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Pedestrian Simulation for Urban Traffic Scenarios

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1224m MAINS<br />

²<br />

Multimodal<br />

Innercity<br />

<strong>Simulation</strong><br />

IM<br />

Multimodale Innerstädtische Straßenverkehrssimulation<br />

Figure 5. Map extract of the city Hanau, Germany with an accumulated length of roads of 548km, amount of EIs: 5,400 and<br />

amount of NIs: 3,878.<br />

Figure 8. Change of aggressiveness over time.<br />

a basic AF of about +0.4, leading to a behavior which is overcautious.<br />

From point a to c, the pedestrian has to wait <strong>for</strong> a<br />

sufficient gap in order to cross a road. His aggressiveness increases<br />

with step size 0.1 · s −1 . This value is not documented<br />

in literature but shows the basic principle. Finally, the crossing<br />

action takes place and the aggressiveness recovers.<br />

5.3 <strong>Pedestrian</strong> Crossings<br />

<strong>Pedestrian</strong> crossings can be analyzed with help of the well<br />

known density (ρ) - mean velocity (v) diagram. The traffic<br />

density of a pedestrian way is calculated as stated in equation<br />

9.<br />

ρ = #pedestrians<br />

C<br />

(9)<br />

The capacity of a pedestrian way is C = w·l ·(0.457) −1 . This<br />

definition is according to [1] which defines cells with width<br />

of 0.457m being fully occupied by one pedestrian.<br />

The ρ - v relation has to be divided according to the amount<br />

of pedestrians walking in both directions, because different<br />

compositions lead to different ρ - v relations.<br />

In order to analyze the relation, a single pedestrian way<br />

object is used <strong>for</strong> simulation. It has five lanes and a length of<br />

l = 10 · 0.457m and thus leads to a realistic pedestrian crossing.<br />

The amount of pedestrians is set to one <strong>for</strong> the first run<br />

and is then increased by 1, until 75 runs have been made.<br />

The results represent average values of 10 replications <strong>for</strong><br />

each setting. After a settlement phase of 500 iterations, 5,000<br />

iterations are used <strong>for</strong> measurements of the average velocity<br />

v of all pedestrians on the way. This procedure is per<strong>for</strong>med<br />

<strong>for</strong> different compositions of directions of travel with<br />

50%,60%,··· ,100% pedestrians walking into one direction<br />

and the rest into the other direction. Figure 9 shows the resulting<br />

diagram.<br />

As can be seen, the maximum density differs in relation to<br />

the composition of walking directions. This results from the<br />

queuing process of the algorithm, shown in figure 4. <strong>Pedestrian</strong>s<br />

walk faster, when there is no opposing traffic and there<strong>for</strong>e<br />

the distances between two subsequent pedestrians increase.<br />

Figure 9 shows that the more balanced the distribution of<br />

walking directions is, the higher the maximum values of ρ<br />

get and the lower the mean velocity v. This is in line with the<br />

results presented in [1] with the difference that only realistic<br />

densities <strong>for</strong> urban traffic road crossings are generated.<br />

It seems to be likely that only parts of the shown figure 9<br />

occur in urban traffic. Hence, another experiment comes back

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