Full-scale Traffic Simulation of Wuppertal
(pictures on this pages can be seen in large by clicking upon them)
The simulation yet to be done consists of five parts, which closely resemble
the classical four-stage algorithm of the traffic-engineering:
Traffic generation
Here we try to calculate the time-dependent O/D-matrix for Wuppertal,
i.e. the demand for transportation as a function of time.
This
movie (12.2 MB AVI) shows the time-dependence of the total in-
and outgoing demand for transportation.
In the next step, (after splitting the public transport part, which
is handled separately,) this O/D-matrix is converted into the routes
of the individual cars by means of
Dynamic Traffic Assignment (DTA)
The DTA-algorithm takes the O/D-matrix and computes a set of routes
from it by using a so-called simulation-based approach (day-to-day
simulation). This means, that a pretty fast microsimulation model is
used (able to calculate 108 cars in real-time), which
resolves the road-network on a link-basis. The routes are then input
into an
Microscopic Simulation of Traffic
which is used to resolve the traffic-load on a high spatial and
temporal resolution, but can compute only 106 cars in real-time. A
small example of such an simulation, which may give a first
impression, can be be gained with the following
movie, encoded in MPEG (12.4 MB), which
unfortunately is rather large. Please note, that the cars are driving
randomly in this network, since the dynamic O/D-matrices and the
sampling of traffic counts is not yet finished.
Finally, the traffic-load computed in this way can be
used to calculate the emissions, that are finally put into models
for the
Simulation of Transmission & Transport of Pollutants
Models of this kind are able to model the transformation of emissions to immissions, that are finally used to understand the
Impact on Humans & Environment
However, there are other effects of traffic on humans and environment than
immissions alone, e.g. a very strong effect stems from the separation effect
that roads with high traffic load impose on the inhabitants near the road.
Last modified: Tue Jun 29 17:04:41 MET DST 2004
(PW)