Hyperloop: Pipes of Fancy • Hacker News Board

Re: Hyperloop: Pipes of Fancy

#211

Post by dmitriid » Thu, Aug 13, 2020, 6:55 AM UTC

keenmaster wrote: post #179

jcranmer wrote: post #165

Earlier quoted context omitted.

> - 2-3x speed of bullet trains. Can change the way we perceive geographic distance. > - Cost isn't as much of a concern because a national hyperloop network would create a lot more value than a bullet train equivalent. High speed brings with it some pretty severe problems. The most well-known is curve geometry: curve radii scale with the square of velocity. Transition track (how long the "S" of a S bend needs to be)…

Couldn't the capacity issue be somewhat mitigated by stacking tubes vertically and/or increasing the tube diameter? As for the curvature issue, there seem to be a couple ways around that. One is to straighten the route to the maximum extent possible (not trivial but not impossible for some routes). The other is to build massive curves and decelerate into them. Again, there are tradeoffs (cost,speed) but it's not impo…

> Couldn't the capacity issue be somewhat mitigated by stacking tubes vertically

Significantly increased costs

> and/or increasing the tube diameter?

Immeasurably increased costs. Because hyperloop already operates on the idea of operating in vacuum. So let's say you have a 10-kilometer tube that you need to keep in vacuum and you want to increase its diameter...

Re: Hyperloop: Pipes of Fancy

#212

Post by dmitriid » Thu, Aug 13, 2020, 6:57 AM UTC

Ajedi32 wrote: post #119

sudosysgen wrote: post #106

Earlier quoted context omitted.

Our subway system in Montreal runs at a frequency of anywhere from 2 minutes to 7 minutes. There are even faster ones.

That's still 2 to 7 minutes longer than a Loop tunnel. And that also only addresses half of the GP's comment (scheduling).

Yeah-yeah. Because cars are magically teleported in and out of the hyperloop tunnels.

Re: Hyperloop: Pipes of Fancy

#213

Post by [deleted] » Thu, Aug 13, 2020, 7:23 AM UTC

TigeriusKirk wrote: post #67

ashtonkem wrote: post #63

Earlier quoted context omitted.

This seems worse than a subway in pretty much every metric, unless if you happen to be same person who's selling the cars that it's compatible with.

There are a number of metrics where it's clearly better. Scheduling and routing. Not waiting 10-30 minutes for the next train depending on time of day. Not stopping anywhere but your destination. No connections or changeovers. Personal space. Privacy, safety. Regardless of how you personally feel about this factor, it matters enough to some people to significantly impact usage. Those factors may or may not be enough…

[deleted]

Re: Hyperloop: Pipes of Fancy

#214

Post by The_Double » Thu, Aug 13, 2020, 7:29 AM UTC

sudosysgen wrote: post #109

Miraste wrote: post #103

Earlier quoted context omitted.

This article[0] talks about how locals were shooting at it, although it doesn't mention the berms (talking to the sheriff must not have worked out). I think a hyperloop could avoid this problem by not locating in Louisiana. [0] https://www.225batonrouge.com/article/good-vibrations

What do you do when a terrorist shoots a hyperloop tube causing a pressure wave that will kill everyone inside?

What do you do when a terrorist places a derailing device [0] on a piece of rail track that will harm and potentially kill many people inside?

[0]:https://en.wikipedia.org/wiki/Derail

Re: Hyperloop: Pipes of Fancy

#215

Post by thdrdt » Thu, Aug 13, 2020, 7:36 AM UTC

aidenn0 wrote: post #202

noahtallen wrote: post #160

Earlier quoted context omitted.

I think the counterpoint in the US is that most cities are very far apart and there is practically nothing in between. Obviously places like the northeast corridor or the Bay Area are much more dense. But even a route from SF->Seattle is mostly traveling through non-dense areas. That gets even better across the west and Midwest

Wires than that. Most people live on the border of the cities and the nothing. Suburbs are practically designed to make mass transit expensive and slow.

This is why I don't get why gondola lifts are not more popular for both people and cargo.

Maybe in cities the wind is an issue.

Re: Hyperloop: Pipes of Fancy

#216

Post by andbberger » Thu, Aug 13, 2020, 7:38 AM UTC

nick_kline wrote: post #166

andbberger wrote: post #84

Earlier quoted context omitted.

Waiting 10-30 minutes for a train isn't a technological consequence of rail transportation, it's a symptom of a catastrophically inept transit agency. What's stopping, say, Caltrain, from running trains at peak frequency all day? Incompetent leadership. They have the trains (which spend all day sitting idle _at_ terminus platforms), the have the crew (who also sit idle during the day), they have the capacity to run m…

Well, they don't run them all day because of the cost of the use of the trains and the cost of the crews. The crews can't be paid all day to do nothing.

The crews can absolutely be paid all day to do nothing.

Re: Hyperloop: Pipes of Fancy

#217

Post by SubiculumCode » Thu, Aug 13, 2020, 7:41 AM UTC

High speed transportation could cause an exodus to areas with sparser populations but maneable commutes to city centers. Live in Utah, work in SF

Re: Hyperloop: Pipes of Fancy

#218

Post by fastball » Thu, Aug 13, 2020, 7:51 AM UTC

joering2 wrote: post #12

smikhanov wrote: post #6

3.5 years on my prediction holds well: https://news.ycombinator.com/item?id=13811365

you need to fix your clock, its not 2027 yet.

The prediction holds, not the prediction is decided.

Re: Hyperloop: Pipes of Fancy

#219

Post by manigandham » Thu, Aug 13, 2020, 7:56 AM UTC

cs702 wrote: post #4

"A hyperloop system involves passengers or freight transported by pods elevated by magnets, which travel within raised pipes. The pods can be propelled at 620mph (1,000kph), says Jay Walder, boss of Virgin Hyperloop One, one of the firms pushing the idea. At that pace 'you could move between Columbus and Chicago in 40 minutes', he says, so covering the 460 miles many hours quicker than by driving and at a cost (and o…

It already exists for freight. We have a large train network that is extremely efficient. Decreasing carrying capacity while vastly increasing energy costs isn't worth it just for a gain in speed.

Re: Hyperloop: Pipes of Fancy

#220

Post by reify_null » Thu, Aug 13, 2020, 7:59 AM UTC

chroma wrote: post #21

smikhanov wrote: post #6

3.5 years on my prediction holds well: https://news.ycombinator.com/item?id=13811365

With any new technology, the likelihood of failure is high but the expected value is positive. As Nat Friedman (CEO of GitHub) said: "Pessimists sound smart. Optimists make money."

Talk about a false dichotomy there. No person is fully a pessimist or optimist. Framing it in terms like this just serves to stifle actual discussion. A nice soundbite from someone who happened to be optimistic about the right thing.