformations.

Further Comments
  None
Example

Program Text

  None
Program Data
  None
Program Results
  None

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