NURBS tool-path generation and accurate machined-part modeling in virtual 5-Axis milling for high-performance cutting of sculptured parts

随着计算机辅助设计（CAD）技术的发展，具有雕刻零件的机械产品已广泛应用于航空、汽车、模具等行业。包括五轴数控机床在内的可重构制造系统，能够以更高的质量、更低的成本和更短的交货期生产各种产品；因此，在经济全球化的过程中，它们对这些行业的公司至关重要。作为数控加工系统的核心技术，五轴工件的高性能加工是一个巨大的挑战，尽管它在工业上是非常需要的。一个有效的解决方案是虚拟五轴加工系统，它可以通过考虑机床动力学和CNC程序来模拟真实的切削过程，生成高保真的加工零件模型，并检查数字零件的表面精度小于0.01 mm。为了克服现有虚拟系统的缺点，本新提出的研究旨在开发和推进一些关键技术：(i)五轴雕刻零件加工的刀具尺寸优化，（ii） NURBS刀具路径规划，以实现光滑，精确的表面和良好的机床动力学，以及（iii）具有高保真度的虚拟加工零件建模。

With advances in the CAD technology, mechanical products with sculptured parts have been widely adopted in the aeronautical, automotive, and die and mold industries. Reconfigurable manufacturing systems, including 5-axis CNC machine tools, are capable of making diverse products with better quality, less costs, and shorter lead time; thus, they are essential to the companies in these industries during economic globalization. Being a kernel technology in the systems, high-performance 5-axis machining of the sculptured parts is a great challenge, even though it is badly needed in industry. An effective solution to the challenge is virtual 5-axis machining systems that can simulate real cutting processes by taking machine tool dynamics and CNC programs into account, generate machined part models with high fidelity, and inspect the digital parts for surface accuracy less than 0.01 mm. To overcome the drawbacks of the existing virtual systems, this newly proposed research aims to develop and advance some key techniques: (i) cutter size optimization for 5-axis sculptured part machining, (ii) NURBS tool path planning for smooth, accurate surfaces and good machine tool kinetics, and (iii) virtually-machined part modeling with high fedelity.