Colored Petri net based hierarchical scheduling model for semiconductor production line

In this paper a kind of scheduling model and its modeling approach are studied for reentrant semiconductor production line. By introducing multi-dimensional color sets and machine group oriented hierarchy, a kind of colored Petri net based hierarchical scheduling model is proposed. Then, a case study of the proposed model is illustrated with an example semiconductor production line, which includes 5 machines and 6 steps. The modeling approach is combined top-down structure modeling and bottom-up parameter definition. At last, some further discussion about the application of the proposed Petri net model are given.