A Motion of the Leading Vehicle at Signalized Intersections

This paper explores a kinematic trajectory equation for the leading vehicle at signalized intersection for varying start of green time. The vertical queueing model that is adopted widely in traffic signal optimization assumes that all vehicles have the identical motion. Thus, the departure time of the leading vehicle is assumed to coincide with the start of the effective green time. To overcome the simplicity of the vertical queueing model, more detailed trajectory model is developed based on the one dimensional Kinematic equations in physics and formulated analytically as a function of the start of green time. The results show that the delay estimates in the vertical queueing model is not realistic and always greater than or equal to the Kinematic trajectory model. Though the results shown in this paper are limited to a leading vehicle, the trajectory equation may be extended for many vehicles in relation to the general car-following concept.