Variable Weight Non-Uniform Rational B-Splines, Offset Surfaces, and Gouging-Free Computer Numerical Control Tool Path Generation

可变权重非均匀有理 B 样条、偏置曲面和免气刨计算机数控刀具路径生成

• 批准号: 9713913
• 负责人: Kwun-Lon Ting
• 金额: $ 15.43万
• 依托单位: Tennessee Technological University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-10-01 至 2001-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9713913&HistoricalAwards=false
• 关键词: Variable; Weight; Non; Uniform; Rational

This grant provides funding for the development of variable weight non-uniform rational B-splines (VW NURBS), a method for offset surface generation, and a technique for gouging-free tool path identification in computer numerically controlled (CNC) machining. The properties of VW NURBS will be explored. The results from VW NURBS will be applied to approximate offset curves and surfaces, in which the error can be adjusted by constructing weight functions of VW NURBS and by using a subdivision algorithm. The gouging condition of a CNC machining tool path will be identified by using the offset surface in user interface. The proposed method will determine the optimal cutter radius and its inclination angle to avoid any local interference in manufacturing free-form surfaces with a ball-end mill or a flat-end mill. If successful, this research will lead to a fundamental advancement in CAD/CAM development. VW NURBS is a systematic extension of NURBS, the most promising model used in the current commercial CAD/CAM software. It offers a more general model than NURBS and can enhance the flexibility, capability, and efficiency of CAD/CAM systems. In addition to CNC machining, the method of offset curve and surface generation can also be applied to tolerance analysis, mold and die making, rapid prototyping, robot path planning, and finite element mesh generation. The proposed gouging identification method will allow one to optimize the cutter size and orientation easily, and hence, enhance the productivity and quality of CNC machining.

该补助金为开发可变权重非均匀有理B样条（VW NURBS）提供资金，这是一种偏移曲面生成方法，以及一种用于计算机数控（CNC）加工中无过切刀具路径识别的技术。 将探讨VW NURBS的特性。 将VW NURBS的结果应用于等距曲线曲面的逼近，通过构造VW NURBS的权函数和细分算法来调整误差。 通过用户界面中的偏置曲面来识别CNC加工刀具路径的过切情况。 所提出的方法将确定最佳的刀具半径和倾角，以避免任何局部干涉加工自由曲面的球头立铣刀或平头立铣刀。 如果成功，这项研究将导致CAD/CAM发展的根本性进步。 VW NURBS是NURBS的系统扩展，NURBS是当前商业CAD/CAM软件中最有前途的模型。 它提供了比NURBS更通用的模型，可以提高CAD/CAM系统的灵活性、能力和效率。 除了CNC加工外，等距曲线曲面生成方法还可应用于公差分析、模具制造、快速成型、机器人路径规划、有限元网格生成等领域。 提出的过切识别方法将允许一个优化的刀具尺寸和方向容易，因此，提高生产率和CNC加工质量。