EVALUATION OF VIBROACOUSTIC DIAGNOSTIC SYMPTOMS BY MEANS OF THE ROUGH SETS THEORY

Vibroacoustic symptoms used in technical diagnostics of mechanical objects are considered. In particular, a comparison of different methods defining symptom limit values is carried out. Symptoms limit values divide domains of symptoms into intervals which correspond to classes of technical states of considered objects. A new approach based on the rough sets theory was employed to perform this comparison. In consequence, a method giving the best definition of symptom limit values, in the sense of the most accurate diagnosis of the objects, was found out. The diagnostic investigation was done on data from a set of rolling bearings. The data were collected in a real industrial environment. So, in addition, the obtained results were compared with results of a similar investigation done in laboratory conditions.