Journal of Applied Mathematics
Volume 2012 (2012), Article ID 727839, 13 pages
Research Article

A Platoon Dispersion Model Based on a Truncated Normal Distribution of Speed

Department of Transportation Engineering, South China University of Technology, Guangzhou 510640, China

Received 24 November 2011; Revised 31 December 2011; Accepted 31 December 2011

Academic Editor: M. F. El-Amin

Copyright © 2012 Ming Wei et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Understanding platoon dispersion is critical for the coordination of traffic signal control in an urban traffic network. Assuming that platoon speed follows a truncated normal distribution, ranging from minimum speed to maximum speed, this paper develops a piecewise density function that describes platoon dispersion characteristics as the platoon moves from an upstream to a downstream intersection. Based on this density function, the expected number of cars in the platoon that pass the downstream intersection, and the expected number of cars in the platoon that do not pass the downstream point are calculated. To facilitate coordination in a traffic signal control system, dispersion models for the front and the rear of the platoon are also derived. Finally, a numeric computation for the coordination of successive signals is presented to illustrate the validity of the proposed model.