Research On Planning And Scheduling Method Of Complex Flexible Assembly Job Shop

Under the influence of force majeure factors such as the epidemic,in order to realize the independent control of the industry chain,the group companies are turning to a vertically integrated layout with supply chain security in mind,gradually tending to unify the key components of their multiple OEMs to the internal shared production workshops of key components to coordinate production arrangements or outsourcing.In the actual production environment,the impact of demand fluctuations in OEMs will further spread to the shared production workshops of key components that are closely linked downstream,resulting in more obvious fluctuations in workshop demand.The production mode of key components is multi-variety and small-lot,and the production schedule of parts with assembly linkage is highly synergistic,which leads the workshop to consider not only multi-level outsourcing for capacity adjustment to adapt to the changing environment,but also the sharing of parts between different products.In addition,the shared production workshops of key parts are generally equipped with highly flexible equipment resources to meet the various processes of differentiated parts,which undoubtedly further increases the difficulty of workshop planning and scheduling.The shared production workshop for key components can be abstracted into a type of flexible assembly job shop that considers multi-level outsourcing.The vast majority of classical related studies focus on shop scheduling without considering parts sharing and outsourcing,and there is a lack of studies related to order release planning considering forward-looking shop capacity planning,but such shops need both order release planning with outsourcing foresight and dynamic shop scheduling with schedule synergy.To that goal,the following parts of this thesis have been researched:（1）Aiming at the current situation and difficulties of production planning and scheduling management in flexible assembly job shops,an integrated framework of order release and dynamic scheduling is proposed.Based on the integrated framework and the overall business process,the main functional requirements of the planning and scheduling integrated system are designed.（2）A probabilistic discounted load estimation method is constructed for the order release planning problem in the flexible assembly job shop,and an order release model considering product outsourcing is established with the objective of minimizing the sum of work-inprocess holding cost,order delay cost,product inventory cost,and product outsourcing cost,and finally the validity of the model is verified based on the solver.（3）Aiming at the dynamic scheduling problem of flexible assembly job shops,with the optimization goal of minimizing the cost of product delay,the cost of waiting for parts complete sets,and the cost of parts outsourcing,a workshop scheduling model considering parts outsourcing is established,and a periodic rolling scheduling algorithm P-GAIG based on a hybrid genetic algorithm and an iterative greedy algorithm is coupled with a parts sharing strategy based on the tightness of delivery.Finally,the effectiveness of the algorithm is demonstrated by simulation experiments.（4）Based on the above research on the order release and dynamic scheduling method,a flexible assembly job shop planning and scheduling integrated system is designed.On the basis of integrating the existing information system,the system functions,workflow and application examples are described.