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010 A singular H∞ control problem
Abstracts Abstracts m tlus secuon are from papers presented at 12th IFAC TRTENN IAL WORLD CONGRESS ON AUTOMATIC CONTROL (VOLUME 2) * Sydney, Austraha, 18-23 July 1993 Full papers appear m the Proceedmgs volume to wtnch the page numbers relate, pubhshed by IFAC and avadable from Elsevier Sctence (ISBN 0 08 042213 6)
001 Synthesis of Robust Controllers with Few De~-ees of Freedom for Systems with Structured Real Parametrk Uncertainty S.J. Saleh, B R. Barmish, I.R. Petersea, pp 1-4
006 From Nyquist to Kharitonov. Synthesis of Robust Controllers C. Adballah, P Dorato, F P&rez, D. Docampo, pp 23.26 This paper p~sents new ways of robusdy stabhTmg a fam_tly of smgle-mput-smgle-ontput (SISO) systems, by combining He. and extreme-point results The mouvatton for the paper as that the stabthzauon of more than 2 plants LSan open problem that greatly lmuts the apphcauon of most recent extreme-point stabthzabthty results
The focus of tins paper is the problem of synthessnng a controller whtch achteves "robust performance" for a gsven fanuly of lmcar systems, obtained as a result of structured ~ uncertainty The vector of uncertain parameters corresponds to plant coefficaents and Is restncted to a sphere The problem of syntheslnng such a controller as eqmvalent to ~ mterpolauon problem mvolvmg a frequency-dependant "fourth-order set" m the complex plane. For the specud case when the controller has a fixed structure, tl-us mteqmlauon problem as transferred to the space of controller parameten For controllen descnbed by two or three perameten, a complete soluuon to the synthesas problem as obtained
007 Power Distribution Approach in Robust Control A. Megretski, pp 27-30 It ts shown how recent robust control methods, mcludmg msynthcsas, quadrauc stahhty, operator passxvtty (posmvlty), noulmear opurmzauon, H-mfimty control, et al , c.m be c o m h n e d within the power chstnbuuon framework, to 3qeld a umfied way of solvmg vanom stabday/pedormance analysas and synthests problems Conservauveness assues are also dascussed
002 Robust Control Synthesis by Convex Optimization Projective Parameterization and Duality A. Megretski, A Rantzar, pp 5-8 Th~ paper treats a robustness olxumzauon problem for Imear ume-mvanant systems wah real parmnemc unceruunty It as shown that arbxtrardy aceurate upper and lower bounds on the optnnal "robustnessmargm" can be obtained by firate-¢hmenslonal c~lvex olXmuzaUon The upper bound as based on a new duahty result for a generahzed mturpolauon problem
008 Robust Nonlinear H~/Adaptive Control of Robot Manipulator Motion Weining Feng, I. Postlethwaite, pp 31-34 In roboucs, uncemunues are always present and sometnnes slgmficent. In tins paper, modelling errors are represented by a class of bounded dasturbances m the mpet control channels (torques) of the robot. A measure of the robot system's abthty to reject these &smrbances xs formulated m a nonlmcar Hoe norm sense and a control desxgn as proposed to achaeve optanal dasturbance rejection If more-detailed mfonnauou as avatlable on the plant/medel masmateh, the control destgn can be mod~e.d to ~ t e an adapttve scheme to reduce conservauveness and nnpmve robust performance. It as shown how the nonlinear quadrauc optmuzauon problem as a specaal case of noulmear He. opmmzauen
003 Robust Pole Placement Using Two-Pole Dominant Models P padmanabhaa, C.V. Hollot, W. Siegl, pp 9-14 Tim paper couslders the problem of rotmst pole placement usm8 fixed-order compensaUon It ts assumed that the ccefficlents of the numerator and dencmmator polynouaals of the uncellmn pla~t depend molulmeady on the "parameters" and that the des~,n specaflcauons are 81yen m the form of a two-pole dominant model A des~n methodology for choosmg a fixed-order compensator as presented, winch ensures that all the roots of the dosed-lnop polynomud he m the reglens pt~.scnbed by the two-pole dominant model
009 Optimal Guaranteed Cost Control of Discrete-Time 004 Model Following Robust Control of Systems with Large Size Uncertain Parameters Huaizhong Li, Mlnyue Fu, pp 15-18
Uncertain Linear Systems I.R. patersen, D.C McFarlane, M.A. Rotea, pp 35-38 Tius paper extends the Rtccau equauon approach to quadraucally stablhTmg an tmceRam chscre.te-ttmelinear system to allow for a quadrauc cost funozon. For the state feedback case, the controller as constructed by solvmg an algebnuc RdCcaUequaUon of the type For the general output feedback case, the problem as converted to a rimmed H 2 / H . . optanal control problem that can be solved vra a convex pmgrmmmng approach
Thas paper desenbes a robust controller destgn techmquc for lmcar and noulmear smgle-mput sm~ie-onqmt mmnnum-phase systems w~th known and constant relauve degree and bounded peramcmc un~rtamuos Under some condmons, ~t as shown that an ompat feedback controller wuh a srmple structure can be desxsned for the glven system, such that the closed-loop system as robustly stable and achieves specdied modcl-followm8 performance
010 A Singular ~ Control Problem T. Mita, J Matson, pp 39-44
005 Robust Control Analysis Considering Real Parametric Perturbations Based on Sign ]Definite Condition T Kimura, S. Hara, pp 19-22
An He. control problem as solved when D12 as of row full rank and/or D2t as of colmrm full rank, and an exphcat paramemzauon of the Hoe controller as denved. Proper use of free parameters of the He. controller enables one to doslsn a control system havmg better control performance than the convenuoml H~ control system where D12 and Dgt are assumed to be of column full rank and row full rank, respecuvely
Convement tests for D-stabthty, Hoe-norm constntmts and gain/phase margin constramts of one-paranmter systems are proposed m thts paper. These tests are conducted on the barn of the sxgn defimte conchuon and the Euchdean algorithm m mamx form, which can be camed out m a fimte number of steps
707
001 Synthesis of Robust Controllers with Few De~-ees of Freedom for Systems with Structured Real Parametrk Uncertainty S.J. Saleh, B R. Barmish, I.R. Petersea, pp 1-4
006 From Nyquist to Kharitonov. Synthesis of Robust Controllers C. Adballah, P Dorato, F P&rez, D. Docampo, pp 23.26 This paper p~sents new ways of robusdy stabhTmg a fam_tly of smgle-mput-smgle-ontput (SISO) systems, by combining He. and extreme-point results The mouvatton for the paper as that the stabthzauon of more than 2 plants LSan open problem that greatly lmuts the apphcauon of most recent extreme-point stabthzabthty results
The focus of tins paper is the problem of synthessnng a controller whtch achteves "robust performance" for a gsven fanuly of lmcar systems, obtained as a result of structured ~ uncertainty The vector of uncertain parameters corresponds to plant coefficaents and Is restncted to a sphere The problem of syntheslnng such a controller as eqmvalent to ~ mterpolauon problem mvolvmg a frequency-dependant "fourth-order set" m the complex plane. For the specud case when the controller has a fixed structure, tl-us mteqmlauon problem as transferred to the space of controller parameten For controllen descnbed by two or three perameten, a complete soluuon to the synthesas problem as obtained
007 Power Distribution Approach in Robust Control A. Megretski, pp 27-30 It ts shown how recent robust control methods, mcludmg msynthcsas, quadrauc stahhty, operator passxvtty (posmvlty), noulmear opurmzauon, H-mfimty control, et al , c.m be c o m h n e d within the power chstnbuuon framework, to 3qeld a umfied way of solvmg vanom stabday/pedormance analysas and synthests problems Conservauveness assues are also dascussed
002 Robust Control Synthesis by Convex Optimization Projective Parameterization and Duality A. Megretski, A Rantzar, pp 5-8 Th~ paper treats a robustness olxumzauon problem for Imear ume-mvanant systems wah real parmnemc unceruunty It as shown that arbxtrardy aceurate upper and lower bounds on the optnnal "robustnessmargm" can be obtained by firate-¢hmenslonal c~lvex olXmuzaUon The upper bound as based on a new duahty result for a generahzed mturpolauon problem
008 Robust Nonlinear H~/Adaptive Control of Robot Manipulator Motion Weining Feng, I. Postlethwaite, pp 31-34 In roboucs, uncemunues are always present and sometnnes slgmficent. In tins paper, modelling errors are represented by a class of bounded dasturbances m the mpet control channels (torques) of the robot. A measure of the robot system's abthty to reject these &smrbances xs formulated m a nonlmcar Hoe norm sense and a control desxgn as proposed to achaeve optanal dasturbance rejection If more-detailed mfonnauou as avatlable on the plant/medel masmateh, the control destgn can be mod~e.d to ~ t e an adapttve scheme to reduce conservauveness and nnpmve robust performance. It as shown how the nonlinear quadrauc optmuzauon problem as a specaal case of noulmear He. opmmzauen
003 Robust Pole Placement Using Two-Pole Dominant Models P padmanabhaa, C.V. Hollot, W. Siegl, pp 9-14 Tim paper couslders the problem of rotmst pole placement usm8 fixed-order compensaUon It ts assumed that the ccefficlents of the numerator and dencmmator polynouaals of the uncellmn pla~t depend molulmeady on the "parameters" and that the des~,n specaflcauons are 81yen m the form of a two-pole dominant model A des~n methodology for choosmg a fixed-order compensator as presented, winch ensures that all the roots of the dosed-lnop polynomud he m the reglens pt~.scnbed by the two-pole dominant model
009 Optimal Guaranteed Cost Control of Discrete-Time 004 Model Following Robust Control of Systems with Large Size Uncertain Parameters Huaizhong Li, Mlnyue Fu, pp 15-18
Uncertain Linear Systems I.R. patersen, D.C McFarlane, M.A. Rotea, pp 35-38 Tius paper extends the Rtccau equauon approach to quadraucally stablhTmg an tmceRam chscre.te-ttmelinear system to allow for a quadrauc cost funozon. For the state feedback case, the controller as constructed by solvmg an algebnuc RdCcaUequaUon of the type For the general output feedback case, the problem as converted to a rimmed H 2 / H . . optanal control problem that can be solved vra a convex pmgrmmmng approach
Thas paper desenbes a robust controller destgn techmquc for lmcar and noulmear smgle-mput sm~ie-onqmt mmnnum-phase systems w~th known and constant relauve degree and bounded peramcmc un~rtamuos Under some condmons, ~t as shown that an ompat feedback controller wuh a srmple structure can be desxsned for the glven system, such that the closed-loop system as robustly stable and achieves specdied modcl-followm8 performance
010 A Singular ~ Control Problem T. Mita, J Matson, pp 39-44
005 Robust Control Analysis Considering Real Parametric Perturbations Based on Sign ]Definite Condition T Kimura, S. Hara, pp 19-22
An He. control problem as solved when D12 as of row full rank and/or D2t as of colmrm full rank, and an exphcat paramemzauon of the Hoe controller as denved. Proper use of free parameters of the He. controller enables one to doslsn a control system havmg better control performance than the convenuoml H~ control system where D12 and Dgt are assumed to be of column full rank and row full rank, respecuvely
Convement tests for D-stabthty, Hoe-norm constntmts and gain/phase margin constramts of one-paranmter systems are proposed m thts paper. These tests are conducted on the barn of the sxgn defimte conchuon and the Euchdean algorithm m mamx form, which can be camed out m a fimte number of steps
707