Evaluation Of Transit Priority Strategies On Intersections Based On Cellular Automata Modeling

With the urban traffic congestion growing, public transport has increased its status in the urban transport system, and bus signal priority has become an important part of traffic signal control systems. The impacts of the transit signal priority control to general social vehicles and environment of intersections are worthy of studying. In this article, transit signal priority strategies for intersections under the condition of mixed traffic flow are analyzed,and integrated constraints, spatio-temporal constraints and resource constraints are established on active priority control. Based on cellular automata theory, the simulation program are taken for analysis of traffic flow at intersections. Specific elements include the following:(1) the bus signal priority strategy optimization. Summarizes the characteristics and applicable scope of passive, active, the absolute priority priority priority, priority strategy of bus signal priority, priority strategy and the condition of single object and multi object refinement are described by two; imports transit vehicle location decision, the improved multi- phase bus signal priority response process to the bus; the number, the average vehicle delay, queue length and other variables as the optimization index, based on the consideration of bus priority traffic benefits both the whole intersection, bus signal priority model is established for time and space constraint conditions; in the analysis of the vehicle in the acceleration and deceleration, idle speed of different driving conditions, the calculation method of energy consumption and the exhaust emission and other indicators in the constraint conditions of, respectively, and the resource constraints for the optimization goal, establish the resource constraints of bus signal priority strategy.(2) the establishment of the intersection of cellular automata simulation model. The import Road intersection mixed traffic flow characteristics were analyzed, using TT model and the VDR one-dimensional cellular model as the foundation, considering the factors of the vehicle and the leading vehicle speed slow start, VDR model is set up based on the classical model; change the symmetry, the vehicle steering, the improved multi- lane the symmetric lane changing model; established the intersection turn left, turn right, go straight and steering vehicle operation rules of traffic flow, so as to establish a cellular automaton model of mixed traffic flow at intersection bus priority signal control.(3) the correlation between each index constraints on time and space constraints and resources condition analysis, the two kinds of constraint combination, established a number of public transport vehicles, the average vehicle delay, vehicle energy consumption for signal control model under resource constraints. And to set the environmental conditions of intersection as the foundation, through programming method of bus signal priority control strategy are simulated by using MATLAB software, the analysis of simulation results, the comprehensive constraints bus priority strategy can better balance the public transport vehicles and vehicles benefit, and keep the change of relative stability in terms of energy consumption and pollution emission.