An acoustic model to control an experimental slide flute

Brigitte d'Andréa-Novel (1) , Benoît Fabre (2) , Jean-Michel Coron (3)

1 CAOR - Centre de Robotique
2 DALEMBERT - Institut Jean Le Rond d'Alembert
3 LJLL - Laboratoire Jacques-Louis Lions

We consider the problem of modeling and control of a slide flute: a kind of recorder without finger holes but ended by a piston to modify the length of the resonator. To control dynamical systems, it is important to elaborate a realistic model, so that control laws can be tested efficiently before they are implemented on real size prototypes. The dynamical model we have elaborated takes into account the coupling effects between the jet and the pipe which is a linear acoustic resonator. The jet is obtained by blowing through a flue channel and formed by flow separation at the flue exit, and finally directed towards a sharp edge, called the labium. A modal analysis is then performed using the linearized boundary conditions to compute the suitable blowing pressure and the suitable pipe length to obtain a desired pitch. This will constitute the "feedforward" part of our control algorithm. The Proportional-Integral feedback term is then elaborated to regulate the system to the desired set point, using the length of the piston measured by an encoder and the blowing pressure measured by a pressure sensor. First experimental results, obtained on a "mechatronic" prototype developed at Mines ParisTech will be presented.

Mots clés: Acoustic modeling; slide flute; control; experimentations

Domaines: Acoustique [physics.class-ph]

Brigitte d'Andréa-Novel, Benoît Fabre, Jean-Michel Coron. An acoustic model to control an experimental slide flute. Acoustics 2012, Apr 2012, Nantes, France. ⟨hal-00810702⟩