Fourier Transform in Making Noise-less Appliances

Most electric appliances such as washing machines, refigerators, and dishwashers make noise and vibrations when on use. Manufacturers are trying to eliminate this problem. However, it is necessary to know the natural frequencies of vibrated system in order to make measures to reduce the vibrations. One way to accomplish this is recording sound to a digital file and transforming the data by the Fast Fourier Transformation.

This is expounded in this paper: