A Study in Creating Computational
Models of Traffic
Madeleine Pitsch 2005
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Street2.myArea 
Street1.myArea
World.world
World.land Graphic Portrayal
The goal of my project is to make an accurate simulation of traffic in an multi-lane intersection world that will be easily mutable for work in studies on the effects of construction work and accidents on traffic flow.
Traffic Simulations are used in a variety of ways. One of the most prominent and original uses was to use traffic simulations to evaluate alternate treatments. Since engineers were in control of all the variables, they could evaluate such things as signal control strategies, and speed limit management. Traffic simulations are often used to test new designs.
Because roadwork is so expensive, traffic simulations can help quantify the improvement of traffic flow with different geometric arrangements. Even more so, traffic simulations can also be an element of the design process as well. Traffic simulations are also used to test traffic center personal and can also be used to recreate a traffic accident and then
design a safer environment in response to that accident. 
Simulations describe a non-static environment in a statistical or pictorial way. They can be used whenever there is a system undergoing mathematical changes over a long period of time or there is a need to view an animation of the system to understand what is causing the final results. They are also approached when the mathematical equation can not accurately factor in all the agents of a system. Traffic simulations are used
to support optimization models, and new theories in management. They are
an efficient way to see understand calculated data particularly if the simulation creates an animation output. A certain approach should be taken towards a building a traffic
simulation. The first step is to define the problem and the model objectives. A builder must now what is the primary focus of his simulation so the appropriate model choices can be made to make the most efficient model for that purpose. The builder must now what data the simulation should output.
The next step is to then, using the previously found data, to define the situation the model is evaluating. The builder must understand the major components, and what are the major interactions of those components. He must as well identify the information that needs to be acquired. The third step is the most complicated and is where the actual modeling
occurs. The complexity of the model must be established to then identify which of the three classifications (macroscopic, mesoscopic, microscopic) will be used. Next is determine what will be the major functions of all of the components of the models and how the data will flow through the components. For that to be efficient, an appropriate hierarchy must be chosen as well. The modeling language must be chosen and all the logic in the program must be documented. The final point is the hardest which then
the actual coding of the program followed soon after by debugging.
After the model has been created, the model must then be tested with input
data and then followed up by acquizitionof output data. The model must be
validated and evaluated on pre-specified criteria relating to the actual
purpose of the model.
WorldWithUI
Car
Intersection Road
World
Lane(abstract)
At the end of this project, I should have a full-working animated traffic simulation with intersections and some multi-lane highways to aptly demonstrate how obstructions to the traffic flow cause decreasing amounts of flow. If well done, it will be aptly able to predict the traffic conditions created by accidents anywhere in the world as well as show normal day to day traffic. Construction road work is prevalent in most metropolitan areas and with every year more data is gathered to help decrease the effects of construction road work on traffic. Day to day traffic data can be used to help understand the problems in
some road networks and help tofind solutions to bottleneck areas.
A certain approach should be taken towards a building a traffic simulation. The first step is to define the problem and the model objectives. A builder must now what is the primary focus of his simulation so the appropriate model choices can be made to make the most efficient model for that purpose. The builder must now what data the simulation
should output. The next step is to then, using the previously found data, to define the
situation the model is evaluating. The builder must understand the major
components, and what are the major interactions of those components. He
must as well identify the information that needs to be acquired.
The third step is the most complicated and is where the actual modeling
occurs. The complexity of the model must be established to then identify
which of the three classifications (macroscopic, mesoscopic, microscopic)
will be used. Next is determine what will be the major functions of all of
the components of the models and how the data will flow through the
components. For that to be efficient, an appropriate hierarchy must be
chosen as well. The modeling language must be chosen and all the logic in
the program must be documented. The final point is the hardest which then
the actual coding of the program followed soon after by debugging.
After the model has been created, the model must then be tested with input
data and then followed up by acquizitionof output data. The model must be
validated and evaluated on pre-specified criteria relating to the actual
purpose of the model.

My approach to this project has always to work systematically each time adding a more complex idea. I will first work on programming single lane interaction followed by single lane intersection interaction. Once those two phases have been done I
will work to then make multiple lane interaction and multiple lane intersection interaction. Using these building blocks I can then make a world to then test
certain traffic principles. I particularly interested in the affects of traffic blockage or construction on a system.
Traffic simulation is a fairly complex computational model because of the many interactions between the agents and the world plus the duality of the agents
themselves. There has been much to study in approaching and understanding traffic simulations and why they are useful tools.
Animation displays are one of the best ways to analyze whether or not the model is an accurate representation of a traffic simulation. The analysis has to be through,
but can help identify cause-effect relationships and anomalous results. Particular cause-effect relationships to look out for are where congestion starts and is it
where consistent traffic jams start or only so often. Anomalous results (when traffic congestion starts in an illogical point) should be observed until they can be
pinpointed to a particular behavioral or model deficiency.
The organization of the program was the hardest part to create. Because of the constraints of the sparse grid, the main class world has two major area data members: World, Land. World is the sparse grid with actual street objects in it. It also
has token car objects which are used to create the graphic display. Each street has its own data area of the its length were the actual cars are located
whose location corresponds with the world location of the token. The world's other data member, land, is a double grid with the graphic layout of the
streets, streets represented by 1, nothing by 0. The actual graphical portrayal is created using the land data member and the token locations in World.world.