6 ms·

I'd love for technologies like this to become a reality, but it seems unlikely this specific implementation will be able to carry any substantial volume of trav

I'd love for technologies like this to become a reality, but it seems unlikely this specific implementation will be able to carry any substantial volume of travelers.

staz 11y ago
Same here, I saw their presentation video here https://vimeo.com/98497797 https://vimeo.com/98497797 and I'm left wondering, their capsules are roughly the same size of a car, so how does that save any space at all?
- melling 11y ago
  "how does this save any space at all?" It's in the sky? I've got a longer answer if you can't think this through for yourself.
  - pavs 11y ago
    He does have a good point though. According to the video, the problem is we are building more roads to fix our existing traffic problem but they too get filled up, but int he video it shows skyTran works by being hooked to a overhead infrastructure. So you will still need to build overhead infrastructure to use ST. In theory this doesn't seem any better than adding more layers of highway. The video also suggest it as a replacement of our existing transportation system as opposed to complementing our existing system (removes all the highways and just shows the ST). So just by watching the video, I too don't see the obvious benefit.
    - chipsy 11y ago
      The usual rebuttals are: Overhead rails are smaller and cheaper than highways for the capacity, standardized pods can be lighter and smaller-scale, and the automated guidance allows shorter timings for acceleration and braking. However, when transit planners run the numbers, they come up against a different problem, which is that building this isn't really a substitute for a new metro line. The peak capacity is still more along the lines of what a highway can provide, and that wouldn't do much to improve the rush hour commute - plus, if they wanted a highway, there's always funding around for those. So the PRT approach has mostly been implemented, to date, in airport systems and private campuses.
    - melling 11y ago
      People can walk under it. Kids can play near them and it won't be dangerous. The ground is for humans who are walking, playing, or on bikes, for instance. Humans and cars interacting lead to lots of dead humans: http://gothamist.com/2014/10/15/there_have_now_been_200_traffic_fat.php http://gothamist.com/2014/10/15/there_have_now_been_200_traf...
- flexie 11y ago
  The distance between the units in a transportation system such as railroads, freeways or this Skytran is called "headway". Headway is mainly determined by breaking time. They say the capsules can break to 0 in just 16 meters so theoretically you could have one capsule per 20 meters or so (although I doubt that would be safe or feel comfortable). That's 20 meters for 2 passengers, which means that you need 1 km track for 100 passengers. If the Skytran really goes 250 km/h you could move something like 250*100 = 25,000 persons per hour per rail if the capsules are full, or 12,500 if they are half full. That could easily compete with cars, trains, metro systems, buses etc. But if the headway is really 100 meters, then we are down to 20 persons per km, and if the Skytran really "only" goes 150 km/h then we are transporting some 3,000 persons per hour if the capsules are full or some 1,500 if they are half full which is much less than a typical metro. If we go by one capsule per 20 meters, we would use up to 12,500 capsules per hour meaning that we would have to launch another capsule with one or two passengers from side tracks onto the main track every .29 seconds in peak hour. And they would not be launched on the track from the same end station and unloaded on the same end station but from many different stations on the track. That's a job for a programmer to figure out how that's done safely but I don't see it happening. And quite frankly, if you do have the backing of NASA and rich investors and this whole thing is so cheap and fast to build as they claim, why don't they just build a full scale version in some town somewhere? I see only animations and prototypes.
  - danmaz74 11y ago
    > why don't they just build a full scale version in some town somewhere? I see only animations and prototypes They're building a demo 500m track in Tel Aviv. We'll see if it works as expected.
    - waterlesscloud 11y ago
      The Tel Aviv track was supposed to be done by the end of this year. Maybe Schmidt got inside info that triggered this move?

I'd love for technologies like this to become a reality, but it seems unlikely this specific implementation will be able to carry any substantial volume of travelers.

staz 11y ago

Same here, I saw their presentation video here https://vimeo.com/98497797 https://vimeo.com/98497797 and I'm left wondering, their capsules are roughly the same size of a car, so how does that save any space at all?

melling 11y ago
"how does this save any space at all?" It's in the sky? I've got a longer answer if you can't think this through for yourself.
- pavs 11y ago
  He does have a good point though. According to the video, the problem is we are building more roads to fix our existing traffic problem but they too get filled up, but int he video it shows skyTran works by being hooked to a overhead infrastructure. So you will still need to build overhead infrastructure to use ST. In theory this doesn't seem any better than adding more layers of highway. The video also suggest it as a replacement of our existing transportation system as opposed to complementing our existing system (removes all the highways and just shows the ST). So just by watching the video, I too don't see the obvious benefit.
  - chipsy 11y ago
    The usual rebuttals are: Overhead rails are smaller and cheaper than highways for the capacity, standardized pods can be lighter and smaller-scale, and the automated guidance allows shorter timings for acceleration and braking. However, when transit planners run the numbers, they come up against a different problem, which is that building this isn't really a substitute for a new metro line. The peak capacity is still more along the lines of what a highway can provide, and that wouldn't do much to improve the rush hour commute - plus, if they wanted a highway, there's always funding around for those. So the PRT approach has mostly been implemented, to date, in airport systems and private campuses.
  - melling 11y ago
    People can walk under it. Kids can play near them and it won't be dangerous. The ground is for humans who are walking, playing, or on bikes, for instance. Humans and cars interacting lead to lots of dead humans: http://gothamist.com/2014/10/15/there_have_now_been_200_traffic_fat.php http://gothamist.com/2014/10/15/there_have_now_been_200_traf...
flexie 11y ago
The distance between the units in a transportation system such as railroads, freeways or this Skytran is called "headway". Headway is mainly determined by breaking time. They say the capsules can break to 0 in just 16 meters so theoretically you could have one capsule per 20 meters or so (although I doubt that would be safe or feel comfortable). That's 20 meters for 2 passengers, which means that you need 1 km track for 100 passengers. If the Skytran really goes 250 km/h you could move something like 250*100 = 25,000 persons per hour per rail if the capsules are full, or 12,500 if they are half full. That could easily compete with cars, trains, metro systems, buses etc. But if the headway is really 100 meters, then we are down to 20 persons per km, and if the Skytran really "only" goes 150 km/h then we are transporting some 3,000 persons per hour if the capsules are full or some 1,500 if they are half full which is much less than a typical metro. If we go by one capsule per 20 meters, we would use up to 12,500 capsules per hour meaning that we would have to launch another capsule with one or two passengers from side tracks onto the main track every .29 seconds in peak hour. And they would not be launched on the track from the same end station and unloaded on the same end station but from many different stations on the track. That's a job for a programmer to figure out how that's done safely but I don't see it happening. And quite frankly, if you do have the backing of NASA and rich investors and this whole thing is so cheap and fast to build as they claim, why don't they just build a full scale version in some town somewhere? I see only animations and prototypes.
- danmaz74 11y ago
  > why don't they just build a full scale version in some town somewhere? I see only animations and prototypes They're building a demo 500m track in Tel Aviv. We'll see if it works as expected.
  - waterlesscloud 11y ago
    The Tel Aviv track was supposed to be done by the end of this year. Maybe Schmidt got inside info that triggered this move?