Research & Application Of Parametric Technology In Apparel CAD Based On Human Iandmarks

It is an inevitable trend for GCAD system to convert to 3D from 2D because of the 3D computer technique's maturity and the necessity of customized garment. Also it is important to import parametric design to GCAD, since it can significantly improve the automation degree and efficiency of apparel enterprises. Based on the analysis of GCAD status quo and the problems remained, a new GCAD parametric method according to human body's landmarks is put forward in this thesis.The essential of the new GCAD parametric method is to generate a new garment template based on the detection of human body's landmarks and to support parametric design. In chapter 2, a definition of human body's landmarks and its detection algorithm is presented. To improve the efficiency of the algorithm, body models are simplified firstly. A detailed definition of landmark on models is given based on anthropometries. Then a searching method with controllable searching step is proposed according to the distribution law of landmarks. Some demos are introduced finally.The garment is tightly affiliated with the character of human body. In chapter 3, a concept of garment geometric elements is put forward. They are created from human body's landmarks, of which the spline curve is the basic element. Utilizing the piecewise technique, the 3D garment surface is generated on the basis element and blended, fined. It extends parametric methods to high-level entities including the spline curve and mesh.Parametric CAD is one of trends of computer-aided design, so does GCAD. In chapter 4, a parametric method for 3D garment design is presented. Based on the features of garment, three relations are firstly introduced as the constraints of garment geometric elements, then a constraint graph is established, which describes the relations of garment geometric elements. Parametric design of 3D garment is realized by resolving the constraint relations and a appliance example is given lastly.Based on the research work above all, a "DressingSim R&D" system is introduced in chapter 5, including its buildup, structure and main functions, also with some examples,which testifies the feasibility, validity and advancement of the technology presented in thethesis. Finally, the development of 3D GCAD is summarized and the future work is putforward.