Citation

Beeber J. ITE J. 2020; 90(3): 34-38.

Copyright

(Copyright © 2020, Institute of Transportation Engineers)

DOI

unavailable

PMID

unavailable

Abstract

In 1960, Denos Gazis, Robert Herman, and Alexei A. Maradudin (GHM) provided a scientific solution to the yellow change interval question in their paper, "The Problem of the Amber Signal Light in Traffic Flow." GHM presented a kinematic solution to a binary STOP or GO dilemma when a driver is faced with the onset of a yellow signal indication. The problem GHM solved and eliminated was an area in the roadway known as the "dilemma zone", where a driver-vehicle complex could neither STOP safely and comfortably nor GO without the need to violate the red or accelerate unsafely into the intersection. GHM's solution to regulate a yellow change interval first appeared in the 1965 ITE Traffic Engineering Handbook, and it has become known as the kinematic equation. However, GHM's solution is limited to vehicles traveling through level intersections at constant velocity, which does not include vehicle deceleration to execute safe turning maneuvers. This article presents a brief review covering GHM's original solution and Mats Järlström's extended kinematic equation which allows for vehicle deceleration and turning maneuvers.

Language: en

Keywords

Highway safety; Intersections; Traffic signals; Kinematics; Turning traffic; Yellow interval (Traffic signal cycle); Equations; Change interval (Traffic signal cycle); Mats Järlström