回转体零件智能化CAPP系统的设计与实现

【作者】 赵友亮；

【导师】 杨青； 何东健；

【作者基本信息】 西北农林科技大学 ， 机械设计与理论， 2002， 硕士

【摘要】 工艺设计是连接产品设计与制造的桥梁，计算机辅助工艺设计(CAPP)作为工艺设计的计算机实现方式，是CAD／CAM集成乃至实现CIMS的关键技术。但与CAD、CAM相比较，CAPP的应用、研究与发展相对滞后。一方面是因为工艺设计方法迄今缺乏良好的理论和坚实的科学基础，另一方面是因为CAPP系统的运行对加工环境的依赖性强，制约着自身的应用与发展。不论是从其自身发展的角度考虑，还是从与其它技术实现集成的角度来考虑，CAPP系统必须具备良好的环境适应能力。 本文以在智能化基础上实现回转体零件CAPP系统柔性化为目标，对其实现过程中的技术方法进行了研究，开发了一个智能化的回转体零件CAPP原型系统。主要内容包括总体结构设计、零件信息的描述与输入、工艺数据库和工艺决策推理设计等几部分。 借签专家系统中推理与知识分离实现问题求解的技术方法与思想，完成了系统总体设计和功能模块划分。 在对回转体零件构成特性分析的基础上，采用形面描述法的思想实现了零件形面要素的定义、编码及其描述参数的确定。构造了零件信息模型，并以此模型为基础完成了零件信息的输入与存储设计。 提出基于关系数据库的工艺决策模型，实现了工艺知识数据与工艺决策程序的相对分离。以此模型下工艺决策推理的实现为目标，用实体一联系法对工艺知识数据进行了分析、整理和结构设计，用关系数据模型实现了工艺知识的表达与存贮。 根据系统总体结构和设计目标，按正向分级推理的方法实现了工艺决策推理各功能模块的设计。系统中不仅工艺知识与工艺决策程序分离，能适应不同加工环境下工艺知识的更新与维护，而且其零件信息输入模块、工艺数据库可完全用于其它同对象的系统中，柔性化程度高。 系统使用Visual Basic6.0开发，运行于中文Windows环境下。实例零件运行表明，系统结构合理、人机界面友好、决策过程透明、易于扩充维护。研究结果对CAPP技术的理论研究和应用发展有一定的现实意义。更多还原

【Abstract】 Process planning is the bridge which link product design with manufacture. CAPP as Computer realizing way for process planning, is the critical technology to realize CIMS and CAD/CAM integration. However its application study and development relatively lag CAD and CAM. The reason lies in two facets: the one is that process planning is not supported by better theory and firm scientific foundation, the other is that CAPP system’s depending on works environment limits itself application and development. Considered from its own development as well as integration with other skills, CAPP must possess the capacity of fitting various situation. To adapt to the trend, referring to the idea of experts system that knowledge is separated from deduce procedure, a generative CAPP prototypes system for turning parts was studied and designed, which included the creation of system structure. Description and input of parts process database, and process deduce and illation etc.On a basis of analyzing turning parts’ composing characteristic, adopting the form describes, the form factor’s definition & coding for parts was realized, the information model of parts was formed, and the inputting design of parts information was accomplished. Foundation of analyzing the inner relation between processing design and knowledge needed, using relation list, process knowledge data’s expression & saving was realized. Still in term of process knowledge structure and designing goal, taking advantage effacing illation, classification, the procedure design of process decision was achieved. In system not only the process knowledge & decision procedure apart can suit for updating & protecting of process knowledge in different environment, but also the inputting module of parts information & process database can be used in other similar system.The system uses Visual Basic 6.0, and runs in Chinese Windows, which makes it has a reasonable structure & perfect interface, also makes it easy to amplify & protect. The running consequence can ultimately realize our designing target.更多还原