# Improved Representation of Dependencies in Feature-based Parametric CAD Models using Acyclic Digraphs

### Jorge D. Camba, Manuel Contero

#### Abstract

In an engineering design context, the process of modeling complex 3D parts with feature-based parametric software systems often produces a large number of dependencies between geometric features that are difficult to manage. The resulting network of feature interdependencies can be understood as an alternative representation of the CAD model that can help identify the most important aspects of the geometry, its critical features, and understand the overall complexity and interconnectedness of the model. Being able to visualize and process this information efficiently can significantly enhance design activities and facilitate model reuse, which can ultimately lead to cost and time savings, and better quality models. In this paper, we identify some of the simplifications and elements that are overlooked by current representation techniques and describe the negative consequences of not taking these elements into consideration. We describe a new method and a software solution to generate a simplified, intuitive, and more accurate visualization of a parametric model as an acyclic digraph. Finally, to validate our approach, the proposed representation is compared to existing techniques using a group of CAD models.

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#### Paper Citation

#### in Harvard Style

Camba J. and Contero M. (2015). **Improved Representation of Dependencies in Feature-based Parametric CAD Models using Acyclic Digraphs** . In *Proceedings of the 10th International Conference on Computer Graphics Theory and Applications - Volume 1: GRAPP, (VISIGRAPP 2015)* ISBN 978-989-758-087-1, pages 16-25. DOI: 10.5220/0005261500160025

#### in Bibtex Style

@conference{grapp15,

author={Jorge D. Camba and Manuel Contero},

title={Improved Representation of Dependencies in Feature-based Parametric CAD Models using Acyclic Digraphs},

booktitle={Proceedings of the 10th International Conference on Computer Graphics Theory and Applications - Volume 1: GRAPP, (VISIGRAPP 2015)},

year={2015},

pages={16-25},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0005261500160025},

isbn={978-989-758-087-1},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the 10th International Conference on Computer Graphics Theory and Applications - Volume 1: GRAPP, (VISIGRAPP 2015)

TI - Improved Representation of Dependencies in Feature-based Parametric CAD Models using Acyclic Digraphs

SN - 978-989-758-087-1

AU - Camba J.

AU - Contero M.

PY - 2015

SP - 16

EP - 25

DO - 10.5220/0005261500160025