Research On The Integrated Model Of Process Decision And Scheduling Based On Super-network

Process planning and workshop scheduling are two important systems of the workshop manufacturing system,and the two are mutually traction and mutual constraints.Process planning is the basic work of workshop scheduling,which determines the greatest possibility of optimizing the degree of workshop scheduling scheme,and workshop scheduling is an inspection work to measure the reliability of process planning and ensure the effective implementation of process planning.Therefore,the view that process planning and workshop scheduling are completely separated and that the two are only serial in chronological order is contrary to the trend of integrated development of modern manufacturing systems.However,there are also many difficulties in the integrated development of process planning and workshop scheduling,and the reason for the integration difficulty is that the information asymmetry of the process planning system and the workshop scheduling system,and the respective information systems serve their own local decision-making and lack the overall consideration of the entire production process.Information is the basis for decision-making,and if the production process data can be grasped globally,it will be conducive to the overall decision-making of the production process.With the continuous growth of workshop production scale,the wide application of workshop automation equipment and the in-depth development of Internet of Things technology,the workshop has accumulated a large amount of historical manufacturing data,fully excavated valuable historical information,and applied it to the manufacturing system,which will provide the possibility for the integrated development of process planning and workshop scheduling.The existing research on the integration mainly focuses on workshop feature flexibility,operation flexibility and machine flexibility,this thesis considers that the influencing factors of workers on the production process cannot be ignored,increases worker flexibility,studies the integration of process decision-making and scheduling,takes the feature,operation,machines and workers as key elements to establish the workshop manufacturing supernetwork information model and establishes the operation time prediction model based on historical data,and finally establishes the process decision-making and scheduling integration model based on the super-network,and designs the corresponding algorithm to solve it.1.Aiming at the problem that the information of the process planning system and the workshop scheduling system is difficult to synchronize,the super-network technology is introduced to extract the key element features,operations,machines and workers of the processing process as the key elements of the super-network,and the super-network information model of workshop manufacturing is established to provide an information basis for the integration of process decision-making and scheduling.2.Aiming at the problem of uncertainty in operation time in the actual production environment,the factors affecting the operation are taken as input,and the LSTM neural network is used to train historical manufacturing data to predict the operation time.In view of the characteristics of uneven time intervals presented by operation time,a time control gate is added to the LSTM cell structure unit to further enhance the reliability of the prediction model,and the predicted operation time of the model will be used as the processing time parameters of the subsequent process decision-making and scheduling integration model.3.Based on the super-network,the process decision-making and scheduling integration model is established,and four sub-problems of feature selection,operation selection,machine selection and worker selection are integrated.Aiming at the solution of the model,a two-stage hybrid genetic algorithm integrating process decision and workshop scheduling is proposed.The task of the process decision-making stage is to select features and operations,so the bilayer matrix coding chromosomes corresponding to the features and operations are designed;The task of the scheduling stage is to select operations,machines,workers,so the machine chromosomes and worker chromosomes based on the operation are designed.