融合规则的典型工艺表示与工艺决策方法研究

为了简便有效地表示工艺知识,提高工艺决策的自动化程度和灵活性,文章提出了一种融合规则的典型工艺表示与工艺决策方法.该方法将与典型工艺相关的信息分为不变信息和可变信息,不变信息基于统一的典型工艺信息模型进行表示,而可变信息以产生式规则形式表示,并嵌入到典型工艺中.由于每个典型工艺都有与之密切相关的一套独立规则,规则的针对性很强,所以规则的总结、形成容易,便于实现工艺决策的自动化.文中以飞机结构件的数控加工工艺为例,对融合规则的典型工艺的表示、基于制造特征的产生式规则分类和工艺决策算法进行了详细讨论.该方法已在某飞机制造企业的CAPP系统中进行了实际应用,实现了工艺决策的自动化.应用表明这种工艺知识表示及其决策方法简单有效,规则维护扩充方便.

Exploring Rule-Fused Technology for Typical Process Representation and Automatic Process Decision

Aim. Chinese researchers previously explored the above mentioned topic in Refs. 2, 4 and 5 but, in our opinion, their results are not useful in so far as practical applications are concerned. Our exploration, we believe, has made some progress in this respect; furthermore, the results of our exploration have been utilized with some success in the CAPP (computer aided process planning) system of a Chinese aircraft manufacturing enterprise. Sections 1, 2 and 3 of the full paper explore the rule fused technology for typical processes representation. Their core consists of: (1)a typical process is divided into variable information and invariable information; the invariable information is represented by the uniform model of the typical process, while the variable information is represented in the form of production rules which are embedded into the typical process; (2) because each typical process has a set of independent rules and the rules are closely related to the typical process, it is easy to define the rules and to automatically realize process decision making based on the rules. Section 4 explores the rule fused technology for automatic process decision and, taking as example the typical processes of groups of aircraft structure parts, discusses the automatic process decisions in some detail.