Cellular Automaton For Traffic Flow Problems

Cellular automata (CA) is nonlinear dynamical system in which space, time and state values are discrete. By using simply rules, CA has attained very good results in simulating variable complex natural phenomena and physical problems. Firstly, we introduce the recent studies on traffic flow,which based on the statistical physics,such as some theoretical approaches,study models,their instructive significance and limits in practice. Secondly, ,we study an improved Nagel-Schreckenberg model with open boundary condition. We analyze the influence of the boundary condition,safety distance and deceleration probability to the traffic flow. Thirdly,we propose the three branch road modle without control for the Confluence phenomena of cars. We also analyze the influence of the boundary condition,safety distance and deceleration probability to the traffic flow. Finally, we propose an crossroad modle. This model is made up of one main road and one branches:traffic with lights placed on the crossing,vehicles' breaking while running and turning to other direction while jamming.We investigate the velocity and flow of the model when the initial density,the brake and turning probabilities,the green to signal ratio are changed.Then the reasons causing all the kinds of phenomena are analyzed. Thus it proposes the performance for the real traffic control.