Research On Flexible Job Shop Scheduling Considering Workpiece Deterioration Effec

With the continuous upgrading and iteration of manufacturing technology,the production mode of enterprises has undergone major changes,and the flexible operation workshop has gradually replaced the original production mode with its advantages of strong adaptability,high production efficiency and high resource utilization.In traditional shop floor scheduling studies,machining time and machining factors are usually set to fixed values,and less research is done about changing machining times,but in actual production.At the same time,with the implementation of green manufacturing,it is urgent to implement effective energy-saving measures in workshop production.Therefore,it is very important to study the problem of flexible work workshop scheduling under the deterioration effect of workpieces.Based on the flexible job workshop scheduling model,this study establishes a model covering five scheduling optimization goals in view of the impact of workpiece deterioration effect and energy-saving measures of shutdown/restart,and improves the chimpanzee optimization algorithm according to the model characteristics,and finally adopts the multi-objective decision-making method to make scheduling scheme decisionmaking,which achieves good application results.The main research contents are as follows:(1)In view of the influence of the deterioration effect of the workpiece,taking the flexible operation workshop as the research object,considering the workshop energy consumption of the machine in different states,the scheduling model under various optimization objectives is established.An improved Chimp Optimization Algorithm is proposed for solving,and firstly,the ROV rule is used to establish the transformation mechanism of continuous algorithm and discrete problem in the coding stage.Then,the initialization method of GLR is used to improve the quality of the initial solution.Then,the individual update method and variable neighborhood search with dynamic weights are adopted to avoid falling into local difficulties.Finally,fast non-dominated ranking and elite selection strategies are introduced to solve multi-objective workshop scheduling problems.(2)In the long-term processing process,the machine’s long standby time will produce unnecessary energy consumption,so consider the energy-saving measure of shutdown/restart strategy,and determine the threshold time point for implementing the strategy by comparison.At the same time,the empowerment method of AHP-EWM is proposed,and the comprehensive evaluation of multi-objective problems is carried out in combination with the TOPSIS method,so as to select the most suitable scheduling scheme.(3)The effectiveness of the improved algorithm in single-target problem and multi-objective target workshop scheduling problem is verified by extended standard example,and the correctness of the model is also verified.Secondly,through the example pair,it is verified that energy-saving measures can effectively reduce carbon emissions.Finally,the specific production example of an auto part is used to solve the problem,and the proposed multi-objective evaluation method is used to select the scheme,which verifies the practicability of the decision-making method.