NSF Young Investigator: Formal Tolerance and Set-Based Methods in Engineering Design and Manufacturing

NSF 青年研究员：工程设计和制造中的形式公差和基于集合的方法

• 批准号: 9258401
• 负责人: Kristin Wood
• 金额: $ 31.25万
• 依托单位: University of Texas at Austin
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-09-01 至 1998-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9258401&HistoricalAwards=false
• 关键词: NSF; Young; Investigator; Formal; Tolerance

This project focuses on a balance between an academic research program, engineering education, and industrial applications. In this program, the general problems of engineering design and design for manufacturing will be addressed. In particular, one part of the research program considers the development of analytical and experimental models for determining the physical surface-structures produced from both material removal processes and solid-freeform fabrication. The basis for these models is fractal-based representations, or more generally the Karhunen-Loeve method, which will provide indices for linking manufacturing process variables to design parameters. While a fractal-based approach is known to be applicable at surface finish scales, surface structures that will be identified in this research are at tolerance scales (e.g., 40-300 microns for journal bearings). Tolerances usually carry the function of the device. For example, in a rotating mechanism, the tolerances associated between a shaft and a bearing assembly may be critical, i.e., if the shaft-bearing assembly is misaligned or out-of-tolerance, catastrophic failure of the system will result due to excessive wear and possible seizure. Providing design methods and measures that link manufacturing process variables to the design parameters, performance parameters, and functional requirements of a design is crucial, especially if manufacturing information is to be combined with functional considerations in the early stages of design. This research will seek to verify the fractal-based models with experimentation, represent the results within a formal set-based theory for design, and apply the method to rotating machinery, structures, and microautomation. Beyond the fundamental theories of fractal tolerances and set-based design representations, computational methods will be developed for linking global geometric information to the design for manufacturing techniques. The general scope for these computational methods will be a feature-based design system, including the formal representation of spatial relationships.

该项目侧重于学术研究计划、工程教育和工业应用之间的平衡。 在该计划中，将解决工程设计和制造设计的一般问题。 特别是，该研究计划的一部分考虑开发分析和实验模型，以确定材料去除过程和固体自由成型制造产生的物理表面结构。 这些模型的基础是基于分形的表示，或更普遍的是 Karhunen-Loeve 方法，它将提供将制造过程变量与设计参数联系起来的索引。 虽然已知基于分形的方法适用于表面光洁度尺度，但本研究中将识别的表面结构处于公差尺度（例如，轴颈轴承为 40-300 微米）。 公差通常承载设备的功能。 例如，在旋转机构中，轴和轴承组件之间的相关公差可能至关重要，即，如果轴-轴承组件未对准或超出公差，则由于过度磨损和可能的卡死，将导致系统的灾难性故障。 提供将制造工艺变量与设计参数、性能参数和设计功能要求联系起来的设计方法和措施至关重要，特别是如果要在设计的早期阶段将制造信息与功能考虑相结合的话。 这项研究将寻求通过实验验证基于分形的模型，在正式的基于集合的设计理论中表示结果，并将该方法应用于旋转机械、结构和微型自动化。 除了分形公差和基于集合的设计表示的基本理论之外，还将开发计算方法，用于将全局几何信息与制造技术的设计联系起来。 这些计算方法的一般范围将是基于特征的设计系统，包括空间关系的形式表示。