Research On Bus Priority Intelligent Signal Control System At An Intersection

Bus priority is an important component of the advanced public transportation system in the intelligent transportation system; it is one of the effective ways of alleviating the city traffic problem.The dissertation has proposed a kind of implementing scheme of Bus Priority Intelligent Signal Control System. The system is made up of vehicle detection subsystem, bus detection and location subsystem, intelligent signal controller, communication subsystem, and system control center mainly. The vehicle detection subsystem uses loop vehicle detector. The bus detection and location subsystem uses the beaconing location technology. The intelligent signal controller accomplishes real-time and adaptive traffic control. The communication subsystem accomplishes the communication among every part in the system. The system control center accomplishes the correlation and integration among subsystems.In the system, bus priority intelligent signal controller considers bus PRI and flow quantity of all vehicles synthetically, calculates the eager degree of the red phase and the change degree of the green phase. Then according to the fuzzy rule storehouse, which set up on the basis of the practical experience that traffic-police command the traffic, it processes an intelligent decision-making by the fuzzy inference system, then gets the prolong time of the green signal at the next switch time, and achieves the automatic and real-time change of the green signal time.Finally, the dissertation has researched on the simulation experiment of the system; it simulates the traffic running situation at a four-phase cross-type intersection, adopts the fixed-time control mode and the bus priority intelligent control mode to carry on the simulation experiment separately. The experiment result shows that the bus priority intelligent signal control mode can effectively reduce the passengers' average waiting time at the intersection, and achieve the bus priority of the time right-of-way at the intersection. At the same time, the system also can effectively reduce the average waiting time of all the vehicles at the intersection.