Heterogeneous Traffic Flow Modeling and Simulation Using Cellular Automata

This study presents an attempt to simulate heterogeneous traffic using the principles of cellular automata. A conventional cellular automata mode for the homogeneous traffic is modified to handle heterogeneity. The principle adopted in this study is to retain the passenger car equivalent concept of HCM and the basic structure of the CA model. The modifications are done at three levels: First, the cell size is reduced to take the concept of passenger car equivalents. Second, the randomizing rule is modified to suite heterogeneous traffic conditions. Finally, the lane changing rules are modified to handle over taking maneuvers and conditions different types of vehicles characterized by their dynamic characteristics. The models were calibrated and validated with limited data sets and the performance of the model is presented.