6 ms·

Now someone needs to invent a traffic light system that uses data collected by sensors and cameras to dynamically adjust traffic lights to improve traffic flow.

by Osiris 10y ago

Now someone needs to invent a traffic light system that uses data collected by sensors and cameras to dynamically adjust traffic lights to improve traffic flow. My brother and I envisioned this idea a decade ago. Imagine a system that can use deep learning techniques to automatically manage traffic to optimize travel times.

flukus 10y ago
I wonder if this is desirable or if it's a case of predictability being better than efficiency. It might be better to know it takes 30 minutes to get somewhere than to vary from 20 to 40 minutes depending on what mood the AI is in.
superuser2 10y ago
This has been done for quite some time, and it's unclear what value deep learning would add beyond the arithmetic we've used for a while. https://en.wikipedia.org/wiki/Signal_timing https://en.wikipedia.org/wiki/Signal_timing Major cities have Transit Operations Centers or similar where engineers watch road camera and sensor data (as well as local news and other sources of information) and direct traffic lights, gates, police, etc. to keep things moving. There was actually a controversy in London when this control room manipulated traffic lights so the International Olympic Committee officials evaluating London would always hit green lights, and perceive the traffic as better than it actually was. This may be less apparent in some areas because it is actually done with the opposite intention: to slow things down. If you seem to be hitting every red light, it is probably because the local government decided to install a Traffic Calming program there in the interest of safety / fewer complaints from the neighbors.
- EGreg 10y ago
  If I was running for mayor of NYC I would focus my campaign heavily on cleaning up the traffic: 1) Negotiate with all those stores to move deliveries to night-time. So more parking opens up and they don't clog the streets. Any losses from eg tax breaks would be more than offset by the increased productivity. 2) Reward companies that allow employees to work from home one day a week, or that organize carpooling for employees. Install wifi in city subway CARS and run a campaign targeting companies letting them know their employees are more productive on the train with both hands free than stuck in traffic. 3) Get an official app for the city to let drivers know when parking spots open up. 30% of traffic in the city is cars circling around looking for parking. Charge a monthly fee for the app, and allow paying for parking via the app. However, I probably wouldn't want to allow people to renew their parking past 2 hours so the city could still make revenue from people who overstay. Also prevents people hogging the spots. 4) Apply the results of traffic research to tunnels and bridges which have heavy delays. Make all the traffic lights leading up to the tunnel reward 20mph driving, while at the tunnel exits it would reward 30mph driving. It's easy to force traffic to preset speeds like this using traffic lights, and you could do this for several blocks leading up to and away from the tunnels. In short - less frustration, less pollution, less circling around, people get to where they want faster, make more money and city is better off.
  - superuser2 10y ago
    Street parking is just a terrible experience all around. I'd prefer to see most street parking eliminated in favor of dedicated rights-of-way for bikes, buses, taxis, rideshare, etc. If you want to have a car, you have to live somewhere that has an alley/garage space for you. If you want your business to be usable by drivers, have a parking lot or do a parking validation deal with a nearby garage. I think the SpotHero/ParkWhiz model is very cool, would love to see it turn into a real-time auction with very precise competitive demand-based pricing. "Parking is surging right now, consider taking UberPool for $x less." I already don't drive anywhere in Chicago unless I know there's an adequately sized parking lot, or I've booked reasonably priced parking ahead of time. Seeing ahead of time that there is no reasonably priced parking generally makes me take the CTA, whereas otherwise I might have circled for a while before breaking down and paying $25.
    - finid 10y ago
      > If you want to have a car, you have to live somewhere that has an alley/garage space for you. You're obviously not referring to NYC.
      - Symbiote 10y ago
        Why not? That's the case in the centres of many European cities.
        finid 10y ago
        NYC is different. Most parking is street parking, or a paid garage parking, which can be expensive.
        Symbiote 10y ago
        > Most parking is street parking That's a decision the city has made, and the current state of much street-space in NYC. Copenhagen has made the opposite decision: space in the city centre is allocated to bicycle lanes and footpaths on many streets. I live on such a street. If I bought a car, I'd need to rent a parking space. London has an intermediate approach: resident parking on the street requires an expensive permit.
- Natsu 10y ago
  Yeah, but the funny thing about the all red timing that I've seen is that people can beat it by going faster than they should, which always struck me as wrong.
  - eximius 10y ago
    I do exactly this. :/
- WalterBright 10y ago
  > This has been done for quite some time, and it's unclear what value deep learning would add beyond the arithmetic we've used for a while. I've seen a lot of these claims, and they're easily debunked by driving through a city. The usual case is a platoon of 5 cars cruising down an arterial. A solitary car pulls up on a side street, and the light turns read for the arterial just in time to stop the platoon for the solitary car. A sensible algorithm would let the platoon pass first. There are endless scenarios of these, to the point where the light algorithm finds a local optima where it is completely out of phase with the traffic and causes maximum delay and minimum throughput. A relatively small amount of effort going into cameras and an adaptive system that minimizes a cost function would save billions of dollars in gas, time, and unneeded road widening.
  - Buttons840 10y ago
    There are two scenarios that inevitably get me thinking about smarter traffic lights. The first, is what you described, and the second is when I notice myself and a few others are sitting at a stop light while the intersection remains unused for 30 seconds.
  - gwbas1c 10y ago
    Santa Clara, CA trumps out "retime the traffic lights" every time they want to raise taxes. Biggest crock of B.S. I've seen in a ballot.
  - asynchronous13 10y ago
    > A sensible algorithm would let the platoon pass first. You're taking an example of a sub-optimal local solution and claiming that is proof that the global solution is sub-optimal. That does not follow. It could easily be, taking your example, that the platoon of 5 cars must stop at some future light, and the delay for 1 car is the smallest delay available for those cars. Therefore, stopping for the 1 car reduces the platoon's total travel time. As the driver, it's easy to think that was dumb because you'll never see the 15-car wait that was avoided by stopping early for 1 car. Essentially, you are claiming that a greedy algorithm for traffic would always find the globally optimal solution (which we know is not true).
gsmethells 10y ago
I think traffic lights are ripe for disruption.
- lukiebriner 10y ago
  You would think. However, even the current UK systems are nowhere near optimal. Crossings that block traffic for too long; Cycle crossings that stop for longer than pedestrian crossings; Lights that are at red even when there are no other cars. If councils are not motivated to optimize the current systems, they are unlikely to be interested in anything new and disruptive? There is also the pain of taking any new ideas through the approvals system, which I can only guess is both not easy and will be gamed by the larger companies.
  - 7952 10y ago
    Outside my house is a crossing that waits until a gap appears in traffic before letting the pedestrian cross. Usually, by the time this happens I have already crossed the road (because a gap has appeared!). Optimising "traffic flow" only seems to cause an obstruction for local pedestrians and cyclists. The only real purpose of a crossing is to restrict pedestrians so that excessive vehicle traffic can be accomadated. They should either prioritise pedestrians or reduce traffic.
ajdlinux 10y ago
You mean https://en.wikipedia.org/wiki/Adaptive_traffic_control https://en.wikipedia.org/wiki/Adaptive_traffic_control, which we've used in every major jurisdiction of Australia starting in the 1970s?
- deleted 10y ago
  [deleted]
- petepete 10y ago
  In the UK too. Here's an interesting look at how vehicle detection works https://www.linkedin.com/pulse/20141005200312-83983163-traffic-signals-part-6-vehicle-detection https://www.linkedin.com/pulse/20141005200312-83983163-traff...
column 10y ago
https://xkcd.com/277/ https://xkcd.com/277/

by Osiris 10y ago

flukus 10y ago

I wonder if this is desirable or if it's a case of predictability being better than efficiency. It might be better to know it takes 30 minutes to get somewhere than to vary from 20 to 40 minutes depending on what mood the AI is in.

superuser2 10y ago

This has been done for quite some time, and it's unclear what value deep learning would add beyond the arithmetic we've used for a while. https://en.wikipedia.org/wiki/Signal_timing https://en.wikipedia.org/wiki/Signal_timing Major cities have Transit Operations Centers or similar where engineers watch road camera and sensor data (as well as local news and other sources of information) and direct traffic lights, gates, police, etc. to keep things moving. There was actually a controversy in London when this control room manipulated traffic lights so the International Olympic Committee officials evaluating London would always hit green lights, and perceive the traffic as better than it actually was. This may be less apparent in some areas because it is actually done with the opposite intention: to slow things down. If you seem to be hitting every red light, it is probably because the local government decided to install a Traffic Calming program there in the interest of safety / fewer complaints from the neighbors.

EGreg 10y ago
If I was running for mayor of NYC I would focus my campaign heavily on cleaning up the traffic: 1) Negotiate with all those stores to move deliveries to night-time. So more parking opens up and they don't clog the streets. Any losses from eg tax breaks would be more than offset by the increased productivity. 2) Reward companies that allow employees to work from home one day a week, or that organize carpooling for employees. Install wifi in city subway CARS and run a campaign targeting companies letting them know their employees are more productive on the train with both hands free than stuck in traffic. 3) Get an official app for the city to let drivers know when parking spots open up. 30% of traffic in the city is cars circling around looking for parking. Charge a monthly fee for the app, and allow paying for parking via the app. However, I probably wouldn't want to allow people to renew their parking past 2 hours so the city could still make revenue from people who overstay. Also prevents people hogging the spots. 4) Apply the results of traffic research to tunnels and bridges which have heavy delays. Make all the traffic lights leading up to the tunnel reward 20mph driving, while at the tunnel exits it would reward 30mph driving. It's easy to force traffic to preset speeds like this using traffic lights, and you could do this for several blocks leading up to and away from the tunnels. In short - less frustration, less pollution, less circling around, people get to where they want faster, make more money and city is better off.
- superuser2 10y ago
  Street parking is just a terrible experience all around. I'd prefer to see most street parking eliminated in favor of dedicated rights-of-way for bikes, buses, taxis, rideshare, etc. If you want to have a car, you have to live somewhere that has an alley/garage space for you. If you want your business to be usable by drivers, have a parking lot or do a parking validation deal with a nearby garage. I think the SpotHero/ParkWhiz model is very cool, would love to see it turn into a real-time auction with very precise competitive demand-based pricing. "Parking is surging right now, consider taking UberPool for $x less." I already don't drive anywhere in Chicago unless I know there's an adequately sized parking lot, or I've booked reasonably priced parking ahead of time. Seeing ahead of time that there is no reasonably priced parking generally makes me take the CTA, whereas otherwise I might have circled for a while before breaking down and paying $25.
  - finid 10y ago
    > If you want to have a car, you have to live somewhere that has an alley/garage space for you. You're obviously not referring to NYC.
    - Symbiote 10y ago
      Why not? That's the case in the centres of many European cities.
      - finid 10y ago
        NYC is different. Most parking is street parking, or a paid garage parking, which can be expensive.
        Symbiote 10y ago
        > Most parking is street parking That's a decision the city has made, and the current state of much street-space in NYC. Copenhagen has made the opposite decision: space in the city centre is allocated to bicycle lanes and footpaths on many streets. I live on such a street. If I bought a car, I'd need to rent a parking space. London has an intermediate approach: resident parking on the street requires an expensive permit.
Natsu 10y ago
Yeah, but the funny thing about the all red timing that I've seen is that people can beat it by going faster than they should, which always struck me as wrong.
- eximius 10y ago
  I do exactly this. :/
WalterBright 10y ago
> This has been done for quite some time, and it's unclear what value deep learning would add beyond the arithmetic we've used for a while. I've seen a lot of these claims, and they're easily debunked by driving through a city. The usual case is a platoon of 5 cars cruising down an arterial. A solitary car pulls up on a side street, and the light turns read for the arterial just in time to stop the platoon for the solitary car. A sensible algorithm would let the platoon pass first. There are endless scenarios of these, to the point where the light algorithm finds a local optima where it is completely out of phase with the traffic and causes maximum delay and minimum throughput. A relatively small amount of effort going into cameras and an adaptive system that minimizes a cost function would save billions of dollars in gas, time, and unneeded road widening.
- Buttons840 10y ago
  There are two scenarios that inevitably get me thinking about smarter traffic lights. The first, is what you described, and the second is when I notice myself and a few others are sitting at a stop light while the intersection remains unused for 30 seconds.
- gwbas1c 10y ago
  Santa Clara, CA trumps out "retime the traffic lights" every time they want to raise taxes. Biggest crock of B.S. I've seen in a ballot.
- asynchronous13 10y ago
  > A sensible algorithm would let the platoon pass first. You're taking an example of a sub-optimal local solution and claiming that is proof that the global solution is sub-optimal. That does not follow. It could easily be, taking your example, that the platoon of 5 cars must stop at some future light, and the delay for 1 car is the smallest delay available for those cars. Therefore, stopping for the 1 car reduces the platoon's total travel time. As the driver, it's easy to think that was dumb because you'll never see the 15-car wait that was avoided by stopping early for 1 car. Essentially, you are claiming that a greedy algorithm for traffic would always find the globally optimal solution (which we know is not true).

gsmethells 10y ago

I think traffic lights are ripe for disruption.

lukiebriner 10y ago
You would think. However, even the current UK systems are nowhere near optimal. Crossings that block traffic for too long; Cycle crossings that stop for longer than pedestrian crossings; Lights that are at red even when there are no other cars. If councils are not motivated to optimize the current systems, they are unlikely to be interested in anything new and disruptive? There is also the pain of taking any new ideas through the approvals system, which I can only guess is both not easy and will be gamed by the larger companies.
- 7952 10y ago
  Outside my house is a crossing that waits until a gap appears in traffic before letting the pedestrian cross. Usually, by the time this happens I have already crossed the road (because a gap has appeared!). Optimising "traffic flow" only seems to cause an obstruction for local pedestrians and cyclists. The only real purpose of a crossing is to restrict pedestrians so that excessive vehicle traffic can be accomadated. They should either prioritise pedestrians or reduce traffic.

ajdlinux 10y ago

You mean https://en.wikipedia.org/wiki/Adaptive_traffic_control https://en.wikipedia.org/wiki/Adaptive_traffic_control, which we've used in every major jurisdiction of Australia starting in the 1970s?

deleted 10y ago
[deleted]
petepete 10y ago
In the UK too. Here's an interesting look at how vehicle detection works https://www.linkedin.com/pulse/20141005200312-83983163-traffic-signals-part-6-vehicle-detection https://www.linkedin.com/pulse/20141005200312-83983163-traff...

column 10y ago

https://xkcd.com/277/ https://xkcd.com/277/