An example of the results from a fixed-base traffic simulation (VISSIM) using Virtual Test Drive (VTD) software is shown in Figures 1 and 2, which correspond to the results of vehicular emissions calculated with MOVES. The figure illustrates a set of link-instantaneous vehicle speeds and the traveled distance of each vehicle during one hour. The curves on the left column correspond to actual travel time (t), the curve in the middle column corresponds to the travel time predicted by the model, and the curve on the right column illustrates the difference between the actual travel time and the predicted travel time. The initial speed of vehicles is set to 15 km/h. Subsequently, the speed of each vehicle fluctuates around this initial speed until the end of the hour (when the speed of all vehicles reaches their maximum and the vehicles travel at maximum speed), which is at time = 2200 in the figure. The initial road section is a ramp with slope of 1.5 m/km (the same for all vehicles) to illustrate the influence of the initial speed on the vehicles’ trajectories. The initial speed is increased from 10 to 60 km/h and then decreased from 60 to 10 km/h for the first 10 minutes of the hour. The results show that the actual travel time is different from the predicted travel time, which is due to the fact that the vehicle’s initial speed is not the same for all vehicles as they travel different distances, which affects the vehicles’ travel time. This is especially true when the initial speed is decreased (becomes slower), which causes vehicles to travel farther than expected and adds more travel time to the total travel time. Note that the selected road section is neither urban nor rural, but a highway with many intersections.
The results from the VISSIM model without the advantage of virtual test driving are shown in Figures 3-5 in the same order as the figures mentioned above. Figures 3-5 illustrate the same results from VISSIM model as in the previous figures but, of course, the results are not as realistic as those in Figures 1-2. In these figures, the curves on the left column correspond to actual travel time (t), the curve in the middle column corresponds to the travel time predicted by the model, and the curve on the right column illustrates the difference between the actual travel time and the predicted travel time. The initial speed of vehicles is set to 15 km/h.
PTV Vissim is a traffic simulation software solution that provides a simulation environment for microscopic traffic modeling. It is also a framework for integrating other software solutions. By using the Vissim COM API, PTV Vissim allows you to link external software systems to perform advanced analysis and simulations. PTV Vissim works seamlessly with PTV Traffic Suite and other PTV software solutions, including PTV Moves, PTV Move-it, and PTV Multimodel.
This work was motivated by an interest in developing a model which could simulate traffic operations in a highway designed to optimize the safety and efficiency of traffic flows. This paper demonstrates how a model such as VISSIM can be utilized to evaluate the effectiveness of proposed designs in minimizing vehicular emissions. The results show that the VISSIM model can be used to simulate the emission rates in a highway, and the factors that impact the emissions are explained. 827ec27edc