[mherdeg]

Heinlein's "The Roads Must Roll" posits a network of very fast, very long moving walkways which could be used for mass transit (you'd ramp up speed on slower ones then hop over to a fast one). Wikipedia says that moving walkways had been in sf for decades by that point, but Heinlein also almost incidentally invents the Segway in the story -- just a little treat.

I love peoplemovers (like the Hong Kong Central-Mid Level escalators and the delightfully bouncy SFO walkways) and always wondered what would have to be different for us to get super-fast ones for transit.

In Boston, IMO they would be at least as good as the Green Line :)

[mpsprd]

Asimov introduced me to this concept in I robot.

In his version there were multiple levels of speed for entry/exit of transit so the main highways were going really fast.

IIRC it required some dexterity to use and sounded a bit dangerous...

[adolph]

Requires dexterity and seems somewhat dangerous? Meet the Paternoster elevator:

https://en.wikipedia.org/wiki/Paternoster_lift

[KineticLensman]

I used to regularly use these at the Uni of Leeds in the Roger Stevens lecture theatre building. Never saw an accident. Freshers were told that they turned upside down when going over the top but in fact they just slid sideways to the next shaft (we used to ride over the top sometimes to beat a queue going down) but they could apparently jam if too many people tried it so it was frowned upon by the porters.

[HideousKojima]

Got to ride one of those in the Bat'a building in Zlin, Czech Republic. Supposedly that version had some sort of safety mechanism to keep you from crushing your arm off if you didn't have it tucked inside, but I didn't dare test it. We called it a "Mario elevator" due to the obvious similarities with the elevators in the original Super Mario Bros.

[alluro2]

"Their overall rate of accidents is estimated as 30 times higher than conventional elevators. A representative of the Union of Technical Inspection Associations stated that Germany saw an average of one death per year due to paternosters..."

Wow - those were definitely different times in terms of acceptable risks in various aspects of life.

Modern times obviously improved a lot of it, but if you're at least a bit cynical, you also have to wonder how much, due to those measures, people are "prevented" from having to build out their awareness of surroundings, dexterity and overall "aptitude for life".

[mouse_]

One death per year is literally nothing compared to cars.

[chefandy]

I imagine if you compared the number of injuries to the distance travelled, or even trips taken, cars would come out way ahead.

[timeon]

In some instances (like suburbs) need for distance is increased by cars.

[palemoonale]

Of course someone had to bring up cars. You know how many people get striken by reckless cyclists?

[timeon]

Barely any relative to car accidents.

What is your point?

[pmontra]

More or less people than the ones that get striken by reckless car drivers?

[chefandy]

Feel free to show some comparable statistics.

[matheusmoreira]

It's like they took an obstacle from some Mega Man stage and implemented it in real life.

[user982]

Are you sure it wasn't The Caves of Steel?

[mpsprd]

I think you're right, I misremembered the source. Reading online it's called the "robot series" and Asimov says he borrowed it from Heinlein.

[bee_rider]

As long as there aren’t any gaps, I guess it is just the difference in the belt speeds that you care about. Also the wind.

[dev_slash_null]

You also have to consider what happens if a 60mph belt breaks/halts while people are on it.

[corlinpalmer]

Moving walkways have a big power efficiency problem over a distance. While you can make a train track longer without decreasing the efficiency of the train, a moving walkway has to move that whole walkway. Can you imagine the friction on a 10 mile long moving walkway? You would need massive motors just to budge it.

[ricardobeat]

If, like in the design seen here, the slide movement and propulsion is decoupled, and motors add impulse to the platforms at constant intervals, doesn't sound like that would be a problem. These wood platforms must have weighed tons by the way.

[anothernewdude]

Doesn't need to be one big continuous walkway.

[chefandy]

The moving walkways in some airports, for example, have multiple moving sections and work just fine.

[thereisnospork]

Required power should essentially be a constant per unit length, can easily have 1 motor per kilometer or city-block.

And for my dumb idea of the day: 'just' use solar panels as the walking surface as use that to power the slidewalk.

[Joeri]

So, linked hoverboards as walkway segments with a solar cell surface controlled by a mesh network?

[cybrox]

Solar friggin sidewalks!

[_kidlike]

mmmm yes! let's make our cities even hotter

[cpill]

could hoover like a monorail?

[twelvechairs]

Mid level escalators have a very definite purpose as people wouldn't walk up that steep slope before.

Moving walkways along flat surfaces though? Its very hard to make them attractive. Most people like to walk a little, certainly we are built for it genetically and most people don't walk as much as they should in any case. In terms of mass transit nobody has ever got the safety and space issues to work. They only really have tended to work in airports where there are sometimes very large distances to traverse, and you need an (actually pretty slow moving for safety) solution for the elderly etc. who aren't as mobile. Even at an airport unless distances are massive and people have giant luggage most will prefer to walk, or only take the moving walkway for novelty value.

[iainmerrick]

In airports I’ve been to, most people walk on the moving walkways. Twice as fast!

[mcmoor]

I've been taught that that's what walkways are for. To walk twice as fast!

[soperj]

People would walk more if they could get to where they were going fast. If you could walk to the store as quickly as you could drive, why would you get in the car? No traffic jams on a sidewalk.

[chefandy]

It’s certainly true in NYC. Even if it takes a touch longer than taking the subway, lots of folks walk. If the infrastructure supports it, people will use it.

[palemoonale]

To transport their just-bought stuff?

[chefandy]

In dense cities? Yes. You don’t need a car to transport a load of groceries if there’s a grocery store on the 20 minute walk home from work. For larger trips, backpacks, rolling folding grocery carts, or even wagons do nearly everything a car can do. I used a car sharing service, as needed, for most of my adult life. Having moved to a city with shit for public transit, I miss the hell out of that.

[fragmede]

I think the concept of not doing a months worth of grocery shopping for a family of four at a time is w what's foreign. going to the store for pasta and eggs and toast and nothing more is a waste of a grocery trip in some people's eyes. Those people love to shop at Costco and Sam's, and have a SUV's worth of groceries each time they do a trip. It's not a wrong way to live, but if that's how you live, not driving a vehicle with enough cargo space to hold a large body around means it doesn't make sense how you'd get any groceries. Doing that large a run is exhausting, so you don't do it very often, which means when you do go, you have to do a huge run which makes it suck. Smaller more frequent trips is shorter and mute frequent, which has its own, different problems.

[chefandy]

Agreed. Even then, I used to take the subway to a regional big box wholesale club to grab stuff that made sense. If I lived nearer to a Costco, I’d take advantage of their fantastic sustainable fish program. Lot’s of good quality stuff has a totally worthwhile price point at those places. There’s a lot of room for different approaches, even in dense cities. Most people in cities don’t even have room to store that much stuff. I never did, and I didn’t miss it.

[strken]

I'd never heard of the mid-level escalators before. Apparently they're on a slope with an elevation gain of 135m over 800m, which is pretty serious for someone who's out to do some shopping: https://en.m.wikipedia.org/wiki/Central%E2%80%93Mid-Levels_e...

[Andrex]

Getting out and walking was frequently as good as the Green Line when I lived there...

[occams_chainsaw]

Same for me just in October for some stretches

[euroderf]

In Heinlein's books, do the rolling roads come before or after the establishment of American theocracy ?

Asking for a friend.

[dsq]

Just from my rusty memory, the roads were after the Crazy Years and before the Prophet. So yes, before the theocracy. EDIT: I found a link to the chart.

http://templetongate.net/graphics/literature/fhchartlarge.gi...

[riffraff]

I seem to recall this is also a thing in "the city and the stars" by Clarke (1956), including the fact that it's faster towards the middle. I imagined a river of asphalt and it was kinda cool.

[mauvehaus]

> In Boston, IMO they would be at least as good as the Green Line :)

Yeah, but the E line down South Huntington would be downright perilous :-D