Research On Polychromatic Modeling And Reconstruction Of Mechanical Equipment Transmission Design Knowledge

Transmission system is the part of power transmission in mechanical and equipment.With the continuous development of mechanical and equipment,transmission system presents a tendency of complication.The inefficient use of a large amount of design knowledge causes designers to face the problem of "rich data,lack of knowledge".Domestic and foreign scholars are also paying more and more attention to the research of mechanical equipment knowledge reconstruction.This paper takes the knowledge of transmission design of mechanical equipment as the research object,and carries out the research on the method of polychromatic modeling and reconstruction.The research contents include:(1)Modeling of transmission design knowledge based on polychromatic setsAccording to the mechanical design manual to obtain and summarize the mechanical transmission related design knowledge,and then analyze the various components and the type of the transmission system etc.The knowledge level relationship of transmission system design is studied.The design requirements as the unified color,the transmission type as the individual color,the interaction between components as constraints,and the attributes of transmission system as elements,to establish the polychromatic model of mechanical transmission design knowledge.(2)Knowledge reduction method of transmission design based on attribute combination associationThis paper studies how to reduce the relevant,redundant,and incomplete transmission knowledge.On the basis of rough set theory,the evaluation criteria model of knowledge reduction is established by fusing DEMATEL method,mutual information theory and other theoretical knowledge: the objective function is the attribute importance and the correlation between attributes,and the constraint condition is the number of attributes and the number of iterations.Through the established evaluation criteria and combined with intelligent algorithm,the redundant part in the data is eliminated,and the most concise transmission design knowledge is finally selected,so as to realize the reduction and reconstruction of transmission design knowledge.(3)Incremental attribute reduction method of mechanical transmission design knowledgeAiming at the characteristics of fast update cycle and incomplete data of transmission design knowledge data,an incremental attribute reduction method based on attribute frequency and KNN classification algorithm is designed.The original decision table of transmission design knowledge is deeply analyzed,and the incompatible decision table are classified to simplify the original decision table.The relationship between the new samples and the original decision table is analyzed in three cases,and KNN algorithm is introduced to eliminate the inconsistent samples.Taking the frequency of attributes in the identification matrix as the criterion of attribute importance,the redundant attributes can be quickly distinguished and eliminated.(4)Establishment of transmission knowledge reuse systemThe database of transmission design knowledge is established based on the hierarchical division of polychromatic set and attribute reduction.And secondary development of NX10.0 combined with database,the following functions can be realized: It is necessary to consult the mechanical equipment transmission knowledge,design the transmission system according to the requirements,and give certain restrictions to consult the data etc.Thus,a set of relatively perfect mechanical equipment transmission knowledge reuse system is established,which is convenient for designers to use.