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Hyperloop

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Re: Hyperloop

#781
I like the idea of transporting cars with passengers or just cars/SUVs. That would be ideal. Travel from point a to point b like a ferry. Or extension of our current super highway network. Use your personal transport machine after arrival. In most of the USA when traveling outside the dense urban areas driving a automobile is the preferred form of transportation. It would make the world a smaller place much like how cars and paved roads did 100 years ago. If we could hyper transport our vehicles at large chunks of distances say 300+ mile integers. I could only imagine this future.

Freight shipping would greatly benefit. Build a freight tube only across the US mainland. Amazon Prime? Same day delivery.

Re: Hyperloop

#782

That capsule ( http://images.bwbx.io/cms/2013-08-12/0812_Hyperloop_605.jpg ) looks like a claustrophobic's nightmare. Otherwise very, very cool.

I'm not claustrophobic, but this image ever so slightly terrified me: http://i.imgur.com/lGD9bUP.png I have to wonder, would making the capsule the size of a small subway car completely destroy the economics of it?

It's no so different from lying in a bunk bed. Isn't it great to have a half hour nap during morning commute?

Re: Hyperloop

#783
post #294
post #231

The main reason why air travel continues to be the most practical, cost-effective means of high-speed transport is that the politics involved in connecting two points with a transit system are enough to make you lose faith in humanity. Take for instance, the DC metro system. There is an expansion underway to extend the system west to Dulles Airport, about 30 miles or so from downtown DC. A huge project, no doubt, but…

Plus Airtravle could be made 10x better without all that usless security shit. I fligh often from Switzerland to Germany and most of my time is spend standing in one line or another on the airport. I see no reason that boarding a plane cant be as efficent or almost as efficent as getting on a train.

Because you can't crash a train into a skyscraper.

I don't know if that's a good reason, but that's the reason.

Re: Hyperloop

#784
post #591

Earlier quoted context omitted.

Sounds vaguely like maglev a couple of decades ago. It too was a neat idea on paper.

Are you guys serious? https://en.wikipedia.org/wiki/Maglev#Operational_systems_ser... Linimo, Shanghai, Daejon, and then all the test tracks, e.g. the transrapid in germany... Maglev is reality now . It simply happened to be built in China, Japan and South Korea rather than in the US.

It's got three short (1 km, 9 km, 30 km) deployments around 40 years after work first started. Are you saying that's the kind of deployment record Musk would like to see for his wundertechnology?

Re: Hyperloop

#785
post #728
post #591

Earlier quoted context omitted.

Sounds vaguely like maglev a couple of decades ago. It too was a neat idea on paper.

I take it you've never travelled between Shanghai and its airport?

No, indeed I haven't. I take it you will consider a 30 km line built 40 years after the idea was first conceptualized to be a success for Musk's technology as well? Should do a lot to relieve the I-5, certainly!

Re: Hyperloop

#786

Earlier quoted context omitted.

I don't have a point really, I'm just saying this was a publicized ballot measure at the time and not carried out against the voters' will. And as I said in above comment, the $9.95 billion was for the initial bond issuance. The estimate on the ballot was $40 billion versus the current estimate of between $98.5 billion and $118 billion.

> The estimate on the ballot was $40 billion versus the current estimate of between $98.5 billion and $118 billion. The estimate from the current Business Plan is $68.4 billion, not "between $98.5 and $118 billion."

They call it a "Business Plan"? That's rich!

Re: Hyperloop

#787
post #643

Earlier quoted context omitted.

> CA HSR replaces/upgrades two metropolitan rail systems (Caltrain/Metrolink) in addition to connecting SF (as opposed to Oakland!) and LA, requires no R&D, is supposed to handle significantly greater ridership, has detailed cost estimates which include things like take into account electrification costs (because it does get cloudy), support facilities (because there is maintenance of these cars), administrative buil…

To be fair, Oakland is a much more sensible location of the initial terminal for any rail system. It's very well-connected to SF, has a complete lack of powerful, moneyed NIMBYs, and it would be easy to punch the line through to SF once it's proven.

Sure, I'd grant Oakland. The line is shown ending roughly near Bay Fair station, an 18 minute BART ride from central Oakland, but perhaps that's still a good compromise. And North Valley? People in this comments thread were saying they'd rather take a flight from Burbank airport, but the train ends even further from central LA.

But more to the point, it's costed through the straightest, least dense, cheapest part of a "SF to LA" route. It's shown with 3 km of tunnel west of Dublin and you'd need at least five times more to get to usefully located stations. This isn't how real infrastructure projects are estimated unless you're purposefully trying to arrive at a low cost estimate.

Re: Hyperloop

#788
post #727

Earlier quoted context omitted.

Because it's per unit of time. The faster you go, the higher throughput you'll have.

The frequency already accounts for the time component. (People/Car)*(Car/Hour) = (People/Hour) = Throughput At a constant frequency and higher speeds, you will simply have less trains on the track at the same time.

Yes, I guess you're right, but the maximum frequency is bounded by vehicle length and speed (you can't have a vehicle pass every thirty seconds if it takes more than thirty seconds for a single vehicle to pass a given point).

Re: Hyperloop

#789
post #722

Earlier quoted context omitted.

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 res…

Ah! Note that the pods are far lighter than trains, being more like a lightweight aircraft. This would reduce the effect considerably.

Vibration from trains is proportional to the unsprung weight of the vehicle (basically the axle, wheels and traction motors) rather than the vibration of the whole vehicle (which is isolated by the primary and secondary train suspensions). For a heavy rail transit vehicle (NYC transit, MBTA Red Line, CTA vehicle, etc), you're talking about 2,700 kg. I don't have numbers handy for HSR trainsets.

Re: Hyperloop

#790

Earlier quoted context omitted.

Can you name any new major civil engineering project in the US in the last fifty years? New San Francisco Bay Bridge. (No, it's not a refurbish -- it's a completely separate bridge with a separate design to replace the existing Eastern span.)

This one: http://en.wikipedia.org/wiki/Eastern_span_replacement_of_the... It only supports my point. It's 2.2 miles long. Construction started in 2002. It was supposed to open in 2007. It will not open until the end of this year. Total cost is currently at six billion. The Hyperloop is 400 miles long, will be built in seven years and will cost six billion. See my point now?

Yes, and when the new Eastern span of the Bay Bridge was proposed, it too was cheap and fast: less than $1B. The dramatic difference in the actual cost has a lot to do with the mayors of nearby cities pushing for a much fancier and complex design, and to a sudden spike in demand for global steel and concrete.

Trying to compare the actual cost of actual projects with the first projected cost of an ideal, untested project is a bit silly, don't you think?

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