RE-SOFT系统架构及关键技术

介绍了专业反求工程软件RE-SOFT的体系结构,提出了两条解决反求工程CAD建模的路线和策略：一是再现产品从二维到三维的设计过程,即基于截面特征的反求建模路线要求,首先解决点云切片、二维特征元提取、约束施加以及截面曲线全局约束优化,然后通过拉伸、旋转等手段重构曲面模型;二是解决功能特征曲面“分治”再现和优化设计的快捷方法,即基于曲面特征的反求建模强调从点云中直接提取圆锥曲面、过渡曲面、规则扫略面等特征元素,并通过三维特征间的拓扑约束和全局优化生成曲面模型.通过以上两条基于特征的反求建模理论研究和实现,可以看出新一代反求工程软件更加重视建模过程和结果表达的完整参数化,寻求更高水准的支持产品变形设计和创新设计.建模实例表明,应用RE-SOFT系统可以快速获得完整特征表达的理想CAD模型.

Architecture and key techniques of feature-based reverse modeler-RE-SOFT

System architecture of RE-SOFT, a feature-based reverse modeler, was proposed. And two integrated solutions to reconstruct solid model from point cloud were presented. One strategy recovered the design flowchart from 2D to 3D, in which point cloud slicing, curve feature detection and constrained fitting techniques were discussed in details. Another strategy extracted geometric features from point cloud such as analytic surface, blending surface, regular swept surface, etc. Based on these feature elements,the B-rep model can be reconstructed through topological operations and constrained fitting. This strategy was a fast solution for feature recovery and optimal design of functional surface. Compared with the existing reverse modeling strategies, the proposed strategies can accurately capture the original design intent,conveniently construct model from point cloud and support the creative design of product in high level. Application analysis illustrated that, with RE-SOFT, ideal feature-based model representation can be obtained efficiently and accurately.