Dedicated 3D CAD for garment modelling

While considerable progress has been made in fabric modelling techniques, which could be used in garment computer aided design (CAD) systems, less attention has been paid to the way in which garments might be specified in a CAD system. The final shape taken by a garment is often achieved through the incorporation of darts, seams, edges, stiffening pads and local stretch of the fabric. In order to gain credibility, CAD systems should have to functionally handle the level of complexity normally found in garment assemblies combined with a simple interface to specify the constructional detail. Different conceptual approaches are possible. Given an accurate drape algorithm, garment block patterns in a chosen fabric could simply be anchored or attached around the mannequin in order to achieve a visualisation of a garment. If changes were necessary, the user would alter the 2D patterns and re-run the visualisation. An alternative and possibly more productive approach would be to specify in 3D, with advanced drawing tools, the 3D shape required. Processing of the 3D garment piece using expert rules would indicate the 2D shape and constructional detail required to achieve the final form. This paper describes a CAD system that is under development and which aims to facilitate both the approaches.