Experimental study of real gear transmission defects using sound perception

Abstract

The aim of this paper is to study gear defects able to appear on rotating machines using sound perception. To assimilate a real gear defect, the experimental setup was left operating under given load during several days. Measurements have been taken each 2 h on the input and output shafts. Acoustic sounds are performed using the processing software «DynamX V.7». These sounds are analyzed with the paired comparison method to find a correlation between the sounds perception and the scalar indicators. The results show that perception tests allowed classifying gear defect sounds in degradation order. The correlation between objective and subjective aspects highlights an important relationship between scalar indicators (kurtosis, Crest Factor, the spectral center of gravity SCG and the root mean square RMS) and the difference between gear sounds characterized by the sounds distance in the proximity space. Vibratory analysis is also performed to follow up the gear degradation state and to confirm sound perception results obtained from the proposed approach.