Analyzing and Optimizing Constraint-Structures in Complex Parametric CAD Models

Abstract

CAD-modelers have made a change from simple modelers of part geometry to sophisticated applications for representation and presentation of digital mock-ups (DMUs) of complex products. Paradigms like assembly modeling or design by features are common practice. Parametric modelers, that do not only model a product’s static structure but also try to keep the intent of a design by constraints or even derive the geometry of a part as a variant of a series of parts based on a constraint representation, are the state of the art. The designer who has to use these applications is confronted with an overwhelming functionality, giving him the possibility to represent almost all of his design decisions in the CAD model in different, more or less structured or comprehensible ways. Along with this progress in functionality the models created with these applications have become more and more complex. The development of functionality that supports the designer or even a team of designers and other users to understand, document, modify or reuse complex models has not kept track with the development of modeling functions. The presented work aims at providing this functionality by developing methods and tools for the analysis and optimization of structures of complex parametric CAD models. The state of the art of structuring and analyzing functionality within constrained CAD models is discussed and methods for the optimization of constraint-structures within CAD-models as well as for the analysis and comprehensible presentation of constraint-structures are introduced. Moreover a prototype system providing analysis functionality based on the proposed methods is presented.