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Traffic Simulator

traffic-simulation.de

111–120 of 143 posts

Re: Traffic Simulator

#111
Reminded of Java simulations that show yielding control of your vehicle 100 yards before a 4-way "smart" intersection can allow the central command to get every car through safely without adjusting anyone's speed more than 5 MPH.

Wish I could find it again.

Re: Traffic Simulator

#112

Earlier quoted context omitted.

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…

I have tried this method, and it does indeed work (TM:PE is the mod I think you are talking about). But at some point the sims have to change lanes to get into the correct one to turn, unfortunately they wait until the last possible moment to switch, causing huge traffic issues. On top of that the sims still prefer a single lane even if you do the lane mathematics. A 6 lane freeway, splitting to a 2 lane and 4 lane doesn't help when the sims still insist on using 1 of those 2 and 4 lanes.

Re: Traffic Simulator

#113
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.…

> I'm really curious why some places...

Based on my experience of living in different countries, differences in behaviour and car culture are often underlined by hidden aspects of legislation which support those differences. I'm thinking more in terms of who is liable in the event of a crash, rather than the actual traffic rules.

>Some places the drivers are so polite to the point it really makes things dangerous

I think the danger you are talking about generally comes from the lack of anticipation and lack of meeting expectations, rather than the politeness.

If you shock a driver's expectations, that will at least appear dangerous, because they have to consciously react (or crash). A Bangkok-style driver in DC is dangerous, just as a DC-style driver in Bangkok is the dangerous one.

Re: Traffic Simulator

#114
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.…

> In DC, people carefully adhere to red lights, stop signs, pedestrians, etc but will go far, far out of their way to block you from changing lanes once they see your turn signal go on.

The last part, yes, but the first half has very much not been my experience here in DC. I usually see at least one driver blow a stop sign, red light, or one-way street before I make it 2 blocks from my house. The other thing I found amazing is that it's totally normed that you can just park in the traffic lane whenever you want — not just FedEx/Amazon but I've seen people park downtown at rush hour, get their dry cleaning, and get back in their car as if it was normal.

I think the main cause here is that we have a bunch of poorly-trained commuters from suburbs where they're used to high speed limits and wide, less used roads but the traffic means they're lucky to average 5mph on their commute into the city and a certain fraction of people cut any corner they can because they think they're owed a higher average speed. They're “running late” every day because they don't want to admit that their “30 minute commute” is off by a factor of 2-3. I'm curious whether the pandemic will lead to people trying to stay at 100% telework after realizing how much better life is without spending a couple hours a day stuck in traffic.

Re: Traffic Simulator

#116
post #81
post #27

Earlier quoted context omitted.

Places where I've seen it, people who have the right of way take that to mean they get to play "traffic cop". E.g., at a 4-way stop the "extra polite" person who gets there first, instead of going through the intersection first, waits and waves the person who does not have the right of way to go through first, which makes that person (and everyone else) confused, and then causes a lot of slowdown, frustration, etc. O…

this has always bothered me. if you have the right of way, and you do not take the right of way, in most cases you are effectively disobeying traffic rules and disrupting the flow of traffic.

In rural areas where this is common there isn't traffic. Thus the politeness doesn't cost you anything. Also in those rural areas it is somewhat common for someone with the right away to have a reason to drive much slower than the speed limit and so giving up your right away makes things better for everyone - the other person doesn't have to try to pass you latter.

When there is traffic you giving up the right away is impolite to the person behind you and shouldn't be done. unless traffic is so heavy that you won't be able to move, and so you should give you your right away to someone who can go.

Re: Traffic Simulator

#117
post #85

Earlier quoted context omitted.

Putting more people through per stoplight doesn't really change much. You just get more people at the next stop light. The light is by far the limiting factor, not the drivers. That's why polite driving actually helps, because you get less people blocking each other and less mishaps, the things that actually slow everything down.

You've never been stopped at a light where the queue was many multiples of the number of cars that could get through in one cycle?

Or more infuriating, when you want to make a left turn, but the dedicated lane for that is unreachable until the queue in front of you moves through the intersection. And some inattentive driver ahead misses the light and leaves you with an opening that is exactly 1 foot narrower than your car.

Re: Traffic Simulator

#118

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 .

I don't think traffic in Cities Skylines can count as "nice". I quit playing CS because I spent 80% of the time fixing the traffic. It gets exponentially harder as your city gets bigger. I found myself using extensions to designate lane change rules, set precise traffic light time periods, etc. It was time consuming and the fun was lost.

The cars in the demo seem much much smarter.

EDIT: typos.

Re: Traffic Simulator

#120
about the one lane backups, one method that i employ are 3 lane roads, all only lanes and by use of TM:PE, say do not switch lanes for 5 points before intersection, forcing traffic to use all lanes.
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