Antoine FALAIZE will defend his PhD work entitled:
“Modeling, Simulation, Code Generation and Correction of Multi-Physical Audio Systems: Approach by Network of Components and Port-Hamiltonian Formulation”
This work took place in the Project-Team Sound Signals and Systems and in the Analysis-Synthesis team of Laboratoire Sciences et Technologies de la Musique et du Son, IRCAM-CNRS-UPMC under the supervision of Thomas Hélie (Researcher, UMR STMS, IRCAM).
It is part of the ANR (French National Research Agency) project: ANR-HamecMopsSys.
This work will be defended to the following jury:
- M. Stefan Bilbao - Rapporteur, Professeur, Acoustics and Audio Group, Edinburgh University
- M. Pierre Rouchon - Rapporteur, Professeur, Centre Automatique et Systèmes, Mines-ParisTech
- M. Benoît Fabre - Examinateur, Professeur, Équipe Lutherie Acoustique Musique, IJLRA, Université Paris 6
- M. Yann Le Gorrec - Examinateur, Professeur, École Nationale Supérieure de Mécanique et des Microtechniques, FEMTO-ST/AS2M
- M. Aziz Hamdouni - Examinateur, Professeur, Laboratoire des Sciences de l’Ingénieur pour l’Environnement, Université de La Rochelle
- M. Hervé Lissek - Examinateur, Professeur, LTS2, École Polytechnique Fédérale de Lausanne
The class of audio systems includes traditional musical instruments (percussion, string, wind, brass, voice) and electro-acoustic systems (guitar amplifiers, analog audio processing, synthesizers). These multi-physical systems have a common property: out of excitation sources (generators), they are all passive. We present a set of automatic methods dedicated to their modeling, simulation and control, which explicitly guarantee and exploit the passivity of the original system. This class of systems is that of port-Hamiltonian systems (PHS), introduced in system theory in the early 1990s.
Regarding the models, we exploit the fact that the interconnection of systems described in this formalism explicitly preserves the dynamics of total dissipated power. This enabled the development of an automated method that builds models of complete instruments based on a dictionary of elementary models.
Regarding the simulations, we developed a numerical method that preserves the passive structure of PHS in discrete-time domain. This ensures the stability of simulations (for which the C++ code is automatically generated).
Regarding the control, we exploit the interconnection structure to automatically build an input-to-output decoupled form for a class of PHS. Systems of this class are flat, within the meaning of the differential flatness approach. A formula that yields the (open loop) control law for these systems is provided.