Adaptive high frequency energy detection

Abstract

A data collector having a digital signal processing circuit that receives a digitized vibration signal, and performs processing steps to isolate high frequency pulses in the digitized vibration signal and quantify energy content of those pulses by detecting a peak negative value of the digitized peak-to-peak amplitude of the received vibration signal, and then using this peak negative value to compute a maximum peak-to-peak value of the received vibration signal. Periodically, the maximum peak-to-peak value and peak negative value are reduced in magnitude by a decay factor, such that the peak negative value and maximum peak-to-peak value decay over time. The decay factors used in computing the maximum peak-to-peak value and peak negative value are determined by the digital signal processing circuit and may be readily changed. As a consequence, high frequency processing performed by the digital signal processing circuit may be readily adapted to the particular frequency characteristics of the machine being analyzed for predictive maintenance, without modification of the analog circuitry of the data collector. The resulting maximum peak-to-peak value comprises a peak-detected digital output signal that may be stored and/or displayed to a user as a reflection of the high frequency content of the vibration signal, or frequency transformed for storage and/or display to a user.