Characterization of Functional Requirements and Dimensional Tolerances for Design and Manufacturing

该项目的长期目标是开发支持设计和制造中的并行工程的功能框架。其目的是缩短设计周期，提高生产率，更重要的是，提出最佳或接近最佳的设计和生产计划。为了实现这一目标，确定了两个具体目标。第一个是描述用于创建产品功能结构的各种机械功能。功能结构将有助于将功能需求整合到产品周期的各种活动中，从而成为设计、工艺规划、制造、组装和检验之间的纽带。第二个目标是根据所需功能的特点制定一个功能公差框架。使用公差表示方案，可以将当前的公差表示方法扩展和应用于功能复杂和/或几何复杂的产品。这项研究将为机械设计中的功能需求的表征和表示提供一种系统的方法。它将为将设计意图集成到产品周期中提供基础，从而使确定最佳产品设计和工艺规划的更高级别的决策和复杂的推理成为可能。

The long-term goal of this project is to develop the functional framework that supports concurrent engineering in design and manufacturing. The purpose is to shorten the design cycle time, to increase productivity and, more importantly, to come up with optimum or near-optimum design and production plans. In order to accomplish this goal, two specific objectives are identified. The first one is to characterize the various mechanical functions for creating the functional structure of a product. The functional structure will facilitate the integration of the functional requirements into various activities of the product cycle so as to serve as the links among design, process planning, manufacturing, assembly, and inspection. The second objective is to develop a functional tolerancing framework based on the characteristics of the required functions. Using the tolerancing scheme, the current practice of tolerance representation can be extended and applied to the products that are sophisticated in function and/or complicated in geometry. The research will result in a systematic approach for the characterization and representation of the functional requirements in mechanical design. It will provide a basis for integrating design intent into the product cycle so that higher level of decision making and complex reasoning for the determination of optimum product design and process planning become possible.