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CIRP Encyclopedia of Production Engineering pp 737–743Cite as

Freeform

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Synonyms

Complex geometry; Freeform metrology; Freeform optics

Definition

Freeform is where the surface shape has no continuous translational or rotational symmetry about axes. Freeform surfaces belongs to the class of complex invariant surfaces (ISO 17450-1 2011).

Theory and Application

Introduction

Freeform surface is becoming ubiquitous in industrial products, either for functional or aesthetical reasons. The geometry of freeform surfaces cannot be described by a single universal equation and it has a great influence on the performances of a product (Jiang and Whitehouse 2012). Many types of surfaces are defined as freeform by industry: e.g., off-centred rotational optics, toroidal, etc. These are mathematically not true freeform surfaces but they do have an axis, however this axis does not pass through the functional surface. What follows is also applicable to these quasi-freeform surfaces. Here there are described two types of freeform applications: freeform optics (see Fig. 1)...

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References

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Author information

Authors and Affiliations

  1. Centre for Precision Technologies, University of Huddersfield, Huddersfield, UK

    Xiangqian Jiang

Authors
  1. Xiangqian Jiang
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Corresponding author

Correspondence to Xiangqian Jiang .

Editor information

Editors and Affiliations

  1. National Engineering School of Monastir (ENIM), University of Monastir, Monastir, Tunisia

    Sami Chatti

  2. Mechanical Engineering, Université du Québec à Trois-Rivières, Trois-Rivières, QC, Canada

    Luc Laperrière

  3. Institute for Machine Tools and Industrial Management (iwb), Technical University of Munich (TUM), Garching, Germany

    Gunther Reinhart

  4. ITIA Institute of Industrial Technologies and Automation, CNR National Research Council, Milan, Italy

    Tullio Tolio

Section Editor information

  1. Mitutoyo RCE, Best, The Netherlands

    Han Haitjema

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Cite this entry

Jiang, X. (2019). Freeform. In: Chatti, S., Laperrière, L., Reinhart, G., Tolio, T. (eds) CIRP Encyclopedia of Production Engineering. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-662-53120-4_16854

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