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Traffic Simulator

traffic-simulation.de

1–10 of 143 posts

Re: Traffic Simulator

#2
Regardless of how I change the map layout, traffic in/out flow or truck/car ratio I seem to get the best results when I crank accel, speed and right bias for trucks to the max and lane-change threshold and following distance to the minimum.

Which makes sense since those are basically the ideal conditions for reducing the number of obstructions low speed (merging, exiting, trucks on grade) traffic poses to higher speed traffic and reduces the effective road area of the obstruction.

Re: Traffic Simulator

#4
Perhaps these questions are appropriate for this post.

I'm beginning to delve into this space and I've not managed to get any satisfactory answers to these questions, despite my month(s) long search.

1) How does one build a traffic (i.e state-space system), forgetting the visualization aspect of things ? Just generating sparse matrices, and adding elements to interact (add/subtract) from these matrices would be a great start! Any way to do this in a compiled language ?

2) Are there any libraries out there that help you simulate traffic in an existing network of roads, extracted from OpenStreetMaps perhaps?

Re: Traffic Simulator

#5
What is the source of the logic for these mechanics? Meaning, how did you model the results of these inputs? Traffic phenomena is really interesting to me. This is a great way to present these inputs and visually present the outcomes.

Re: Traffic Simulator

#6
Love these kind of micro simulations! They really help to discover non intuitive behaviour of complex systems just by playing around. Great job!

Re: Traffic Simulator

#7
post #5

What is the source of the logic for these mechanics? Meaning, how did you model the results of these inputs? Traffic phenomena is really interesting to me. This is a great way to present these inputs and visually present the outcomes.

To model these types of processes people usually use stochastic processes (https://en.wikipedia.org/wiki/Stochastic_process). I don't know what the author used, but seems inaccurate.

Re: Traffic Simulator

#8

Regardless of how I change the map layout, traffic in/out flow or truck/car ratio I seem to get the best results when I crank accel, speed and right bias for trucks to the max and lane-change threshold and following distance to the minimum. Which makes sense since those are basically the ideal conditions for reducing the number of obstructions low speed (merging, exiting, trucks on grade) traffic poses to higher spee…

You can almost always fix the traffic by maxing out acceleration. Sadly, this vindicates my real world aggressive driving behavior.

Re: Traffic Simulator

#9

Perhaps these questions are appropriate for this post. I'm beginning to delve into this space and I've not managed to get any satisfactory answers to these questions, despite my month(s) long search. 1) How does one build a traffic (i.e state-space system), forgetting the visualization aspect of things ? Just generating sparse matrices, and adding elements to interact (add/subtract) from these matrices would be a gre…

This doesn't exactly answer your question, but what I settled on during my dissertation (granted, that was a few years ago now) was SUMO: https://www.eclipse.org/sumo/

IIRC you could import maps from from open street map, but I'm not sure if it has a "headless" mode, without all the visualisation.

Re: Traffic Simulator

#10
post #5

What is the source of the logic for these mechanics? Meaning, how did you model the results of these inputs? Traffic phenomena is really interesting to me. This is a great way to present these inputs and visually present the outcomes.

The author used the "intelligent driver model" (IDM): https://traffic-simulation.de/info/info_IDM.html

It's a system of ODEs that describes the dynamics of each driver. So the inputs are: the parameters of the model and the inflow of cars in the section of road

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