The name is absent

CHAPTER 2. OPTIMIZATIONANDADAPTATIONOFTRAFFICLIGHTS6

Self organizing traffic lights by Carlos Gershenson

Carlos Gershenson presents three self-organizing control methods: sotl-request,
sotl-phase and sotl-platoon. Marching control and Optim control are non adaptive
methods and are used to compare those self-organizing control methods. The
definitions of the controllers are given below, which are quoted from the paper of
Carlos Gershenson [Ger05]. Those definitions are for one direction lanes. The
realistic simulation has two-direction roads for scenario 1 and 2.

Marching Control

All traffic lights “march in step”: all green lights are either south-
bound or eastbound, synchronized in time. Intersections have a phase
φ_i, which counts time steps. φ_i is reset to zero when the phase reaches
a period value p. When φ_i = 0, red lights turn green, and yellow
lights turn red. Green lights turn yellow one time step earlier, that is,
when φ = p — 1. A full cycle of an intersection consists of 2p time
steps. “Marching”intersections are such that φ_i = φ_j, ∀i,j.

Optim control

This method is implemented trying to set phases φ_i of traffic lights in
such a way that, as soon as a red light turns green, a car stopped by
this would find the following traffic lights green. In other words, we
obtain a fixed solution so that green waves flow to the southeast. This
green wave method is very popular for avenues that have preference
over crossing streets.

Sotl-request control

All three self-organizing control methods use a similar principle: traf-
fic lights keep a counter κi which is set to zero when the light turns
red and then incremented at each time step by the number of cars ap-
proaching only the red light independently of the status or speed of

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