Automatic CAD Models Comparison and Re-meshing in the Context of Mechanical Design Optimization

Abstract

A lot of research work has been focused on integrating FEA (finite elements analysis) with CAD (Computer Aided Design) over the last decade. In spite of improvements brought by this integration, research work remains to be done in order to better integrate all the operations led during the whole design process. The design process involves several modifications of an initial design solution and until now, in this context, the communication between CAD modules (dedicated to different tasks involved in the product design process) remains static. Consequently, there is a need for more flexible communication processes between CAD modules through the design cycle, if not through the product life cycle. Some approaches have been developed aiming at the reduction of the design process length when using FEA, and aiming at the automation of part’s data transfer from one step of the process to the next one. Automatic re-meshing is one of these approaches. It consists in automatically updating the part’s mesh around modifications zones, in the case of a minor change in the part’s design, without the need to re-mesh the entire part. The purpose of this paper is to present a new tool, aiming at the improvement of automatic re-meshing procedures. This tool basically consists in automatically identifying and locating modifications between two versions of a CAD model (typically an initial design and a modified design) through the design process. The knowledge of these modifications is then used to fit portions of the initial design’s mesh to the modified design (a process referred to as automatic re-meshing). A major benefit of the approach presented here is that it is completely independent of the description frame of both models, which is made possible with the use of vector-based geometric representations.