Method and apparatus of automatically identifying faults in a machine vision measuring system
US6323776A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 21, 1999 |
| Grant date | Nov 27, 2001 |
| Priority date | — |
| Expiry date | Dec 21, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P90/02
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus and method for automatically identifying faults in the operation of a machine vision measuring systems provides an improved self-diagnostic capability for machine vision based metrology and tracking systems. The method and apparatus validate performance of tracking operations, and detect deterioration that may be caused by electronic noise, environmental contamination, etc. A mathematical model of the target visualized by the system is created and stored. A target is imaged in the field and fiducials of the target are identified. Centroid positions of detected fiducials of the imaged target are compared to the centroid positions of fiducials in the mathematical model. When a fiducial is obscured or dirty, its geometric characteristics (such as centroid, brightness, edge smoothness, area, or shape) differ from the true or idealized values of the characteristics. Values representing detected fiducials are discarded when the offset exceeds predetermined criteria, or when its properties vary from ideal. If the remaining number of detected fiducials is below a predetermined threshold, a warning message is displayed or an error is generated. Thus, when a fault is detected th…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.