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Does pressing the pedestrian crossing button actually do anything?

bbc.co.uk

21–30 of 68 posts

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

#22

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 :)

That picture is of Oxford Circus, one of the busiest intersections in the UK. There are very few crossings similar to that one here.

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

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

#23

Earlier quoted context omitted.

I used to do this. It's because of the confusing presence of the AC button. The UI has made clear to you that there are multiple levels of cancellation, one can in fact "really cancel." We know full well that there is some overcomplex internal state to the device, and rather than reading the manual for a calculator (honestly) we hammer the cancel button a few times, just to make sure.

I hadn't thought of that, but it makes sense. A quick search reveals that some calculators have an AC button (clear everything) and a C button (clear last entry), while others have C (clear everything) and CE (clear last entry). Definitely confusing.

I'd forgotten about CE. Even worse.

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

#24

Pretty sure it alerts the system that there are pedestrians waiting to cross, otherwise why stop traffic if no-one is there?

So, do you think the quotes from people running the system who say that is not the case are lying for some reason? Or do you think you know more about how their system works than they do?

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

#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 help the visually impaired by telling them where they are and if they can cross safely.

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

#26

"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 for some ulterior flow management need.

As for non-interrupt raising buttons - the "WAIT" light should show to indicate the button isn't required to be pressed.

Lastly, some crossings in the UK have what appear to be cameras (I assumed some form of wide angle IR sensor) facing the pedestrians. I assumed these could provide input as to density of pedestrians waiting in order to balance flow of pedestrians vs. road traffic. Anyone know certainly what they're for?

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

#28
post #4

Not nearly as annoying as lift/elevator buttons.

We have our lift buttons on the outside. You choose your floor, and are directed to one of the 6 lifts available. This seems to confuse every visitor to the building, who will walk into the first open lift (that will have opened for someone else). They spend 5 seconds looking for the buttons, the door closes, and they're stuck going to a floor they never wanted.

However, as the buttons are on the outside, the designers clearly thought they would aid things where a large group all want to go to the same floor. Press the special people button, enter how many of you there are, and the lift system will optimise to ensure it doesn't needlessly stop at interim floors if you have filled that lift to capacity, or send you a lift already filled that wouldn't fit your group in.

So the trick is to say, even if you are a single rider (lifter?), that you are a party of 14, guaranteeing your lift won't stop at any other floor on the way to yours. An 'express mode', if you will.

Problem is, everyone working in the building seems to know this trick, and it does not scale. Whilst it might make the time in the lift shorter, I notice that the wait time for a lift appears longer (from observing those going to my floor who have done the trick before I then select the same floor normally). The real trick then is to use the lifts as they were intended. The irony is that all these 'super busy' types who are slowing everyone up are simply slowing themselves up too.

Then again, who was expecting a building full of lawyers and traders to behave like good citizens?

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

#29

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.

Well this is a rare treat, a fellow York dweller, greetings!

What? 3 of us? Heavens!

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

#30

Pretty sure it alerts the system that there are pedestrians waiting to cross, otherwise why stop traffic if no-one is there?

So, do you think the quotes from people running the system who say that is not the case are lying for some reason? Or do you think you know more about how their system works than they do?

The question still stands. Why interrupt the road traffic if there are no pedestrians waiting? It's possible to answer that "for flow control" but I'd warrant that's not an effective proposition for the majority of junctions.

I didn't see this specific question addressed in the OP so it's quite possible it was simply glossed over to provide a simplified answer or the reporter worked around it to make it easier to express the sequence.

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