Interesting Links for 05-09-2013

[andrewducker]

• Does pressing the pedestrian crossing button actually do anything?
  (tags: technology roads )
• The top code comment here is a classic
  (tags: programming funny )
• Fascinating discussion of accents, how people change them, and the effect they have.
  (tags: speech accents language )
• Using harsh verbal discipline with teens is counterproductive and

Comments

Does pressing the pedestrian crossing button actually do anything?

[cartesiandaemon]

People always seem to make this more complicated than it needs to be. It seems that nowadays:

1. Most vehicle junction controlling traffic lights automatically display a walk sign if the natural cycle for cars gives a red light in that direction. Anything else would be ridiculous -- not unlikely, but I think people would notice.
2. Most stand-alone crossings have a button that activates them. If you're standing near one, it doesn't keep changing automatically.
3. Other junctions are less obvious and may or may not change automatically.

The default situation seems fairly unexceptional to me: sometimes you need to press the button, and as long as you never the button and then don't get a walk sign, there seems to be no harm. After all, someone might reprogram them again. If you NEVER need to press the button, then sure, you can remove the button

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

[naath]

I remember having an odd discussion with my mother once where she alleged that because pressing the button does not *instantly* turn the man green that it "clearly" therefore does nothing. This was at a junction where (from observing it) I believe the truth is that there is a sequence Traffic A/Traffic B/Traffic C/Pedestrians but that if the button has not been pressed the Pedestrians phase is skipped. In general where the button needs pressing it rarely instantly turns the man green IME there is generally a minimum time for which the man is red (and the traffic light green) between green man cycles (observed on busy pedestrian crossings).

In Cambridge there are some places where the button-pushing is complicated by there being bicycle-sensing loops; which auto-press the button for you if you approach by bike.

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

[pigwotflies]

On some crossings (not junction crossings) pressing the button instantly turns the traffic light to amber.

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

[naath]

Yes, although even then there is usually a minimum "red man" time between green men (if you press the button again the moment the man goes red the traffic still gets a few minutes green).

[theweaselking]

Often when a big road crosses a small one, the lights stay always-green and always-walk on the big road, and the big road only goes red when someone wants to use the small road.

There's sensors to detect cars, and pedestrians push the button. As long as the big road had been green long enough, triggering either the sensor or the button immediately starts the cycle. After the cycle ends, the big road goes green again and stays that way for a minimum time before the sensors go live again.

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

[cartesiandaemon]

If I saw lights like that, I'd want to test it, but then, I'm me... I'm honestly surprised that any lights immediately change: it seems to be true, but I'm used to the idea that you usually have to wait a minute. Maybe if I was less self-deprecating, I'd expect them to change immediately.

In Cambridge there are some places where the button-pushing is complicated by there being bicycle-sensing loops;

Ah! That's a good idea, but I didn't realise it existed.

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

[naath]

if you go along Fair Street and want to cross Maids Causeway onto the common that crossing senses bikes

[threegoldfish]

The first lighted intersection from my house is timed to primarily let the major road traffic through. The side street light is triggered if someone sits in the left turn lanes long enough. The length of the side street signal depends on how much traffic goes over the left turn signal sensor *or* if the walk button is pressed. If the walk button is pressed, the length of the side street signal is at its longest. It also will turn the light even if there's no cars waiting to turn left. If the walk button is not pressed, the side street signal will be quite short, not really enough time to cross the street and it doesn't automatically give you a walk signal. It's not something that's super obvious and definitely not immediate. I've only got the pattern down because I used to wait for the bus at that light. I can see why people would think that it's not effective if they didn't watch the changes multiple times.

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

[danieldwilliam]

There are a four junctions on my way to and from work where the flow of traffic is only one way or there are no junctions - just a pedestrian crossing - and the pedestrian crossing only works when the button is pressed. They have WAIT signs that illuminate when the button is pressed. One of my pet irritations is when people don’t press the button and then stand in the way of the button and then look baffled / cross when someone asks them to move so that they can press the button.

If no one is crossing the street then the traffic just flows. The one nearest my house has a quite a quick cycle between pressing the button and the lights changing. It’s quite a busy pedestrian crossing point (so busy in fact that I credit the use of a large electronic billboard next to it with Labour winning Edinburgh South at the last Westminster General Election) so it makes sense for the lights to be on a quick cycle. Especially as during the rush hour the traffic is usually stop start anyway.