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A Knowledge-Navigation System for Dimensional Metrology



Howard T. Moncarz


Geometric dimensioning and tolerancing (GD&T) is a method, based on dimensional metrology, to specify a part so that it will meet its design intent. GD&T is difficult to master for two main reasons. First, it is based on complex 3D geometric entities and relationships. Second, the geometry is associated with a large, diverse knowledge base (of dimensional metrology) with many interconnections.This paper describes an approach to create a dimensional metrology knowledge base that is organized about a set of key concepts and to represent those concepts as virtual objects that can be navigated with interactive, computer visualization techniques to access the associated knowledge.The approach can enable several applications. First is the application to convey the definition and meaning of GD&T over a broad range of tolerance types. Second is the application to provide a visualization of dimensional-metrology knowledge within a control hierarchy of the inspection process. Third is the application to show the coverage of interoperability standards to enable industry to make decisions on standards development and harmonization efforts.A prototype was implemented to demonstrated the principles involved in the approach.
Journal of Research (NIST JRES) -
107 No. 2


dimensional metrology, dismensioning and tolerancing, knowledge navigation, manufacturing training, VRML


Moncarz, H. (2002), A Knowledge-Navigation System for Dimensional Metrology, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD (Accessed June 21, 2024)


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Created April 1, 2002, Updated February 17, 2017