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。我的研究将有助于对虚拟五轴加工系统的基本理解和技术进步，以实现高性能的雕刻零件切割。我的发现也将有助于了解CNC加工，CAD/CAM和先进制造的一般知识，所有这些都具有广泛的工业应用。此外，这项研究是对现有nserc资助的CNC加工项目的补充，其成果将通过我与加拿大普惠公司，庞巴迪公司和一些当地模具公司的合作直接应用于我们的工业生产。更重要的是，这项研究计划将为加拿大制造业提供高素质人才的培训。

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.  My research will contribute to the basic understanding and technological advancement of virtual 5-axis machining systems for high-performance cutting of sculptured parts.  My findings will also contribute to the general knowledge on CNC machining, CAD/CAM, and advanced manufacturing, all of which have broad industrial applications.  Also, this research is complementary to the existing NSERC-sponsored projects on CNC machining, and its results will be directly applied to our industrial production through my collaboration with Pratt & Whitney Canada, Bombardier, and some local die and mold companies. More importantly, this research program will provide training to high qualified personnel for the Canadian manufacturing industry.