ETD

Archivio digitale delle tesi discusse presso l'Università di Pisa

Tesi etd-11242008-231134


Tipo di tesi
Tesi di dottorato di ricerca
Autore
PANESI, RENATO
URN
etd-11242008-231134
Titolo
H_infinity Loop-Shaping Control of Aerospace Systems
Settore scientifico disciplinare
ING-IND/03
Corso di studi
INGEGNERIA AEROSPAZIALE
Relatori
Relatore Prof. Mengali, Giovanni
Parole chiave
  • multivariable
  • loop-shaping
  • H_infinity
  • control
  • robust
  • singular values
Data inizio appello
01/12/2008
Consultabilità
Completa
Riassunto
Loop-Shaping design with H_infinity controller synthesis plays a role of primary importance for the synthesis of robust multi-variable controllers. However, a typical difficulty is that
the designer has to develop considerable expertise in this matter before obtaining good results. In fact, the choice of the weighing matrices, that are at the heart of the loop-shaping design, is not an easy issue.
The aim of the work described in this dissertation is to improve the well known H_infinity loop-shaping approach, by simplifying the shaping procedure and by extending its range of effectiveness, through some useful additions helping the designer in the controller synthesis.
The first major improvement consists in the definition of a scaling method aiming to minimize the condition number of the plant. This simplifies the choice of weights and increases the closed-loop robustness.
A second important addition is the development of a design procedure helping the designer in the selection of non-diagonal weights, which seems the best solution to overcome difficulties related to plants with highly coupled dynamics.
A Matlab software package has been created, which implements the proposed design procedures and assists the designer by simplifying the shaping activity and reducing his/her amount of work.
The exposed design methodologies are validated through some case studies, where typical problems of flight control system design are dealt with. These applications are illustrated with the aid of a Matlab/Simulink linearized model of an aircraft.
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