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Unintended Consequences For Traffic Safety Feature
An anonymous reader writes: Traffic engineers had a problem to solve: too many pedestrians were getting hit by cars while using the crosswalks at intersections because they didn't know when the 'WALK' sign would change. Their solution was simple: implement a countdown timer. Countless cities have now adopted these timers, but it turns out to have an undesired consequence: motor vehicle crashes are actually increasing at intersections where the countdown timer is used. Researchers think this is because pedestrians aren't the only ones who see the timers. Drivers see them too, and it provides them with information on when the light will change. Then they anticipate the change by either speeding up to beat a change to red light, or anticipating a green light in order to get through before the pedestrians can move into the road. The researchers suggest finding some way to hide the countdown from the drivers, perhaps through the use of an audio countdown that would be difficult to hear from inside a car.
Please don't do an audio countdown. It doesn't work for us hard of hearing people.
Make angled sides on the signal to that you can only see it from like a +/- 5 degree angle, or less, and use sounds for the blind.
When you cant win, ad hominem.
Since they can't hear, maybe they should use a flashing light, oh wait...
Computers will fix this kind of thing by default.
The dangers of knowledge trigger emotional distress in human beings.
Drivers need to pay attention to the road, there is no excuse for hitting a pedestrian in a cross walk or for a car to hit car at a cross walk. Drivers need to grow up, pay attention and stop blaming everything but the lack of driving ability.
The driver should only score half points...
Worst. Signature. Ever.
In atlanta at least, the countdown is already accompanied by an audible chirp.
Intended for blind or otherwise disabled folks (except deaf folks, naturally), it also serves as a cue for regular folks as well to hurry up on some of hte larger/wider intersections.
Really all that should be fixed is to put a bigger gap between the countdown reaching 0 and the light actually changing. My experience with signal timing (and this is my trafic engineering schooling showing through) is roughly half-half: about half the intersections I saw with the countdown change immediately, others still have the standard 4-5 second "intersection clearance delay" between the countdown ending, and the light actually changing. The clearance delay exists for obvious reasons to put a delay between one side turning red and another green. It should simply also take the crosswalk into consideration as well as a best practice.
The guy who said the election was rigged won the presidency with the second-most votes.
Put a small shield along the side of the timer so the drivers can't see the timer.
I know, I know, the solution doesn't involve some convoluted, drawn out, highly technical, over-engineered process so it will never be implemented.
Instead, we'll go out of our way to find the most convoluted, drawn out, highly technical, over-engineered, and expensive, solution and claim we're making progress.
We will bankrupt ourselves in the vain search for absolute security. -- Dwight D. Eisenhower
In Ca, it's a ticket if a car enters a crosswalk while a pedestrian is using it, no matter if they're on the other side of the intersection or not. And the new walk signals have a visor around them so unless you're almost directly in front of it, you can't read it. They also started using audio signals, which beep and talk, for the blind.
...is they try to fix human behavior via engineering, but people can't really be engineered.
For example, in my home town we had a roundabout from hell. Five highways came into a loop via offramps. Literally once a week there would be an accident and once a month it was a fatal one.
So some brilliant traffic engineers tried to solve the problem by creating off ramps for each other highway. At highway A you could choose to offramp to highway B, C, or D. But the "offramps" used the roundabout, which now had concrete dividers about curb height. The mayor, the local press, and local government kept trumpeting how many lives this would save.
Well, turns out the only thing more dangerous then five highways going into a giant roundabout is five highways going into a roundabout with concrete dividers to slalom around. Accidents became a daily occurrence and fatalities went up.
As it turns out, people are stupid. Sure, if you are new to town and take the time to slow down to read the sign, and drive carefully, you can figure out where you're going. But people zip in at highway speeds, apply the brakes quickly, and try to swerve over.
The problem is not one of engineering, but one of behavior. Modifying the behavior (via police enforcement) would be more effective then a fancy solution.
Before seatbelts people drove much more cautiously because they didn't want to be impaled by their steering column in a crash or tossed through their windshield to become stuck in a tree. Thus we introduce seatbelts and eventually legally require them for safety -- but what happened is car crashes skyrocketed because drivers felt safer while strapped in so everyone started driving more irresponsibly.
When it is time to cross the crosswalk the underpants gnomes jump out and steal your underwear, they then run to the other side of the road and furiously wave them at you yelling "Come and get them you scaredy chicken!" Then they put the underpants on their head like a roosters comb and tuck their fists into their armpits to mimic a chicken walk. So you run across the road to beat the living daylights out of the gnome and the gnomes immediately toss your underpants into the air and they make a run to the next available crosswalk, leaving you to scramble to pick up you underwear. After a short breather you realise you have successfully crossed the street.
Sorry for the troll but I am having a bad day and have to keep myself in check I post here.
I knew the underpants gnomes were useful for something.
A better solution might be to remove the signals altogether. Several European towns have tried shared-space experiments where there are no signals or markings and the pedestrians and vehicle drivers have to actually watch out for each other. In all such experiments so far, traffic fatalities have dropped significantly.
How about doing what other countries do and giving drivers our own damn timers to let us know when our lights are going to change?
If I have been able to see further than others, it is because I bought a pair of binoculars.
It has helped. Can you not read or something?
So the opposite of "not helped", it worked just fine.
However, in addition to reducing the number of pedestrian accidents it also increased the number of rear-end collisions.
Actually, I've personally witnessed drivers screw up at these intersections by watching the wrong cues. A few months ago a driver rolled out into the middle of the intersection because they thought that when the cross traffic light turned red, our light would turn green (no, the left-turn only lane light goes first after cross traffic). I know that's what they did because I was watching the light too, except this is the last intersection before I get home so I know what the light pattern is. Because the light pattern changes depending on time of day and whatever bug crawled up the traffic engineer's ass that week, when you're watching the other lights, you still have to verify your light before you go.
Ideally we'd get our own countdown timer to let us know whenever the signal is going to change. Staring at a red light for 45 seconds is boring, you can go ahead and insist that we change human nature, or you can go with human nature and give us something to pay attention to.
If I have been able to see further than others, it is because I bought a pair of binoculars.
Removing The Traffic Lights
The most dangerous place to cross a street is at an intersection. Pedestrians have to look in 4 different directions to be sure no cars are going to hit them. Drivers have to consider the same 4 directions. But if you walk across the street half way between intersections, then you only have to consider cars coming from TWO directions. I did the math, and that's half as many ways you have to look.
As a pedestrian who nearly got hit recently (while crossing at an intersection, WITH a walk signal--and yes, I took the initiative and moved out of her way before she hit me), this has seemed obvious for quite a while now. I will admit that if we made this official, it would cause more work for drivers, as they would have to be on the lookout in twice as many places. But it beats getting hit.
Think of it this way: It's not jaywalking, it's civil disobedience! There, much more amenable to slashdotters! 8-)
Here in Bulgaria we have many (in fact, most) traffic lights with countdown timers for cars. Most don't even have timers for pedestrians. And these timers started to appear about ten years ago.
I haven't heard of increased car crashes at intersections. My own observations also don't point in this direction. People are (or at least I am) using these timers as a more precise yellow light. And drivers in Bulgaria don't have to twist their necks in order to see them. Maybe this is the problem?
Disclaimer: Bulgaria has a very high fatality rate on intercity roads. These are not related to traffic lights, though.
My town has been adding these countdown timers to most stop lights. They are fantastic for drivers. You can tell if you need to speed up or go ahead and break for the impending red light. I no longer have to slam my breaks for surprise yellow or red lights. I suspect once people learn to time their stops based on the clock, quick stop accidents and red light run accidents (much more serious) will actually decrease.
In some areas of Portugal we have exactly the opposite - timers applied to traffic lights instead of crosswalks. In some places we also have crosswalk timers together with traffic light timers.
Why is this a solution? Because drivers will stop paying attention to crosswalk timers and use their own traffic light timers instead, which have a security offset of 1-3 seconds. This not only makes standing at a traffic light much more dynamic and time-efficient (drivers will know how long they have to do imprudent things like fixing a rear glass, looking at the mirror, texting or picking something out of a glove box, with a high degree of safety), but it also prevents them from prematurely hitting the gas, as most drivers feel it is unsafe to go before the timer hits 0.
Also, the timer works in both waiting for a green and waiting for a red. Yellow lights could be fully substituted by a red and green light only with a timer which would turn yellow on the last 1-3 seconds before a red. It would also prevent a lot of ambiguity in yellow light ticketing which is very common in urban areas and is reason for dispute between veteran drivers and over zealous traffic authorities.
Then you also take away opportunities to be a gentleman. :(
Good. I've seen drivers behaving as "gentlemen" inadvertently cause a considerable number of near misses. Not as many as asshats cause, but quite a few. The thing is, drivers should be predictable. It might appear courteous to let someone out of a side road, but it's not usual. As soon as you start behaving differently from everyone else on the road, you cause a degree of confusion. And confusion among drivers is sometimes lethal.
So next time you're tempted to be unnecessarily courteous, don't. The driver you want to let out of the side road will get out just the same in a minute or so, and there will be reduced opportunity for confusion among other drivers around you. The most gentlemanly and considerate thing to do overall is to drive predictably, and hopefully self driving vehicles will improve that.
Easy fix for this. Just make sure that as soon as the light turns red, big steel spikes come up from under the road to stop or pierce any car that might try to outwit the system. Oh, and on both sides of the street to ensure that real high-speed idiots will be caught on the other end.
To Terminate, or not to Terminate, that's the question - SCSIROB
Thus we introduce seatbelts and eventually legally require them for safety -- but what happened is car crashes skyrocketed because drivers felt safer while strapped in so everyone started driving more irresponsibly.
Do you have any data to support this assertion? The data we do have clearly shows that highway fatalities have dropped DRAMATICALLY since seatbelt installation, and later use, became mandatory. In 1967 (the last year before all new cars were required to have seatbelts, the US had 5.26 traffic fatalities per 100 million vehicle miles travelled. Fifteen years later (by which time virtually all cars on the road had seatbelts, given the lifespan of a car), that rate was 2.58, or down more than 50%. Even if there was some level of increased reckless driving (which, again, you've provided no evidence for), the NET impact was dramatically positive.
I love these crosswalk countdown timers at intersections. Perfect for letting you know if you can make the light or need to forget it and brake. I'm not sure how the timers are increasing pedestrian fatalities, since the only people crossing should be with the flow of traffic, not across it.
Not all crashes are created equal. Simply stating "Crashes increased" means nothing. Scratched paint? Were they fatal? The perfect example are roundabouts. When they were introduced in the US years ago, the number of accidents in those intersections actually increased rather dramatically. People were up in arms, but then the statistitions came out and explained that while the number of accidents increased, they were on average far more minor incidents. Mostly side swipes and such. It was damned near impossible to get into a fatal car crash in a roundabout. Compare that with our old red light system where accidents are very often bad enough to total both cars and are frequenty fatal and suddenly that increase in total accidents doesn't seem so bad.
It all depends on just how much impact shittyness has. In this case, jerks are resulting in the deaths of other people. So the lives of some have to be weighed against the fun of others. It is a balance that is looked at in many areas of life (since pretty much any activity has accidents), so the question of what should or should not be done when it comes to cars is far from simple.
Hahaha I never heard of this before so I watched some vids: https://www.youtube.com/watch?...
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wrong for USA, violation of law for pedestrian to walk against light, look it up. In fact, proof of pedestrain walking against light can get aquittal for manslaughter charges by driver. We can't have pedestrians clogging big city traffic if they think they can loiter out in intersection at any time with impunity. move it or lose it!
It's just as annoying when there's nobody behind them. The person entering the road (or pedestrian crossing) could have gone sooner if the car had just kept going and gotten out of the way, instead of needing to wait to make sure the car is going to stop for you.
Is this related to the dumbasses who wave at you to go when you don't have the right of way? I see this all the time around here at 4 way stop signs. Sometimes they wave me on to go ahead of them when they have the right of way, sometimes they do it when I clearly have the right of way. I don't need your stupid waving. I learned how stop signs work as a requirement for getting a drivers license.
The worst are the people who will stop before an intersection to allow you to make a left hand turn. On a road with two lanes in each direction and themselves in the left hand lane, so that your view of the oncoming traffic in the right hand lane is blocked. I can only assume they are waving me on because they want me to crash into the car in the right hand lane, who did something to piss them off previously.
Ideology: A tool used primarily to avoid the bother of thinking.
When I first saw them appearing, the "unintended consequence" of drivers using them was immediately obvious and appreciated ;-) Such use is no excuse for an accident though - only an idiot doesn't make sure some other idiot isn't on a collision course before going into an intersection. It's as bad as the people suing the state of Oregon because an expansion joint on a curved overpass in the Portland area is a little uneven - cars hop a little going over it, but if you're not going way over the speed limit, it's not a problem and thousands of cars handle it every day. But a few idiots couldn't and now that it's made the news, here they come out of the woodwork.
As a driver, I like those timers. After a couple of seconds, I've got a very good idea where I'll be when it hits zero. If it's not at the intersection yet, I can slow down easily, or otherwise I can just continue. None of those split-second decisions when the light just turns yellow. (Yeah, I know about mentally setting a go/nogo point when coming to a DON'T WALK. I'm just not that good at it, historically.)
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
Maybe people who are easily confused should not become drivers? A safe driver should always expect the unexpected.
Really. US road design is stupid and traffic lights are cretinous. Sudden changes from green to yellow force drivers to make a split-second decisions and quite often drivers simply respond by pressing the pedal to the metal. And it makes sense - you save decision time by being consistent!
About 5 years ago Belarus switched to LED traffic lights with clearly visible countdown timers for drivers. I.e. traffic light shows the number of seconds remaining for the green and red signals. Number of accidents went sharply _down_ exactly because drivers could anticipate the light switch.