SBIR Phase I: Creating Functionally Decomposed Surface Models from Measured Data

这个小型企业创新研究（SBIR）第一阶段项目处理的问题是从测量数据重建复杂的自由形状。主要的兴趣是创建良好的结构，高质量的CAD模型。有几种技术可以达到这个目标。不幸的是，自动表面系统只提供粗略的近似，不能捕捉原始的设计意图，而手动分割方法不是很稳定，需要繁琐的工作。使用功能分解范例，对象被构建为由较小的、相关的特征表面（如圆角或扫面）连接的大型、独立的主表面的集合。该项目旨在详细阐述半自动方法，以建立对象的拓扑结构并计算单个点区域的最佳表面表示。重点介绍了用于重新定位分割曲线网络的不同整流方法和用于确保与现有曲面几何平滑连接的不同约束曲面拟合算法。本研究从几何建模的理论基础开始，然后通过原型实现来证明算法的可行性和有效性。这项技术将大大缩短相关工业设计和制造过程的交货时间，并生产出更多美观的产品。主要应用将是产品设计，包括汽车、航空航天、消费产品和医疗设备。改进后的产品将通过提供一种引入按需设计和按需工程服务的方式，帮助美国制造业在世界市场上更具竞争力。它还将帮助美国公司增加以客户为中心的生产，并缩短产品迭代之间的时间。

This Small Business Innovation Research (SBIR) Phase I project deals with the problems of reconstructing complex freeform shapes from measured data. Of primary interest is the creation of well-structured, high- quality CAD models. Several techniques exist to reach this goal. Unfortunately, automatic surfacing systems provide only rough approximations and do not capture the original design intent, while manual segmentation methods are not very stable and require tedious work. Using the functional decomposition paradigm, objects are built up as a collection of large, independent primary surfaces being connected by smaller, dependent feature surfaces, such as fillets or swept surfaces. This project aims to elaborate semi-automatic methods to build up the topology of the object and compute optimal surface representations for the individual point regions. Emphasis is put on different fairing methods to relocate the segmenting curve network and different constrained surface fitting algorithms to assure smooth connections to existing surface geometry. The proposed research starts with theoretical ground work in geometric modeling, followed by a prototype implementation to prove the feasibility and efficiency of the algorithms.This technology should significantly shorten lead-time in related industrial design and manufacturing processes and produce more aesthetic objects. The main applications will be product design, including automotive, aerospace, consumer products, and medical devices. The improved product will help US manufacturing industry to be more competitive in the world market by providing a way to introduce design on demand and engineering on demand services. It will also help US companies increase customer-focused production and reduce the time between product iterations.