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Traffic Simulator

traffic-simulation.de

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Re: Traffic Simulator

#101

Post by sumtechguy »

waiseristy wrote: post #76
albertzeyer wrote: post #51

Cities Skylines is very nice for such traffic simulations. https://www.youtube.com/watch?v=yITr127KZtQ ( https://news.ycombinator.com/item?id=17182008 ) ( https://www.reddit.com/r/CitiesSkylines/comments/7h6zr0/traf... ) https://www.youtube.com/c/BiffaPlaysIndie/search?query=lane+... This is frequently posted here on HN. E.g. https://news.ycombinator.com/item?id=25632642 .

Unfortunately CS suffers from many "dumb computer tricks". The pathing algorithm is open loop, often causing huge 1 lane jams even though it would be more efficient for through traffic to use other less congested lanes. You end up needing to create crazy unrealistic spaghetti interchanges in order to trick the AI into behaving

Having watched way too many Biffa vids. The way to fix that is to create/force dedicated turning lanes. There is a plugin that lets you manage it. It should be built in. If you do not have the plugin sometimes you can fix it by changing the number of lanes on both sides of an interchange (what biffa calls lane mathematics). Basically if you have 3 lanes merging into 3 you need a 6 lane on the other side. If you have 6 and 3 dumping off you need 3 for both exits. That does not fix 4 way intersections though and usually you need the plugins to fix that.

Re: Traffic Simulator

#102

Post by bstar77 »

albertzeyer wrote: post #51

Cities Skylines is very nice for such traffic simulations. https://www.youtube.com/watch?v=yITr127KZtQ ( https://news.ycombinator.com/item?id=17182008 ) ( https://www.reddit.com/r/CitiesSkylines/comments/7h6zr0/traf... ) https://www.youtube.com/c/BiffaPlaysIndie/search?query=lane+... This is frequently posted here on HN. E.g. https://news.ycombinator.com/item?id=25632642 .

City Skylines traffic simulation is mediocre at best. This project is extremely impressive. I sat and watched the traffic simulation for 15 minutes before I realized it.

Re: Traffic Simulator

#103

Post by imaginenore »

matkoniecz wrote: post #95
albertzeyer wrote: post #51

Cities Skylines is very nice for such traffic simulations. https://www.youtube.com/watch?v=yITr127KZtQ ( https://news.ycombinator.com/item?id=17182008 ) ( https://www.reddit.com/r/CitiesSkylines/comments/7h6zr0/traf... ) https://www.youtube.com/c/BiffaPlaysIndie/search?query=lane+... This is frequently posted here on HN. E.g. https://news.ycombinator.com/item?id=25632642 .

A/B Street is much, much more ambitious as far as traffic simulation goes, but still in progress. https://github.com/dabreegster/abstreet#ab-street If someone is looking for interesting Rust project to contribute (also as a beginner) I really recommend it. Author is great, friendly to PRs (what includes PRs made be programmers with no Rust experience).

That looks really cool! I hope they finish it.

Re: Traffic Simulator

#104

Post by TheGallopedHigh »

screye wrote: post #77
sandworm101 wrote: post #56

I love these little simulators because while they purport to show that slower more polite driving is more efficient, more often than not they show the exact opposite. Want to shove the most cars through per hour? Remove the speed limit. Accelerate and brake like every intersection is a drag race. Leave absolutely no distance between cars. And dump any notion of polite lane changes. NASCAR was right: Minimize unused p…

One solution might be to characterize individual drivers (agents) by running an RL experiment that mimics the interactions of individual car drivers. If the reward function is made to compare traffic patterns of the simulation vs real life, then eventually the RL model (a combination of agents) should converge to how humans drive. So you would have various transition probabilities of a car driver moving from an atten…

These type of models are done to death in traffic and other social models. Just look up “agent based modeling” and read to your heart’s content

Re: Traffic Simulator

#105

Post by analog31 »

xixixao wrote: post #44

Needs an American mode where people don’t know they should stick to the right-most lane, unless passing.

To simulate my neighborhood, it needs some parked cars and trees that appear out of nowhere.

Re: Traffic Simulator

#106

Post by bonestamp2 »

vbtemp wrote: post #16

Things like this are cool. What I would be curious to see though, rather than setting global parameters (i.e., politeness), would be to have each agent have its own politeness score (as well as other attributes). Models like the one linked to here work as if each agent is a particle, rather than autonomous decision-maker adapting to their circumstances locked in long-term, iterated games with other anonymous drivers.…

It would be cool to study things like politeness, top speed, acceleration, etc in different cities and then create traffic profiles that represent these cities and see what kind of tweaks can improve each one.

Re: Traffic Simulator

#107

Post by mongol »

I would like to use a driving simulator to learn how to drive on the left side. Is there something like that? Good if I would rent a car on Ireland.

Re: Traffic Simulator

#108

Post by ravi-delia »

jedberg wrote: post #63
sandworm101 wrote: post #56

I love these little simulators because while they purport to show that slower more polite driving is more efficient, more often than not they show the exact opposite. Want to shove the most cars through per hour? Remove the speed limit. Accelerate and brake like every intersection is a drag race. Leave absolutely no distance between cars. And dump any notion of polite lane changes. NASCAR was right: Minimize unused p…

That's because these simulations don't include inattentive drivers. They assume everyone behaves ideally. Normally all those things you said would result in accidents. If the simulators randomly added delays for cars braking or starting up, and then kept a death count, it would be more accurate...

Hell screw the death count, just a graph of average commuting time becoming unbounded would be enough to get people on board.

Re: Traffic Simulator

#109

Post by throwaway0a5e »

scatters wrote: post #75
throwaway0a5e wrote: post #54

Earlier quoted context omitted.

"Induced demand" is just a backhanded way of complaining that more people can be served by expansion of a particular piece of infrastructure that you don't like. Nobody ever complains about induced demand on the subway from more frequent service causing more people to decide that's the best option for them. Rush hour is like pouring a 5gal bucket into a sink. You can't reasonably handle that all at once will have som…

More frequent service on the subway doesn't require vast amounts of land to be removed from productive activity. At most it might require a small expansion of stabling facilities for extra carriages and engines. Induced demand means that when you make the drain pipe bigger, the bucket gets bigger as well, so the sink gets even more full. This is not sustainable.

Why is more utilization a problem? It means more people are being served by infrastructure. Imagine complaining that more people are going to parks because the city turned a bunch of vacant lots into parks.

In the case of things like roads, rails and bus stops more utilization means more economic activity which is a good thing.

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