Design Rule Checker for Sheet MetalComponents using Medial Axis Transforms andGeometric
Design Rule Checker is an essential component of design automation and for making design, process planning and manufacturing concurrent. In this paper, a set of algorithms are presented for detecting design violations in sheet metal components. Violations in sheet metal components occur when holes, slots, or other features are too close to one another. These violations, if undetected during design, increase the design life cycle of the product. Thus it is very essential to detect, if not eliminate these violations at the early stages of design. Typically sheet metal components have a number of features serving various purposes which include ventilation and fastening. As the contour of the parts gets complicated and the number of features on the sheet metal part increases it is diicult to check the rules exhaustively as it may lead to combinatorial explosion. 1 The algorithm presented here, uses Medial axis transformation to decompose a given domain thus preventing a combinatorial explosion, and also provides a means to integrate the rule checker with a design adviser.
Voronoi Diagram for Multiply-Connected Polygonal Domains I: Algorithm
Voronoi diagrams of multiply-connected polygonal domains (polygons with holes) can be of use in computer-aided design. We describe a simple algorithm that computes such Voronoi diagrams in O(N(log
 2 N+H)) time, where N is the number of edges and H is the number of holes.
IGES - the present state and future trends
Although the Initial Graphics Exchange Specification is not without its imperfections and critics, it is widely considered to be the best format currently available for the exchange of CAD data. However, IGES is seen as an interim measure, eventually to be superseded by a new international standard. This article reviews the present state of IGES and considers likely future trends in CAD data exchange.