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Safety Feature For Pedestrians Has Undesired Consequence

• mianosm 12y ago
  It is an interesting scenario that they play out in Toronto. However, this is a programmatic feature built into the traffic systems - and in the current location I live in completely different. Here the countdown hits zero well before the lights shift to yellow and finally red. Perhaps Toronto needs to readjust if there is a high number of rear-ends occurring due to drivers going off of the pedestrian control devices instead of vehicle control devices.
  • pierlux 12y ago
    Good point. Here for some reason the pedestrian light is 15 second even if the traffic is going to be flowing in that direction for 45 sec. You can hit the button and it'll start counting down again.
  • clarkmoody 12y ago
    My experience is that the light changes to yellow as the countdown reaches zero.
    • Fuzzwah 12y ago
      Here in Phoenix most work this way, but when a road crosses central avenue the walk counter hits 0 and then there is about a 10 second delay before the traffic lights change. The problem is, people have realized this. So peds continue to begin crossing as the counter gets low (central has a lot of ped crossing because the light rail runs down the middle of the road).
      • couchand 12y ago
        They really ought to reverse that. Make the light shorter for cars and drivers can no longer use the countdown clocks as a signal. They'd have to actually look at their own light. Combine that with starting the pedestrians early and you make it much harder for drivers to be jerks.
    • ams6110 12y ago
      I've seen both. On wide multilane roads I've seen the coundown hit zero and the "don't walk" signal come on before the traffic light changes to yellow. On narrower crossings the yellow tends to appear as the counter hits zero or very shortly after.
  • scott_s 12y ago
    That's similar to what I've seen in the NY suburbs; I've noticed that the counter hitting zero is when the traffic light goes yellow.
• learc83 12y ago
  Seems like they could easily fix this by installing some kind of small plastic guard to keep most cars from seeing the countdown.
• __david__ 12y ago
  Seems to me they could put blinders on the crosswalk timers so they are only visible from the corner and not from the middle of the street. They already often do similar things to left turn lane arrows (so that when you aren't turning left you don't see green out of the corner of your eye and jump the gun).
  • lotharbot 12y ago
    As a driver, I really like these timers. I can see from a block away that I've got 15 seconds (and will make it comfortably) or 2 seconds (and may as well slow down now since I won't be anywhere close). As long as the blinders weren't too restrictive, my use case would still be viable.
    • angersock 12y ago
      That's exactly the use case that they caution about--drivers at different distances interpreting the signals differently, causing accidents.
      • lotharbot 12y ago
        The use case they caution about is drivers reacting suddenly to short clocks -- flooring it or slamming on the brakes -- when they're very close to each other. They're talking about how people react to a "2" when they're 2.1 seconds away from the intersection and right on somebody else's tail. I'm talking about reacting from a long distance out by subtly adjusting speed (obviously in conjunction with reading traffic -- you don't accelerate if there's a vehicle right in front of you.) If you're 10 seconds out and see a 2, there's no differential reaction, likewise if you're 10 seconds out and see a 20. Even if you're 10 seconds out and see a 9, the difference between "slight acceleration" and "slight touch on the brakes" isn't significant unless you're already driving too close for the circumstances I drive under.
  • baddox 12y ago
    I've never seen a normal intersection where the pedestrian timers are visible to the drivers that are driving on the same road the pedestrians are crossing. The pedestrian timers are always lights behind a direction grill. I suppose the problem could manifest for drivers wanting to turn onto the road the pedestrians are crossing, or strange intersections where the angle of intersection is far from 90 degrees.
• ryusage 12y ago
  Weird. I wonder if this is primarily a problem in larger, more congested cities where people tend to drive more aggressively. I live in a smaller city where we've had these a very long time, and they don't seem to inspire the kind of behavior they're talking about here. But driving here is also significantly less aggressive than somewhere like, say, Chicago.
  • acdha 12y ago
    I'm sure culture matters a lot - here in DC, there's no stigma or enforcement against running a red light or blocking the box so people do it all the time. This kind of behaviour is completely unsurprising but will probably reverse as the number of red light cameras goes up significantly.
  • aidos 12y ago
    I wonder if there's any weight to that assertion of a correlation between city size and aggression. I live in London and I generally find that the behaviour is surprisingly courteous. My suspicion is that it's because many (most?) roads are actually too narrow to have two cars pass at the same time so people are very used to having to pull over to get out of each other's way. Obviously, all totally anecdotal, but there must be some research on it.
• bjchrist 12y ago
  Can't wait till we get self-driving cars. Next generation will find it completely reckless that we put people in charge of driving cars
• datr 12y ago
  I'm having trouble understanding this article. If the count down timers show pedestrians the amount of time they have to cross the road (as they do here in London) why would the driver be watching this and think they only have a few seconds until the light goes red and they can't get through the intersection. Surely, the opposite is the case? I can see that you could potentially form a similar explanation around that scenario too but it doesn't seem as convincing.
  • ealexhudson 12y ago
    I'm assuming this has something to do with being able to turn through a red light, which is illegal in London. But yeah. I had trouble understanding the issue at all, as you note London has them, I've never noticed any issue at all - if anything, it gets the peds out of the road more timely...
    • joncrocks 12y ago
      Indeed, in England pedestrians never cross when a vehicle has a green light over the path they are going to cross. I.e. completely separate pedestrian phases. In the US, the walk lights go 'green' at the same time as traffic parallel to the crosswalk gets a green light, in a shared phase. So if the timer is getting close to zero, it means the vehicles are about to go to a red light, and the opposite direction is about to get the green light.
      • vidarh 12y ago
        I'm a bit unsure exactly what it is you are describing. Pretty much all the crossings I use regularly in London follows an at least very similar pattern to what I'm used to seeing in the US when visiting, with traffic parallel to the crossing getting green at the same time as the pedestrian crossing in question In fact, here's a discussion in the UK Parliament in 2004 where it was proposed to restrict the use of all-red phases in low traffic junctions, and where the person proposing the change saw it as necessary to describe why this was even an issue: http://www.publications.parliament.uk/pa/cm200304/cmstand/a/st040210/pm/40210s05.htm http://www.publications.parliament.uk/pa/cm200304/cmstand/a/... "Mr. Redwood: Until a few years ago, no one would have understood why new clause 5 would be necessary. All traffic lights that motorists or cyclists encountered on our highways had a simple form of operation which meant that there was always one free route across the junction showing green. In the normal four-way junction where two roads intersected, one road had priority for one phase and the other road had the alternate priority. There could be more complicated variations at larger junctions, but there was always a green phase for vehicles on one part of the junction" [The proposed clause 5: 'No authority shall be entitled to install or operate traffic signals with all red phases at road junctions where there is no hazard other than traffic.'] You may be right that no vehicles will have green light to cross the pedestrian crossing while pedestrians have a green light, though I'm not 100% sure that's true either - I seem to remember crossings in London at least where turning traffic will have green at the same time as pedestrians, but I don't drive so maybe that's just me as an impatient pedestrian misremembering, as I'll regularly cross on red.
• miketesch 12y ago
  It's possible that the lowered rate of accidents involving pedestrians can at least partially be attributed to the fact that drivers can see the timers.
• taylorjbrennan 12y ago
  In this context, it's a "cheat" for drivers with greater awareness, and one can't assume the driver in front knows to accelerate. Perhaps it would be safer if the timers were installed on the drivers' traffic lights as well. I've seen them in China and I liked the idea. What's stopping automobile traffic timers from being installed in the U.S.?
  • Fuzzwah 12y ago
    We have pedestrian walk timers here in Phoenix and they are very easy for drivers to see. The situation described in the article happens when a driver is approaching a traffic light which is green but notices that there is only 1 or 2 seconds left on the walk count down and decides to stop. A driver behind, who may or may not have seen the count down isn't ready for a car to begin stopping as it approaches a light which is still green. Bang.
    • jessaustin 12y ago
      So the problem is not aggressive driving, but tentative driving? Wow. Actually drivers have a duty to stop for vehicles ahead of them at any time. So the rear-ender, not the rear-ended, is at fault, even if the rear-ended was doing something dumb like looking at pedestrian signals.
    • adnrw 12y ago
      I think you've slightly misrepresented the second driver's intentions. The article says: "...the guy behind, he sees the two or three seconds and thinks, oh, the guy in front of me is going to floor it too, I'll floor it and we'll both get through the intersection. Whereas the guy in front thinks, OK, I only have two or three seconds left, I'm going to slowdown." So it's not that the driver in front sees the timer and stops during a green light, whilst the driver behind doesn't see the timer and isn't expecting to stop during a green. More likely that both drivers see the timer and make conflicting decisions: the driver in front decides there isn't enough time and slows down; the driver behind decides there is enough time and speeds up, having assumed the driver in front would be doing the same. However, your scenario is plausible too and just as problematic.
• Retric 12y ago
  In the trade off between property dammage and pedestrian deaths I am generally going to side with pedestrians.
• brownbat 12y ago
  Even if we don't get fully self-driven cars soon, I really hope we get autopilot to take over for timing left turns and yellow lights, entering a highway, avoiding pedestrians, and maybe all parking. Sure, many drivers handle that all fine most of the time, but each one seems like a potential point of failure that would benefit from a little more standardization. EDIT: Or traffic robots that direct instructions to proceed or stop to each specific driver. Seems like we have better options than a colored indicator involving a lot of judgment calls based on conflicting interests.
• ripter 12y ago
  It reduces the number of pedestrians who get hit, and asshole drivers who think they can speed though intersections are getting into accidents. I don't see the issue.
  • spectralwarp 12y ago
    It has been shown that accidents can occasionally hurt innocent people.
  • diminoten 12y ago
    Who do you think the asshole drivers run into? According to the article, drivers who are just trying to be safe by not risking it and slowing down get hit by drivers behind them who speed up.
    • jessaustin 12y ago
      ...drivers who are just trying to be safe... If their idea of safety is paying attention to pedestrian signals rather than automotive signals, we'd rather they not bother.
      • diminoten 12y ago
        Who said anything about "rather than"? What kind of a signal do you expect someone about to rear-end you to give?
        • jessaustin 12y ago
          They should be looking at the signal that consists of a red lamp above a yellow lamp above a green lamp. While the green lamp is lit, they should keep driving and not slam on the brakes just because the little man in the crosswalk started blinking. Yes I know that rear-enders are at fault even when the rear-ended did something stupid. In fact many driving accidents can be attributed to the stupidity of multiple parties, and the accidents described above can also be so attributed.
• jrockway 12y ago
  Even when the intersection doesn't have the countdown timer, I memorize the number of "hand flashes" before the light changes and use that to figure out if I need to speed up to get through. This is on a bike, though, so hardly life threatening. The timers are actually very convenient, especially in New York with long yellows and long 4-way reds. 1 second? More than long enough.
• incision 12y ago
  I sit above a pretty busy intersection and get to witness the madness and regular accidents of rush hour traffic heading out of downtown on a daily basis. I think simply shimming an extra second or of intersection clearing time between transitions would go long way towards addressing the apparent dangers of light timing. Activating traffic signals and pedestrian signals simultaneously results in drivers who try to 'beat' the pedestrians off the curb. Activating perpendicular traffic signals too close traffic/pedestrian signals puts the cross-traffic in danger of being hit by the people trying to time the light. Add a second or two, end up with <5 fewer light transitions per hour. Though, on a related note, what I see cause more accidents and general bullshit than timing lights is the ridiculous amount of cellphone use that happens in motion and particularly at intersections. Every day I see someone stop at the red light below me and immediately start fiddling with their phone, as the light turns green and the fiddler proceeds to hit the gas irrespective of what is happening in the road directly in front of them - pedestrians, gridlock, presidential motorcade only to run into something or panic stop seconds later if they're lucky. At first this seemed inexplicable..."Can't these people see?" Upon thinking about it, I'm guessing they actually can't or more accurately don't see. That the fraction of a second they have to hit the gas before getting a chorus of horns or a rear-ending is simply too short to take in even major changes in the scene in front of them. Self-driving cars can't come soon enough.
  • seanmcdirmid 12y ago
    If you live in a culture where disobeying traffic signals is common (especially non-drivers...say in China...), you observe that people become much more cautious about light transitions. I always cringe driving back in the states and just going as soon as a light turns green. A kid rushing after a ball into a crowded street in the US is probably dead meat. In China, they have a much better chance of surviving because drivers are used to that crap (likewise for pedestrians and crazy drivers). Though I would venture that the fatality rate is still much higher China (I've personally seen people get hit and killed).
  • fredophile 12y ago
    I've never seen an intersection that didn't have some amount of time where it was red in all directions during a light change. I can't find references to back it up right now but I'm pretty sure that in cases where this period is extended you end up with drivers adapting and driving through a stale yellow that they would have previously stopped for.
• foobit 12y ago
  I like how traffic is kind of organized in Paris: Pedestrians will cross the street whenever they feel like and don't care much about the signals. Because of that car drivers will constantly watch out for jaywalking people, drive with responsible speed and rather stop too often than being cited for reckless driving. All in all this works out extremely well and I always feel like this the safest city for a pedestrian.
• logicchains 12y ago
  Why can't they just install more speed-bumps? Scientifically calibrated so that they only cause damage to cars going beyond an acceptable speed for the particular intersection in question. I used to live somewhere hoons would regularly speed by; a speed-bump was built, and it put an end to such speeding almost instantaneously as all the hoons had their vehicles' suspension destroyed.
  • Anechoic 12y ago
    Why can't they just install more speed-bumps? Off the top of my head: - Given the variety of suspension systems in cars (and available aftermarket options), trying to make a speed bump targeting one speed (or even a relatively narrow range of speeds) would be pretty difficult unless you want to limit all traffic to 10-15 mph - Speedbumps on major thoroughfares can cause problems for emergency vehicles - (from personal experience) riding over a speed bump (certainly ones that haven't been well-maintained) on a bicycle is not fun - they make snowplowing more difficult (but not impossible)
• jcampbell1 12y ago
  I'd like to see a study of red light countdown timers. I have only seen them in China, but I think they are awesome. The timer tells you how long until the light turns green. If it is 30 seconds, you can check your text messages, or adjust the radio, but when it hits 3...2...1... everyone goes at the same time. I have never seen so many cars make it through an intersection in a single light cycle. I have a feeling it is good for safety as well because drivers get some downtime, and a timer that lets them know when they need to be back at full attention.
  • tacticus 12y ago
    And then you have the dicks who will move at -1 second and jump the lights without checking that it is clear.
    • PeterisP 12y ago
      Well, this can be solved by well-known practices of red light cameras and revoking licences for repeated violations. I mean, what you describe isn't a problem with timers, it's a problem with some dicks that are dangerous to others (not only in this situation but others) and should be prevented from driving at all.
• seizethecheese 12y ago
  Why don't they just retrofit these signals so that pedestrians can see but drivers can't?
• WalterBright 12y ago
  With all this focus on self-driving cars, nobody is looking at the low-hanging fruit - cameras on the traffic lights. No, not for ticketing people, but for changing the signals in a way that maximizes flow. This will save time and an awful lot of gas. With all the sophisticated camera algorithms these days, this should be a relatively simpler problem to detect the speed, number, and distance of cars coming from each direction. It can also be used to save lives - the light for the cross street need not turn green when the other turns red if there looks like a car is going to run the red. If there are pedestrians in the intersection, the lights can also remain red.
  • robryk 12y ago
    You can detect speed,ount and types ofcas with a pair of inductive loops (car length determines the type pretty well). I'd guess that putting such a pair some distance before the intersection would be a lot simpler (cars would obscure each other in the camera's view). That said, this would give you information about cars passing a single point on the road and would give you no information about pedestrians.
    • mpasternacki 12y ago
      This has been implemented for some traffic lights in Warsaw, and has one more bad side effect (possibly because of bad implementation): if you a bike in the late evening on the smaller street, that's configured "red unless there's a car that will be crossing" to maximize throughput of the bigger street, you have to wait for a car or use a pedestrian crossing, because the loops won't detect a bike.
      • mnw21cam 12y ago
        Lots (most?) of the traffic light controlled junctions in the UK have induction loops to detect cars. I have personally complained to the authorities about their lack of ability to detect bicycles.
    • WalterBright 12y ago
      Inductive loops, wires, maintenance, etc., are far more expensive than a $10 camera, once the software is developed.
• nisse72 12y ago
  Here in Auckland, I think we only have those countdown timers at intersections where pedestrians can cross in all directions at the same time, so there are no cars speeding up to make the light, all of the cars are stopped.
• barrystaes 12y ago
  Good grief.. the article ends with "Install them so that the pedestrians are aware of the timers but the drivers are not. And one way to do that would be to broadcast the timers via audio so that the pedestrians can hear the countdown clock go down, but drivers cannot." The defacto standard in the Netherlands is that a pedestrian stop makes a loud ticking sound to aid blind people. When its about to jump to red (lets call this orange) the pace increases, before going calm (not loud, and low pace) when the light is red. The orange period is -say- the time it takes an elderly lady to cross the street. Here, we dont need countdown displays. People should be able look at the oncoming traffic instead.
  • walshemj 12y ago
    quite a lot of lights in London (uk) have a count down for the pedestrian side - its just the nutters on fixed wheel bikes who blast through junctions at 25-30mph you have to watch for. If you think I am kidding about the fix wheeled bikers visit the junction next to Holborn tube.
• stuaxo 12y ago
  In London we have the opposite, timers for how long you are allowed to cross, this probably makes more sense.
• GotAnyMegadeth 12y ago
  There are/were a couple of junctions in Phnom Penh where the traffic lights for the roads have count down timers on both the green and the red. All the motorbikes started going around the 5 second mark meaning there was a good few seconds of everyone going from both directions. I'm sure it's pretty dangerous, but it was fun to navigate