Integrated Dimensional Variation Management in the Digital Factory


J E Muelaner, P G Maropoulos
Department of Mechanical Engineering, The University of Bath, Bath, UK

Published in

Proceedings of DET2011 7th International Conference on Digital Enterprise Technology, Athens, Greece, 2011

Volume and page number information



This paper describes how dimensional variation management could be integrated throughout design,
manufacture and verification, to improve quality while reducing cycle times and manufacturing cost
in the Digital Factory environment. Initially variation analysis is used to optimize tolerances during
product and tooling design and also results in the creation of a simplified representation of product
key characteristics. This simplified representation can then be used to carry out measurability
analysis and process simulation. The link established between the variation analysis model and
measurement processes can subsequently be used throughout the production process to
automatically update the variation analysis model in real time with measurement data. This ‘live’
simulation of variation during manufacture will allow early detection of quality issues and facilitate
autonomous measurement assisted processes such as predictive shimming.

A study is described showing how these principles can be demonstrated using commercially
available software combined with a number of prototype applications operating as discrete modules.
The commercially available modules include Catia/Delmia for product and process design, 3DCS
for variation analysis and Spatial Analyzer for measurement simulation. Prototype modules are used
to carry out measurability analysis and instrument selection. Realizing the full potential of
Metrology in the Digital Factory will require that these modules are integrated and software
architecture to facilitate this is described. Crucially this integration must facilitate the use of realtime
metrology data describing the emerging assembly to update the digital model.



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Integrated Digital Variation Management
Integrated Digital Variation Management


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