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

随着CAD技术的进步，具有雕塑零件的机械产品在航空、汽车和模具行业得到了广泛的应用。包括五轴数控机床在内的可重构制造系统能够以更好的质量、更低的成本和更短的交货期制造出多样化的产品；因此，在经济全球化的今天，它们对于这些行业的公司来说是必不可少的。作为系统的核心技术，高性能的五轴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，它可以考虑机床动力学和数控程序来模拟真实的切割过程，生成高保真的加工零件模型，并检测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，提出了一种基于虚拟五轴加工系统的虚拟五轴加工系统这项新提出的研究旨在开发和推进一些关键技术：(I)五轴复杂零件加工的刀具尺寸优化；(Ii)光滑、精确的曲面和良好的机床动力学的NURBS刀具路径规划；(Iii)高逼真度的虚拟加工零件建模。我的研究将有助于对用于高性能加工的虚拟五轴加工系统的基本认识和技术进步。我的研究成果也将有助于了解数控加工、CAD/CAM和先进制造的一般知识，这些都具有广泛的工业应用。这项研究是对NSERC赞助的现有数控加工项目的补充，其结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，该研究项目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.