@article {ipa|Identification of patterns of repeated parts in solid objects|2016,
	title = {Identification of patterns of repeated parts in solid objects},
	year = {2016},
	month = {November},
	pages = {128 p.},
	institution = {CNR-IMATI},
	address = {Genova},
	abstract = {<p>The feature-based modeling approach for designing a mechanical component has been widely adopted by most CAD modelers to maintain the design intent on models. A set of higher level information is requested to enrich the usual geometrical and topological data, in terms of feature information. A well known example of semantically significant data of this type is represented by the knowledge of the existence of symmetrical arrangements of repeated subparts in CAD models. Because of the information transferring, repeated modifications of the models and different tolerances used by the various CAD systems, these specific data can be lost. In this report, after having provided the necessary mathematical background and the state of art of the existing symmetry detection methods, we propose an approach for retrieving symmetries involving a set of user-selected sub-parts in a given BRep part model. The approach is based on a preliminary analysis of the position of points (centroids), each of them representing one repeated feature; a further examination on the faces of the sub-parts is performed to confirm the existence of symmetric arrangements. We have provided the description for the detection of linear translational, reflectional, and circular translational patterns of repeated sub-parts.</p>
},
	keywords = {shape analysis},
	url = {http://irs.imati.cnr.it/reports/irs16-14},
	author = {L. Chiang and F. Giannini and M. Monti}
}
@article {ipa|Identification of patterns of repeated parts in solid objects - Part II|2016,
	title = {Identification of patterns of repeated parts in solid objects - Part II},
	year = {2016},
	month = {November},
	pages = {54 p.},
	institution = {CNR-IMATI},
	type = {Working paper},
	address = {Genova},
	abstract = {<p>The work described in this report extends the methods described in the report "Identification of Patterns of Repeated Parts in Solid Objects" ([2]) to deal with CAD assemblies and to the detection of additional types of patterns. Specifically rotational and compound patterns of repeated elements are treated. Therefore, references of all notations, definitions and terms of the objects cited in this report can be found in [2]. The Chapter 1 describes the proposed approach to detect rotational patterns of repeated entities in part model, extending the set of types of patterns considered in [1], [2]. Chapter 2 contains the method proposed for assembly models for the detection of symmetric arrangements on components, considering as repeated elements of the patterns the instances of a part or assembly file. Chapter 3 is dedicated to the introduction of the concept of compound pattern, intended as an improvement of the quality of the symmetry information of a model, obtained by combining the information referred to the patterns of repeated elements. The approach has been described and provided either for part and assembly models.</p>
},
	keywords = {shape analysis},
	url = {http://irs.imati.cnr.it/reports/irs16-15},
	author = {L. Chiang and F. Giannini and M. Monti}
}
