快速可展窄带曲面设计

Efficient developable strip surface design

针对在服装、制鞋、钣金等行业的产品外形设计中,经常需要插值两条特征空间曲线,构建光顺可展窄带来过渡连接相邻的两可展曲面(可无伸缩地展开成平面)的问题,提出了一种新算法支持可展窄带的优化实时设计。其中:一条线为样式线,承载了外形褶皱的设计要求,通常固定不变;另外一条为设计线,允许其在指定的范围内进行变动(该范围通过两曲面嵌入线进行限定),并且保证设计线始终处于一个被连接的可展曲面上。该问题最终可转换为离散组合优化与非线性约束优化相混合的优化问题,可迭代进行快速求解。最后与主流计算机辅助设计软件Cimatron以及文献[1]中的方法进行了对比测试。测试结果表明该算法在造型速度上以及可展窄带的可展度方面均具有明显优势。所提算法对于相关行业的可展窄带外型设计具有实际工程应用价值。

In some industries such as garments,shoes and metal building,etc,one developable strip surface is often required to interpolate two specified set of skeleton curves such that two neighboring developable patches（which can be flattened onto planed without any distortion,tear or stretch） can be smoothly joined together.To solve this problem,this paper proposed a novel algorithm to support the design of developable strip at an instant rate： one of the bounding curves,i.e.,pattern curve,was fixed to carry some appeal requirement such as wrinkles;the other one,called design curve,would be perturbed within a controllable tolerance（which was defined by two embedded curves） and guaranteed it be on one of neighboring developable patches all the time.The problem was formulated as a combination of a discrete combinatorial optimization problem and a constrained nonlinear optimization problem,and could be solved in an efficient iterative manner.Cimatron and the method in[1] were set up as benchmark.Experiments show that the proposed algorithm has obvious advantages in both speed and developability of the final strip surface.The proposed is of practical engineering senses in designing strip surfaces in related engineering applications.