A multi-objective optimization procedure for guiding the active sound quality control of multi-harmonic disturbances in cavities

The refinement of the sound quality of the engine disturbance perceived in vehicle cavities can be accomplished by means of active control algorithms, oriented by psychoacoustic metrics. Loudness, Roughness and Tonality, as the most regarded metrics in designing sound quality targets for low frequency disturbances, are commonly investigated on an individual basis, which leads to tackle one or some of them, while -possibly- degrading the others. This paper contributes to the design and implementation stages of the sound quality for low-frequency, multi-harmonic disturbances by presenting a multi-objective optimization procedure. The optimization tools correspond to the NSGA-II and SPEA-II algorithms, which have been extensively used in the engineering community for solving problems with conflictive objectives, as is the Loudness/Roughness/Tonality case and its combinations by pairs. Both the NSGA-II's and SPEA-II's operators and parameters are selected from the specialized literature. Computer simulations of the SF-cFxLMS control algorithm implemented over a synthesized internal combustion engine disturbance show the feasibility of attaining the obtained Pareto frontier solutions, thus demonstrating a complete method for controlled designing and implementing of sound fields in cavities.