Research On Key Technologies Of Intelligent Design Platform For Agricultural Machinery Parts Based On CAD Model

China is a big country in agriculture and agricultural machinery manufacturing industry,but the agricultural machinery industry in China has the characteristics of low industrial concentration,single product structure,backward manufacturing technology and equipment level.Establishing an intelligent design platform for agricultural machinery components based on CAD model is conducive to improving the efficiency of agricultural machinery research and development,upgrading the overall collaborative ability of the industrial chain,and strengthening the level of industry innovation.Intelligent design platform for agricultural machinery components should include rapid design module,rapid modeling module,intelligent reasoning design module and simulation design function.At the same time,in order to ensure universality,the platform should be able to handle multi-source heterogeneous models.In order to ensure practicability,it is necessary to dock PLM(Product Life-cycle Management)and data update function.This paper will analyze,discuss and implement the key issues of the design platform.The contents and innovations of this paper are as follows:1.In order to ensure that the platform is universal and efficient,the three-dimensional model transformation module is completed.A new method of three-dimensional mesh model transformation,model dissector-abstract grammar tree(P-AST),is proposed.This method solves the problem that traditional one-dimensional semantic mesh model transformation can not achieve semantic missing and multi-directional rotation.At the same time,two methods are proposed to detect the data loss rate and model closure of the transformed model.2.In order to achieve rapid reuse design and model retrieval,similarity matching of models is carried out by extracting feature subsets of three-dimensional models.Combined with weighted Euclidean distance algorithm,the similarity detection of three-dimensional model is realized.Finally,the rapid reuse design of the three-dimensional model is completed.3.Build an independent embedded rapid modeling module,which solves the shortcomings of traditional fast modeling software based on secondary development,which relies too much on the source software core,and can seamlessly access the intelligent design system.4.In order to realize the intelligent design module,the knowledge in agricultural machinery design is classified,and different types of knowledge are produced in different ways,and a complete knowledge base is constructed.Intelligent reasoning module of the platform is constructed by combining real model with hybrid model in agricultural machinery design,and improved D-S evidence theory is introduced to solve reasoning conflict mechanism.5.In order to ensure that the software itself has both practical value and scientific research value.Finally,the above functions and algorithms are integrated into the unified software,and the optimization of Surface,Skeleton,Scope and Structure is carried out.At the same time,the interface between data stream and PLM is extended.