Patent ID: 6281803
Filing Date: 2001-08-28
Classification: G01R

Abstract:
A control mat monitoring apparatus comprising:a) means for developing an electronic signal value proportional to the time-varying value of the electrical resistance of a control mat in the course of normal use,b) means for continuously recording and updating the statistical distribution of the value of said electronic signal value, said statistical distribution having upper and lower limits and other characteristic statistical features generally evolving with time,c) means for generating a detection signal based on the dynamic relationship of, and between, said electronic signal value and said evolving upper and lower limits of said statistical distribution, andd) means for generating a mat failure warning signal based on said evolving characteristic statistical features of said statistical distribution,whereby a detection signal is generated in a manner that compensates dynamically for changes in the electrical resistance characteristics of said control mat and a timely warning is provided of pending mat failure.