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Hyperloop

spacex.com

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Re: Hyperloop

#711

Post by krichman »

thrownaway2424 wrote: post #688
LockeWatts wrote: post #677

Earlier quoted context omitted.

You're still missing the part where it incurred interest, so it wasn't free in the least.

Musk put $40m into Tesla and his stake is worth billions. The people put $465m into Tesla and their stake is worth nothing, after making a paltry $12m in interest. In addition, while Tesla was paying the government 3% on that loan, they were paying Musk 10% on his loans, in effect shoveling government money directly into Musk's account. This is a classic example of socializing the risk while privatizing the profits.…

Sounds like he took advantage of an ignorant government. I'd do the same. So did Wall Street, but we got less back from that one.

Re: Hyperloop

#712

Post by manmal »

jarek wrote: post #654
enraged_camel wrote: post #608

Earlier quoted context omitted.

>>I think tesla motors releasing an affordable car would benefit the world a lot more than the hyperloop. Specifically, an affordable Tesla car could benefit the entire world, whereas the Hyperloop would (at least initially) only benefit people living in LA and SF.

What are the benefits to the world market of an affordable Tesla compared to, say, a modernized version of the Volkswagen Lupo, or a plug-in Up! ?

They both benefit the world. Fact is, there is no modernized 3-Liter-Lupo, and I've heard no rumors that there ever will be (?). Until there is, Tesla will be the one who demonstrates what is possible.

Re: Hyperloop

#713

Post by XorNot »

alcari wrote: post #697
robryan wrote: post #517

Earlier quoted context omitted.

That would be great, all you need is 1 country somewhere in the world to prove viable and it becomes a much safer political prospect elsewhere. Until a major accident at least like with Fukushima and nuclear.

You mean Chernobyl and nuclear, or Three Mile Island and nuclear? Both of those had already soundly killed the prospect for large-scale nuclear power in the US long before the earthquake in Japan.

Also frankly, nuclear is its whole own category of unviable for its own special reasons. Cars, buses, trains, planes and ships have all killed scores more people then nuclear power ever will.

Re: Hyperloop

#714

Post by Daniel_Newby »

LockeWatts wrote: post #685
robomartin wrote: post #675

Earlier quoted context omitted.

European unions do not behave as American unions do. They seem to know how to balance their wants with the idea of allowing their host to survive, grow and succeed. American unions tend to extract as much blood as possible out of their hosts. They are really selfish, to the point of causing terminal damage. Look at the cities they've killed off.

Can you take your political opinions and shove them down a dark hole somewhere? Most people are here for a discussion of the technology, not your rhetoric.

American unions are political patronage jobs. They will quite cheerfully spend the entire budget digging holes and filling them back in.

If you do not account for this, you will have no budget left for technology.

Making the design an open source project is a major step towards European style (socialist) unions, where the unions help decide what to do and how to make it succeed.

Re: Hyperloop

#715

Post by Daniel_Newby »

marshray wrote: post #349
sitharus wrote: post #265

Earlier quoted context omitted.

I really doubt the steam tank will be inside the pressurised volume. If they fail they would vent overboard. While an explosive failure would probably cause problems it wouldn't expose the passengers to high pressure steam. The failure mode for composite overwrap pressure vessels is a slow leak, due to the overwrap containing the metal.

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.

Re: Hyperloop

#716

Post by XorNot »

escoz wrote: post #420
mpyne wrote: post #321

Earlier quoted context omitted.

Indeed, I started getting giddy when he was discussing how to get the best power factor from the stator of the linear induction motor. It's obvious there's been a lot of thought put into this. On the other hand even with a recommendation to use something similar to TSA doing something similar to airport security, his response plan to a terrorist attac--, er, a "human related incident" is basically to say that the sys…

He does mention luggage would be 1) handled by hyperloop employees 2) removed from the pod all at once to be handled at a different time. Probably more like these pods, which are mostly "blast resistant" http://www.freepatentsonline.com/6918501.html

The big benefit of being "not a plane" is that your emergency measures can be built around that concept. There's also a big benefit to only moving 30 people at once - terrorism looks for mass casualties or mass hostages. Blowing up a hyperloop is basically like bombing a bus - no one really bothers to try.

The big benefit of hyperloops over planes would all depend on how quickly you could brake those pods and re-pressurize the tube to let people escape. Because that's something you definitely can't do on a plane and it governs most of our thinking about them - if anything happens, you're possibly over an hour from being able to land anywhere and no one is able to get off quickly.

Re: Hyperloop

#717

Post by Daniel_Newby »

HCIdivision17 wrote: post #592
shabble wrote: post #559

Earlier quoted context omitted.

I imagine you might be able to locate flaws with a custom capsule along the lines of a pipeline pig[1]. It would be exceptionally hard to actually fix it from the inside whilst travelling, so you either need to do it from the outside (which requires site access and elevation gear), or bypass/shut down the tube and fix internally. [1] https://en.wikipedia.org/wiki/Pigging#Intelligent_pigging

As Balgair notes, you can get away with a lot on the short run, but leaks are notoriously difficult to patch up. Vacuum leaks are super hard to detect at these pressure ranges, where you're lucky to hear or feel them at all. More than likely, your only indication is to leak helium into the system on purpose and use a mass selector on the outside to 'sniff' for ambient helium (which is extremely rare normally). It's t…

I would actually expect leaks to be easy to detect. Just run a high-frequency high-voltage plasma discharge detector on a skeleton vehicle. Wherever the discharge quenches you have a leak. Barcodes laser etched during construction could help you localize the leak to within a few centimeters.

Pinholes might be repairable by pressing a sapphire drift against the leak and melting the metal underneath by shining a laser through.

Re: Hyperloop

#720

Post by 6ren »

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…

The pod is basically flying. Although its weight of course is still ultimately borne by the pythons, perhaps it's mushed out and dampened in a way that reduces the ground-boom effect? But it sounds like one of the (many) bugs that must be worked out. spaceX wasn't all smooth sailing.
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