三维服装CAD中几何约束表达及其求解技术研究

Research on Geometric Constraints Description and Solving Technique in Apparel CAD

从人体及服装的特点出发,提出三维服装几何元素的概念采用样条曲线作为基本几何元素,归纳出服装的三种约束关系,即共点、对称和自对称关系;成为约束关系形成的基础 以三种约束关系为基础,建立了面向服装的几何约束图,有效地表达了三维服装几何元素及其相互关系;实现了一种基于约束图的约束求解方法,从而完成了构造服装及对服装的交互参数化修改,文中给出了应用实例,并将参数化方法向高层次图素如样条曲线、曲面作了推广,成功地应用于以样条曲线为几何元素的参数化服装CAD系统中。

This paper presents a parametric method for 3D garment design. Based on the features of the human body and garment, we present a concept of garment geometric elements, with the spline curve as its basic element. Three relations, same-point, symmetry and self-symmetry are firstly introduced as the constraints of garment geometric elements, then a constraint graph is established, to describes the relations of garment geometric elements. Finally, parametric design of 3D garment is realized by resolving the constraint relations. This study extends parametric methods to high-level entities including the spline curve and mesh. The method has been successfully applied in a 3D garment design system.