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Hyperloop

spacex.com

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Re: Hyperloop

#351

Post by skore »

rthomas6 wrote: post #53

I am skeptical of the proposed cost were someone to actually build this. Sure, the cost of materials, labor, engineering, etc. is probably accurate, but something like this has never been built before. What about the cost of research and testing? Not to mention there doesn't currently exist an industry of contractors to build most of the parts of this system, which is not true in the case of traditional high speed ra…

That may be true, but the only thing you really need is to find a company that is willing to build this while chipping in some of the R&D cost.

I don't think such a company would be hard to find because if they get this done, they are now the only vendor of a highly desirable technology. Pretty sure they'll be able to get back that early investment... and then some.

(And remember - Musk contrasts $6b to what he estimates could possibly grow to $100b for the current proposal, so even if they end up needing to double their budget, they'd still be off by an order of magnitude.)

Re: Hyperloop

#352

Post by [deleted] »

dragonwriter wrote: post #250
LekkoscPiwa wrote: post #206

Earlier quoted context omitted.

but why to ask California State for subsidy? Why not to build it using private funds? I'd imagine that if this is economically sound idea there must be potential investors lining up to have their share in the Project? The estimated cost is $7B. Now, Musk just needs to make a few calls to his friends at Google, Amazon, etc. Can't these guys just form a company together just to build it? Maybe I'm naive... or maybe Mus…

> but why to ask California State for subsidy? Why not to build it using private funds? Because you can't, in practice, acquire the rights of way necessary to build a substantial railroad/hyperloop/freeway or other major infrastructure project of that type without government (specifically, without use of eminent domain).

[deleted]

Re: Hyperloop

#353

Post by ars »

"by placing solar panels on top of the tube, the Hyperloop can generate far in excess of the energy needed to operate."

He seems to be planning to build this over farmland? Because farmers aren't going to be happy about someone blocking their light.

Light is the limiting factor in plant growth.

If he's going to block the light to farms he'll have to pay them for the lost crops, and then he might as well just buy the land.

Re: Hyperloop

#354

Post by Thiz »

Pretty but absurd.

With all that money I rather give a Cessna to 1M people so they can fly anywhere without restriction.

Or make special small airports for direct flight between cities. Much less infrastructure.

Kudos to Elon, I love they guy and his incredibly visionary mind.

Re: Hyperloop

#355

Post by jacoblyles »

jeffasinger wrote: post #229
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…

The tube is not nearly as wide or heavy as a traditional train, so I don't know that it's fair to say that you can just as easily put a train up on pylons as you could this tube. It's interesting to think about, but also there are probably much higher costs associated with a completely untested system like this than estimated. I wouldn't be surprised if this system, if it actually worked at all, ended up being more e…

My bet is that Elon could build the Hyperloop closer to budget than the state of California could build a traditional train. Leadership matters.

Re: Hyperloop

#356

Post by rthomas6 »

skore wrote: post #351
rthomas6 wrote: post #53

I am skeptical of the proposed cost were someone to actually build this. Sure, the cost of materials, labor, engineering, etc. is probably accurate, but something like this has never been built before. What about the cost of research and testing? Not to mention there doesn't currently exist an industry of contractors to build most of the parts of this system, which is not true in the case of traditional high speed ra…

That may be true, but the only thing you really need is to find a company that is willing to build this while chipping in some of the R&D cost. I don't think such a company would be hard to find because if they get this done, they are now the only vendor of a highly desirable technology. Pretty sure they'll be able to get back that early investment... and then some. (And remember - Musk contrasts $6b to what he estim…

Very good point. Another possibility is some forward-thinking government paying for the initial R&D effort to have one of these built in their state/country.

Re: Hyperloop

#357

Post by Anechoic »

pxtang wrote: post #339
Anechoic wrote: post #315

Earlier quoted context omitted.

Putting the railway or tubes on pylons would give you an opportunity to dampen or otherwise transform those vibrations wouldn't they? Maybe, maybe not. Guideway supports (pylons) are typically founded into the bedrock which does reduce vibration somewhat, but the vertical motion of the pylon moving against the soil will still generate shear waves. This is why a demonstration project would be useful.

I recall reading that the pylons had vertical and horizontal dampers to protect against earthquakes (among other minor natural changes), so wouldn't those dampers be able to cancel out the shear waves?

No. Well, I suppose you could design an active vibration system to (almost) completely cancel the vertical vibration motion, but know you're talking about a powered system in each pylon of incredible complexity.

Passive resilient systems could help with higher frequency vibration (above say 100 Hz or so, depending on the forces and weights involved), but for lower frequency vibration (especially below 20 Hz), the resilient elements would have to be so compliant that even a gentle breeze would create very high vibrations in the guideway itself, which would be incompatible with the speeds of the cars inside.

You could make the pylons so massive that the forces from the vehicles couldn't move it, but again you're talking about higher construction and material costs, as well as visual impacts.

Re: Hyperloop

#358

Post by jim-greer »

Turing_Machine wrote: post #312
goodcanadian wrote: post #270

Earlier quoted context omitted.

Can you elevate rail as easily? The short answer is, "yes." I've ridden on it. The slightly longer answer (as another commenter has pointed out) is that it depends on the weight of the train versus the weight of the hyperloop. I see no fundamental reason to assume that the hyperloop is lighter than the train. It could be so, but then, we could make smaller and lighter trains, too (light rail). Plus you don't get the…

"I see no fundamental reason to assume that the hyperloop is lighter than the train." Did you actually read the PDF? It doesn't carry its motor with it. That's a pretty big reason. Nor does it need the heavy-duty (and heavy!) trucks of a standard rail car.

A bigger factor is that the efficiency of a train depends on having all the cars connected to each other. With the hyperloop, the pods are spaced out, so there's no need for the structure to bear the load of a bunch of them at once.

Re: Hyperloop

#359

Post by rdl »

Wow. I was expecting it to be something like the UW Ram Accelerator (RAMAC), but he put a fan in front. I was thinking it would have natural gas/detonation for propulsion, using the ram jet principle, and continuous acceleration, but I guess that rapidly gets you to totally absurd speeds (10km/sec+) and wouldn't really be viable, plus humans aren't so into 10G+ acceleration even when mounted laterally.

I would totally ride this. I hope there's a way for California to build it, and more importantly, I hope we can fix our government somehow to allow projects like this to actually happen in multiple fields.

Re: Hyperloop

#360

Post by chrismealy »

cma wrote: post #193
aaronmarks wrote: post #75

Earlier quoted context omitted.

From the report: "...with capsules departing as often as every 30 seconds from each terminal and carrying 28 people each. This gives a total of 7.4 million people each way that can be transported each year on Hyperloop."

Eventually hits up against this problem: http://books.google.com/books?id=DenWKRgqzWMC&pg=PA67&lpg=PA...

Schelling! Forgot about that one.
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