I've experienced plenty of beg buttons that don't do anything other than activate the crossing light when that direction next goes green for cars. But also plenty where pressing the button takes immediate steps for the pedestrian: if the direction is already green for cars, the walk sign is turned on; otherwise, the current cycle ends and any intermediate cycles proceed with minimum duration; non-dominant directions will have longer minimum cycle time if the pedestrian button has been pressed.
In my experience, if the intersection processes car traffic dynamically, it will also process pedestrian traffic dynamically, and generally favor pedestrians. If the intersection has static timing, it's not going to do anything different for pedestrians. I recall driving in Milwaukee near UWM two decades ago, every morning I could count on the lights showing exactly the same thing at the same time. If I left my apartment at the same time, I'd get the same sequence of missed or made lights. Most other places I've driven had car sensors (usually loops in the pavement, but cameras are cheaper and less maintenance now), so there's no schedule to be learned, although the behavior is predictable if you learn the cycles and observe the stimuli. (Although, sometimes sensors are broken or miswired; there was an intersection near one of my employers where the cyclist button was connected as an left turn lane occupancy sensor; resulting in consistently wrong behavior. it's also not uncommon for a disabled vehicle to be located above a loop, or sometimes a construction / utility vehicle to be parked above a loop; some control systems can adapt and filter that out, but many don't.)
Huh? I've never seen this. If the drivers get a green turn arrow the pedestrians get a don't-walk. However, I see (and have been one) pedestrians who understand the light going anyway across the part of the road that's facing a red, treating it as two separate crossings. While this is not a problem I have also seen pedestrians going the other way start to cross when the oncoming pedestrians start--and they may be crossing against the green arrow. Same as you sometimes see drivers go because the lane next to them went but it was actually on a different traffic control.
As for the pedestrian hitting the button--I have never seen the button alter the sequence of the lights. The button does two things: Cause the light to cycle (in case it's sensor controlled and won't cycle if nobody comes along) and ensuring the cycle time is long enough for a pedestrian to cross. I've also seen hitting the button causing the button to indicate the status of the light (for the blind.)
I am not a traffic flow engineer, but I have experienced what you describe in regard to the walk button behavior in many places in western Washington, US. I always reckoned that they were using a simple model in which a button press would cause the "WALK" signal to always be fired at the corresponding light configuration at the _next_ cycle start. This is most likely a safety consideration because, as you noted, there may not be enough time to safely cross.
In some complex intersections I've noticed that the 'cycle start' doesn't necessarily line up with the corresponding configuration for the walk button which was pressed. This may result in having to wait nearly two complete cycles for the walk signal in the worst case (pressing the last configuration's walk button immediately after the cycle start). The resulting behavior could be considered a bug, or perhaps just more consideration payed to vehicle traffic. But it is certainly frustrating as the pedestrian.
At many intersections I cross now the signals are automatic with the traffic flow. Most of them also contain a countdown timer indicating the number of seconds until the light changes. It seems that this behavior would be a good tradeoff for pedestrian efficiency and safety. However it comes with a bit of trust from the gov, that you know you can't walk across 5 lanes in 2 seconds.
The crosswalk buttons around me are a frustrating mess. I used to live on a street where the intersection to the main road had a sensor that either couldn't detect my car or just didn't work at all. The only way to get a green light was to have someone get out and hit the crosswalk button, which quickly changes the flow of car traffic.
Meanwhile, I have not seen this behavior anywhere else in the city where it would make sense. Instead, we have almost all crosswalk buttons that do nothing, a few that turn on a light so drivers can know you want to cross (they won't stop, but they'll know), and a few where you will never have a walk signal unless you hit the button, but the light timing does not change. I have watched plenty of tourists helplessly trapped at an intersection not knowing why it never changes.
The pedestrian button thing varies wildly in the US.
I have several pedestrian crossings where the if you as a pedestrian don't hit the button... you'll never get a signal to cross and the traffic is not impacted. But if you do push it, it does give you time to cross and holds the cars longer.
One place traffic never stops, until you hit the pedestrian crossing button, and then they have to stop.
On the other hand in some pedestrian dense / slow traffic areas I know the buttons don't do anything as the pedestrian crossing lights just change with the lights, but only during high pedestrian traffic times.
I think it has more to do with policy and how you want to time your lighting systems and it varies wildly in the US
Often in Australia, pressing the button makes the pedestrian light go green. But it has no effect on signal order (it goes green when cars traveling in the same direction get a green light).
What's the point of making us press a button in this case? Why not give pedestrians a green light automatically?
Even more obnoxious are intersections where the pedestrian light times out from green to red, but cars still have a green light. You can press the pedestrian crossing button and get a second walk cycle.
Again, why not just make the first walk sequence longer?
It seems traffic planners don't care about pedestrians.
In many places in the US, pedestrian buttons don't change the lights, certainly not within 1-3 min, if it's a busy or major intersection with lots of vehicle traffic. Also, the controller behavior can change during the day/night depending on traffic volume, or maybe time of day. One time I counted it took the lights 7 minutes to change at a three-lane intersection late at night, even though there were no cars.
At some low traffic crossings, the lights are programmed to tend to be green in the more trafficed direction, but will start to change immediately if there is an indication of demand in the other direction -- through a pedestrian button on a detector loop in the road surface. When there's higher traffic, they do more of the traditional cadence, but pressing the pedestrian button ensures the cycle will be long enough to cross the street.
A common and smart design I've noticed here (Canada), is that at moderately busy pedestrian intersections the walk signal will turn on a couple seconds before the traffic light turns green. This means when people first start walking, all directions have a red light, and then it's also much more obvious to traffic that people are crossing because they're already on the street while the cars are still stopped.
I think on some intersections pressing the button will make this delay longer, but it's hard to tell from casual observation. Also, traffic light timings are set by the municipality, so it can vary by city and depending on the age of the intersection.
The most dangerous intersections I find are on the multi-lane suburban arterial roads. Pedestrians are less common (than in neighborhoods or downtown) so drivers generally aren't watching for them as much. You really have to be careful with cars turning right on a red - even if there's a walk signal - because they're looking to their left for traffic to see if it's clear for them to go, and not for people coming the right about to walk in front of them.
Not universally true. I have seem some crossings in Texas and elsewhere where the light is solely for pedestrian crossing and will change (after a short delay) on command. On intersections that are sensor-controlled they will also change the light if there is no cross traffic to change it for you.
That said, on intersections where the lights are purely timed or where there are always cars waiting in both directions, it pretty much is a "beg button". At that point, there is no way to allow on-demand pedestrian crossing without making the roads useless to cars. In fact, some places like NYC don't even have buttons because they are pointless and possibly counterproductive.
Does the Pedestrian Walk signal come on if you _don't_ push the button, I mean, _ever_ - if it doesn't, and then comes on immediately after pushing the button - you've found a working button. It only takes one cycle through the vehicle traffic lights (and zero, obviously, in a pedestrian controlled intersection) to determine which is which.
It makes sense to control pedestrian traffic in some intersections, but it just seems like they're not even trying to optimize pedestrian throughput. What makes the lack of feedback for crossing buttons worse is the fact that many of them are so conservative about letting you cross that you question if they are working. I encounter a lot that will refuse to let you cross if the light is already green, even if there is still plenty of time left. Unfortunately, lowering pedestrian accidents looks great, while saving pedestrian time is hard to measure.
"The short answer is - it depends. At a standalone pedestrian crossing, unconnected to a junction, the button will turn a traffic light red
At a junction it is more complicated."
That's all you need to know.
I've been to places where the 1st case applies. Press the button, the car signal turns yellow immediately (light traffic and light pedestrian traffic)
At a crossing, let's see, you got there and you pressed the button, then another person came and pressed the button to cross the other street (meaning, traffic where you want to cross)
No system can make sense of these requests, and the traffic has to flow. Makes sense to just go through the movements and ignore the buttons.
At least in NYC, the pedestrian crossing buttons have no effect on the traffic lights. They computerized the traffic grid and them pesky pedestrians screw up the flow. So you can push all you want, but it wont speed things up.
Cities are more and more doing this (what you specified for pedestrian lights outside the US). My problem: there's a very large intersection that I walk through daily that changed to "only allow walk when the button is pushed" and 9 times out of 10 when I walk up to it and push the button when it normally would have been set to "walk", nothing happens. Then, the next traffic cycle I get the "walk" light. However, I've also noticed that from the time I push the button until when the cross traffic starts, 90% of the time I would have had time to walk across the street. So, I've started ignoring the button and just walking when "the time is right." In this case, it has made me less safe. Twice in a few months I've been caught in the middle of the street when the light turns.
I realize that in this case, the walk portion is probably just not tuned properly, but I wonder how often that happens.
In certain especially pedestrian unfriendly places I've lived (orange county area), the buttons really do give pedestrians a lower status. First, you don't get the walk sign if the button wasn't pressed before the light changed, even when the light is long enough for the pedestrian cycle. Second, you must press the button before the light changes, or you don't get the light. Third, the pedestrian light turns red far, far earlier than necessary (like, the light will stay green for 90 seconds after the pedestrian signal turns red).
I have never seen an intersection where beg buttons favor pedestrians and not drivers, because beg buttons give engineers the latitude to establish red crosswalks unless requested. So help you if you arrive just in time to miss your activation cycle and have to wait a full light cycle for the crosswalk.
Intersections where cars have to pass detectors (induction coils in the ground) to get a green light exist. Same principle: only switch the lights if there is demand for it, with a default oriented at the most likely demand.
The pedestrian-default at least around here is implemented by making entire zones slow-driving and pedestrian-priority, not on single intersections. If cars are allowed higher speeds, it IMHO makes sense to have pedestrians push the button and wait a few seconds, since they can do that easier and more efficient.
Crosswalk buttons do work in some cases, where the lights are usually open for cars but if a pedestrian comes, presses the button then it goes red
Now, to expect that a 4-way intersection will have any way of obeying the buttons (of that crossing and of all the other pedestrians in all the other crossings) is just laughable
I have yet to see a 'working' crosswalk button in my nearest (non-NYC) metropolis. This would be because every light-controlled intersection I traverse on foot is on a programmed loop. Reliably, the crosswalk lights go to "walk" a second before the parallel street goes green. This happens five seconds after the perpendicular direction goes all red.
That's not to say that sensor-controlled intersections which take the crosswalk button into consideration do not exist- there are far too many intersections which I haven't the time nor the inclination to tour.
Ultimately, my point is this: simply because all the media on placebo buttons dwells on New York City does not mean similar devices don't exist elsewhere. I bet here, folks just don't care; they press a button and eventually get through a light.
In my experience, if the intersection processes car traffic dynamically, it will also process pedestrian traffic dynamically, and generally favor pedestrians. If the intersection has static timing, it's not going to do anything different for pedestrians. I recall driving in Milwaukee near UWM two decades ago, every morning I could count on the lights showing exactly the same thing at the same time. If I left my apartment at the same time, I'd get the same sequence of missed or made lights. Most other places I've driven had car sensors (usually loops in the pavement, but cameras are cheaper and less maintenance now), so there's no schedule to be learned, although the behavior is predictable if you learn the cycles and observe the stimuli. (Although, sometimes sensors are broken or miswired; there was an intersection near one of my employers where the cyclist button was connected as an left turn lane occupancy sensor; resulting in consistently wrong behavior. it's also not uncommon for a disabled vehicle to be located above a loop, or sometimes a construction / utility vehicle to be parked above a loop; some control systems can adapt and filter that out, but many don't.)
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