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Hyperloop

spacex.com

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Re: Hyperloop

#971

Post by kore »

acqq wrote: post #940
rtkwe wrote: post #928

Earlier quoted context omitted.

You're in control of your car though so if you need to you can stop and get out to deal with any bodily functions or sickness. You can't do that in this train. There's a lot to be said for the effect of just having the option even if you don't exercise it. Control is very comforting to people.

Not only comforting, the seemingly "rare" cases actually happen all the time and the advantages of being able to stop, go out, help the person etc. are effectively used all the time. Designing mass transportation while ignoring such aspects is like programming without handling the limit cases "it works for N between 2 and 100 but not for 0, 1 and MAX_INT, even if these are allowed inputs." It's bad, very bad for the…

With multiple stations between SF and LA, this could be mitigated with an emergency system that pulls the train off at the next stop. Similar to how some buses or trains have emergency stop systems, except instead of stopping, the capsule would divert to the next station.

Re: Hyperloop

#972

Post by roblev »

acqq wrote: post #940
rtkwe wrote: post #928

Earlier quoted context omitted.

You're in control of your car though so if you need to you can stop and get out to deal with any bodily functions or sickness. You can't do that in this train. There's a lot to be said for the effect of just having the option even if you don't exercise it. Control is very comforting to people.

Not only comforting, the seemingly "rare" cases actually happen all the time and the advantages of being able to stop, go out, help the person etc. are effectively used all the time. Designing mass transportation while ignoring such aspects is like programming without handling the limit cases "it works for N between 2 and 100 but not for 0, 1 and MAX_INT, even if these are allowed inputs." It's bad, very bad for the…

The Channel Tunnel between the UK and France works fine, and if someone got sick at the start of the tunnel section then there isn't too much that could be done quickly.

The public seems to have no issue with that concept, it is a simple risk that goes with getting on the train.

http://en.wikipedia.org/wiki/Channel_Tunnel

Re: Hyperloop

#973

Post by marshray »

Daniel_Newby wrote: post #715
marshray wrote: post #349

Earlier quoted context omitted.

A vehicle near the end of its ride will be carrying up to 818 kg (1800 lb) of superheated steam (127 C, 260 F). The 4000 kg (8,900 lb) of onboard batteries and 1800 kg compressor will be dumping heat too. This is 6600 kg of "hot stuff", whereas the entire capsule is projected to have a mass of 15000 kg. The current design has the passengers in an enclosed capsule in between the compressors and the batteries, with a p…

I wonder why they do not use ice. Melt it as a heat sink in normal operation, and vent it to the tunnel for emergency evaporative cooling.

Room-temperature water is readily available, easier to handle, and works almost as well.

Re: Hyperloop

#974

Post by ajays »

ewoodrich wrote: post #275
lmg643 wrote: post #180

Earlier quoted context omitted.

Interesting point that big government provoked the advancement of the hyperloop idea - counterintuitive idea, and clearly yes. but any idea like this will need government cooperation. The real test of big government will be how they respond to the hyperloop. magic response: "of course we may be wrong, we'll look into this immediately." and then they decide to build it. likely answer: praise, perhaps even an evaluatio…

It was approved by a ballot measure, so in this case it may be the "idiocy" (or will) of the voter. http://ballotpedia.org/wiki/index.php/California_Proposition...

(I voted against it) In the ballot, they claimed a cost of $45B. But after the measure passed, the cost ballooned to $98B (yes, you read that correctly). Then, after howls of protest, the cost now is $68B.

Re: Hyperloop

#975

Post by paulus99 »

A wonderful proposal and inspiring: I think the air bearing, partially evacuated tube and axial flow compressor powered by onboard battery are an innovative combination worth exploring, and I am sure with the correct leadership and political will could produce a really useful enhancement of transport infrastruture. However on reading many of the comments bemoaning current state of construction in the US, as well as unions and vested interests; had to provide this quote of Machiavelli's: It ought to be remembered that there is nothing more difficult to take in hand, more perilous to conduct, or more uncertain in its success, than to take the lead in the introduction of a new order of things. Because the innovator has for enemies all those who have done well under the old conditions, and lukewarm defenders in those who may do well under the new. This coolness arises partly from fear of the opponents, who have the laws on their side, and partly from the incredulity of men, who do not readily believe in new things until they have had a long experience of them.

Re: Hyperloop

#976

Post by tocomment »

DonPedro wrote: post #952
tocomment wrote: post #854

A thought I just had, could a hyperloop like technology be used to launch ships into orbit? Why or why not?

Not by itself, but maybe in combination with another technology: http://www.popsci.com/technology/article/2010-11/nasa-engine... Whatever you were launching would have to move through normal air, not the minimal pressure you have in the Hyperloop tube. It is hard to pass an airlock at supersonic velocities...

Could you gradually re-introduce air pressure at the end of the tube before the payload exits towards orbit?

Re: Hyperloop

#977

Post by Agathos »

acqq wrote: post #940
rtkwe wrote: post #928

Earlier quoted context omitted.

You're in control of your car though so if you need to you can stop and get out to deal with any bodily functions or sickness. You can't do that in this train. There's a lot to be said for the effect of just having the option even if you don't exercise it. Control is very comforting to people.

Not only comforting, the seemingly "rare" cases actually happen all the time and the advantages of being able to stop, go out, help the person etc. are effectively used all the time. Designing mass transportation while ignoring such aspects is like programming without handling the limit cases "it works for N between 2 and 100 but not for 0, 1 and MAX_INT, even if these are allowed inputs." It's bad, very bad for the…

Yes, that's why we built that airport and hospital on the North Pole. Now intercontinental flights can make emergency landings in under 30 minutes at all times.

Re: Hyperloop

#978

Post by nmeofthestate »

jacquesm wrote: post #258

I'll just leave this here: http://jacquesmattheij.com/elon-musk-and-the-hyperloop Looks like I nailed most of it. So, who is going to build a proof-of-concept scale model of this thing a few kilometers long?

Sorry - I'm afraid you were wrong on almost all, if not all, counts.

Tunnel is pressurised - wrong.

Use of the word "loop" means that something is 'recycled' - wrong.

Parallel tracks used for acceleration - wrong.

Carriages help push each other - wrong.

Internet analogy - wrong.

Summary: scaled up pneumatic tube - wrong.

Re: Hyperloop

#979

Post by evolve2k »

fooqux wrote: post #869
lessnonymous wrote: post #505

Earlier quoted context omitted.

2.8/km² Australia And here you can travel from most parts of Melbourne to most parts of Sydney with just two train changes. One at a Melbourne hub to the interstate trains and one at Sydney to the local system. Even so, we feel our train systems suck too.

That figure is meaningless considering Australia is a large piece of largely uninhabited land, with two or three metropolitan areas on the coasts. Unless you can take a train into the center of Australia, in which case I apologize.

http://en.wikipedia.org/wiki/Central_Australia_Railway

Re: Hyperloop

#980

Post by nmeofthestate »

27182818284 wrote: post #136

I honestly expected better work. I feel like this is something everyday users on Reddit or HN could have put together in a report. I only gave it a look because Elon Musk's name is on it. That says something sad about me when it comes to the Big Imagination projects :-/

I feel like this is something everyday users on Reddit or HN could have put together in a report.

I'm not so sure. When Hyperloop was unknown, HN spent far too much time enthusing about obviously nonsense guesses about what Hyperloop might turn out to be. Let's not get too conceited about HN's abilities.

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