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Hyperloop One to shut down

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Re: Hyperloop One to shut down

#331

Post by otabdeveloper4 »

giraffe_lady wrote: post #268
diebeforei485 wrote: post #256

The original Hyperloop paper had a lot of gaps. How does the thing move in low speed until it's fast enough to have aerodynamic lift? Does it use wheels? I don't think the paper talked about it. You do need a good business model and a solid technical foundation. Hyperloop needs a lot of technical work still. Arguably this was also true of SpaceX in the early days, but Elon (and the team he assembled) could execute be…

What mars colony. We're not even within striking distance of a manned trip. Whatever we do after that is so far out I don't think anyone can responsibly assert what it will require.

Mars is the least useful planetary body in the Solar System.

Anybody that is trying to sell you on Mars colonization is selling you a children's cartoon, not a serious project.

Re: Hyperloop One to shut down

#332

Post by stephen_g »

mchusma wrote: post #57

I loved the hyperloop concept, but it felt like the company was too early. The real problem that needs to be solved first before this is viable is "cost effective tunnels". Only once you have those, does adding a vacuum and accelerating make sense. I think Musk believed this as well, which is why he floated the idea of Hyperloop (pun intended) but bankrolled the Boring Company. I think another 10 years of tunneling i…

The problem is that there isn't much more we can do to bring down the cost in tunnelling - there has been incentive for many, many decades to get the cost down to the minimum possible, and that's basically what happened. New materials and things might make small improvements going forward, but it's an extremely mature industry.

That's why the Boring Company hasn't made any progress on this grand vision - they seemed to set out by assuming there were easy wins to be had (seemingly not consulting any actual experts in the field), and then there just... weren't... Basically the only thing they have been able to do is to make smaller tunnels that lack any kind of emergency egress - which is kind of important in real mass transit systems where people would rather be able to get out if there was a fire.

Re: Hyperloop One to shut down

#333

Post by diebeforei485 »

stephen_g wrote: post #305
diebeforei485 wrote: post #266

Earlier quoted context omitted.

I didn't watch the entire 28 minute video, but I did watch the first part and the creator has a misconception that you share. It's key to understand that the Hyperloop concept uses low pressure (around 100 Pa), not a vacuum.

To anyone who works with vacuum systems, there is no "full vacuum", it's always some level of partial vacuum. The challenges are very similar, just the incredible amount of energy that would be required to pump down and maintain that partial vacuum such a huge volume would be slightly less massive.

I don't think energy for air pumps is anywhere near the biggest problem for Hyperloop. There are other far hairier engineering challenges. That said, the efficiency of pumps is not at all linear with air pressure - 100 Pa is significantly better than near vacuum.

The other misconception here is the assumption that the entire length needs to be maintained at 100 Pa. This is not necessary. Having a pressure gradient is fine because it isn't going fast near the terminals anyway.

Re: Hyperloop One to shut down

#334

Post by zizee »

marcus_holmes wrote: post #313

I thought the point of Hyperloop was to head off the upgrading of Californian railway systems? Created and Hyped by Tesla's owner because Tesla needed Americans to stick to buying ever-more-expensive cars. So, its purpose is done now and it can retire gracefully. Or am I being too cynical?

The scuttlebutt was related to the Californian high speed rail project. Would that really take a significant number of cars off the road? And what was the expected completion date? My gut says that it would have an inconsequential impact to Tesla, but I'd be interested if people have numbers that make this theory hold water.

Re: Hyperloop One to shut down

#335

Post by Ekaros »

MBCook wrote: post #251
bobthepanda wrote: post #225

Earlier quoted context omitted.

Also as a practical matter, a lot of systems stop running to discourage traveling; the underground may be safe but you still have to travel on the surface to your final destination

Subways work well, but I have a hard time seeing people travel long distances such as between metro areas knowing their entire journey would be underground. Maybe people would get used to it. I don’t know. I was only thinking of freight really since it doesn’t matter.

There are two areas where such tunnels make sense. You are either going underwater or you are going through mountain. That is you need to it to go through an obstacle.

For rest, over ground or above ground is preferred.

Re: Hyperloop One to shut down

#336

Post by k1t »

otabdeveloper4 wrote: post #331
giraffe_lady wrote: post #268

Earlier quoted context omitted.

What mars colony. We're not even within striking distance of a manned trip. Whatever we do after that is so far out I don't think anyone can responsibly assert what it will require.

Mars is the least useful planetary body in the Solar System. Anybody that is trying to sell you on Mars colonization is selling you a children's cartoon, not a serious project.

As someone who is not at all well versed in this area - this surprises me.

Surely if there is anywhere in our solar system we have a chance of successfully colonizing, Mars is it.

It seems like the obvious first step. Where would you recommend?

Re: Hyperloop One to shut down

#337

Post by heads »

whywhywhywhy wrote: post #261
louthy wrote: post #247

Earlier quoted context omitted.

London's Crossrail (Elizabeth Line) is probably a better example of the cost of a modern tunnelling project (at scale) [1] https://en.wikipedia.org/wiki/Crossrail

Keep in mind it also has to navigate its way around what’s under London which is a lot more complex than most places, considering it’s full of tunnels, Victorian sewers and mass burial pits. Less issues if there’s little down there to begin with. Although personally I don’t see why America can’t just build a train like a normal country.

Indeed, if there are administrative overheads of constructing in built up areas then it would be important to compare with a major highway building project also done in or near a built up area.

I’m still left wondering though, in the open countryside, what the complexity (and cost) comparison is between laying down a mile of freeway and boring out a mile of tunnel. It feels like tunnelling is hard and complicated, but so too is making millions of magic coloured tiles that are all connected to each other so we can see each others cats and, very rarely, make phone calls.

Re: Hyperloop One to shut down

#338

Post by inferiorhuman »

dangus wrote: post #226
dougmwne wrote: post #201

Earlier quoted context omitted.

I’ve slowly lost my innocence when it comes to public transportation in the US. At this point I can see that 95% of the country is absolutely locked into low-density single occupancy transportation at least till we invent sky cars. We have trillions in sunk cost that covers nearly every road, every home and every business in America. We will never, ever be Europe.

The Netherlands had a very similar problem and made very simple and inexpensive changes to roadway planning. For one thing, I think a lot of American suburbs could be way more bike friendly if people just had a safe path to ride in. We are talking a half a lane worth of pavement. Another thing is that this isn’t all or nothing. Still owning and perhaps needing a car but reducing the number of trips per week is a win.…

A lot of American suburbs would be safer if they had sidewalks for people to walk on.

Re: Hyperloop One to shut down

#339

Post by joecool1029 »

dangus wrote: post #223
standardUser wrote: post #195

I think we should accept that, at least in the case of the US, most future transit infrastructure will be built on existing roads. Every other options is an order of magnitude more expensive. Plus, we have so many roads! If we didn't use them it the most inefficient way possible - cramming them full of giants cars for single people who also happen to be terrible pilots - we could get a ton of bandwidth out of them. A…

Incorrect. The US is made up of a huge swath of towns and cities that wouldn’t even exist without railways. https://vividmaps.com/railroads-in-america/ You say that every other method of travel is more expensive…but that doesn’t really pass the sniff test, does it? The Big Dig in Boston adjusted for inflation cost more than New York City’s “world’s most expensive stretch of subway.” The California high speed rail pro…

> Which country’s train system kills 30,000 people annually?

India's getting close: https://timesofindia.indiatimes.com/city/lucknow/every-hour-...

Re: Hyperloop One to shut down

#340

Post by zizee »

otabdeveloper4 wrote: post #331
giraffe_lady wrote: post #268

Earlier quoted context omitted.

What mars colony. We're not even within striking distance of a manned trip. Whatever we do after that is so far out I don't think anyone can responsibly assert what it will require.

Mars is the least useful planetary body in the Solar System. Anybody that is trying to sell you on Mars colonization is selling you a children's cartoon, not a serious project.

What is a better candidate for colonization?
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