The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 27, 2001
Filed:
Dec. 21, 1999
David A. Jackson, Los Gatos, CA (US);
Hoshang Shroff, Cupertino, CA (US);
Donald J. Christian, Fremont, CA (US);
Stephen Glickman, Los Gatos, CA (US);
Snap-On Technologies, Inc., Lincolnshire, IL (US);
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 that degrades performance beyond a preset tolerance, the fault is flagged for attention and a suggested corrective action is displayed.