Analysis and Classification of Air Disc Brake Sounds in Time and Frequency Domain

In this study, analysis and classification of audio data collected from faulty air disc brakes has been carried out by Fourier Transform (FT). The sound data have been recorded by 2 identical Norsonic Type 1228 microphones in the laboratory of Ege Fren A.S. on a vehicle. The recorded data set which has been transferred into computer by a data acquisition board has been analyzed in Matlab. Number of zero crossings; mean, variance, entropy, and spectral rolloff of Fourier coefficients have been used as features in order to distinguish normal and faulty brakes. These features have been classified with 10x10 crossvalidation by using kth nearest neighbour algorithm with a success rate of 96.23