Analysis of periodic information in a signal
First Claim
1. A method for analyzing periodic information in a signal associated with a machine or process, the method comprising:
- (a) acquiring the signal over a time period using a sensor associated with the machine or process;
(b) generating an autocorrelation waveform based on the signal;
(c) determining a periodic signal parameter value based at least in part on the autocorrelation waveform, the periodic signal parameter value comprising a single real number indicative of a level of periodic information in the signal;
(d) determining a vibration waveform value based on the signal;
(e) comparing the vibration waveform value to a vibration waveform value threshold;
(f) comparing the periodic signal parameter value to a periodic signal parameter value threshold; and
(g) generating an output indicating a no-fault condition of the machine or process if the vibration waveform value is less than the vibration waveform value threshold and the periodic signal parameter value is less than the periodic signal parameter value threshold.
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Accused Products
Abstract
A “periodic signal parameter” (PSP) indicates periodic patterns in an autocorrelated vibration waveform and potential faults in a monitored machine. The PSP is calculated based on statistical measures derived from an autocorrelation waveform and characteristics of an associated vibration waveform. The PSP provides an indication of periodicity and a generalization of potential fault, whereas characteristics of the associated waveform indicate severity. A “periodic information plot” (PIP) is derived from a vibration signal processed using two analysis techniques to produce two X-Y graphs of the signal data that share a common X-axis. The PIP is created by correlating the Y-values on the two graphs based on the corresponding X-value. The amplitudes of Y-values in the PIP is derived from the two source graphs by multiplication, taking a ratio, averaging, or keeping the maximum value.
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Citations
9 Claims
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1. A method for analyzing periodic information in a signal associated with a machine or process, the method comprising:
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(a) acquiring the signal over a time period using a sensor associated with the machine or process; (b) generating an autocorrelation waveform based on the signal; (c) determining a periodic signal parameter value based at least in part on the autocorrelation waveform, the periodic signal parameter value comprising a single real number indicative of a level of periodic information in the signal; (d) determining a vibration waveform value based on the signal; (e) comparing the vibration waveform value to a vibration waveform value threshold; (f) comparing the periodic signal parameter value to a periodic signal parameter value threshold; and (g) generating an output indicating a no-fault condition of the machine or process if the vibration waveform value is less than the vibration waveform value threshold and the periodic signal parameter value is less than the periodic signal parameter value threshold. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
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Specification