Talk:1175: Moving Sidewalks

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Revision as of 16:30, 19 February 2013 by (talk)
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I'm not quite sure what the joke here is supposed to be. Many have tried to develop variable speed walkways, as one can see in patents. There was even a pair of these that were installed circa Y2K in the Paris subway (Châtelet-Les-Halles, IIRC), which is renowned for its long passageways. It is AFAIK no longer in service, I don't know why. When I saw it an attendant was present to watch over for making sure that users wouln't fall. This contraption is way more complicated than standard rubber-belt conveyors with its meshing steps. -- 15:59, 18 February 2013 (UTC)

I know what I'm building this weekend... 06:22, 18 February 2013 (UTC)

I just wonder if it is possible to remove these stupid posts and the panel on top of them from my treadmill without breaking it... -- (talk) (please sign your comments with ~~~~)

Isn't "of" suppose to be "off" in the title text? -- (talk) (please sign your comments with ~~~~)

Do anybody know examples of such belts. The ones I recall has all one-speed-only Spongebog (talk) 10:43, 18 February 2013 (UTC)

At Toronto Airport they have double speed moving sidewalks, that accelerate by stretching the panels. --Johnsmith (talk) 08:43, 19 February 2013 (UTC)

I was under the impression (from the alt-text), that they would take the belts inward traveling faster until they hi-five. Then, as they sped away, they would change sides and repeat the process. 10:56, 18 February 2013 (UTC)

I don't see why they are positioned as they are. If they were taking the belts inward, they would take advantage of the momentum imparted by the belts and be going much faster than their stride would normally take them. The way they are positioned, they would have to be running to just catch up to each other in the middle. 11:06, 18 February 2013 (UTC)

This is surely the point. They have to run faster as they get closer. 12:00, 18 February 2013 (UTC)
Has the picture changed? Now it seems as if they where going faster to the middle. --Johnsmith (talk) 08:48, 19 February 2013 (UTC)

There doesn't appear to be any 'trick' to this one. Like the commenter above, I initially thought they were being taken towards each other by the conveyers. I thought the joke was that they would be accelerated to a ridiculous speed which would make it impossible to high five without obliterating each other, but the alt text didn't indicate anything like this and I looked again and realised I had read way too much into it. It's probably most sensible to interpret the speed multiples as relating to the first belts, not the last one you were on. This makes the difference between the '5x' belts going at 5x the speed of the outer ones, instead of 100x if each was the specified multiple of the last. If this alternative situation were the case, the outer belts would have to be going very slowly (of the order of 0.1m/s) for them to ever be able to high five. 12:00, 18 February 2013 (UTC)

The appears reminiscent of Improv Everywhere's prank, "High-Five Escalator" JamesCurran (talk)

I'm sure I would fall over trying to use this one. -- 14:09, 18 February 2013 (UTC)

Randall updated the comic, explaining that he meant to draw the arrows going the way Cueball and Megan are facing, not opposite. I'd change the wiki, but I don't get it now. :) Zpletan (talk)

The Comic has been changed: "Oops! I originally put up a version with backward sidewalk arrows. I should know better than to edit and post comics while sleep-deprived. Sorry!" 14:28, 18 February 2013 (UTC)

I don't think they're going a multiple of the previous belt, but a multiple of base speed. Just my 2 cents :) Also, I think the belts are moving toward each other to get the ultimate "high five" in terms of velocity of the impact. -- (talk) (please sign your comments with ~~~~)

I don't see why anyone would think the "5x speed" etc would mean 5 times the previous tile. Seems obvious to me that the first tile is moving at some speed, the second tile is moving twice that base speed, the third moving 3x that base, etc. So when the pass each other their moving at 10x the base speed. Assuming the base speed is something reasonable, something near a typical walking speed, the high five would take place at a speed similar to if they were just sprinting past each other. Hardly a "ridiculous speed which would make it impossible to high five without obliterating each other." 16:58, 18 February 2013 (UTC)

Does anyone think this may be a reference to "The Caves of Steel" a novel by Isaac Asimov? As I recall there was a global system of moving belts of various speeds that were used for transportation.

That's what I thought of immediately. 19:17, 18 February 2013 (UTC)
Or Heinlein's "The Roads Must Roll". 19:41, 18 February 2013 (UTC)
Also Clarke's The City and the Stars, for the Big Three trifecta. But in those stories, the different-speed belts were arranged in parallel, like lanes of a highway, rather than in series. So you'd accelerate by stepping sideways from belt to belt.
Wwoods (talk) 20:30, 18 February 2013 (UTC)

Seriously, they're playing a game of Robo Rally talk

I would love to see this sidewalk placed in a Bison habitat. 05:04, 19 February 2013 (UTC)

Is it just me - or was this comic fixed after it was initially uploaded? I could've sworn the original had either the arrows backwards or the people on the wrong sides - They would've been fighting the sidewalk. 09:59, 19 February 2013 (UTC)

As an edit to this, I was correct. This is a mirror of the comic on Gizmodo, showing the error. -- ‎ (talk) (please sign your comments with ~~~~)
And it seems that when fixing it, Randall changed all the arrows, rather than moving the people. JamesCurran (talk)

I wonder, what is the pace of the centerbelt? Is it 5x, 6x or maybe about 5x where that belt start, accelerating to 7x (or even more?) at the high five location and then slowing down till about 5x at the end? 16:30, 19 February 2013 (UTC)