Platoon dispersion depends on friction. The authors hypothesise that this friction can be external and internal and that the internal friction depends on traffic density and volume. Platoon dispersion should consequently be influenced by traffic density and volume. This hypothetical relationship was confirmed by limited field observations and simulations. Platoon dispersion increases with increasing volume up to a maximum value, which is observed at lower volumes than capacity. Dispersion decreases with further increasing volume and becomes nearly zero at volumes near capacity. If further studies confirm the observed relationship, platoon dispersion could be calculated directly from densities or volumes and travel times, applied to Robertson's model on a link by link basis, thus improving the results of traffic signal co-ordination models.
Abstract