Method for isolating sources of drifts in output properties for machines and processes
US7174283B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 8, 2002 |
| Grant date | Feb 6, 2007 |
| Priority date | — |
| Expiry date | Nov 9, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05B23/0281
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A method for determining a root cause for a drift in a process or a machine, the function of which is determined by a model describing a relationship between setup and/or input variables and output property or properties, comprising the steps of: (a) Assigning desired output properties for a product of said machine or process, and allowed ranges for said properties; (b) Assigning original values to said variables for obtaining by said machine or process said assigned output properties within said assigned ranges; (c) Measuring the various output properties of the machine or process; (d) When measuring an output property of the machine or process that drifts from its assigned value, substituting the one or more measured output properties in their corresponding model equations, and calculating for each variable in each equation its presumed value, assuming it is the sole cause of the drift; and (e) Analyzing all presumed calculated variable values and the measured values of the output properties of the machine or process to determine the variable that is most probably responsible for the drift.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.