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Hyperloop

spacex.com

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Re: Hyperloop

#521

Post by CodeCube »

mpyne wrote: post #293
LekkoscPiwa wrote: post #261

Earlier quoted context omitted.

Can't (1) and (2) be solved by additional $1b to cover "cost" the Government might have? Just make it easier for them to move it through legislature, mountains, and such ;-)

You can already get the same effect by having a private investor agree to "pay back" the Government if there are really private investors who want to do that. It's called a "public-private partnership" and it's not completely impossible but it does require some person or persons to cough up the cash.

Here's an example of a public-private partnership between Rhode Island and Curt Schilling's 38 Studios - http://www.engadget.com/2012/09/07/38-studios-collapse-and-r...

Re: Hyperloop

#522

Post by VladRussian2 »

9999 wrote: post #370
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…

Jerry Brown's political career is coming to an end, so there are no long term political consequences for him. He's also traditionally been an opponent of government waste. I don't think it's unreasonable to believe that he would choose an unproven but promising technology over our existing useless high speed rail project. The assembly is another matter. If you think hyperloop is interesting, write and call your state…

>He's also traditionally been an opponent of government waste.

he is in bed with gov employees unions (the unions are primary driving force behind 200-300K/year gov employees pensions (http://www.mercurynews.com/salaries/pensions) with retirement age of 55, CA is something like $200B deep in that hole), and especially with prison guard union - of course huge prison population resulting from "toughness on crime" may not be viewed as government waste by some.

Building a bridge or high-speed rail to nowhere - just a [large] peanut in that picture.

Re: Hyperloop

#523

Post by dllthomas »

lmg643 wrote: post #180
aresant wrote: post #32

"In the case of the Hyperloop, Musk started focusing on public transportation after he grew disenchanted with the plans for California’s high-speed rail system." And who says that big government stifles entrepreneurial innovation? If ALL Musk does with the Hyperloop announcement is shed more light on the potential debacle that is to be our $70b+ high-speed rail in California, we owe him a debt of gratitude. PS - Dire…

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…

How about spend the full amount, but on more links? That way, you're employing probably more people, both short term and long term.

Re: Hyperloop

#525

Post by ricardobeat »

omegant wrote: post #393
julian37 wrote: post #287

Earlier quoted context omitted.

Isn't that the case with planes also? As far as I know, at 35,000 feet altitude you'd die, too, if cabin pressure drops and the plane's life support system fails. And I don't recall ever hearing of an air plane accident that involved suffocation.

Look at the Armstrong limit (at 62,000´), a mayor problem to overcome if the tube is going to be at the equivalent pressure of 150,000´ http://en.wikipedia.org/wiki/Armstrong_Limit http://en.wikipedia.org/wiki/Time_of_useful_consciousness Also look at the TUC (time of useful consciousness) that it´s below 5 secs when flying that high. That means that you have less than 5 secs to put your oxigen mask on before you los…

From the linked article:

    At or above the Armstrong limit, exposed bodily liquids 
    such as saliva, tears, and the liquids wetting the alveoli 
    within the lungs — but not vascular blood (blood within the     
    circulatory system) — will boil away without a pressure suit
As mentioned above, we have been boarding planes without pressure suits for decades, and the hyperloop has two security advantages: it has a large supply of compressed air to work with, and the tunnel can be quickly re-pressurized in the event of a severe rupture. A multitude of concurrent failures (much less likely than those in an airplane) would be necessary for a catastrophe.

Re: Hyperloop

#526

Post by Turing_Machine »

krschultz wrote: post #474
Turing_Machine wrote: post #439

Earlier quoted context omitted.

Sorry if you perceived that as "nasty". The motor that it carries with it is about 146 horsepower. That's less than a Kawasaki Ninja street bike. The General Electric E60 locomotives currently in use on Amtrak crank out 6,250 hp (4,660 kW) and weigh 423,000 lb (192,000 kilograms). The weight of the tube doesn't really enter into it.

The weight of a 10' diameter steel tube with 1" wall thickness is 125,000 lbf per 100 feet. Note that does not include the reinforcing braces, that is just the plate. The actual weight could be easily 2-4x greater. It also doesn't include the weight of the solar array. My bet is that it's not significantly different to compare a light rail (subway-like) system to a hyperloop in terms of weight.

The weight of the track ballast alone is more than that. Gravel is about 100 pounds per cubic foot, and you need about 12 cubic feet of ballast per foot of track, or 127,500 pounds.

Then you get to add the rails and ties (or concrete sleepers), plus the vastly more heavy rolling stock.

The reason I said that the weight of the tube doesn't enter into it is because the tube isn't moving. The only thing that matters in terms of energy use is the rolling stock.

Re: Hyperloop

#527

Post by dllthomas »

abruzzi wrote: post #317
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…

The problem is that, at least with the CA high speed rail system, the design is all theoretical at the moment. It may be a brilliant idea, but but moving from the core ideas in the document to actual working, build-able products, can be a slow process. And given the state of where CA is on their project, that may not put them on the same window.

The R&D can't happen in government, but in some ways that's better - government projects are slower than this needs to be. What we need is for someone(s?) with deep pockets to bank-roll prototypes &c.

Re: Hyperloop

#528

Post by sillysaurus »

krschultz wrote: post #459

This is very serious first proposal. As a professional mechanical engineer I have worked on high quality steel tubes (nuclear submarines) before. The immediate thing that sticks out to me in this proposal are the tight mechanical tolerances that have to be maintained. Talking about tens of thousandths of an inch tolerances on a 10' diameter tube is not to be dismissed lightly. That is going to be tough to maintain -…

Offtopic, but please consider writing some blog posts or articles about your experiences working on nuclear submarines. That just sounds so cool, and while the work is probably dull, I'd nonetheless be fascinated to read some detailed stories.

Re: Hyperloop

#529

Post by marshray »

corwinstephen wrote: post #382
greedo wrote: post #214

Earlier quoted context omitted.

I'm sure the seatbacks would all have some net connected display for movies or actual computing.

Are you? I wouldn't rule it out, but personally I think getting an outside signal into a sealed capsule which is moving so rapidly that it must use battery power rather than a physically connected power source seems more than trivial.

Nah, wifi would travel great in a long metal tube.

Re: Hyperloop

#530

Post by yk »

Anechoic wrote: post #224
goodcanadian wrote: post #188

I am intrigued, but not overwhelmed. Many of his reasons why his hyperloop is superior to high speed rail are not specific to the hyperloop. For example, you can put railway tracks up on pylons, too, with very little impact on the ground. It is common to do this in urban areas, but it is rarely done in rural areas because it is flat out cheaper to put it on the ground. I don't believe that an experimental tube is goi…

I don't believe that an experimental tube is going to be somehow magically cheaper and easier to route and build than train tracks. Do you really think the special interests that are making HSR so difficult and expensive would say, "Oh, do whatever you like with your tube."? These are extremely important issues that advocates seem to be glossing over. Putting the guideway on pylons doesn't magically eliminate land is…

> one important reason I have to deal with is that the speed of shear waves through soil is only on the order of a couple of hundred miles per hour.

Perhaps a stupid question, but the shock wave forms because the trains is moving continuously over the ground? So if you put the entire thing on stilts, there would be one wave formed at t0, x0 when the train reaches pylon 0 and the next wave would be at t1, x1 etc. So the interference pattern for the waves would look vastly different. ( This holds of course only for point like trains... )

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