Ah, that would be something different: http://en.wikipedia.org/wiki/Traffic_signal_preemption

Some of the systems have been hackable/hacked by non-authorized users. There's been stories every so often here on HN.

What I've always wanted - and what might be more mutually beneficial - is a button to cancel the crossing request. E.g. for all those times you press the button, then realise there's enough time to safely cross without the lights changing.

This is actually one of the reasons I never hit the crossing signal in walkable zones: I feel it's rude when I could simply pay a little more attention and cross quickly without taking up others' time.

However, there are lights that do not ever open up to pedestrian crossing unless you hit the button, which irritates me.

A Puffin - http://en.wikipedia.org/wiki/Puffin_crossing may have a near-side detector, that will cancel the demand if you move way from the crossing. i.e. have crossed in the gap.

Certain traffic lights in the UK have something like that. If you flash your lights (at night) as you approach they will change. It's sometimes used where a minor road crosses a major one. At night the lights are configured to stay green for the major road, until either: a) a vehicle is sensed waiting at the minor road's stop line; b) a flash of light detected from the direction of the minor road.

The crossing of the A60 into Rempstone is one such example.

I am a traffic signal engineer. They don't.

They may have a detector (ir-red/mircowave/inductive loop) that detects your approach. At night, as they may be no conflicting demands - the side road will change Green ASAP.

Do they, or did they used to, have light sensors to detect emergency vehicles coming through? Perhaps that was just an urban myth.

Lights in the US have buttons that you can press. But they don't always work. There's one light in Cambrige, MA, that, as far as I could tell, never ever said WALK.

This traffic light is great:

https://www.google.com/maps?ll=41.869753,-87.648017&spn=...

It turns red immediately when you press the button. When I was in college, I would entertain myself between classes by going over, pressing the button just as the upstream light turned green and cars began accelerating, and then not crossing the street.

This, incidentally, is probably why most lights don't change immediately.

Almost all lights here in Christchurch have buttons to request that the lights change, except for a few like https://www.google.com/maps?ll=-43.553027,172.663193&spn... where the button does nothing, and you have to stand on the yellow pad until the lights change, or have a metal bike.

Not everyone understands that you need to keep standing on the pad, or that the bike crossing doesn’t last long enough to walk all the way across.

Just something curious while "walking around" ... https://www.google.com/maps?ll=41.869635,-87.648258&spn=... Banshee from Halo? Hint: cross side to side (following parent link) of street looking to sky

No they don't and no it isn't.

Me too. Does anyone know if kipkay's method actually works?

http://www.youtube.com/watch?v=_1cgE2GaFko

I remember trying out that same code back in highschool, say 5-6 years ago. My friend made fun of me so much for believing it would work. I was disappointed. Not to say it's not true, but it didn't work when I tried it!

All the pedestrian crossing buttons in NYC (I assume other places as well) have been disabled since all the lights are run together by algorithms now.

If only it were true. Most of the country is rushing ruinously toward actuation.

Only a few cities (notably New York, San Francisco, Chicago) believe in pedestrians.

Boulder, CO has taken pedestrian safety to absolutely ridiculous levels: http://www.bouldercolorado.gov/index.php?option=com_content&...

You can know if someone is crossing a street in Boulder from Denver :)

That's what the headline subeditors are paid for

I'd hoped for the same! :D