Study On Coordinated Control System Of Far Lead Mid-block Actuated Pedestrian Crossing Signal

The problem of urban traffic congestion has become a focus point that is urgently needed to solve and hard to avoid in the development of cities around the world.In practical research,traffic congestion generally occurs on the single-point control section of the city,therefore the domestic and foreign scholar has summarized and proposed the theory of arterial coordination control,however,in addition to the need to solve the coordination control between adjacent intersections,the traffic congestion problem in the arterial segment also needs to be solved,and the congestion in the mid-block generally occurs on the crosswalk.The characteristics of the fixed-time signal control cannot respond to the traffic demand of traffic flow in time,and it is easy to increase the waiting time for pedestrians,the development of actuated signal control and its own adaptability make its advantages more obvious.However,although single-point control has been optimized,in practice the mid-block pedestrian crossing signal in China have little or no coordination with adjacent intersections,Therefore,it is difficult to avoid the contradiction between the mid-block pedestrian crossing and the traffic of arterial.For this purpose,it is necessary to use a coordinated control technology to harmonize the two control modes.This paper proposes a study on coordinated control system of far lead mid-block actuated pedestrian crossing signal.By combining the optimization of the single-point signal control with the coordinated control technology,the reduction of pedestrian crossing waiting time can be realized,and at the same time,it can ensure that the urban arterial provides enough bandwidth to meet the safe passage.The main contents of the full paper are as follows:(1)Determine the setting distance of far lead push button.The determination of the distance mainly depends on the relationship between the extension time of vehicles phase and pedestrian walking speed.Based on the control logic diagram of actuated pedestrian crossing signal to determine the three indicators for time description,the speed is determined mainly through the traffic survey of the actual status and statistical analysis software to select the 15% speed and 85% speed of the pedestrian and traffic flow as the design speed.(2)Study the characteristics of green band distribution characteristics at different position.Considering the limit waiting time and the determined far lead distance,this paper analyzes five different time-space patterns at different position under the determined green wave bandwidth and proposes a specific location distribution model.(3)Establish a green band model of adjacent intersections.Based on the idea of Ring-Barrier,a coordinated control model is established,the North-South direction is used as the optimization direction.At the same time,the actuated green wave coordination is carried out by combining the location model,the MAXBAND model,and the coordination control model.(4)Design control logic of far lead mid-block actuated pedestrian crossing signal.Combining the green band distribution characteristics at five different position,the system can make correct and timely response when the pedestrian push button under the determined green wave bandwidth.(5)Example design and simulation verification.It mainly includes two parts:(1)In order to determine the position of the far lead push button,calculate the theoretical distance according to the three calculation methods,at the same time,to verify the effect of the selected distance on pedestrians crossing,the waiting time of pedestrian is used as an evaluation index,and the VAP module in the VISSIM is used to simulate;(2)Take the two pedestrian crossing in the Shanxi RoadXinmofan Road section of Zhongshan North Road as an example,and use the Synchro to simulate,the average delay o and the parking rate f vehicle is used as the evaluation indicators to compare the three control schemes to analysis and evaluation,which includes the current configuration time,the coordination control model and the optimized position.