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Hyperloop Alpha [pdf]

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Re: Hyperloop Alpha [pdf]

#181

Post by ash »

ianb wrote: post #157
resu wrote: post #21

If the U.S. doesn't take this on, I hope another country with a big appetite for enormous public transit projects takes this on. Japan, Korea, and China, I'm looking at you...

China seems set on a different path, but I guess you never know. Korea seems too small to benefit. And Japan perhaps too mountainous? Looking at California: http://bit.ly/1eFevxA And Japan: http://bit.ly/19ZXwbJ I don't see any roads in Japan that are nearly as straight as I-5. The places where this would make sense have destinations fairly far apart, but not too far apart, with somewhat amenable landscape between th…

> Russia

Yes, 630+ km Hyperloop between Moscow and Saint-Petersburg would be a great project. Problems:

1. Winter. Would solar panels give enough energy during winter?

2. Highly-inflated cost due to corruption. I would speculate corruption is a big problem for California HSR too, given its cost.

3. "Russian Railways" company monopoly for all intercity railways in the country.

Re: Hyperloop Alpha [pdf]

#182

Post by triplepoint217 »

realrocker wrote: post #147

Anyone has the resources from this pdf and willing to commit to github? Lets start forking!

I sent a request to their feedback email seeing if they would be open to something of that sort. Copy pasting formatting to Markdown/ReST wouldn't be too bad, but it seems to me polite to ask permission.

Re: Hyperloop Alpha [pdf]

#183

Post by neurotech1 »

LockeWatts wrote: post #159
Niten wrote: post #145

Earlier quoted context omitted.

Well it's not just a matter of bathrooms. Even on a commuter bus or plane, if someone has a medical emergency and needs to get off right now , the bus will pull over or the plane will land. In this design you'd have to just sit there, helpless, until the vehicle reaches its destination. Heck, even if you're a doctor in the next seat you wouldn't be able to get up and help your fellow passenger.

Landing a plane will guaranteed take more than 35 minutes. With the hyperloop, it's simpler and more efficient to just have EMTs called and on station when the car arrives.

Actually, an airliner can usually descend and land within 10-15 minutes in an emergency, assuming a suitable runway is close by. There are more smaller airports with 5000 ft runways that don't typically handle 737s or larger.

The problem with emergencies at major airports is that between EMTs and fire services inspecting the jet, that runway is out of service for at least 30 minutes.

On a normal flight a 737 flies an approach at under 180kts but the approach limit is a lot faster. In a cardiac arrest type situation, the pilot may decide to fly a faster approach into an airport with medical services available. They would still touch down at the normal speed.

Re: Hyperloop Alpha [pdf]

#184

Post by schiffern »

Someone wrote: post #90
tlb wrote: post #39

He doesn't properly address thermal expansion of the entire system. A long straight steel tube from SF to LA will expand a total of 300 meters over a 40C temperature change. Where does it go?

"By building a system on pylons, _where_the_tube_is_not_rigidly_fixed_at_any_point" [...] "A telescoping tube, similar to the boxy ones used to access airplanes at airports would be needed at the end stations to address the cumulative length change of the tube" So, the tube is lying loose on the pylons, and he assumes it will keep its shape while expanding. I think that is highly optimistic for a tube that is a strai…

>If he manages to accomplish that, the end stations will move over 300 meters, in total.

Where are you getting this idea from? That seems like an insane implementation compared to using accordian-like flexible section[s].

Re: Hyperloop Alpha [pdf]

#185

Post by [deleted] »

zeckalpha wrote: post #91
keiferski wrote: post #4

Earlier quoted context omitted.

It says right at the beginning that the first section is an overview while the second section is more technical...

So? It needed a section with more polish than the first section for not HN, and a more detailed technical section.

[deleted]

Re: Hyperloop Alpha [pdf]

#186

Post by orofino »

cmbaus wrote: post #119
orofino wrote: post #29

Earlier quoted context omitted.

You're thinking city buses. I'm thinking long-haul busses (like greyhound in the US). Greyhound buses likely have facilities, what I'm actually talking about are the buses used a core parts of the transportation infrastructure all over South America. Many of these also have facilities but I've been on many where the bathroom isn't functioning or just plain isn't there. You can easily travel for 30 minutes to an hour…

One of the most unpleasant (although memorable) experiences of my life was having to hold it for over an hour while sitting over the wheel well on a bumpy bus ride in the middle of Belize.

I'm not saying that it doesn't have the possibility of being unpleasant at times, I'm saying that it doesn't strike me as a serious objection to a brand new transit method that is superior to existing options in so many ways.

Re: Hyperloop Alpha [pdf]

#187

Post by vadman »

kailuowang wrote: post #35
orofino wrote: post #29

Earlier quoted context omitted.

You're thinking city buses. I'm thinking long-haul busses (like greyhound in the US). Greyhound buses likely have facilities, what I'm actually talking about are the buses used a core parts of the transportation infrastructure all over South America. Many of these also have facilities but I've been on many where the bathroom isn't functioning or just plain isn't there. You can easily travel for 30 minutes to an hour…

All these buses analogy isn't exactly the same because they still have the option to stop somewhere, which give the passengers the assurance that if they can't hold it's not the end of the world. Taking that into consideration, I think it could solve most people's bathroom concern by adding bathroom stops to the loop, in the case of semi-emergency, ideally a pod should be able to make a stop upon request within 5-10…

Not really. Take the Staten Island express bus for example. Between SI and Manhattan, there is about 35 min on the Verrazano Bridge and Brooklyn-Queens Expressway, without any opportunity to get off (BQE does not even have shoulders for the most part). That's on a good day with decent traffic. In bad traffic and bad weather, that could be an hour or even more without any opportunity to get off.

EDIT: a clarification for non-New Yorkers -- people take these daily to get to work, if they work in Manhattan. The alternative is SI railroad-ferry-subway, which allows more bathroom safety but takes quite a bit longer.

Re: Hyperloop Alpha [pdf]

#188

Post by Someone »

poub wrote: post #58
Someone wrote: post #26

Earlier quoted context omitted.

Then use http://www.bbc.com/future/story/20130812-planes-that-can-pic... . Compared to that, this Hyperloop idea is best described as "No pilot. Less space than a 747", by teenage boys. On the other, more important hand, at firt view, this looks feasible to me (taking into account who published it) I do wonder about the "little noise" claim, though. That fan a few meters in front of you that compresses air so that yo…

Oh the irony if you try to access the bbc link http://www.bbc.com/future/story/20130812-planes-that-can-pic... from the UK : «BBC Future (international version) We're sorry but this site is not accessible from the UK as it is part of our international service and is not funded by the licence fee. It is run commercially by BBC Worldwide, a wholly-owned subsidiary of the BBC, the profits made from it go back to BBC pro…

For those in the same boat: the BBC article talks of a design where maglev trains, starting in city centers, accelerate to a few hundreds km/h and then get picked up by a huge flying wing that swoops on it like a bird of prey. Later, much farther away, that flying wing will put the trains back on a maglev track, without ever landing.

See also: http://www.core77.com/blog/transportation/flotspotting_u_of_...

That truly is a toy for boys (as in "looks cool and dangerous") unlike the Hyperloop ("it may or may not be dangerous, but you can't see that, so who cares?")

Re: Hyperloop Alpha [pdf]

#189

Post by adwf »

jessaustin wrote: post #175
adwf wrote: post #106

Looks like a good idea, but the major glaring technical point that seems to be missing is the issue of horizontal stability within the tube. When you get very low friction, high speed and no tracks, you're going to start having attitude problems without the right control surfaces available. Don't want to be spinning passengers around the roof of that tunnel!

The train could be just very bottom-heavy.

Perhaps on a straight, but in the bends or slopes you'd still need some sort of control. I'm visualising the kind of oscillations that luge or bobsled riders get in the winter olympics when they come out of the corners.

High speed and low friction could mean a lot of potential lateral movement that needs to be controlled somehow. Maybe releasing some of the stored compressed gas in controlled bursts like used in various space endeavours. That would have the added benefit of off-loading some of the potentially dangerous steam.

Re: Hyperloop Alpha [pdf]

#190

Post by a_c_s »

dchmiel wrote: post #31
jessaustin wrote: post #14

Earlier quoted context omitted.

The passenger compartment mockups indicate there won't be enough room to sit upright . I'm sure the seats will make this comfortable for people of average stature who aren't afflicted with claustrophobia, but there will be much less room than tunnels that accommodate e.g. upright humans or subway trains.

Why worry initially about a disorder that only affects 5–7% of people. Fix the transportation problem for a large majority of people first, anyone else still has existing transportation as an option.

Comfort is proportional to room, there are plenty more than 7% of the population that would refuse to ride in a windowless box they can't even sit upright in.

Remember there are two passenger compartment mockups, this is the smaller one we are referring to: http://i.space.com/images/i/000/031/716/i02/hyperloop-passen...

Unscientifically I'd bet less than 25% of people would be willing to ride in that for more than 10 minutes, much less 30-40.

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