装配序列规划的知识与编码研究

发布时间：2018-07-07 17:06

本文选题：装配序列规划 + 有根装配二叉树　；参考：《华中科技大学》2015年硕士论文

【摘要】：计算机辅助装配规划是研究装配规划的重要热点,其研究方法主要分为几何推理方法和基于知识的推理两大类。基于知识的推理方法引入了人的经验知识和启发式的装配规则,能很大程度上地减少几何推理的组合爆炸问题,避免装配序列规划的盲目性。在装配规划中,如何利用已有的装配经验和装配知识是一个重要问题。通过分析和模仿计算机辅助工艺规划的成熟方法,将成组技术引入到装配序列规划中来,将零件编码技术拓展到装配体编码,通过装配编码搜索,零件匹配和序列修正,实现装配序列的重用。本文提出了装配树和有根装配二叉树的概念,介绍了装配树的计算机表示与存储方法,设计了装配知识库的模型,包括装配序列知识和装配规则知识,用于存储基础的连接传动知识和启发式的装配规则,介绍了如何实现装配知识的计算机表示方法;采用层次化的思想和方法,将常见的机械装配体分为基础级、组件级、产品级三类。采用类似零件编码系统的方法对装配体进行编码,定义了装配体通用编码各码位的含义和编码方法,从名称类别,形状尺寸,装配复杂度三方面描述装配体,并对常见的轴系类装配和箱体类装配进一步细分,进行特殊化编码;以装配体名称和编码为主要关键特征,通过检索装配序列知识库,采用一种逐级放宽匹配条件的方法来检索相似装配体,通过对应的相同或相似的零件匹配与映射后,完成新的装配序列规划,并更新数据库。在数据库中,为了定义两棵有根装配二叉树的距离,引入了Robinson-Foulds距离和其具体形式的推演与应用,以及有根装配二叉树的矩阵编码方法,并以一个经典的机械产品为例说明本文提出的装配序列规划流程;基于CATIA平台及其二次开发技术,介绍了本研究系统的实现原理与流程,开发了部分功能模块KASP。
[Abstract]:Computer-aided assembly planning is an important research hotspot in assembly planning. Its research methods are divided into geometric reasoning method and knowledge-based reasoning method. Knowledge-based reasoning method introduces human experiential knowledge and heuristic assembly rules, which can greatly reduce the combinatorial explosion problem of geometric reasoning and avoid the blindness of assembly sequence planning. In assembly planning, how to make use of the existing assembly experience and assembly knowledge is an important problem. By analyzing and imitating the mature method of computer aided process planning, the group technology is introduced into assembly sequence planning, and the part coding technology is extended to assembly body coding, through assembly coding search, part matching and sequence modification. The reuse of assembly sequence is realized. This paper presents the concepts of assembly tree and root assembly binary tree, introduces the computer representation and storage method of assembly tree, designs the model of assembly knowledge base, including assembly sequence knowledge and assembly rule knowledge. This paper introduces how to realize the computer representation method of assembly knowledge, which is used to store the basic knowledge of connection transmission and heuristic assembly rules, and adopts the idea and method of hierarchy to divide the common mechanical assembly parts into basic level, component level, There are three types of products. The method of similar part coding system is used to encode the assembly, and the meaning and coding method of the general coding of assembly are defined. The assembly is described from three aspects: name category, shape and size, and assembly complexity. The common assembly of shafting and the assembly of box are further subdivided and specialized coding is carried out, and the assembly name and coding are the main key features, and the assembly sequence knowledge base is retrieved. A step by step loosening of matching conditions is used to retrieve similar assembly parts. After matching and mapping corresponding identical or similar parts, the new assembly sequence planning is completed and the database is updated. In the database, in order to define the distance between two root-assembled binary trees, Robinson-Foulds distance and its specific form of deduction and application are introduced, as well as the matrix coding method of root-assembled binary trees. Taking a classical mechanical product as an example to illustrate the assembly sequence planning process proposed in this paper, based on the CATIA platform and its secondary development technology, this paper introduces the principle and flow of the research system, and develops part of the functional module KASP.
【学位授予单位】：华中科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TG95

【相似文献】