Currently devices equipped with self-diagnostic capabilities are limited to measuring simple discrete events: on / off, working / not working, machine cycle completed in time or out of time.
Why not try to measure the actual conditions that underlie these events, such as, for example, the degree of wear of a component? It would allow employees to establish the most likely time for component breakage with the consequent possibility of requesting the intervention of a service technician before the machine stops working.
Researchers from Xerox Corporation are engaged in developing a technique called Signature Analysis (SA). It is an automatic procedure based entirely on unique and easily identifiable analog signals – noise, vibration or load – which characterize the operation of motors and other electromechanical devices. Basically, each component transmits a signal represented by a waveform. By comparing this signal with the waveforms characteristic of optimal operation and with those typical of the approach of breaking conditions, it is therefore possible to calculate the life expectancy of the component.
The SA procedure has found its first application in heavy industry, where it is used as a diagnostic tool by maintenance workers of equipment such as electric turbines and industrial machinery. In the mid-1990s, Xerox extended the use of this technique to the smaller and less expensive components of printers and copiers. Indeed, Xerox researchers discovered that the SA procedure could be used profitably in reconditioning operations to separate reusable components from those to be reconditioned or disposed of, with the result of ensuring superior reliability of the products and reducing the quantity of materials to be disposed of. .
Bob Siegel, from Webster's Xerox center, engaged together with the designers in a program aimed at integrating SA technology into the new generations of Xerox systems, who will therefore be able to self-diagnose their problems. By analogy, as if in medicine it was possible to detect an anomaly in an electrocardiogram even before the doctor suspects that the patient may have a partially obstructed artery.
Xerox has a solid tradition of products capable of remotely communicating the existence of a problem to a central database, which in turn can send a service technician before the printer or copier stops working. Until now it has been possible to measure digital data relating to discrete events, data which are essentially the product of the underlying analog processes. Through the integration of digital data with the analog "signatures" of the components, Xerox will be able to predict the malfunctions and the end of the useful life of the components. Result: less downtime for customers and reduced service costs, thanks to the possibility for technicians to replace components only when actually necessary and not based on the simple counting of the printed pages in a certain period of time.
SA will also be incorporated into all test devices used in the manufacture of new generation Xerox production printers.