Supervision: Hervé Lissek
Project type: Semester project (bachelor)
Available
The Electroacoustic Absorber (EA) concept relies on a closed-box loudspeaker, the membrane of which can be assigned a prescribed acoustic impedance thanks to a microphone-based active feedback control. Once set, the acoustic performance of the EA is usually assessed in an impedance tube following ISO 10534-2 standard (assuming plane waves, two microphones allow separating the forward and backward sound propagation coefficients, and then the reflection/absorption coefficients or the acoustic impedance of the membrane).
The project proposes a journey into the wonderful world of EAs, by first understanding the principle of direct impedance control in Matlab, and then by implementing the active control on an actual prototype with a Speedgoat Real-Time Target Machine (interfaced through Matlab/Simulink). Since the same hardware can be used also for real time measurement (not only control), this makes it a very useful tool for acoustic manipulation (control) and measurements.
After being initiated to the concept and to the Speedgoat programming, the student will deliver a stand-alone Graphical User Interface allowing an unexperimented user manipulate and assess any EA without prior knowledge.
The project will consist of:
- literature review on Electroacoustic Absorbers
- development of an analytical model (Matlab) of an EA
- development of a control interface on Simulink for Speedgoat
- experimental set-up to characterize the performance of the EA in an impedance tube
- development of a GUI allowing modifying the control parameters and perform the acoustic assessement
Profile: Electrical engineering
Prerequisites: Electroacoustics
Learning outcome: active control in acoustics, acoustic measurement, Speedgoat programming
Context: Theory/Physical Simulations (30%), measurement (30%), Matlab programming (40%)