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Combined H (infinity) -feedback control and iterative learning control design with application to nanopositioning systems / Brian E. Helfrich in IEEE Transactions on control systems technology, Vol. 18 N° 2 (Mars 2010) 

Public ISBD [article]  in IEEE Transactions on control systems technology > Vol. 18 N° 2 (Mars 2010) . - pp. 336-351 Titre : Combined H (infinity) -feedback control and iterative learning control design with application to nanopositioning systems Type de document : texte imprimé Auteurs : Brian E. Helfrich, Auteur ; Chibum Lee, Auteur ; Douglas A. Bristow, Auteur Année de publication : 2011 Article en page(s) : pp. 336-351 Note générale : Génie Aérospatial Langues : Anglais (eng) Mots-clés : Iterative  learning  control  (ILC)  Nanopositioning  Precision  motion  control  (PMC) Index. décimale : 629.1 Résumé : This paper examines a coordinated feedback and feedforward control design strategy for precision motion control (PMC) systems. It is assumed that the primary exogenous signals are repeated; including disturbances and references. Therefore, an iterative learning control (ILC) feedforward strategy can be used. The introduction of additional non-repeating exogenous signals, including disturbances, noise, and reset errors, necessitates the proper coordination between feedback and feedforward controllers to achieve high performance. A novel ratio of repeated versus non-repeated signal power in the frequency domain is introduced and defined as the repetitive-to-non-repetitive (RNR) ratio. This frequency specific ratio allows for a new approach to delegating feedback and feedforward control efforts based on RNR value. A systematic procedure for control design is given whereby the feedback addresses the non-repeating exogenous signal content (RNR ≪ 0 dB) and the feedforward ILC addresses the repeating signal content (RNR ≫ 0 dB). To illustrate the design approach, two case studies using different nano-positioning devices are given. DEWEY : 629.1 ISSN : 1063-6536 En ligne : http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=5169845 [article] Combined H (infinity) -feedback control and iterative learning control design with application to nanopositioning systems [texte imprimé] / Brian E. Helfrich, Auteur ; Chibum Lee, Auteur ; Douglas A. Bristow, Auteur . - 2011 . - pp. 336-351. Génie Aérospatial Langues : Anglais (eng) in IEEE Transactions on control systems technology > Vol. 18 N° 2 (Mars 2010) . - pp. 336-351 Mots-clés : Iterative  learning  control  (ILC)  Nanopositioning  Precision  motion  control  (PMC) Index. décimale : 629.1 Résumé : This paper examines a coordinated feedback and feedforward control design strategy for precision motion control (PMC) systems. It is assumed that the primary exogenous signals are repeated; including disturbances and references. Therefore, an iterative learning control (ILC) feedforward strategy can be used. The introduction of additional non-repeating exogenous signals, including disturbances, noise, and reset errors, necessitates the proper coordination between feedback and feedforward controllers to achieve high performance. A novel ratio of repeated versus non-repeated signal power in the frequency domain is introduced and defined as the repetitive-to-non-repetitive (RNR) ratio. This frequency specific ratio allows for a new approach to delegating feedback and feedforward control efforts based on RNR value. A systematic procedure for control design is given whereby the feedback addresses the non-repeating exogenous signal content (RNR ≪ 0 dB) and the feedforward ILC addresses the repeating signal content (RNR ≫ 0 dB). To illustrate the design approach, two case studies using different nano-positioning devices are given. DEWEY : 629.1 ISSN : 1063-6536 En ligne : http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=5169845