Abstract
A solid model representing product requires fillet or blend process, which rounds a specified edge or vertex, in order to make a production model for manufacturing purpose such as mould die model. Current major solid model CAD systems are based on boundary-representation (B-rep) and they represent faces using trimmed free-form surfaces. However, their models have problems in blend process to become unstable at edges of narrow faces or at both ends of such faces. We propose that a new boundary-representation structures and new blend algorithms which enable blend process to become robust. In this report, we propose a procedural blend-representation that surfaces are not represented explicitly.
