Exchange of Parametric Curve and Surface Geometry Between Computer Aided Design Systems

  • M. J. Pratt
  • R. J. Goult
  • M. A. Lachance
Part of the European Consortium for Mathematics in Industry book series (ECMI, volume 6)


The transfer of geometric data between dissimilar computer aided design (CAD) systems is a problem of great concern to manufacturing industry. It arises when a single organisation uses different systems at different stages of the design/ manufacturing cycle, and also in contractor/subcontractor situations where the two organisations do not use the same system. In either case it is clearly preferable to transfer the data on magnetic tape and have it read automatically than to generate drawings using the sending system and to re-enter them manually into the receiving system. However, different CAD systems use different internal formats for data storage, and the idea of a ‘neutral format’ has arisen to facilitate the interchange. In a draughting context, for example, such a medium provides a neutral, system-independent, means for representing lines, circular arcs and various types of annotation commonly used on drawings. Native information from the sending system is written in this form by a translator known as a preprocessor. A postprocessor is then required to translate the neutral file data into the native internal format of the receiving system.


Chebyshev Polynomial Parametric Curve Subdivision Strategy Surface Geometry Spline Curve 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© B.G. Teubner Stuttgart and Kluwer Academic Publishers 1991

Authors and Affiliations

  • M. J. Pratt
    • 1
  • R. J. Goult
    • 1
  • M. A. Lachance
    • 1
  1. 1.Department of Applied Computing & MathematicsCranfield Institute of TechnologyCranfieldBedford MK43 OALEngland

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