【作者】 高宇；

【导师】 李基拓；

【作者基本信息】 浙江大学 ， 机械设计及理论， 2016， 硕士

【摘要】 将2D服装裁片在3D人体上通过物理模拟缝合成3D服装,是目前主流的3D服装建模方法,其基本流程如下：对2D服装裁片网格化,将其定位到3D人体周围,设置裁片之间的缝合信息由物理模拟实现裁片之间的拼接,并悬垂到人体模型上,得到真实感的三维服装模型。本文对该设计模式中存在的几个重要问题进行研究：(1)为使裁片缝合后呈现多种工艺细节,如松紧带的收紧效果,裁片网格模型需满足服装缝制工艺的相应要求。现有3D服装缝合系统虽然可实现裁片网格化处理,但难以满足服装缝合模拟时的复杂工艺需要。本文将服装缝制工艺需求转化为裁片网格化处理时的各类几何约束,使裁片的网格化结果能用于模拟多种服装缝制效果。(2)要将裁片在人体模型上缝合成衣,首先需要将裁片放置在人体周围合适位置。现有系统大都在三维空间域上对裁片位置做交互调整,交互难度较高。本文提出了基于2D-3D操作域映射的裁片3D定位方法,通过在2D操作域内进行简单交互完成裁片3D定位,操作更为简易。针对裁片与人体以及与其它裁片之间存在干涉的情况,本文设计了3D特征点引导包络及空间坐标球任意拖拽两类交互方式对裁片初始位置进行微调,以消除干涉。(3)对于复杂服装的缝合模拟,需要设定的缝合信息往往多达几十组甚至上百组。在已有3D服装缝合系统中,大都通过交互式选择对缝边逐一设定所有缝合信息,在很大程度上制约了服装建模的效率。本文提出了基于服装多层级特征的自底向上的裁片间缝合信息智能设定方法,自动求解裁片间等长度缝合问题,提高了缝合过程的自动化程度。基于上述研究,本文开发了3D服装缝合系统,根据给定的2D服装裁片及3D人体,可实现：1)满足服装缝合模拟需求的2D服装裁片三角剖分；2)2-3D联动的裁片3D定位与形状编辑；3)智能的裁片间缝合信息设定；4)基于物理的裁片缝合及悬垂。更多还原

【Abstract】 Currently,3D garments are mainly created by stitching 2D garment patterns on 3D human models. Its general process is as follows:Firstly,2D patterns are discretized into rectangular or triangular meshes; secondly 2D patterns are interactively positioned near the 3D human bodies; thirdly, the stitching pairs are set among the 2D patterns; finally, patterns are stitched together on the 3D human models to form realistic 3D garment models based on physics. This thesis studied several important problems in the 3D garment modeling and proposed corresponding solutions, which are detailed as follows.(1) In order to simulation different kinds of stitching, such as the tightening effect of the elastic belt, the 2D patterns should be triangulated properly, which is difficult to most existing 3D garment modeling systems. In this thesis, the stitching requirements are converted into various geometric constraints in 2D pattern triangulation. Using such triangulated 2D patterns, a lot of stitching effects can be simulated based on physics.(2) To stitch the patterns into a garment, the patterns should be positioned properly around the human body. Usually, it is realized by directly dragging 2D patterns in 3D space, which however is not easy to operate. In this thesis, a 3D-2D operation mapping has been set, thus the 3D positioning of 2D patterns can be achieved by 2D operations.To tackle with the interference between patterns and the human body or interference among patterns, two interactive methods have been proposed. One is the enveloping method based on 3D feature points; the other is dragging method based on 3D coordinate ball. With these two methods, the positions of patterns can be fine tuned, which is useful to remove the interference.(3) In modeling complicated garments, the number of stitching pairs is usually more than tens or even more. In most existing systems, stitching pairs are set up manually, which greatly restricts the garment modeling efficiency. In this thesis, a bottom-up method for setting stitching information based on the multi-layer feature is proposed, which can automatically solve the problem of equal-length suture between the patterns. Thus automation degree of garment stitching process is improved.Based on the above research, a 3D garment stitching system was developed. The system has following functions:1) Triangulating 2D patterns with constraints to meet the requirements of garment sewing; 2) Positioning or editing patterns in 3D space conveniently by 2D operations; 3) Setting stitching information intelligently; 4) Stitching and draping simulation based on Physics.更多还原