An algorithm to diagnose ball bearing faults in servomotors running arbitrary motion profiles

This paper describes a procedure to extend the scope of classical methods to detect ball bearing faults (based on envelope analysis and fault frequencies identification) beyond their usual area of application. The objective of this procedure is to allow condition-based monitoring of such bearings in servomotor applications, where typically the motor in its normal mode of operation has to follow a non-constant angular velocity profile that may contain motion inversions. After describing and analyzing the algorithm from a theoretical point of view, experimental results obtained on a real industrial application are presented and commented.

► Diagnostics of the supports of servomotors for maintenance.
► Servomotors follow non-constant angular velocity profiles.
► Selection of an opportune sampling angular period respect to the shaft motion law.
► For high resolution analysis merging of all the processed signal parts.
► For low resolution analysis computing of the Fourier transform of the signal parts.