Research And Implementation Of PLM-oriented Product Structure And 2D Engineering Drawing Difference Comparison System

In the production activities of enterprises,in order to improve the reusability of technical data,conduct version management,etc.,it is often necessary to compare two product architecture trees and the drawings of related components,or to accurately point out the difference.How to complete comparative tasks quickly and accurately is one of the key factors to improve work efficiency and reduce business costs.In this thesis,the PLM-oriented product structure and 2D engineering drawing difference analysis system studied is designed to meet this demand.The basic structure of the system is constructed in the thesis.The product structure comparison,the comparison of the two-dimensional engineering drawings,and the comparison of the two-dimensional engineering image comparison of the core functional modules of the system are established.The key steps in the creation of the product structure tree are studied.The data requirements for the product structure comparison are analyzed.The product structure comparison algorithm based on the intermediate memory database table is designed.A method of displaying the difference of the product structure node in the form of tree structure is proposed,and the function of grid difference information data line and tree node positioning is designed.Then,the main points of the BMP image meshing and the pixel-by-pixel comparison are analyzed in detail,and the pixel-based drawing comparison algorithm is designed.A pixel-level difference display method is proposed and the dislocation,perspective and other drawings browsing mode are achieved.Then the characteristics of the graphical element type are analyzed.the structure of the pixel tables are constructed,and the process of extracting pixel information is explained.The concept of pixel matching tolerance and pixel translation scaling are introduced.Then the pixel-based comparison algorithm and comparison interface are designed.The implementation environment,development tools,and some key points of the implementation of the difference analysis system are introduced.Taking the analysis of product drawing information of two shaft component families as an example,the application workflow of the difference analysis system in PDM system business is Demonstrated.The utility of the system is verified,and the invention patent authorization of the key technology of the system is obtained.