Cellular automata simulation for mixed manual and automated control traffic

Abstract

Complex traffic systems seem to be simulated successfully by cellular automaton (CA) models today. Various models are developed in efforts to understand single-lane traffic, multilane traffic, lane-changing behavior and network traffic flow. In this study, four cellular automata (CA) rules for advanced vehicle control and safety systems (AVCSS) are proposed and simulated. The major difference among the rules is the different settings of the gap, which is defined to be the distance between two successive vehicles. The gap of each rule is given depending upon the speed of vehicles. According to the results, CA rules with AVCSS (the H 0, H 1, H 2 and H 3 models) lead to a more stable traffic flow than rules without AVCSS. Also, the average flow and speed for CA rules with AVCSS are larger than the average flow and speed for rules without AVCSS. However, the average speeds of the H 1 and H 2 models fluctuate greatly, which is considered unsafe and unreliable, in a congested regime. The results from the H 0 and H 3 rules are more stable than the results from the H 1 and H 2 models. The H 3 rule keeps a larger gap between two successive vehicles; therefore, the H 3 rule is considered the best design of the four AVCSS CA rules. If a combinative rule is considered, the envelope of the speed–density curves of the four models might provide an optimal design, presenting a larger speed and flow than the H 3 model. Therefore, an efficient design of AVCSS might be obtained by CA simulation.