Research On High Flexible Numerical Control Manufacturing Cells Formation And Scheduling Of Complex Electromechanical Products

Currently due to the rapid development of aviation,aerospace,high-speed railway,and other high-end manufacturing industry,the complex electromechanical products(CEP)company is facing multi-varieties and small-batch production along with shorten manufacturing cycle.This situation makes the production organization and management more complex,where manufacturing system cannot response efficiently and effectively to the market demand.Hence,a range of enterprises introduce manufacturing cells(MC)to meet multi-varieties and small-batch production.As an important and flexible method to improve efficiency,several enterprises begin to introduce high flexibility numerical simultaneously.Because of this,the formation and scheduling of high flexible numerical control MC were the basic problem that must be solved,and it is also the best way to improve high-end manufacturing capacity of the country.By considering the current situation of formation and scheduling about CEP,the formation and scheduling of high flexible numerical control MC was carried out in the present thesis.Furthermore,main research contents are following described.(1)Focus on the CEP,processing and production characteristic were analyzed,along with manufacturing flexible constitute element and action mechanism of high flexible numerical control MC were also presented.Afterward,the whole framework of formation and scheduling were proposed based on CEP high flexible numerical control MC analysis.(2)A high flexible numerical control MC formation model was proposed by considering machine weight and uncertain demand,a two layer chromosome genetic algorithm(GA)is designed to solution the result.A aerospace workshop of CEP high flexible numerical control MC formation as a case study,and analysis the result of formation with classic two-stage MC formation method,verified this paper' MC formation method can meet the uncertain demand and flexible manufacturing.(3)A two-stage scheduling method based on balancing takt of electromechanical parts high flexibility numerical control MC was proposed.First,the process planning was established consisted on process characteristics and machine capacity,and subsequently the balancing takt as an optimal processing views combination was achieved on the basis of considering the preparation time,machine capacity,and processing sequence.Second,,the product scheduling models which considered the product changeovers time was proposed based on balancing takt result and parallel translation model,then a genetic algorithm was proposed to solve the model.Lastly,a aerospace shell high flexibility numerical control manufacturing cell as an example,a comparative variable batch scheduling model,and two-stage scheduling based on balancing takt was conducted.Through the studies,A two-stage scheduling method based on balancing takt can meet the flexible MC production and multi-varieties and small-batch production.(4)Because of the high value,the key role and high delivery time of lots of CEPs,the scheduling should be considering in parallel collaborative of multi-manufacturing cells,so thant an parallel collaborative scheduling model was presented,and a segment parallel collaborative genetic algorithm is also designed.Finally,the model is tested in a aerospace workshop of CEP which has some MCs,and a comparative batch scheduling model which has some MCs,and parallel collaborative scheduling model was conducted.Through the studies,the parallel collaborative scheduling can meet the multi-varieties and small-batch production.