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200k Flemish drivers can turn traffic lights green

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Re: 200k Flemish drivers can turn traffic lights green

#81

Post by kazinator »

kuon wrote: post #56

Here (switzerland) lights turn red on purpose to slow down traffic. The idea is that if you see a green light in the distance, you are motivated to speed up to catch it before it turns red. If it is red in the distance, you slow down because you eventually have to stop, and when you are like 20m from it, detectors will see you and turn it green.

Sounds like they never heard of Goodhart's law. They rigged a system which measures behavior (distance of approaching vehicle) and tied it to decision making (controlling a traffic light) in order to create an incentive toward a certain desired behavior. That's a prime example of something where people will learn the system and game it to optimize their own advantage instead of the desired behavior.

Re: 200k Flemish drivers can turn traffic lights green

#82

Post by kortilla »

SteveNuts wrote: post #74
0_____0 wrote: post #65

Earlier quoted context omitted.

Or by doing even a slight amount of encoding of the IR signal. Transmitting a single byte as a key (set by region, same as fire dept. elevator keys) would be enough to prevent people from using their TV remote controls or whatever to trip the preempt sensors. That being said, this is kind of a non-issue already, I have heard a story about someone abusing the preempt sensors like 10 years ago and never since then. May…

Anecdotal of course, but in my 20 years of driving I've never once seen a vehicle activate the red light override sensors that wasn't obviously a legitimate emergency vehicle. IMO a huge majority of people realize how illegal it would be to mess with these things, and the risk/reward is very low. Anyone who would take that risk would probably just run a red light instead.

It’s a pretty serious federal crime to impersonate an emergency vehicle at those. So definitely worth just running the red.

Re: 200k Flemish drivers can turn traffic lights green

#83

Post by ChrisMarshallNY »

As far as emergency vehicles go, we have had a system in place, around here, for years, where the vehicles have some kind of infrared device that forces the light green.

Bit annoying, when you are in a cross street, and you know it's about to turn green, then an ambulance comes by, and it skips your turn.

I think there's also a black market for the devices for impatient drivers.

Re: 200k Flemish drivers can turn traffic lights green

#84

Post by gruez »

Ajedi32 wrote: post #76
phkahler wrote: post #71

Earlier quoted context omitted.

I don't understand why they need apps for this either. The infrastructure should be in place to detect cars approaching from the side street. Once they have the ability to detect cars, it's simple to assume everyone would be requesting a green light.

Presumably the app would be able to signal the presence of an approaching car from a much longer distance than the inductive loops you typically see these systems, ensuring cars don't even need to slow down when approaching the intersection. (Saving gas, brake/tire wear, and time.) It's also probably cheaper than the extra physical infrastructure needed for inductive loops, given that all the necessary equipment (pho…

>It's also probably cheaper than the extra physical infrastructure needed for inductive loops, given that all the necessary equipment (phones, GPS, cell infrastructure) is already in place for most people.

Assuming the procurement/contracting for said app is done competently, which seems questionable for most governments. Moreover even if it's cheaper, surely some sort of camera/sensor setup would be safer than drivers fiddling with an app?

Re: 200k Flemish drivers can turn traffic lights green

#85

Post by tikhonj »

rob74 wrote: post #69

> A simple example: at night, a main road mainly displays green, the side streets only get green for a very short time. If you arrive with the app from a side street, you can get green immediately, provided there is no traffic on the main road. In Germany, there's an established but much more low tech approach to this problem: simply turn off the traffic lights at night! All traffic lights already have yield/stop/pri…

Oh, I remember this used to happen in Berkeley. Not sure if it stopped, or if I just stopped walking outside late enough to see it :P

It totally makes sense as an approach. No point in having normal traffic light cycles on low-traffic streets at 2 AM.

Re: 200k Flemish drivers can turn traffic lights green

#86

Post by TYPE_FASTER »

OtherShrezzing wrote: post #13

I have no idea why the app is required here. Cars & bikes are massive, hot, & mobile objects. They're perfect for a modest-cost IR sensor atop the traffic light to detect them and adjust the lights accordingly. This type of system is commonplace in cities in the UK and works effectively. Having drivers reach for their phone when they're approaching traffic lights - common pedestrian crossing points - is categorically…

Do bicyclists and pedestrians really require the use of sensors? There are a lot of paths around me that cross busy roads with traffic signals. We just press a button. It speaks after you press it for visually impaired users and shows a red light after you press it for audibly impaired users.

Re: 200k Flemish drivers can turn traffic lights green

#87

Post by Ajedi32 »

gruez wrote: post #84
Ajedi32 wrote: post #76

Earlier quoted context omitted.

Presumably the app would be able to signal the presence of an approaching car from a much longer distance than the inductive loops you typically see these systems, ensuring cars don't even need to slow down when approaching the intersection. (Saving gas, brake/tire wear, and time.) It's also probably cheaper than the extra physical infrastructure needed for inductive loops, given that all the necessary equipment (pho…

>It's also probably cheaper than the extra physical infrastructure needed for inductive loops, given that all the necessary equipment (phones, GPS, cell infrastructure) is already in place for most people. Assuming the procurement/contracting for said app is done competently, which seems questionable for most governments. Moreover even if it's cheaper, surely some sort of camera/sensor setup would be safer than drive…

I'm guessing they wouldn't need to fiddle with an app; the software would just automatically signal their approach based on GPS/navigation info.

I agree theoretically a camera + machine-learning based system could work just as well; I've always wondered why that wasn't standard on traffic lights these days given that the hardware would probably cost a few hundred dollars (if procurement for said hardware were done competently, which I suppose as you said, it probably wouldn't be).

Re: 200k Flemish drivers can turn traffic lights green

#88

Post by helsinkiandrew »

gruez wrote: post #84
Ajedi32 wrote: post #76

Earlier quoted context omitted.

Presumably the app would be able to signal the presence of an approaching car from a much longer distance than the inductive loops you typically see these systems, ensuring cars don't even need to slow down when approaching the intersection. (Saving gas, brake/tire wear, and time.) It's also probably cheaper than the extra physical infrastructure needed for inductive loops, given that all the necessary equipment (pho…

>It's also probably cheaper than the extra physical infrastructure needed for inductive loops, given that all the necessary equipment (phones, GPS, cell infrastructure) is already in place for most people. Assuming the procurement/contracting for said app is done competently, which seems questionable for most governments. Moreover even if it's cheaper, surely some sort of camera/sensor setup would be safer than drive…

The drivers don’t “fiddle with an app”. The apps use geo location to notify the traffic control system when they are near an intersection.

https://www.brusselstimes.com/512118/flemish-traffic-lights-...

> As soon as a driver approaches an intersection with smart traffic lights, a signal is sent via their app and the cloud to the computer controlling those traffic lights.

Re: 200k Flemish drivers can turn traffic lights green

#89

Post by 6510 »

I've been pondering this since the 90's. In my imagination the ultimate form is to have an auction with auto-bidding and minimum bids. If you haven't money you configure the app to collect only with a low minimum bid. When wealthy you have everyone wait for you. For example: From one direction 20 cars are approaching the crossing. Only 1 from the other direction. From the 20 car direction the highest minimum bid is 5 euro. For the single car to get priority they would have to pay 100 euro. The money goes in the other drivers account.

Manual control is also possible. The wait time is displayed on the dash along with the fee. If the fee is below the configured maximum you can press a green button, if there are no higher auto-bids the light will turn green. If there are the fee increases for you to press the button again.

It would finally provide a fun game for people with high testosterone issues so that they can assert their dominance by handing out free money. That you own a fancy car doesn't mean you get to go first, I have more money than you therefore you should wait while watching me cross the crossing. The old lady behind the Bentley also gets 500 euro in her account.

Re: 200k Flemish drivers can turn traffic lights green

#90

Post by gruez »

rob74 wrote: post #66
kuon wrote: post #56

Here (switzerland) lights turn red on purpose to slow down traffic. The idea is that if you see a green light in the distance, you are motivated to speed up to catch it before it turns red. If it is red in the distance, you slow down because you eventually have to stop, and when you are like 20m from it, detectors will see you and turn it green.

My experience as a cyclist contradicts that: many motorists will still (riskily) overtake you just to reach the red light sooner. Some people apparently just can't stand to have anyone driving before them. See also: people passing by you on a multi-lane highway and then promptly slowing down once they have returned to your lane...

>My experience as a cyclist contradicts that: many motorists will still (riskily) overtake you just to reach the red light sooner. Some people apparently just can't stand to have anyone driving before them.

???

Seems like the far more plausible reason is that drivers don't want to be held up by a cyclist traveling at 10mph in front of them? Moreover if it's really true that lights only turn from red once a car reached them, then it makes sense to maintain speed (including overtaking any bicycles), because getting to the light faster means it turns to green sooner.

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