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Transport Expert Insists 'Don't Dismiss Wacky Hyperloop'
DavidGilbert99 writes "Since Elon Musk announced the details of Hyperloop earlier this week, we've seen a number of experts debunking the technology involved, but at least one is more upbeat about the possibility of 600MPH train travel. Speaking to Alistair Charlton at IBTimes UK, professor Phil Blythe from the Institute of Engineering and Technology said: 'My gut feeling is, don't dismiss it out of hand just because it sounds a bit wacky,' adding 'You're always going to have long distance travel, and if there was something that could replace air travel between cities and hubs, and is low carbon [with] low energy requirements, it make sense to explore it, it really does.'"
See John Oliver's take on it.
(He actually pokes fun at the media coverage rather than at Teh Loop itself.)
Sheesh, evil *and* a jerk. -- Jade
It is a loopy idea, but not fundementally unsound in any way.
Every aspect of it, from the induction motors, to the earthquake proofing to the aerodynamics to the solar power is all well understood.
The difficult bit is really the engineering on a large project and developing all the parts and actually building the thing. I wouldn't trust most people with it and the usual suspects for government contacting would surely make a massice hash of it and cause a 50x budget overrun.
But that's nothing to do with the project per-se. Musk does have the kind of track record showing he can pull off big, complex engineering projects which are generally regarded as difficult and expensive applications of existing tech. Not only pull them off but do them well, quickly and cheaply.
So please, don't bring up arichair engineer objections to the design without first reading that big, long document which covers most of them and actually providing some reasoning.
SJW n. One who posts facts.
That project was reported to be both technically and economically feasible despite the handicap of having to tunnel all the way through granite. Apparently the project died for lack of interest and political will to see it through.
So, what people refer to as "Elon Musk's idea" really isn't new and also isn't nearly as wacky as some people seen to think. The thing that Elon Musk seems to be adding is marketing and PR. Perhaps that will make the difference.
Science Fiction and reality. I like the idea of Hyperloop, but what happens with a 600mph crash? How do you elevate tubes across thousands of miles and through Cities without A) creating curve that have g-forces too high to survive a 600mph turn or B) becoming so incredibly expensive for right of access rights that it becomes impossible? With cars holding a limited number of people, how do you address the mass populations? Jets carry hundreds and they're routinely overbooked. How does economies of scale fit in? Oh, I'm sure the realities could be vast on this idea. .. Hats off to Elon though, because there are those that do and there are those that do not. If he didn't do, we wouldn't have Tesla showing how electric cars can work.
Select from tblFriends where interesting >= 4;
I don't get it.
Sure, it sounds fantastic, but isn't this pretty much the same as a system proposed way back in the 50s?
I'm pretty sure I saw that in a reprint of an ancient Popular Mechanic.
(Maybe it was Popular Science, but was that one even being printed in the 50s?)
Besides that, he's not putting any money into it, and he doesn't have blueprints or anything, just an idea. Science Fiction writers do that level of work all the time with new ideas.
On a technical note, what about shifting of the ground, especially with earthquakes and the like. It probably only has a fraction of the tolerance to that which railroads have, especially at the speeds he's mentioning.
What will he say next week to be in the news ?
Ad hominem attacks on Phil Blythe
Dismissive comments about the project from people who have no real understanding of the topic
Supportive comments about the project from people who have no real understanding of the topic
Some jokes
There, I've saved you the trouble of reading the whole thread!
That way land is free and the tube can be made totally standard and mass produced. Anchor it to the sea floor at a depth of 50 meters. That would make it easy to run between LA and SF, and many other routes would become easy too.
http://michaelsmith.id.au
December 17, 1903, Kitty Hawk, North Carolina:
Orville Wright: In 50 years time we'll be putting hundreds of people into metal tubes and hurling them through the air at hundreds of miles an hour by squirting hot air out the back.
Transport Experts: What a stupid idea! There's no way that would work!
I'm pretty sure I saw that in a reprint of an ancient Popular Mechanic. (Maybe it was Popular Science, but was that one even being printed in the 50s?)
Popular Science in its modern form was first published in 1915. Popular Mechanics, 1902. In its prime, Popular Science published countless projects for the amateur scientist, radio hobbyist, model maker, craftsman and mechanic. along with some very good reporting on sciences, technologies, medicine, the military and so on.
test freight containers first for at least 5 years. then only human trials.
nuff said
Instead they are planning on sinking 10x the amount into high speed rail that won't compete with current airline times and prices. This is as much a call on sense of the high speed rail programme as it is the proposal itself.
You may think me a tired, old, cynic. I'd have to disagree about the tired bit.
Actually the whole idea is that it is a profitable venture, one that's orders of magnitude cheaper than a conventional rail link over the same distance.
No kidding!!! What do you say at this point?
There are a lot of good ideas here, and there's no reason that this would be an engineering impossibility. The problem is just a risk ratio.
This will cost billions even if everything had been ested. there will be some ideas that work on paper but in practivce need to be re-engineered. this happened with the Space Shuttle and even the Shinkansen; where the basic technology was already well understood.
when they haven't successfully built a high-speed rail line (and don't try to pass of the Acela Express as high-speed rail). Good luck dealing with the noise pollution. Has he even ridden on the ICE and seen the efforts required to reduce noise pollution?
An actual transit engineer crunches the numbers here:
http://greatergreaterwashington.org/post/19848/musks-hyperloop-math-doesnt-add-up/
And finds that while the journey for individuals may be faster, the system as a whole would have one-tenth the capacity (i.e., the ability to move people in numbers) than the planned high-speed rail system. You could solve this problem by building 10 times as many tubes, of course, but that would eliminate the 90% cost savings Musk is touting.
The radically reduced travel times vs. HSR are also deceiving. The maps Musk released show the system travelling from the fringes of the Bay Area to the fringes of the LA area, because it's hard/expensive/impossible to get land for the straightaways you'd need for the project within densely built up urban areas. To get from San Francisco to the hyperloop station, or from the hyperloop station to downtown LA, you'd have to switch to local transit or drive, which will double or triple travel time. Not coincidentally, must of the construction and expense that adds to HSR's very high price tag will come in SF and LA urban areas, since that system goes from downtown to downtown.
And if I look in everyone's ears, I can pull out enough quarters to pay for it! It used to work for my uncle buying ice cream!
I'm using this as inspiration for my new transit technology: giant rubber band sling.
You do realise this is in a closed tunnel, right? I'm preeetty sure it'll be a whole heckuva lot quieter than a train, a plane or a road for that reason alone.
Should read 6000MPH travel, since after all he's claiming New York to LA in 30 minutes. And, that's average, so accounting for the need to slow down at times, peak speeds probably need to reach closer to 10000 MPH in the Plains states.
It's always the political, economic, and/or legal issues that kill these kinds of projects:The tech may be sound, but if you have your investment locked up in frivolous lawsuits, or bureaucratic red tape, your investors will, sooner or later, desert you: they want a return on investment, not "real soon now", but now. . . . But in the end, I suspect it's pure economics that will stop the Hyperloop, at least as initially described between San Francisco and LA. I'm not convinced there is sufficient traffic to support the costs and charges as foreseen. Most especially telling is that the load/fare estimates of 840 passengers/hour@$20/passenger. Assuning load is constant over the entire 24-hour period of the day, and there are no disruptions, you're only taking in a bit over $147 million in revenues. Maintenance, cleaning, operations all cost money, and the more likely pattern is only peak passengers during part of the business day. So I conclude, nifty idea, but economic fail. . . .
In the 1970ies when I way just a boy, I found an "old" book from the 1960ies. They already discussed the same concept together with maglev and other high speed ground based transportation systems. As of today all these high speed "trains" are very expensive and bring little benefit to populated areas. A ground based vehicle which is as fast as a plane is most likely technical possible, but the infrastructure cost would be extreme. Therefore, it would only be an option for short distances. At short distances that much speed makes no big difference.
BTW. the Chinese have developed trains with similar speeds, which are able to run that fast. If they had worked with higher precision, the trains could use that speed in a reliable way.
Has been used in PTT (Pneumatic Tube Transport) for 140 years.
Everyone is debunking Elon's idea as unintelligent, I mean it's not like Elon's a rocket scientist or anything. Oh wait, he is.
Land acquisition isn't as big a deal as some have made out. Back in the 80's San Jose's freeway building days were declared over and then in the 90's Hwy 85 got built from one end of Silicon Valley to the other. If there's a political will and capable leadership, land can be acquired.
My concern is the pylons. His drawings show them as passive entities. That simply won't work in California where the land shifts continually. Sometimes it's gradual as in fractions of inches each year and sometimes its catastrophic as in 27 feet in a few minutes. The whole state is nothing but flotsam that's accumulated over the ages and it's still shifting.
The section through the valley where he proposes to run full speed goes right by Coalinga, the site of of a small quake in 1983. The quake was large enough to throw houses off their foundations because no one in Coalinga thought they lived near a fault and so didn't build accordingly. A hidden fault directly under the town disabused the residents of that notion.
The problem isn't insurmountable. The Alaska pipeline was engineered with quakes in mind and it survived a major quake directly under its path. The difference here is that oil isn't moving as fast and so the solution was less expensive than what would be required to accommodate a train full of people going 700 mph. The oil doesn't care it's being shoved left, right, up and down. People do care.
Making the pylons able to adapt to the ground underneath them shifting fast enough so the train passengers don't even know there was a quake will be expensive. Making the tops adapt to wind gusts the valleys are susceptible to will be expensive.
I wouldn't be surprised if the expense was multiples of Musk's guess. If this idea is to go forward, that expense will have to factored into the construction and operation estimates.
Blythe believes the long term success of Hyperloop will lie in its ability to be powered entirely by solar panels. "The compelling argument today is that the energy to run this could be generated from renewable resources, so the energy cost and the CO2 emissions are low - that probably gives it a bit more of an interesting argument whereas 15 years ago we didn't care about stuff like that.
But it far cheaper to electrify a conventional train track. And far cheaper to install just solar panels on top of all highways and rail tracks. In fact if we put a "roof" over all the highways in the northeast and install solar panels on them, the savings in snow removal costs in winter and the electricity generated in summer could pay for the whole project. Putting gables over highways and directing the snow to fall on the sides instead of on the lanes is a far cheaper project than this.
The home construction industry still reeling from the 2008 financial shock could use a shot in the arm. Regular conventional structures, gables and trusses, oriented to face the South, over I-90 between NewYork and Boston. Why not? We shoveled 800 billion dollars to the greedy banksters in just three months in 2008. A steady 10 billion dollar a year to put roof over highways is probably a better idea.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
Ok,,train on a magnetic rail,,,that's not new by 30 years +, there was some model shown (small model) back when i was 12 years old, so it's not unrealistic,,costly i would think, but if it works on a model, it will work on human scale.
I expect us to think about it for ages and let the accountants pour cold water on it... It will then be forgotten for quite some time. Then China or Russia will build one... China already built a maglev. With China being #1 solar panel producers currently, the fact that land belongs to the government so they can build wherever they want (and violently force people who refuse to move) as well as billions of depreciating dollars held in reserve and engineers as their one party politicians rather than lawyers (like USA and UK)
"On that train, all graphite and glitter. Undersea by rail. 90 minutes from New York to Paris, well by '76 we'll be A-Ok."
-- Donald Fagan
No, no, you're not thinking; you're just being logical. --Niels Bohr
What is the point of a few professors and engineers saying it's interesting, that is not at all relevant.
The question is simple: Does it make a lot of money? If so should we or should we not further exploit current, slower, higher carbon footprint and more financially lucrative options.
Would it be a great improvement over current forms of travel? Of course.
Would it be a great way to show the world the US is actually investing in something cutting edge? Of course.
Would it eventually make its money back? Most likely.
Yet, I can assure you they will not build this Hyperloop train any time soon if ever.
We live in a society where money is everything. Advancement in technology only comes in second place when it comes to weapons in every other field we can be lucky if its importance is even in the top 10.
Ohh well.. enough evil conspiracy talk...
I hope to ride the Hyperloop train at sometime in my life and even though I expect to live at least 50 to 60 more years I somehow doubt I will even see it in action on TV.
LOL. Since there is no such thing as man made global warming, what difference does 'carbon' make, and why do idiots keep referencing it, like some religious mantra?
Take I-80 coast to coast. The big challenge is staying awake through 1000 miles of corn, but you'll start to appreciate just how much of it we grow.
That's the beauty of 800mph travel. You only have to look at the corn for an hour and fifteen minutes, then you get a change of scenery. New York-Cleaveland-Chicago-KC-Denver would be a nice route to have, with maybe a southern spur St Louis, Memphis, New Orleans, along with a second western route from New Orleans through Houston, San Antonio, Touscon, Pheonix, to LA. Add a northern routhe Chicago-Minneapolis-Bismarck-Billings-Misoula-Spokane-Portland, hooking up to a west coast link from Vancouver to San Diego and you have a pretty well connected country. Obviously speeds would have to be slower in the rockies, barring expensive tunneling projects, but it would still beat air travel between most of those cities.
The Future of Human Evolution: Autonomy
the thing is in a round tube, the centre of mass of the car is below the centre of the tube, it will always rotate such that the centre of mass is pushed to the lowest energy point, so a passenger would only feel vertical G, like sitting in a fast vertical elevator. 2G is a very tame roller coaster, or a fairly brutal elevator. You would certainly feel it, but it wouldn't be that uncomfortable, especially in those fully supportive seats.
1) Initial cost
2) Maintenance costs over time, particularly if there are economic upheavals in the USA's or the world's economies.
3) Energy costs over time. While petroleum may not be what this thing uses for fuel, I guarantee you it's what gets' the thing built, and maintained for the forseeable future. FYI, petroleum fuels, even as they temporarily dip in price with the economy, are on a long term upward trend, spiking wildly when oil price feedback hits.
4) The possibility that may not have a single, continent-spanning nation state spanning North America within the next few decades.
Cool engineering idea, but this isn't the 1950's. We didn't just win a war and have industrial overcapacity looking for something to do. We are no longer sitting on an ocean of cheap, high net energy oil (Natural gas, while nice to have, isn't really going to cut it as a substitute. Sorry), and frankly we don't have the political or national will to do this sort of thing anymore.
Please do not read this sig. Thank you.
The difficult bit is really the engineering on a large project and developing all the parts and actually building the thing.
Nope. The most difficult bit is getting the right-of-ways. Presuming the design actually works (not a trivial presumption) the construction shouldn't be terribly hard once the financing and right-of-ways are obtained. But getting those right-of-ways is a hugely difficult problem and will account for much of the cost of such a project.
Levy is not dismissing it "because it sounds a bit wacky." He's dismissing it because a realistic analysis shows that it is wacky.
If a thing is not diminished by being shared, it is not rightly owned if it is only owned & not shared. S. Augustine
I'll note that it's generally more efficient on fuel to fly than to drive as well. Especially the fewer passengers you'd have in the car. Stuffing so many people into a single plane makes the amount of fuel used actually fairly low, and as long as the trip is high enough, they spend much of it up high enough that air resistance is less despite the speed.
That's why you want to evacuate the tubes - lower air resistance, plus the low rolling resistance of rails(much less maglev), allows you to get the air resistance planes get, without the expense of getting to the altitude.
Something ground based that's fast enough to compete with air travel on speed, that allows you to shift more people between hubs without using aircraft would take a lot of strain off of the hub airports.
I don't read AC A human right
I take it seriously enough to be concerned about safety.
Terrorists like to pick high profile targets, like airplanes, so that a LOT of people know what they did. This leads to people questioning why they did that, which, hopefully (to them) will lead to political support.
A super expensive, super modern bullet train traveling at super high speeds, generating a lot of energy is a JUICY target.
Especially since all a terrorist has to do is to sabotage one piece of track to send that train flying. It may not be practical to monitor every single mile of track.
Given that this system rides on 1mm thick air bearings inside of a smooth tube, I don't think that noise pollution is much of a concern on the outside of the tube. The air inside the tube is at roughly 1/1000 of atmospheric pressure, so the sound doesn't propagate all that efficiently inside of the tube. The only sources of acoustic noise is the vibration of the intake compressor at the front of the pod, transmitted through the thin air bearing cushion. This is relatively easy to mitigate, since rotating machinery running at a constant speed is about the easiest thing to deal with in terms of NVH (noise, vibration, harshness). An internal combustion engine is way harder to tame, and even that has been pulled off successfully :)
The tube/pylon system will of course be subject to excitation from the radial forces by the passing capsules. So far, the significant modes are around 2-4Hz, so that's not a big problem. There will be dampers between the pylon and the tube, those will keep the number of cycles of oscillation "low" (ideally: it'll be critically damped).
A successful API design takes a mixture of software design and pedagogy.
Even better: it's an evacuated closed tunnel, kept at 0.001 bar.
A successful API design takes a mixture of software design and pedagogy.
Slashdot Experts Insist "Dismiss Wacky Transport "Expert""
Your move, professor in the UK who just wanted to latch onto the "Hyperloop" story to get his name out there.
Oscillations and harmonics.
If you've ever ridden BART or the DC Metro, you're familiar with the screech. Sound resonates in tunnels. First, there's the question of whether or not some odd resonance will make things uncomfortable for the passengers. Next, there's the question of whether or not some odd resonance will shudder the car apart. What happens when some minor defect in the tube doesn't catastrophically destroy the car... but it starts vibrating, and the rare air in the tube doesn't damp the vibration but reinforces it?
Things like this have to be tested at scale. It seems like you'd have to commit to building before you test, and if the thing turns out to be the world's largest organ pipe and you can't fix that without slowing it down, well... Ooopsie!
I think it'd be interesting to find an abandoned pipeline, retrofit it, and put some non-human payloads in there first. It's not the same as a scale test; but just put some simple recording devices in there and see what the sound and vibration are like, and whether or not it can be tuned away, compensated, or damped without ruining the speed.
The main issue is how to secure it. It's only feasible if it's medium distance to very long distance. Which means it has to connect densely populated areas while going through sparsely populated areas. The level of security that it would require would be much higher than train tracks because the high air pressure requirement makes it less stable. Securing highly pressurized tubes over hundreds of miles of sparsely populated area might make the whole project less feasible.
Any guest worker system is indistinguishable from indentured servitude.
LHC pumps 9000 m^3 to ~10^-9 atm to insulate their cryomagnets. That's the volume of a 2.4 km stretch of the passenger-only hyper-loop, at a million times deeper vacuum. Now, that they're doing that at CERN doesn't mean in any way it's easy or cheap. And the hyper-loop is still a volume a few hundreds of times bigger, without any compartmentalization.
Thermal expansion is also interesting. Back-of-the-envelope:
1.5*10-5 (thermal expansion coef stainless steel) * 40K (guesstimate max delta-T day/night) * 563*10^3m
= 338m thermal expansion/contraction, or 169m at each end.
They'll want to insulate it or at least shield it from direct sunlight -- which the solar panels will partially do.
A evacuated steel tube. It will have resonances and will ring. Likely at a harmonic of the linear motor frequency.
John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
Linear motor, steel tube. You are ignoring an excitation force.
Critically dampening a 3/16 steel plate (thickness pulled from a dark place) is an engineering challenge. That's a fucking strong spring. Better plan on wrapping it in a foot of 'crete.
John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
I wonder how air travel compares to rail when you also factor in the cost of the required infrastructure. Trains are much more fuel efficient, but laying massive amounts of rail is not cheap.
END COMMUNICATION
He promised 4,000 MPH. 600 MPH is only 15% of the speed of his promise. Why isn't he being held accountable? Why aren't businessmen in the US ever held accountable for their fraud? He is defrauding the public. He should be punished for this fraud.
Laying rail is pretty cheap. Buying land sometimes isn't, but putting a bunch of steel rails down end to end is pretty much the cheapest kind of transportation infrastructure you can build. It's possible sidewalks are cheaper.
Airports are extremely expensive, both to build and to operate. So is air traffic control, aircraft maintenance, inspection, fuel infrastructure, parts infrastructure....
I have friends who fly privately. Even for small planes, the purchase price of the aircraft is about the cheapest part of the whole enterprise.
There are no linear motors. Well, um, yes, there are linear motors, if you look for them with a very good flashlight, that is. They cover about 1-2% of the length of the track. The words used in the fine description of the system are used for a reason. It's a mostly passive capsule, an almost ballistic system, with a compressor in the front of the capsule to provide compressed air to the air bearings and to bypass the plunger-in-a-syringe effect in a cheaper way than merely throwing a bigger tube at the problem. The linear motors reboost the capsule periodically. It will be coasting for about 29 out of 30 minutes. They also apply a force that doesn't give big reactions in the direction of easy to excite modes of the tube walls. After all, the motors push the capsule forward (or pull it backward); they should be symmetrically arranged so that there is no net pitching moment. Thus there is, to a first order at least, no excitation of the serious modes of the tube.
A successful API design takes a mixture of software design and pedagogy.
Only if the said motor is acting in the direction of deflection of the important modes. It so happens, it won't. I'd like not to have to remind everyone that there are, like, um, engineers working on that thing. Presumably with some, like, structural experience with things that are notoriously difficult. Especially aerospace is kinda notoriously difficult, with good, quiet cars not far behind.
A successful API design takes a mixture of software design and pedagogy.
Based on the energy comparison chart, it seems to me that the hyperloop would require energy costs to rise for the investment to become economically worthwhile. Low energy usage is it's main advantage.
These comments are mine; I do not speak for my employer.
Back to electric fields for you.
John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
There's already a lot of HSR in europe, but there's also a need for faster trains, better rail freight handling and roll-on-roll-off HSR (people drive long distances mainly so they don't have to rent at the far end) and HSR is already going about as fast as is practical (the limit is air resistance, not the rails - and most of the air resistance encountered on a high speed train is along the sides, not at the front.). Practical HSR needs entirely new trackways so Hyperloop isn't as disadvantaged economically as one might think and there strong arguments for keeping longhaul rail optimised for freight operations.
It's been said that if there was rail transport between spain and morocco, perishable transport operations would go faster and use significantly less carbon than the current airfrieghting operations - as well as bringing economic benefits to most of subsaharan africa. Hyperloop might well extend itself to this kind of work using freight pods.
Overall, the Hyperloop concept is good, but given the amount of systemic corruption in the american political system, it's unlikely to have legs in our lifetimes. I personally doubt the claims about self-sustaining operations off solar but I'd love to be proven wrong.