Abstract: To realize the effective reuse of the existing CNC process design results, a model of CNC process recommendation system was proposed based on local feature matching. Combined with the geometric semantic informations, such as the size and so on, the 3D polar radius moments of the local features were used, to establish the machining geometric features. And the CNC process informations of the typical local features were efficiently organized and expressed, to construct the CNC process case database. In addition, a similarity measure method was designed based on the comprehensive weighing of the machining geometric features, to achieve the local feature retrieval and the accurate matching of the machining features. The CNC process instance reuse method was defined according to the matching degree and the users' process demands, to generate applicable CNC process recommendations.

Key words: CNC machining, process reuse, similarity measure, feature retrieval, recommendation system

摘要： 为了实现对已有数控工艺设计成果的有效重用，提出了一种基于局部特征匹配的数控工艺推荐系统模型，该模型利用局部特征级的三维极半径矩结合几何尺寸等其他几何语义信息建立加工几何特征，并对典型局部特征对应的数控工艺信息进行有效组织与表达，构建数控工艺案例库。设计了一种基于综合加权的加工几何特征的相似性度量方法，以此实现局部特征的检索与加工特征的准确匹配，并根据匹配程度定义数控工艺实例复用方法，结合用户加工需求，最终产生合适的数控工艺推荐方案。

关键词: 数控加工, 工艺复用, 相似性度量, 特征检索, 推荐系统