The Research On Integrated Optimization Scheduling Of Mixed-model Fabrication And Assembly System

Mixed-model fabrication and assembly system is hybrid system constituted by job-shop production and flow-shop assembly production.The production is organized around mixed-model line.During the production process,kinds of products are processing in the system,requiring more components to supply.Result in much more constraints in system and closer interaction between sub systems.In this situation,making integrated optimization scheduling for sub systems came to be the critical problem to optimize the production system.This dissertation built optimization models for every level of the system with the features of mixed-model processing and assembly production,and the effective methods and algorithms were proposed in this paper to settle the scheduling problems.The main work and contributions of this dissertation are as follow:1.Research on optimization algorithm for processing production scheduling problem.The job shop scheduling problem represented by flexible job shop scheduling was studied.A hybrid swarm intelligence optimization algorithm base bee colony optimization was proposed to settle the problem with the object of minimum of make-span.The research provided the foundation of follow-up research on integrated scheduling.2.Research on optimization algorithm for mixed-model sequencing problem.The flow shop scheduling problems represented by permutation flow shop scheduling and mixed-model assembly line sequencing was studied.A modified artificial bee colony optimization algorithm was proposed.And with the object of make-span the algorithm was applied to settle the scheduling problem.The research provided the foundation of follow-up research on integrated sequencing.3.Research on mixed-model associated production integrated sequencing problem.A kind of integrated sequencing problem composed by multi mixed-model assembly line with the production and logistics constraints was studied.Base the study on mixed-model sequencing problem,the integrated optimization structures was given,and the integrated sequencing model was built with the objects about stoppage of assembly line,make-span,adjust cost fee of serial sequences and so on.A heuristic algorithm base bottleneck analysis for initialization and the method to adjust production sequence were given.And a local search algorithm based bottleneck analysis is given.Finally,the validity of the methods proposed was tested by applied on a fridge manufacturing example.4.Research on integrated scheduling on mixed-model processing and assembly production.A kind of integrated scheduling problem composed by flexible processing workshop,assembly workstations and mixed-model assembly lines are studied.Considering the batch constraint based the FJSP,the batch scheduling problem of assembly and processing was proposed.And with the mixed-model sequencing problem,an integrated optimization structure was given.And the integrated scheduling model was built with the objects of level scheduling,transport cost fee,buffer storage cost,make-span and flow time cost.To solve the problem,a co-evolutionary strategy is involved in artificial bee colony algorithm to realize integrated optimization of batch and scheduling.Finally,the method's validity was proved in a processing workshop and assembly workshop in fridge manufacturing example.5.The whole research work and achievements acquired in this dissertation was summarized,and the future of the research on scheduling of mixed-model processing and assembly production was given.