Dynamic Graph Hybrid Automata: A Modeling Method for Traffic Network

The paper proposes a modeling method, which is called Dynamic Graph Hybrid Automata (DGHA), to describe the evolution law of traffic flow over a road network. In the model, the traffic dynamics are described by the Modified Cell Transmission Model (MCTM), where the cells are expressed by hybrid automata, and multi-mode switching expressions are introduced to the connections among these cells. The proposed DGHA models are modularized and easily-extensible, and are implemented by Modelica language on the OpenModelica. By using the modeling method, one can establish traffic flow network models with any topology structure. Two simulation examples show the effectiveness of the proposed modeling method.