5 ms·

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 on

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 :)

mauvehaus 3y ago
> 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
mpsprd 3y ago
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...
- bee_rider 3y ago
  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 3y ago
    You also have to consider what happens if a 60mph belt breaks/halts while people are on it.
- user982 3y ago
  Are you sure it wasn't The Caves of Steel?
  - mpsprd 3y ago
    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.
- adolph 3y ago
  Requires dexterity and seems somewhat dangerous? Meet the Paternoster elevator: https://en.wikipedia.org/wiki/Paternoster_lift https://en.wikipedia.org/wiki/Paternoster_lift
  - HideousKojima 3y ago
    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 3y ago
    "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_ 3y ago
      One death per year is literally nothing compared to cars.
      - chefandy 3y ago
        I imagine if you compared the number of injuries to the distance travelled, or even trips taken, cars would come out way ahead.
        timeon 3y ago
        In some instances (like suburbs) need for distance is increased by cars.
Andrex 3y ago
Getting out and walking was frequently as good as the Green Line when I lived there...
- occams_chainsaw 3y ago
  Same for me just in October for some stretches
twelvechairs 3y ago
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.
- soperj 3y ago
  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 3y ago
    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 3y ago
    To transport their just-bought stuff?
    - chefandy 3y ago
      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.
corlinpalmer 3y ago
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.
- anothernewdude 3y ago
  Doesn't need to be one big continuous walkway.
  - chefandy 3y ago
    The moving walkways in some airports, for example, have multiple moving sections and work just fine.
- ricardobeat 3y ago
  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.
- thereisnospork 3y ago
  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.
  - cybrox 3y ago
    Solar friggin sidewalks!
    - _kidlike 3y ago
      mmmm yes! let's make our cities even hotter
riffraff 3y ago
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.
euroderf 3y ago
In Heinlein's books, do the rolling roads come before or after the establishment of American theocracy ? Asking for a friend.
- dsq 3y ago
  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.gif http://templetongate.net/graphics/literature/fhchartlarge.gi...

mauvehaus 3y ago

> 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

mpsprd 3y ago

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...

bee_rider 3y ago
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 3y ago
  You also have to consider what happens if a 60mph belt breaks/halts while people are on it.
user982 3y ago
Are you sure it wasn't The Caves of Steel?
- mpsprd 3y ago
  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.
adolph 3y ago
Requires dexterity and seems somewhat dangerous? Meet the Paternoster elevator: https://en.wikipedia.org/wiki/Paternoster_lift https://en.wikipedia.org/wiki/Paternoster_lift
- HideousKojima 3y ago
  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 3y ago
  "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_ 3y ago
    One death per year is literally nothing compared to cars.
    - chefandy 3y ago
      I imagine if you compared the number of injuries to the distance travelled, or even trips taken, cars would come out way ahead.
      - timeon 3y ago
        In some instances (like suburbs) need for distance is increased by cars.

Andrex 3y ago

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

occams_chainsaw 3y ago
Same for me just in October for some stretches

twelvechairs 3y ago

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.

soperj 3y ago
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 3y ago
  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 3y ago
  To transport their just-bought stuff?
  - chefandy 3y ago
    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.

corlinpalmer 3y ago

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.

anothernewdude 3y ago
Doesn't need to be one big continuous walkway.
- chefandy 3y ago
  The moving walkways in some airports, for example, have multiple moving sections and work just fine.
ricardobeat 3y ago
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.
thereisnospork 3y ago
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.
- cybrox 3y ago
  Solar friggin sidewalks!
  - _kidlike 3y ago
    mmmm yes! let's make our cities even hotter

riffraff 3y ago

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.

euroderf 3y ago

In Heinlein's books, do the rolling roads come before or after the establishment of American theocracy ? Asking for a friend.

dsq 3y ago
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.gif http://templetongate.net/graphics/literature/fhchartlarge.gi...