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Does pressing the pedestrian crossing button actually do anything?

bbc.co.uk

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Re: Does pressing the pedestrian crossing button actually do anything?

#41

Post by samscully »

darklajid wrote: post #11

For me the most interesting piece in that article was the image of a crossing where pedestrians can actually walk _across_ the crossing (like, diagonally) instead of just a single street. Haven't seen those anywhere here and I assume those are actually kind of nasty for car traffic (since .. all directions need to stop). Fascinating :)

They are called scrambles, there are a few in the UK but they are much more common in Japan. As you surmised they only really make sense when there are a large number of pedestrians and vehicular traffic has a low priority.

When I took traffic engineering at university we were taught that crossing layouts like this where pedestrians can move more freely are statistically much safer as drivers drive much more carefully. Another example is Exhibition Road, where the entire road is shared between pedestrians and cars.

http://en.wikipedia.org/wiki/Exhibition_Road

Re: Does pressing the pedestrian crossing button actually do anything?

#42

Post by corobo »

pbhjpbhj wrote: post #26
raverbashing wrote: post #16

"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 b…

> 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. // One may not be able to mathematically ensure optimal operation but you can certainly "make sense" of the requests. Surely you read the inputs and only include the pedestrian crossings in the lighting sequence if the buttons are activated. Unless you're halting the traffic…

Responding to the last part of your comment the sensors are there to cancel the crossing request if the pedestrian crosses early or wanders off elsewhere, to avoid stopping traffic for no reason. The sensors pointed at oncoming traffic can be used to halt traffic if they detect it's moving too quickly for the area. Crossings with the sensors and the don't walk/walk lights on the side closest to you are puffin crossings. The other ones are the older pelican crossings. Infos from http://en.wikipedia.org/wiki/Puffin_crossing

Re: Does pressing the pedestrian crossing button actually do anything?

#43

Post by ethnt »

narcissus wrote: post #37
AshleysBrain wrote: post #31

I think there's a good reason to have buttons that do nothing: it improves usability. Imagine teaching a child how to cross the road. The instructions are: 1) press the button 2) wait for green man 3) cross Now imagine we took away the buttons that do nothing. Now you need two cases, or branching: look for button; if button is present, press it; otherwise just wait - then cross. Obviously this is still trivial but ra…

That's definitely an interesting take, and it triggered a thought I had a long time ago. One thing I've noticed since moving to North America is that children get off the school bus and will essentially just run across the street, including straight in front of the bus, because they know the traffic around them has stopped. I can only imagine that that leads to some sort of subconscious thinking that can only be dang…

It is. Two summers ago, a kid from my school got off a city bus, walked in front of the bus and into the street and was hit by a car and killed.

Re: Does pressing the pedestrian crossing button actually do anything?

#45

Post by corobo »

thom wrote: post #7

There's some next-level traffic light voodoo I often see people attempting in the UK, which is repeatedly pressing the button. I like the idea that it's a democratic process: only when pedestrians outnumber cars will the lights change.

Pressing the button repeatedly until the light changes distracts them from the wait time so it feels faster. Effectively it works, technically it doesn't.

Re: Does pressing the pedestrian crossing button actually do anything?

#46

Post by mikelward »

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.

Re: Does pressing the pedestrian crossing button actually do anything?

#47

Post by coldpie »

JonnieCache wrote: post #10
dspillett wrote: post #6

In York (UK) it is a mixed bag. There are a couple of simple pedestrian crossings near my home where the lights never change without a press and change very quickly once requested. At junctions it is more complex and seems to vary: some definitely have their sequence altered by specific pedestrian requests, some definitely seem not to. I've not noted if any vary by time of day, as some people report.

Any crossing near a school will generally change very quickly after a button press, but only during the school-run hours. Knowing which these are can noticeably accelerate ones journey to and from work.

There's a light near my apartment that takes about 4 full minutes to change (it's a small-road-onto-big-road intersection), at all hours of the day. However, the walk light changes the light instantly.

I leave for work around 6 each morning, when there's nearly no one else on the roads. Since it's so frustrating to watch an empty road for four minutes, I have actually gotten out of my car, hit the button, and gotten back into my car to accelerate the light change.

Re: Does pressing the pedestrian crossing button actually do anything?

#48

Post by thaumasiotes »

paulbennett wrote: post #32
Jacqued wrote: post #25

The most fascinating part of this for me is that people _actually_ pay attention to the green and red men at crossings, and even to crossings at all. I mean, sure, where I live children or older people who can't walk very fast wait for the green man but most regular folks just go and cross where and when they please. I believe in Paris all of these are entirely automatic ; though there are buttons that are here to he…

This is fine on quiet roads, but doesn't work in busy cities. If you tried to cross the road on my walk to and from work without waiting for the traffic to be stopped you'd get hit very quickly! edit: perhaps you live in Paris? In which case I don't envy you having to cross the roads there!

> This is fine on quiet roads, but doesn't work in busy cities.

I guess I can claim to have lived in Shanghai for a span of (not many) years, and I have to dispute this. People will just walk out into the middle of a busy street, making lane-by-lane progress much like Frogger if they have to. They do it because the only real alternative is not crossing the street at all. When I was working at an international school here, it was common (and, in my view, completely justified) for new arrivals to want help crossing the street. But the fatality rate is quite low. ;)

Re: Does pressing the pedestrian crossing button actually do anything?

#49

Post by e40 »

mikelward wrote: post #46

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…

It seems traffic planners don't care about pedestrians.

You got that right. I walk 4+ miles/day on city streets and I've noticed a steady erosion of rules designed to make pedestrian life safer and easier. What you mentioned above and this:

In addition to lights which are timed to not give a "go" signal to pedestrians unless they push the button, I've run across one that will make you wait until the next cycle unless you press it before the current cycle begins. That is, I push it a second after I would have gotten the "go" signal and I have to wait an entire cycle before it actually tells me to walk. The effect of this? I go anyway, but because the cycle without pedestrians is shorted this is quite dangerous.

Here's another trending in my city: buildings which sit directly on streets with parking lots that empty onto streets having their own lights, have separate lights for pedestrians to regulate them while on the sidewalk. So, you're walking down the sidewalk, no where near an intersection and a car comes out of a "driveway" at 20+ miles/hour. Freaked me out the first time this happened. I could have easily been killed as the car was just a few feet from me.

My guess: some city planner was paid off to allow this completely unsafe situation.

Re: Does pressing the pedestrian crossing button actually do anything?

#50

Post by randlet »

coldpie wrote: post #47
JonnieCache wrote: post #10

Earlier quoted context omitted.

Any crossing near a school will generally change very quickly after a button press, but only during the school-run hours. Knowing which these are can noticeably accelerate ones journey to and from work.

There's a light near my apartment that takes about 4 full minutes to change (it's a small-road-onto-big-road intersection), at all hours of the day. However, the walk light changes the light instantly. I leave for work around 6 each morning, when there's nearly no one else on the roads. Since it's so frustrating to watch an empty road for four minutes, I have actually gotten out of my car, hit the button, and gotten…

Probably easier to just treat it like a stop sign rather than actually getting out of your car if there's no other traffic.
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