Research On Disassembly Sequence Generation And Evaluation Method Based On Matter-Relation Disassembly Model

With the rapid economic growth,resources and environmental issues have been become increasingly severe.Realizing the dismantling of scrapped products were effectively improved resource utilization and reduce environmental pollution.It is an important means to improve corporate social and economic benefits.For the current disassembly model information is not perfect expression,considering the impact of a single factor,the low efficiency of the disassembly sequence planning and evaluation program subjective and other issues,this paper was used the extension of the basic element theory to establish matter-relational element disassembly state disassembly diagram model,and build a multi-factor Under the constraint degree function,the disassembly sequence was generated by the particle swarm algorithm,and finally the feasible disassembly sequence was evaluated by using information entropy.Research contents of this thesis are as follows:1.According to the main factors affecting the disassembly of parts and components,the features of the minimum disassembly unit and the constraint relationship were extracted,and each feature was quantitatively described.According to the extension matter element theory,disassembled element and constraint relation elements were established,and the disassembly diagram model of matter element-relation element constraint state was constructed based on graph theory.Finally,the disassembly diagram model of matter-the constraint state matrix.2.Based on the demolition of the element and restraint relation elements,the factors influencing the disassembly sequence planning were further analyzed.By using the basic peripheral shape features,material features and weight features of the parts in the matter element,the concept of form-ratio was proposed describe the complexity of parts shape with idealization,and establish the disassembly distance calculation method by analyzing the general disassembly process of the product(from outside to inside,from one side to the other side),and disassemble the disassembly tools in the constraint relation element.The level was calculated by disassembling the calculation formula of cost.Finally,the standardization of the above factors were affected the amount of value,the construction of a comprehensive constraint function.3.According to the constant change of the constraint state matrix in the disassembly process,a disassembly operator was constructed,and the particle swarm evolution rules were redefined to adapt to the discrete characteristics of disassembly sequence planning.Then disassembly operators and constraints were used.The state matrix constructs the fitness function of the particle and realizes the automatic generation of the disassembly sequence.4.The assessment indicators of the disassembly sequence were divided into three categories: technical indicators,economic indicators and environmental indicators.The evaluation methods corresponding to each indicator are given respectively.According to these evaluation methods,each disassembly sequence is evaluated and evaluated.After the value is standardized,an evaluation index matrix is established,and then the weight of each evaluation index is obtained by using the calculation method of information entropy.Finally,the comprehensive evaluation value of each disassembly sequence was obtained.According to the above theoretical method,the worm gear reducer was taken as an example for analysis.The results were demonstrated the feasibility and effectiveness of the proposed disassembly model and disassembly sequence generation and evaluation methods.