关键词: 柔性作业车间调度, 运输约束, 改进NSGA-II算法, 车间调度算例

Abstract: Traditional flexible job shop scheduling usually ignores the transportation time and energy consumption of workpieces between machines.To solve this problem,a flexible job shop scheduling model by considering transportation constraints and energy saving was established,and an improved fast elitist Non-dominated Sorting Genetic Algorithm(NSGA-II)was proposed to solve this model.Four goals of maximum completion time,total delay,total equipment load,and total energy consumption of the workshop were established in the mathematical model of flexible job shop scheduling,and the scheduling model matrix encoding,decoding,crossover and mutation were realized according to transportation constraints.It is easy to fall into the problem of local optimal solution in the iterative process of improving NSGA-II algorithm by learning from the optimal solution mechanism.Under the premise of considering the transportation constraints between machines in the workshop,the feasibility analysis of the scheduling model was carried out in combination with the Kacem and Brandimarte examples.The results showed that the model and algorithm were highly efficient and could effectively solve the scheduling scheme and actual processing deviation caused by the workshop transportation constraints.

Key words: flow shop scheduling, transportation constraints, improved fast elitist non-dominated sorting genetic algorithm, workshop scheduling examples