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A/B Street: A simulation game to fix Seattle's traffic

abstreet.org

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Re: A/B Street: A simulation game to fix Seattle's traffic

#51

Post by xxpor »

WalterBright wrote: post #35

Fixing the traffic lights would go a long way towards improving traffic flow in Seattle. How much time do you spend sitting at a red light when there's no cross traffic? How often are you and the 5 cars behind you abruptly stopped to let one cross traffic car through? Lots of traffic lights already have cameras on them. Hook 'em up to an AI and a goal of maximizing throughput.

This sounds simple but it really isn't.

First, the vast majority of signals aren't networked, they're on simple timers. And you can't just put them on the internet for hopefully obvious reasons.

Second, there's a bit of a butterfly effect. Change one thing and the whole system reacts in sometimes unpredictable ways.

Third, you need to account for pedestrians too. There's ADA requirements around how long signals are green for based on the width of the road.

Fourth, you need to account for pedestrian load. There's no cameras trained on the areas where pedestrians gather. If you're going to say they just need to press the button, no:

https://cal.streetsblog.org/2020/04/01/stop-touching-pedestr...

Basically, it's really not that simple.

Re: A/B Street: A simulation game to fix Seattle's traffic

#52

Post by dabreegster »

jakecopp wrote: post #43

Woah, the data comes from OpenStreetMap! Is it possible to create a map with one click for a new city? I read through https://github.com/dabreegster/abstreet/blob/master/docs/art... but I can't tell if this must be manually followed.

https://github.com/dabreegster/abstreet/blob/master/docs/new...

Not quite one-click, but you can try the one-shot importer. You'll probably hit some issues; I have strict assertions to prevent regressions in Seattle. Please file a bug if you can't get a new place to work.

Re: A/B Street: A simulation game to fix Seattle's traffic

#53

Post by jcims »

linuxftw wrote: post #26

The problem is there's only so much room for automobiles in a city. The more you decrease traffic, the more you'll induce demand to fill those improved traffic flow patterns. The more infrastructure that is built downtown, the more people want to be downtown.

Now you've got a cool simulator to prove it!

Re: A/B Street: A simulation game to fix Seattle's traffic

#54

Post by pugworthy »

WalterBright wrote: post #35

Fixing the traffic lights would go a long way towards improving traffic flow in Seattle. How much time do you spend sitting at a red light when there's no cross traffic? How often are you and the 5 cars behind you abruptly stopped to let one cross traffic car through? Lots of traffic lights already have cameras on them. Hook 'em up to an AI and a goal of maximizing throughput.

As simple as this sounds, there are ramifications. It might make sense for YOU at that light at the time, but does it make sense for the greater good of flow?

Off hand, I'd say lights are often timed such that once you get one green you get a lot of greens, then you're asking for more stop and go traffic simply because someone showed up and threw off the sequence.

Take away that and you gain some benefits, but you also lose in other areas.

Not an easy problem.

Re: A/B Street: A simulation game to fix Seattle's traffic

#55

Post by dabreegster »

aunty_helen wrote: post #42
dabreegster wrote: post #18

Earlier quoted context omitted.

https://github.com/dabreegster/abstreet/blob/master/docs/new... Biggest barrier is lack of trip demand data. If you come up with how many people leave from building1 to building2 at time T using some mode of transport, then this can work.

Hey this is something I've been working on as a side project for the last 2 years. Using traffic cameras to detect the flows through intersections with the goal of providing better stats to governments and city planners. Hopefully I can have the poc going in the next month. A city wide integration with something like AB street would be really cool and was phase 2 for this project. Phase 3 being an optimised citywide…

Whoa, this would be awesome! Strongly consider publishing open datasets. :) Could you talk at all about how it works, or what privacy issues you've dealt with?

Re: A/B Street: A simulation game to fix Seattle's traffic

#56

Post by pugworthy »

Adding a options for rethinking current systems would be nice.

For example, autonomous vehicles would be interesting. You potentially don't need intersection control with all autonomous traffic. Or what is the benefit of certain streets or lanes being designated autonomous only?

And what is the impact of education? Is there a way to change behavior that's cheaper than changing a street for example? You can change the street, but you can also change how people use the street.

Re: A/B Street: A simulation game to fix Seattle's traffic

#57

Post by spyder »

dabreegster wrote: post #2

Hi, author here. Previously posted to HN ( https://news.ycombinator.com/item?id=21763636 ). I just released alpha -- check out this cheesy trailer ( https://www.youtube.com/watch?v=LxPD4n_1-LU ). Happy to answer questions! And if you're serious about running this in your city, the importing process has improved greatly since December, so get in touch.

Reminds me of the Citybound game in (slow :( ) development by basically one guy and also written in Rust:

https://aeplay.org/citybound

He demoed his actor system with 100 000 cars in the middle of this talk: https://www.youtube.com/watch?v=qr9GTTST_Dk

Maybe you guys should team up :) (if not already...)

Re: A/B Street: A simulation game to fix Seattle's traffic

#58

Post by totetsu »

rzzzt wrote: post #31
com2kid wrote: post #21

Earlier quoted context omitted.

Do any of the mods give the simulated people real commutes? I gave up after I made a city with a full subway system and zoned areas and watched as the simulated citizens left home, went to work, and then went to another random home at night. It completely ruined my fancy subway system's timetable. :(

A relevant movie from the USSR comes to mind (which was also discussed recently): https://en.wikipedia.org/wiki/The_Irony_of_Fate

Oh. I've seen that.

Re: A/B Street: A simulation game to fix Seattle's traffic

#59

Post by MikeTheGreat »

rzzzt wrote: post #31
com2kid wrote: post #21

Earlier quoted context omitted.

Do any of the mods give the simulated people real commutes? I gave up after I made a city with a full subway system and zoned areas and watched as the simulated citizens left home, went to work, and then went to another random home at night. It completely ruined my fancy subway system's timetable. :(

A relevant movie from the USSR comes to mind (which was also discussed recently): https://en.wikipedia.org/wiki/The_Irony_of_Fate

Another somewhat relevant film: :)

https://en.wikipedia.org/wiki/Dark_City_(1998_film)

Re: A/B Street: A simulation game to fix Seattle's traffic

#60

Post by runarberg »

pugworthy wrote: post #56

Adding a options for rethinking current systems would be nice. For example, autonomous vehicles would be interesting. You potentially don't need intersection control with all autonomous traffic. Or what is the benefit of certain streets or lanes being designated autonomous only? And what is the impact of education? Is there a way to change behavior that's cheaper than changing a street for example? You can change the…

> You potentially don't need intersection control with all autonomous traffic

I thought this myth had been widely debunked. In a world where every commuter drives a 100% autonomous car, you still have hobbyists driving old vintage cars, cyclists riding non-autonomous bikes, pedestrians, birds, runaway shopping carts, etc. disrupting the flow of traffic. Without traffic control you make the intersection in-crossible for a significant subset of the traffic.

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