STATISTICAL TREND GENERATOR FOR PREDICTIVE INSTRUMENT MAINTENANCE

摘要

A method for adaptively scheduling maintenance of a sensor (14) infers the need for maintenance of that sensor on the basis of an error signal indicative of a difference between a measurement signal generated by that sensor and an independently obtained reference signal that is correlated with the measurement signal (16). Although the reference signal is not identical to the measurement signal, the correlation between these two signals assures that when the sensor is functioning, the two signals will track each other over time. The disclosed method includes the step of generating this error signal and then monitoring that error signal to detect a triggering event indicative of a mismatch between the reference signal and the measurement signal. This mismatch is indicative of a probability that there exists a malfunction in the sensor. The value of this probability depends on the choice of the triggering event.