Design And Research Of A Self-Adaptive Actuated Control System For Tram Arterial Intersections

The line and station layout and signal control methods of modern tram have an impact on the efficiency of social traffic. The traditional tram signal priority control method declines the passage efficiency of conflict traffic. The existing signal priority control system mainly considers traffic priority of public transit mode instead of the passage right of all transit means. This paper proposed an equalized actuated control method to timely adjust signal phase time by detecting queuing situation at each entrance of intersection. The queuing situation can be represented by passage right value. As a medium freight transit mode, modern tram is assigned with a heavy passage right value according to its high ridership. Similarly, social traffic has its own passage right value. The queuing situation can be estimated by accumulating the passage right values. The setting of passage right value to different transit modes assigns the passage right equally to each individual, which gives consideration to each individual’s right. Social traffic is more flexible than tram because tram runs on fixed rails. Equalized actuated control could enhance the flexibility of social traffic and avoid affecting its passage efficiency, and at the same time, give more passage right to the modern tram. Meanwhile, the actuated control system can adjust the queuing situation, solve traffic emergencies and avoid traffic congestion. A single intersection model was established with a traffic simulation software. The equalized actuated control method is applied to this model and data concerning queuing situation, travel time and so on is analyzed by data analysis software. The result shows the equalized actuated control system has an advantage over the pretimed control system.Tram lines are mostly set on urban arteries. As a consequence, the equalized actuated control method for single intersections can be applied to the arterial control system and then develop a new control method which is arterial self-adaptive actuated control. As the equalized actuated control method is a real-time control method based on queuing situation, each intersection can self-organize timing plan to realize efficiency maximization. The arterial self-adaptive actuated control method is developed from single point control to line control. As the traffic volume at intersection, the traffic turning, the traffic running character and traffic volume on segment are completely stochastic, the intersections on the artery cannot be controlled by a fixed pattern.In order to avoid second stop of tram at intersections with tram station, this paper established a conditional priority control system for trams, so as to ensure that trams pass the intersection without delay and to enhance passengers riding experience. When there is no tram passing the intersection, the intersection remains to perform the equalized actuated control system.An arterial self-adaptive actuated control model was established to have a comparison with current arterial progressive coordinated control method which is widely used around the world. Through analyzing the travel time delay, the stops and stopped time of tram and social traffic respectively, this paper proved the arterial self-adaptive actuated control method has an advantage over the arterial coordinated control method. Besides, the simplicity of the control logic and data processing makes the arterial self-adaptive actuated control more practical and easy to realize.