Abstract:

Existing part's coding method based on the assembly structural model was to search all structural codes and compare all codes in part retrieval. It reduced the retrieval efficiency. To solve this problem, a method to find critical structures of the parts based on formal concept analysis was proposed. By mapping relationships among the part functional surfaces and the positions to the binary formal context, a concept lattice of 3D parts structural model was built. Weights were designed by the information entropy, the important attributes and the intents were found, then the formal concepts were sorted. The users can set thresholds as well as the deviation with the central weights to determine critical structure of the parts. It  lays the basis for the efficient parts query using structure coding.

Key words: part structure coding, concept lattice, information entropy, critical structure

摘要：

已有的基于装配结构模型的零件结构编码方法,是对所有结构码进行搜索对比的,因而检索效率不高。为解决这一问题,提出了一种基于形式概念分析的关键结构确定方法。通过将零件功能表面与位置关系映射为具有二元关系的形式背景，构建了三维零件结构模型的概念格。引入信息熵，用权值发现重要属性以及概念内涵，从而对不同重要程度的形式概念进行了排序。据此可根据设定的阈值并考虑与中心权值的偏差确定零件的关键结构，这为利用结构编码进行高效零件查询奠定了基础。

关键词: 零件结构编码, 概念格, 信息熵, 关键结构