Signal Coordination Control Method Based On Optimizing Speed For Transit

As a usual method in giving priority to transit efficiency, signal priority control plays as a major role in improving transit service level and increasing public transit sharing ratio. However, transit signal priority may influence the efficiency of passenger cars, so it is significative to improve the efficiency of transit vehicles while the efficiency of passenger cars can be guaranteed.This paper focus on the study of signal coordinate control scheme for passenger cars to guarantee their efficiency. To improve the efficiency of transit vehicles, we designed a scheme to optimize speed for transit vehicles. Then we can realize the purpose of improving the efficiency network and reducing emissions.First, by analyzing the arrival and departure character of vehicles in intersection, we proposed a simplified algorithm based on arrival-departure curves to analyzing emissions, and realized the consideration of emissions in the process of calculation. Then an elitist non-dominated sorting genetic algorithm is used to solve the signal coordination scheme for passenger cars.Second, on the basics of green light optimal speed advisory strategy, an optimal method for speed of transit vehicles is proposed, which considered the factors of berthing time, lost time coursed by entrance and exit bus stop.Third, based on the micro-simulation simulator software of VISSIM, three modules including speed optimization before stop, extension of dwell time, and speed optimization after stop are designed by the programming language of Visual Basic Script.Finally, a comparative analysis for optimized signal coordination scheme is made according to data investigated in field. And a comparative analysis for the effect of speed optimization in different transit volume and different distances when starting optimization is made. The result shows that the comprehensive control scheme can reduce emissions and fuel consumption by 16.67%, and can reduce travel time of transit vehicles by 12.3%. which is significant in improving the emissions and efficiency of vehicles.