h a l f b a k e r y
Recalculations place it at 0.4999.
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Have you ever wondered how the timing
on pedestrian crossings is set up? The
answer is that there is no method. It's up
to the individual planner designing the
crossing to set the timing to what they
feel is appropriate. This will not do.
What the world desperately needs is a
a benchmark to calibrate all
crossings. What we need is the "Industry
Standard Granny." She is wheeled out of
safe storage every year and is used to
callibrate a fleet of aging dotty old
women so that they all walk at the same
This horde is then used to test
pedestrian crossings everywhere to make
sure that people have just enough time
to cross between the time the crossing
signal starts flashing and the moment
the traffic mows them down.
Possible future development:
European Standard Granny: The original
American Standard Granny: Moves slower
due to excessive hamburger
Russian Standard Babushka: Wends her
way across the road due to excessive
Standard for blind pedestrian crossings
Under development for ISO. [pottedstu, Oct 12 2001, last modified Oct 05 2004]
The first link I found, there's probably loads more if anyone is interested. [stupop, Oct 12 2001, last modified Oct 05 2004]
||<pre-empt>Industry Standard Afghani</pre-empt>
||Sure, you can slap an "ISO Certified" sticker on the Granny, but the inevitable question with weights and standards will still arise: who calibrates the ISO Granny? She can't be self-calibrating (since she might slow down or speed up while in storage). So you'll have to have something to check her against. . .
oscillation frequency of the ISO flocking road cones??
//aside: picturing a Monty Python-esque calibration procedure of pacing the crew of grannies to the ISO Granny//
||Perhaps she could be calibrated against the distance from one curb to the other.
||If all grannies started to walk at the same speed they'd start to 'bunch', which would inevitably lead to them starting to chat, which in turn would make them stop. I can see this idea bringing the whole granny network to a standstill. Large granny clusters would clog up cities standing talking about the price of coal, and kids these days..
||No, no, no. Enough with the flocking, already. Save it for the 'cones.
||[quarterbaker]: *Exactly* the image I had in my head when I was writing this.
[beauxeault]: That has a weird self referential quality that I really like. More to the point, it actually works. Sort of.
[GTR]: Far too logical.
[stupop], [blissmiss]: You would have to be careful to make them cross one at a time to keep them accurate. Don't know how to avoid the clumping in city centres though. Hang on a mo - that happens anyway.
||It depends on the width of the carriageway. Normally it's between approximately 6 & 22 seconds, although many have a presence detector and are variable. When these things are designed (in London) a computer program called LINSIG works out the timings. I believe it calculates ped. crossing times on the basis of a minimum walking speed of 1.2 m/s. I don't know how that figure was arrived at but it sounds a bit fast for the ISG.
||[st3f] You get my croissant, just for the mental image of some Clara Peller-esque blue hair in a wind tunnel, with white coated, clipboard toting lab techs outside, observing her.
||// in New York: it is simply against the law here to run people down //
||PeterSealy, is that like in California, where don't they have some kind of a pedestrian right-of-way law, where you can step into the street wherever you like and cars have to stop?
||I think we've overlooked one problem so far here. Where shall we store ISO Granny, and how long will she keep?
||The storage problem is easy. ISO Granny should live in a log cabin in the middle of the woods, somewhere in Florida. But we will have to guard her against the non-compliance wolf. Every once in awhile Little Redshift Riding Hood can come along and calibrate her against the speed of light.
||1 Granny = exactly .25 m /s.