Research On Risk Scheduling Method Of Body-in-White Welding Production Line For Equipment Sudden Large Fault

With the increasing diversification and individualization of the demand for automobiles,multi variety and small volume flexible mixed-flow production methods are replacing large scale production models of single varieties,large quantities,continuous and lack of flexibility,resulting in mixed production of body-in-white welding production line.The scheduling process is becoming more and more complicated.At the same time,the manufacturing enterprise does not take into account the probability of equipment sudden large fault and the serious risks brought about by it.If the scheduling model is established according to the determined environment during the planning and scheduling process,it is difficult to reflect the actual operational risk level of the body-in-white welding production line.It is even more difficult to coordinate the planning and scheduling strategy from a global perspective of safety,economy and risk.This paper support by National Natural Science Foundation of China-"Research on Performance Prediction and Optimization Method for Semiconductor Manufacturing Systems Based on Variability(approval number: 71671026)",with the body-in-white welding production line as the research object,improves the problem of not considering the risk of equipment sudden large fault in the planning and scheduling process,and research around the following aspects:Firstly,aiming at the characteristics of the body-in-white welding production line equipment,the sudden large fault state is introduced in the health state of the equipment,and the equipment health state assessment framework is constructed.The hidden Markov model is used to evaluate the health status of the equipment and determine the probability that the equipment is in a sudden large fault state.Secondly,by analyzing the different risks of equipment in different fault states,the gray cluster is used to evaluate the equipment’s conventional fault risk and the conditional risk value model to evaluate the equipment’s sudden large fault risk.Then according to the probability that the equipment is in the state of sudden large fault,the entropy weight method is used to determine the weight of the risk index,and the risk of equipment fault in the body-in-white welding production line is comprehensively evaluated to provide a basis for risk scheduling.Finally,aiming at the process characteristics of the body-in-white welding production line,a vehicle scheduling problem model with station load balance and equipment fault risk as the optimization target is established.A scheduling method combining differential evolution algorithm and multi-objective non-dominated genetic algorithm is proposed.Solve the risk scheduling problem of the body-in-white welding production line.Based on the above research foundation,this paper realizes the prototype system of the body-in-white welding production line for equipment sudden large fault,and selects the actual production data for scheduling optimization.The content of this research has theoretical guidance and practical application value for the comprehensive assessment of equipment fault risk and risk scheduling of body-in-white welding production line.