Decomposition of Petri Nets for Optimization of Routing Problem for AGVs in Semiconductor Fabrication Bays

In this paper, we propose a decomposition and optimization method for Petri nets to solve routing problems for automated guided vehicles in semiconductor fabrication bays. An augmented Petri net model is developed to represent concurrent motion for multiple AGVs. The routing problem to minimize total transportation time is formulated as an optimal firing sequence problem for the proposed Petri net. The optimization model is decomposed into several subproblems which can be solved by Dijkstra's algorithm in polynomial order. The effectiveness of the proposed method is evaluated by several numerical examples