Blowing machine for wind musical instrument : toward a real-time control of the blowing pressure

Blowing machines were developed since the early stage of research in musical acoustics because they are necessary for the study of musical instruments. The system under study is based on a previously developed blowing machine dedicated to the study of the physics of wind instruments (trumpet, reed instruments, recorder) for which the blowing pressure was tuned by hand through a manometer. In this paper, the blowing machine is connected to pressured air through a servo-valve driven from a computer within a closed loop according to a (possibly) time-varying target pressure. The system being non linear, a robust controller has been implemented (PID + gain scheduling + feedforward) with step response performances reaching up to 5 ms to 10 ms.