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Elon Musk's 'Hyperloop': More Details Revealed
astroengine writes "Entrepreneur Elon Musk revealed details today about his concept for a high-speed transportation system he calls the Hyperloop. After tweeting that he'd pulled an all-nighter preparing for the announcement, Musk told Businessweek that the design could transport people as well as cars inside aluminum pods that move up to 800 miles per hour through a tube. The tubes would be mounted on columns 50 to 100 yards apart, not interfering with land needs because it would essentially follow major highways, such as I-75 in California."
. . . it would essentially follow major highways, such as I-75 in California.
Let the record show that TFA correctly states "I-5". Somebody in Michigan needs to watch his typos.
The problem I see with this is while it's nice to dream about 800 mph travel, I can't imagine that it would be feasible to construct a track or tube that could follow the terrain at that speed and still maintain passenger comfort. If you are building above-ground supports, you don't want them to be 500 ft tall as would probably be required in order to keep the tube straight enough for passenger comfort and safety.
That was the turning point of my life--I went from negative zero to positive zero.
I think it would be a much better replacement for freight trains and trucks. I'm guessing that may be their goal but they don't want to upset the train and trucker unions just yet. I'd say Amazon should get it on this as well to speed up their shipping times and hit their same-day delivery dream.
That's actually a problem past a certain speed. At least in the U.S., they don't allow trains to travel at high speeds in populated areas because they can't usefully stop if somebody walks across the rail. They can't stop because there is very little friction possible. With a closed tube, you don't have that risk, so you can shoot through downtown L.A. doing 250 MPH.
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Can these tubes also be used to carry the innernet?
Who would win this election: Andrew Weiner vs Andrew Weiner's weiner.
It seems like one could deter people from walking across the rails with some sort of symbolic notification device? To not reinvent the wheel, we could reuse the old inventions of "words" on a "sign":
WARNING
TRAINS GO THROUGH HERE
THEY GO REALLY FAST
IF THEY HIT YOU YOU'RE DEAD
EVEN IF YOU'RE DRUNK
or something.
We haven't roped off every cliff in the mountains, even though people die there. We've not even put warning signs on a lot of dangerous things ("WARNING: THIS IS A BEAR. DO NOT POKE IT. IT IS BIGGER THAN YOU. EVEN IF YOU'RE DRUNK.") Why do we need derp-proof railways?
All the /. experts come out of their caves to debunk a paper by a guy that brought us internet payments, commercial space travel, and luxury electric cars.
I love it when simple obvious, and in this case old, technologies blow expensive and complicated technologies out of the water. Let's see, an old pneumatic message system with cars big enough for people. Cheap, easy to build, probably dirt cheap to run and maintain. Wow.
But there is huge problem with this system. Being so cheap and simple there is little room for massive companies to lobby/sell their complicated overpriced technologies. Tubes? How long is the list of companies that could build tubes? Pylons? How long is the list of companies that can build pylons? The train cars are a bit more limited but again not being maglev that list is still pretty long. Land purchases? I suspect that a bunch of insiders had land all lined up to sell.
Then you get other technocrats who don't like that their territory is being infringed. The rail people are probably scared that this might be independently run.
And lastly you get the aviation related interests that are far larger than most people might think. You have the oil refineries who will be unhappy to sell less fuel to both planes and cars, you have taxi drivers who run people to the airports, you of course have the airlines themselves, and you have the airports who will be unhappy to have fewer landings and takeoffs. Plus the no-doubt 50 unions who run the airports among others.
A tube system like this would be pure evil as far as those people are concerned dropping people off right down-town, how dare they.
The one thing I did not see is what the expected magnetic field levels will be for passengers.
Many folks with implanted medical devices are told to stay away from significant RF and magnetic fields. It is possible that the pod could be magnetically shielded enough, but it would be great if he added that info.
Otherwise, I say scrap the Cali High Speed Rail and build Hyperloop instead!
(The truth is that I bet the Casinos would throw in the first billion to build one from LA to Vegas...they dumped $650 million on the Las Vegas monorail).
Common sense would tell you that the earth is the center of the universe and the sun rotates around it.
A fast deceleration caused by what?
Like detecting a crack or fault in the tube structure shortly ahead of the current location and it needs to come to an immediate stop.
Most fast-decelerations that planes suffer are imposed at 9.8m/s^2...
Actually almost None do, a plane becomes a glider when it's engines quits and glides to the ground. 9.8 m/s^2 would imply that it descends straight down like a rock with no air resistance. When engines fail planes can glide to a landing and then skid on the ground with the resistance of the ground slowing the plane down during the "slapdown"
http://en.wikipedia.org/wiki/Controlled_Impact_Demonstration
The target speed was never 4000 MPH (I think you're confusing this with ET3's proposal). For deceleration: emergency brakes and the cars have wheels for emergencies. One question that should be asked is, what is it going to crash into? Not other capsules, they're moving away from you and have a huge safety margin of distance between them. Not the station, it's a passive system that handles deceleration (no power required). If the capsule needs to decelerate themselves for some reason, you're going from a maximum of 760 MPH to 0 MPH using the capsule's mechanical emergency breaking system. At the same deceleration as the capsules would accelerate, that's about seventy seconds over roughly seven and a half miles. Which is much faster than a high-speed train can do the same thing.
The document Must posted does cover several emergency scenarios. Passenger health emergency? Best thing is to keep going to next station as scheduled, with a maximum trip length of 35 minutes it's the fastest way to get an active response, and much faster than you can get emergency services to an in-flight aircraft. Major depressurization of a car? Actuate emergency breaks on all cars and rapidly re-pressurize the entire tube. Major earthquake (beyond the ability of the pylon dampers to handle)? Emergency break all the capsules and wait it out. Power outage? The system has many times more stored battery capacity to complete all in-progress journeys. Power failure of system itself? Cars are self-powered, so can coast a decent distance themselves, and then the batteries normally used to power the turbine can be used instead to power motors on the emergency wheels to get the capsules either to the station at the end of the line or the closest emergency exit location. I'm sure there are tons of possibilities that haven't been accounted for, but many are.
We don't need to build all the intervening tubes, do we? Just get it up to speed, then launch it every 5 miles or so; I'm sure we can catch them safely.
Jhyrryl
Amtrak spent $80 million back in the 1980s on a plan to build a high speed rail from LA to San Diego. Every little burg between the two cities sued to stop it. They finally sold the plans to somebody for $5 million.
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If you read the paper in detail, you'll find some numbers. Since it's not a really hard vacuum inside the tube, and since it's cylindrical, the tube isn't as thick as you'd think. The tube walls are 20 to 23 mm thick (0.8 to 0.9 inches). That thickness can handle the load of the pressure differential, the torsion of its own weight between pillars, and the loading caused by the passing of the capsules, as well as standing up to quite a bit of seismic activity. Steel is pretty strong stuff. Cost for just the tube in the passenger-only model is $650 million. Upgrade the width to allow it to transport cars and light trucks and the tube costs somewhat less than twice that. $1.2 billion or so. That includes fabrication.
Surprisingly enough, the pillars cost more than the tube. Steel reinforced concrete with height adjustment gear should run around $2.55 billion for the passenger-only version or $3.15 billion for the vehicle version.
I suspect the competing design is spending more on real estate than the entire Hyperloop system. Hyperloop can use much of the I-5 route, saving a fortune in real estate costs, an option not available for heavy rail on the ground.
Consider first that sufficiently large deflection would result in the immediate emergency breaking of all capsules. There is also the consideration that earthquakes don't travel instantaneously, which means there is some advanced warning between an earthquake being detected and an earthquake reaching the hypertube. There is also the capability of the dampers on the pylons to absorb a certain amount of movement. These things combine to give sufficient time to decelerate the vehicles.
Consider this: earthquakes are a far larger problem in Japan (both in intensity and frequency), and there are similar consequences to deflecting the rail of a high speed train (the danger there is derailment). Even a stationary train can topple in an earthquake, much less of a concern on the hyperloop. Japan has never suffered a fatality on a shinkansen due to earthquakes, over the past half century. The hyperloop's emergency stopping distance would be vaguely similar to that of the shinkansen. The shinkansen emergency braking from top speed takes about 40 seconds by my math, and the *normal* deceleration from top speed of the hyperloop would take 70. If it decelerates faster than normal for emergency braking, it could potentially even stop faster than the shinkansen.
We missed the opportunity to fix this back in the 1960s and 1970s, when the railroads were pretty much all bankrupt. The fix would have been to buy the mainline trackage (everything except the maintenance yards) from the railroads and give them a 20 year free ride to help pay for the deal; then run the railroads as part of the National Highway System. Then the railroads could have become the customers rather than the vendors, and the government, which generally does infrastructure pretty well, could have made the rails a viable solution while the railroad companies, which could then compete on an equal basis, could do the business things, which they do pretty well. And new companies could enter the market to provide passenger train service on an entrpreneurial basis.
Alas, instead we had a huge bailout of railroad companies, and the creation of the bastard stepchild Amtrak, which was designed and intended to fail, but has continued to survive despite the best efforts of the government and the railroads to kill it.
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"this will be cheaper than a high-speed rail?"
Red tape? ROW restrictions? Sound Pollution? Grade restrictions? base material restrictions? etc. High speed rail has some pretty significant drawbacks that limit its use and increase its costs. There are some pretty significant advantages to elevating the "tubeway", decreasing the size of the footprint (ROW in this case) and simplifying the "cars". Not saying its going to be a walk in the park, but with high speed rails mounting costs ($65-117 Billion and climbing) for Californians HSR project alone and ever distant completion times (2040 at the earliest) alternatives should be considered.
Obviously you didn't RTFA as a ordinary idiot. Part of the proposal is to turn that boundary layer problem into an advantage by turning it into an air bearing and having a turbo fan engine (electrically powered... another of Elon Musk's ideas he has toyed with so far as to make electrically powered airplanes) suck up the air in front of the pod and blast it out of the back of the pod.
The air itself in the tube isn't really moving. The tube is kept at a partial vacuum, but it doesn't have to be a perfect vacuum. Essentially, the pod is "flying" through the tube in a fashion similar to an airplane.
At least download the PDF file and make some intelligent comments rather than suggesting the guy is insane based upon wild ass speculation of what folks thought the concept might be prior to Musk's announcement.
Feasibility: No new technology needs to be developed. It uses no exotic technology or materials. Think about the components: steel tubing, concrete pylons, solar cells, batteries, compressors, conventional electromagnets (no superconducting or rare earth magnets). It is an engineering and system integration problem. It is no where near as hard as what SpaceX and Tesla have already done. Tesla can supply the expertise for batteries and linear motor design based on their current experience.
Economy: The claimed price is $6 billion US. The price could be off by a factor of 3 and it would still cost half as much as the existing rail proposal. More then enough room for cost overruns. Musk experienced this already on SpaceX and it did not kill the company.
Benefits: It leapfrogs all existing high speed rail technology. It's a complete game changer. A successful outcome would immediately generate a world wide demand. There is a staggering amount of money to be made. In addition, it is ecologically very sound. The worst aspect is likely the amount of energy required for the concrete pylons, and that seems less then an equivilant roadway. Plus solar power is getting cheaper, so some of the price will go down in the long run.
If the US had any real capitalists around, they would jump at this opportunity. I expect without Musk it will go nowhere, because most big capital expects automatic government guaranteed profit. Although there have been some modest examples of innovative capitalism in the last couple of decades, for the most part capitalism in the US is non-existent, except for a few lone individuals.
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Building a hyperloop from San Francisco to Sacramento, or San Francisco to San Jose, would be useful and much shorter and cheaper.
The pipeline industry has been solving it for decades. There's even an oil pipeline over a fault in Alaska that moved by ten metres in an earthquake which survived because of a clever design of a couple of bends over the fault. For extreme thermal expansion problems look at power station pipework, and something like this is not so limited to materials that can withstand high temperatures and pressures. Great big compressible plastic rings are used between segments of some water pipelines for instance.