Chapter 5
Simulation results
The proposed self-organizing traffic light controllers are tested by traffic simula-
tions. Two other traffic light controllers, optim (green wave) and marching, will
be used to compare those self-organizing controllers with non self-organizing con-
trollers.
All simulations are done five times and the average values of the simulation
results are given in the following sections. The resulting data consists of ATWT
and TWQL. Those values are taken after 3600 cycles (representing 1 hour) of
simulation. The ATWT is the average total waiting time of the road users in the
simulation. The edge-nodes are the borders of the scenario. Those edge-nodes
spawn road users into the scenario. When the traffic density is high and the road
connected to the edge-node is full, spawned road users cannot enter and those road
users are queued in the edge-node. The TWQL (total waiting queue length) is the
sum of all queued road users in the edge-nodes.
Every map has its spawn and destination frequencies. Those frequencies de-
fine how many road users an edge-node will produce, and where those road users
will go. For every edge-node there is one spawn frequency and n - 1 destination
frequencies (one for every possible destination). A spawn frequency is a value
between zero and one. If it is zero, no vehicles will be spawned. If it is one, the
edge-node will spawn a vehicle at every cycle.
The first scenario is a simple road map with 2 junctions and traffic in all di-
rections. The second scenario contains 5 junctions with traffic in all directions.
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