3D Shaping with Tertiary Tool Motion

通过三次工具运动进行 3D 成形

• 批准号: 0600175
• 负责人: Kornel Ehmann
• 金额: $ 39.83万
• 依托单位: Northwestern University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-03-01 至 2011-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0600175&HistoricalAwards=false
• 关键词: 3D; Shaping; Tertiary; Tool; Motion

The two objectives of this research project are: (1) to conceive an ultra-precision micro/meso-scale machining method for a subclass of three-dimensional free-form surfaces with the concurrent control of their surface topography, and (2) to establish the analytical basis for the process kinematics and cutting mechanics. In the proposed method, primary and secondary motions of a cutting tool are supplemented by a tertiary motion component consisting of controlled small-amplitude closed trajectory motions at ultrasonic frequencies. For the generation of the tertiary motion two alternatives will be explored. The first is based on a piezo-driven two-dimensional flexure design, while the second on a tunable ultrasonic elliptical oscillator. Supporting theoretical work will focus on the analytical formulation of the machine's command sequences for the generation of desired topological features on the surface. Initially, this will be accomplished through geometric and kinematic considerations and later extended to include cutting mechanics related effects such as elastic and plastic deformation, minimum chip thickness influences and others. A prototype machine will be designed, manufactured and tested under different cutting scenarios implemented in conventional and ductile cutting regimes. If successful, the newly conceived micro-cutting process will offer capabilities that cannot be achieved by current competing operations. Its advantages are: (1) very high cutting velocities, (2) ability to impart intricate surface patterns by modulating and phasing the motion components, and (3) creation of sculptured surfaces with controlled topography. The method also offers an alternative to micro-endmilling and eliminates the need for ultra-high-speed low runout spindles. From the scientific standpoint, the combination of theoretical, computational, and experimental methodologies will provide the fundamental understanding of the developed machine's capabilities and of the new processes it executes. Since micro-manufacturing is a fairly new research area, the knowledge base and machine prototype created through this research will provide the necessary educational and physical infrastructure for continued exploration of micro/meso-scale cutting processes.

本课题的主要研究目标是：（1）提出一种三维自由曲面类的超精密加工方法，并实现其表面形貌的同时控制;（2）建立加工运动学和切削力学的解析基础。在所提出的方法中，主要和次要的运动的切削刀具补充由第三运动组成的控制小振幅的闭合轨迹运动在超声频率。对于第三运动的生成，将探索两种替代方案。第一个是基于压电驱动的二维弯曲设计，而第二个可调超声椭圆振荡器。 支持的理论工作将集中在机器的命令序列的分析制定所需的表面上的拓扑特征的生成。最初，这将通过几何和运动学的考虑来实现，后来扩展到包括切削力学相关的影响，如弹性和塑性变形，最小切屑厚度的影响和其他。一个原型机器将设计，制造和测试下，在传统和韧性切割制度实施不同的切割方案。如果成功，新设想的微切割工艺将提供目前竞争性业务无法实现的能力。其优点是：（1）非常高的切割速度，（2）通过调节和定相运动分量赋予复杂表面图案的能力，以及（3）产生具有受控形貌的雕刻表面。 该方法还提供了一种替代微端铣，并消除了对超高速低跳动主轴的需要。从科学的角度来看，理论，计算和实验方法的结合将提供对所开发机器的能力及其执行的新过程的基本理解。由于微型制造是一个相当新的研究领域，通过这项研究创建的知识库和机器原型将为继续探索微/中尺度切割过程提供必要的教育和物理基础设施。