Vol.3, No 15, 2003 pp.1033-1038
UDC 681.5.01+62-52
Invited Paper

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CONTROLLER DESIGN
FOR A FUNNEL-SHAPED SMART SHELL STRUCTURE
Tamara Nestorović Trajkov^1,2
Ulrich Gabbert¹, Heinz Köppe^1
1Otto-von-Guericke-Universität Magdeburg, Fakultät für Maschinenbau,
Institut für Mechanik, Universitätsplatz 2, D-39106 Magdeburg, Germany
²Faculty of Mechanical Engineering, University of Niš
Aleksandra Medvedeva 14, 18000 Niš, Serbia and Montenegro

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Abstract.The paper is aimed at controller design for the vibration suppression of a funnel-shaped shell structure, which is a part of a complex medical device – magnetic resonance tomograph. Control and sensing are achieved with piezoelectric actuators and sensors attached to the surface of the funnel. State space model of the structure is developed applying the modal analysis and reduction of the finite element model order. Optimal LQ controller combined with tracking system based on additional dynamics is designed. As an alternative for the controller design a direct robust model reference adaptive control is proposed. Both controllers perform considerable vibration suppression in comparison with uncontrolled case.

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PROJEKTOVANJE UPRAVLJANJA ZA AKTIVNU KONSTRUKCIJU TIPA LJUSKE U OBLIKU LEVKA U radu je prikazano projektovanje kontrolera za redukciju oscilacija aktivne konstrukcije tipa ljuske u obliku levka, koja predstavlja deo složenog medicinskog uređaja, magneto-rezonantnog tomografa. Upravljanje je realizovano pomoću piezoelektričnih aktuatora i senzora pričvršćenih za površinu levka. Model u prostoru stanja dobijen je na osnovu modela konačnih elemenata primenom modalne analize i redukcije reda modela. Projektovani kontroler je optimalni LQ sistem praćenja sa dodatnom dinamikom. Kao alternativa za projektovanje upravljanja predložen je direktni robustni adaptivi algoritam sa referentnim modelom. Primenom oba projetovana upravljačka zakona uočava se značajna redukcija oscilacija levka u poređenju sa slučajem bez upravljanja.