关键词: 草绘线, 三维曲线, 自由曲面, 压力变形, 实体建模

Abstract: To build a 3D shape rapidly for production concept designing, a kind of sketch based solid modeling system oriented to industrial products shape design was put forward. The 3D curves were constructed directly by using the method of sketch curve principal direction estimation. Based on minimum energy of active contour models, the 3D curves were modified. The 3D curve whose spatial deviation minimized from original target curve was taken as 2D curve projection result, thus 3D freeform surfaces were designed through using methods such as edge exchanging and triangle-division. Finally, a pressure-based deformation method was proposed to modify and refine the surface. With this system, users could rapidly and intuitively design 3D modeling in interactive mode. The efficientiveness of algorithm and the feasibility of engineering were verified by a variety of different modeling test on self-developed software platform.

Key words: sketch, 3D curves, freeform surface, pressure deformation, solid modeling