Geometric and form feature recognition tools applied to a design for assembly methodology

Abstract

The paper presents geometric tools for an automated Design for Assembly (DFA) assessment system. For each component in an assembly a two step features search is performed: firstly (using the minimal bounding box) mass, dimensions and symmetries are identified allowing the part to be classified, according to DFA convention, as either rotational or prismatic; secondly form features are extracted allowing an effective method of mechanised orientation to be determined. Together these algorithms support the fuzzy decision support system, of an assembly-orientated CAD system known as FuzzyDFA.

Design and implementation of an integral design CAD system for plastic profile extrusion die

“…After finding the personal best and global best values, velocities v ij t and positions x ij t of each particle are updated by Eqs. (13) and (14).…”

“…Coma et al presented an automatic feature shape recognizer tool for a design for assembly (DFA) methodology [13]. Hermansson et al proposed a novel approach to automatic adaptation of assembly models based the recognition of relevant elements between components [14].…”

What are features? An ontology-based review of the literature

“…The table is neither an exhaustive list of the variety of categories proposed, nor shows the relationships between these categories. Assembly features, for instance, are sometimes conceived only from a geometric perspective [43,51], while in some other cases their description is enriched with manufacturing details [52,53,54]. Currently, there is no shared methodology for feature classification, as it depends on application requirements and scenarios; doubts have also been raised about the possibility of an exhaustive categorisation of all feature types [28,7].…”

Interfacing product views through a mixed shape representation. Part 2: Model processing description

“…b illustration of the mapping function between the input and output polyhedrons as defined through the global parameterization scheme and the vertex removal operator transformation operates locally, therefore if a mapping already exists between the shape input in the PV Interface in the current one when the targeted vertex need to be removed, the mapping between them needs to be modified only for the set of faces being removed with the candidate vertex. Indeed, this configuration is equivalent to a configuration where a global parameterization of a polyhedron is needed [3,4,11]. Much work has been performed on that topic in the field of computer graphics for transferring textures, computing normal maps to improve rendering, .…”