A multi-probe setup for the measurement of angular vibrations in a rotating shaft

In this paper we discuss a measurement method based on the zero-crossing demodulation method of FM signals to estimate the angular velocity vibrations of a rotating shaft. The demodulation algorithm is applied without any filtering to the direct output voltage of probes sensing the tooth passing of a geared wheel installed on a rotating shaft. The proposed method rejects the effects on the measurements due to the irregular cogwheel shape profile.