Study On Logistics Distribution Time Model Considering Road Traffic Flow And Signal Light

In recent years,China's social economy has developed rapidly,the urbanization process has advanced rapidly,the number of motor vehicles has increased sharply,the speed of urban transportation facilities' building has been unable to meet the transportation needs of vehicles,and the road traffic environment and traffic rules such as traffic density and signal lights have begun to become Factors affecting the efficiency of automobile transportation.How to maximize the use of existing road traffic facilities and improve the transportation efficiency of automobiles has become a hot issue in the field of traffic management.In the research of road transportation,transportation time is an important indicator to measure transportation efficiency.Less transportation time can increase the transportation efficiency,and reduce the oil consumption or other loss,especially in the event of disasters.During the emergency rescue,we need to evacuate the affected people in time,transport relief personnel and emergency supplies rapidly.If we beyond effective rescue time,it would lead to huge losses in life or property.Forecasting the travel time on the road can not only help the macro-control of traffic managers at all levels,but also provide reference for the travel choices of ordinary pedestrians.From the perspective of transportation time,this paper uses macroscopic traffic flow model to predict road transportation time,deeply excavate the essence of traffic flow,study traffic evolution law,reveal the influence mechanism of signal light on automobile transportation time,and explore the method of using traffic light collaborative control to improve transportation efficiency.The main process includes: First,build a transport time prediction model.Divide the transit time of a car into the travel time on the road and the waiting time before the signal light.Calculate road travel time by using the relationship between traffic speed and road traffic flow density.Comparing the signal light cycle and the time before the car reaches the signal light to get the waiting time of the car.Transportation time is obtained by adding the travel time and the waiting time.Then,using the established macro traffic flow model to simulate the transportation process.Simulate under the ideal conditions of the same road segment length and uniform change of signal lights.Through the control of traffic flow density,number of signal lights,cycle time,green letter ratio and other parameters,explore the impact of various parameters on transportation time.Finally,based on the simulation results,optimize the transportation time,and propose the optimization strategy based on green wave control.Research shows: The red light time of signal light will compensate the travel time of the car on the road,so that the curve of transportation time with the traffic flow density will become ladder shape.After introducing such factors as the number,cycle length and green signal ratio of the signal light,such ladder curve will change with the parameters of the signal light.It is feasible to use the time difference to optimize the transportation time.The optimal phase difference between the traffic lights on the transportation path can be calculated based on the signal period and traffic density.But,as for the specific implementation,detailed control of the signal system is required.