Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Hyperloop: Pipes of Fancy

economist.com

Post reply on HN
Print view View original

231–240 of 322 posts

Re: Hyperloop: Pipes of Fancy

#231

Post by _ph_ »

jcranmer wrote: post #94
vwat wrote: post #87

Earlier quoted context omitted.

It’s not legit at all. I’ve always been a fan, and all his busted videos in the past featured one very important feature: the violation of thermodynamics. He always showed why a product was physically impossible. But he doesn’t do that with a hyperloop. And ultimately, if you see through the repetition and downright nastiness, you see that his argument is essentially “hyperloop is very expensive, it would be unsafe a…

The problem with criticizing hyperloop on technical grounds is that there often isn't even enough substance to really criticize. There are several designs, which only really have "you put it a vehicle in a vacuum tube and go zoom!" in common--and even then, there's contention about vacuum. So the only way you can really criticize it is on gadgetbahn grounds: it's shiny new technology [1], that's safer, cheaper, faste…

Perhaps then wait with critisizing the hyperloop on technical grounds until there is enough with substance instead of making up fake technical facts? Currently the Hyperloop is basically just a concept and a couple of startups which are not connected to Elon Musk in any sense. Of course, as with any new startups, there is a lot of marketing and little substance. And yes, as with any startup in a completely new technological domain, one should be highly sceptical about their success chance. These kind of tech startups do have a huge chance of failing indeed. If it were trivial to pick up a completely new technology and bring it to the market successfully, everyone would be doing it. Also, there is quite a bit of shady business going on. A lot of startup companies are run just to finance large salaries, while the investment money lasts and to vanish after investment money ends[1]. But all of this is not a valid technical criticism of the hyperloop. There are certainly valid points to be made against the feasibility of the concept, but then these points should be made and not artificial ones invented.

1: I could once watch this from close-up. As a grad student, I was involved in optical data storage. We were able to store a few gigabytes in a small crystal. This work was financed by a startup company created by a consulting company. This startup would collect money - largely from state research investments to match to the private money promised to be invested by the consulting company. This did finance our work for some years and paid a couple of salaried employees of the startup - related to the consulting company. When the public investments ran out and no third party investments had arrived, the startup would fade away. And with that the project in spite of what we had achieved so far.

Re: Hyperloop: Pipes of Fancy

#232

Post by _ph_ »

brunoqc wrote: post #3

https://youtu.be/2h6Cz4hwuEI How legit is that video and YouTuber?

A very bad piece. The video uses the very techniques of showing shiny renders to make its point it critisizes. Also mixes up a lot of facts and pretends things are in a context which are not. While there is valid criticism of the Hyperloop concept, this video certainly isn't.

Re: Hyperloop: Pipes of Fancy

#233

Post by LordHeini »

All this stuff does not solve the simple problem of moving the people to the rails to begin with.

Living in Germany, i can get onto an ICE and tear through the country at 280 km/h at any time (usually with huge delays though).

But often people still don't, for a few reasons which will be true for any technology, replacing the standard trains.

One reason is, that transportation is always a door to door problem and if the transport from and to the train stations sucks, the whole system will not be used.

Who wants to deal with changeovers from buses to trains all the time, if those have horrible working hours, constant delays or long waiting times?

The whole public transport system must be comprehensive, always available, reliable and fast. Being partially fast solves nothing.

Re: Hyperloop: Pipes of Fancy

#234

Post by qayxc »

manigandham wrote: post #136

The vac-train concept is from 1799. Maglev tech is decades in production. I remember a Discovery Channel show 20 years ago about trains traveling 5000mph through tunnels at the bottom of the ocean to cross continents in an hour. Hyperloop is fantastical renaming of old tech without solving any of the fundamental problems of economy, geography, energy and politics. We're capable of building incredible projects if only…

Please remind me again how a company with a market share of 0.6% [1] is changing global transportation?

It's fascinating to me how people seem to vastly underestimate the actual volume of the global car market while overestimating the impact of unicorns.

In order to even make a dent in the global market, getting into the double digits would be required.

Even in the market "dominated" by Tesla (e.g. plug-in EVs), their market share is a combined 16.6%, meaning more than 83% of EVs are made by other companies [2]...

Tesla is to the car market quite literally what Apple is in the desktop PC and smartphone markets - a "dominating force" with a tiny market share in the global market.

[1] https://www.best-selling-cars.com/international/2019-full-ye...

[2] https://insideevs.com/news/396177/global-ev-sales-december-2...

Re: Hyperloop: Pipes of Fancy

#235

Post by bildung »

aaron695 wrote: post #131
AlexandrB wrote: post #9

This is evergreen when talking about Hyperloop: http://www.cat-bus.com/2017/12/gadgetbahn/ The problems with building this have nothing to do with technology but with right-of-way, investment, and politics. If those factors were solved, we'd already have high-speed rail in places where Hyperloop has been proposed. The fact that we don't says that Hyperloop is unlikely to be feasible as well.

The entire point of the Hyperloop is to get around right of way and politics. That is it's design. That is exactly what Elon is doing. You might argue it can't do what it's setting out to achieve, but this has never been a technological solution. He's designed a technology to fit with current societal processes rather than the old, get society to accept a technology.

But right of way extends underground in the US - literally "all the way to hell"? https://en.wikipedia.org/wiki/Cuius_est_solum,_eius_est_usqu...

How is this something that can be solved with the yet to be invented new TBM?

Re: Hyperloop: Pipes of Fancy

#236

Post by ricardobeat »

Alupis wrote: post #82
ricardobeat wrote: post #79

Earlier quoted context omitted.

You should take a second look at that. Average wages in China are $12k/year, only a third of the US, but higher in the industrial areas, and in terms of purchasing power it has surpassed every other country long ago since everything is so cheap at scale. They have half a billion people in the middle class.

When you are directly comparing how much something cost to build, such as a mile of track, in USD, Purchase Power doesn't matter, does it? This is what the Parent post was asserting. China builds a mile of track at half the price because they literally pay their people half the price (or less). It doesn't matter that their local Purchase Power might be greater. Taking it a step further, the Parent was comparing a mil…

> It doesn't matter that their local Purchase Power might be greater

It matters because it means that the economies are not directly comparable.

You said they can only do that "without paying US prevailing market wages to the contractors." as if that is somehow an unfair advantage. But if their workers don't need US salaries to have a good living standard, because purchasing power is higher, and are not being exploited, where does the problem actually lie?

Re: Hyperloop: Pipes of Fancy

#237

Post by bildung »

ponker wrote: post #54
shajznnckfke wrote: post #41

Earlier quoted context omitted.

Ok, so how is this cheaper than high-speed rail in a tunnel? It seems to me that hyperloop is high speed rail with the addition of a vacuum, which gets you higher speed. The additional requirement of a giant vacuum tube should make the system cost more, not less. Personally, I’m rooting for Elon Musk to figure out how to make tunnels cheaply with the Boring Company, so we can take that tech and use it to build a bunc…

It uses a much smaller tunnel.

Which means the throughput per tunnel is more expensive, right? A tunnel with a half diameter will have a quarter the throughput (i.e. the ratio of circle diameter to area). Which is why TBM tech develops towards bigger machines, not smaller ones.

Re: Hyperloop: Pipes of Fancy

#238

Post by temptemptemp111 »

Amazing how unintelligent all of the engineers replying in this thread are... It is objectively true that having all planes in the air flying the same exact path is idiotic. Ditto for fast pods on the ground. Plus take all of the downsides of not having an atmosphere. Plus take all of the downsides of someone being able to shoot a $10 bullet anywhere along the side of this and you have a shock wave traveling the speed of sound that will destroy any pods within about a mile of the hole (and all of the others if they don't have an intelligent emergency braking system).

This whole thing is a joke and anyone who thinks Elon isn't an actor has their head so far up their ass they have no place commenting on the web concerning "space travel" or any related topics.

Re: Hyperloop: Pipes of Fancy

#239

Post by [deleted] »

jryle70 wrote: post #116
kevingadd wrote: post #31

Earlier quoted context omitted.

Are you asserting the space and electric ventures were not funded by taxpayers?

They weren't, if you meant taxpayers subsidized them. Have you seen the hops Tesla has to jump in order to sell cars to consumers, like in Texas or Michigan? NASA is indeed SpaceX's most important customer, but taxpayers in fact save lot of money because SpaceX's offerings are much more competitive than those of other providers.

[deleted]

Re: Hyperloop: Pipes of Fancy

#240

Post by yosamino »

_ph_ wrote: post #225
AlexandrB wrote: post #9

This is evergreen when talking about Hyperloop: http://www.cat-bus.com/2017/12/gadgetbahn/ The problems with building this have nothing to do with technology but with right-of-way, investment, and politics. If those factors were solved, we'd already have high-speed rail in places where Hyperloop has been proposed. The fact that we don't says that Hyperloop is unlikely to be feasible as well.

I am disagreeing with the article. Of course, when designing/selling new train systems, a lot of showmanship and gadgetery are involved, but there are real shortcomings with current train systems which cause people to develop new technologies. First of all: trains are great, there are many places where they perform admirably. Many cities have a great subway network, countries like France, Japan, Taiwan and now China…

> However, there are shortcomings wiht traditional train systems, these new systems try to address. One big limitation for trains is, where to put the tracks. [...] The Boring companie tries to lower tunnel costs by making them less in diameter.Other systems try carts which run on or hang from stilts, reducing the space needed or allowing the train installations to go on top of existing roads.

Which is one of the main points of the article: the limiting factor is not the type of propulsion, but how and where to put the tracks.

Tunneling is expensive. Decreasing tunnel diameter just turns one knob of that system. Emergency access, switching and mergeing systems, and access to the tunnel itself use space and cost money. And if the idea is to just add tunnels to increase capacity, then that is probably more expense than building a proper train system with higher passenger density in the first place.

Trains that hang from stilts still need the stilts to sit on the ground somewhere.

Trains that sit atop of roads are limitied in their speed, by the traffic these roads where originally designed for. The curves might not be suitable to go around at high speeds.

You can't also just increase speed - acceleration and deceleration forces as well as the forces acting on a whatever kind of pod on whatever kind of track are physical limitations that affect passenger safety and comfort.

All these ideas improve on some small aspect of the system as a whole, but they do not solve the fundamental difficulties inherent in designing public transportation - they do the job, but not without the same real world problems that we have with traditional rail.

Autonomous operation for increased frequency might make some sense, but then that's something that can probably be retro-fitted to existing systems, and has little to do with the propulsion system in use.

... and I know of at least one urban public transport system where the limiting factor for increased frequency is ( apart from the issue that six train lines share one bottleneck track ) the time the doors take to close safely... not something I would have had on my radar as being a problem.

Post reply on HN