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Pipeline Mass Transit?
pipingguy writes "'Evacuated Tube Transport (ETT) is a new kind of transportation system that requires less than two percent of the energy of current transportation methods. It is also much safer, and can be faster. [...] Anyone can visualize 2 tubes (one for each direction) along a travel route. Air is permanently removed from the tubes; so travel takes place without friction. Pressurized passenger capsules (like a 2 - 8 person airplane cabin), travel in the tubes on thin steel wheels or on nearly frictionless Maglev. Airlocks allow access without admitting air to the tubes. Linear motors (as used on new rollercoasters) accelerate the capsules. During most of the trip the capsules coast; using no power. When the capsules slow down, linear generators recover most of the electrical energy used to accelerate the capsules.' Some CG images and drawings here, the FAQ is here." MSNBC had an article on monorails a few days ago. Don't bother making Simpsons jokes, the article has them covered already.
Why, you ask? Not because it's not interesting and efective technology, but because we Americans don't like mass transit. We want cars. We have a *right* to cars. Look in the Bill of Rights. It's there. Or if it's not, I think it should be, so it might as well be there right next to my right to own a minigun.
Seriously, though, there are hundreds neat ideas for viable mass-transit available, but I'm stuck riding a 30 year-old, beaurocracy-lader system called BART to work everyday. That has, to put it mildly, soured my viewpoint somewhat. Until we remove the corruption that wil always accompany mass transit, we might as well forget about it.
Every year during my review, I just pray the words "slashdot.org" aren't mentioned.
Now that articles are making pre-emptive Simpsons jokes, if they would just include "OMG FP FP FP!!" and "Imagine a Beowulf cluster of...", we could eliminate half the comments on Slashdot.
Fry: Whoa!! [He sees the tube transport system and gives it a try.]
Man: Radio City Mutant Hall! [The man is sucked up into the tube]
Fry: Um. Cross Town Express? [He is sucked up into the tube] Whaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa! [People look up from the street and stare at him. He is taken across the city, past the Statue of Liberty, underwater and finally out the other end smack into a building.]
Man: Pfft! Tourist!
Mordor...a magical, mythical land where women are more rare than dragons--but where every man would rather find a dragon
Yeah, just like the old pneumatic underground made by Alfred Ely Beach, except it's not pneumatic. And it uses two single directional tubes, recycles energy, travels at 300mph, is powered by an electric motor, and runs in a vacuum. But, other than that it's exactly the same.
You'll never keep a vaccum with this.
Not with the hundreds of miles of tube.
Not with termal expansion/contraction.
Not in an active city with people building, digging holes, running infrastructure.
Not in an even remotely seismic active area (remember the earthquake in NY?).
While its a cool idea, its just that, an idea. There's no way to overcome the problems and still make it as durable and cost less than existing technology.
I'm out of my mind right now, but feel free to leave a message.....
Except without the falling and the crashing and the screaming.
Every year during my review, I just pray the words "slashdot.org" aren't mentioned.
They must maintain a vacuum however the length of one tube is from city to city, so even one hole along the path destroys the vacuum. I imagine maintenance costs to prevent this and security costs to prevent malicious people putting holes in it would be high.
Another thing is suppose one of the cars gets stuck. These things are going 300-4000mph in an environment that's supposed to be virtually frictionless. How do you stop all the other "cars" behind the broken one in time?
How gradual do the turns have to be? You can't exactly make a quick right turn at 300+mph and still have a comfortable ride. Maybe there will be no turns and it will stop every time it needs to change direction.
And doesn't this kinda remind people of network switches? Computerized management of "people packets" zooming through tubes?
If we were discussing ideal friction, you'd be right. However, there's one big problem with that: The real world isn't ideal, and race cars have bigger contact patches than minivans for one very good reason: more friction.
Finally, friction isn't the only source of energy loss in a rolling tire. In fact, as long as you aren't skidding, almost none of the energy is lost to friction (because rolling friction is really a special case of static friction and energy is lost in dynamic friction). Most of the energy in rolling a tire is lost continuously flexing (and heating) the tire sidewall under the weight of the vehicle.
Thin steel wheels deform a whole lot less than radials and will therefore lose less energy when rolling.
But Heinlein had the right idea. Dig the tunnels deeper and have them follow great circles through the crust. Then launch the cabs to orbital velocity (but inside the earth). No wheels. Or expensive magnets. Just a nice vacuum and a very fast ride. Of course, the acceleration/deceleration might be a bit brutal...
Regards,
Ross
Less than it is to keep a plane in the air?
No. Say you have a train tube that's a reasonable length-- LA to San Francisco, Dallas to Houston, New York to Washington. You have to maintain a high-quality vacuum over that entire length. It's really late, so I'm not going to do the math for fear of getting it wrong and ruining my point, but the volume of such a tube would be really, really large. The surface area would also be really, really large. The likelihood that you could maintain a vacuum in such a tube is essentially zero. This is particularly true in an environment like the central California valley, where two points of land on either side of a fault line can shift as much as a foot in either direction over the course of a year or so, and that's without an earthquake.
More dangerous than flying?
Definitely. If a plane crashes, it's obviously horrible for the passengers, but the danger to bystanders is minimal. A plane crash-- one caused by failure or error, not deliberate malice-- might kill a few people on the ground, and that would be terrible. But a catastrophic failure of an evacuated tube would have the force of a medium-sized bomb, and it would be spread out all through the city, the countryside, et cetera. Thousands could be killed in a catastrophic evacuated tube failure, unless the tubes were all buried deep underground. As has already been discussed elsewhere, that idea has survivability problems of its own.
And cars are still much more dangerous.
That's a common misconception caused by the careless application of statistics. The total number of automobile fatalities per year is umpty-thousand. That sounds like a big number, even when you compare it to the total population. But when you look at the numbers another way, calculating an individual person's likelihood of being involved in a fatal automobile accident in his or her lifetime, the percentages come out very close to zero. That's why automobile liability insurance is still available, and affordable. Automotive transport is actually quite safe from an actuarial point of view.
I write in my journal
Notice how "mass entertainment" in movie theaters is facing a challenge from the home theater trend. People are increasingly choosing to watch movies at home on their DVD players and big-screen TVs with surround sound systems. It puts the individual in control of geographic location of viewing, start time, end time, pausing, instant replays, volume, language, viewing angle, viewing chair/sofa/bed/carpet, lighting, smoking/non-smoking, drinking if you please, any food allowed, and countless other variables that affect the entertainment experience.
This patent is another ridiculous one. It's nothing new at all.
I can't find any reference to it online, but in the early 80s or late 70s NASA came out with a design for a trans-continental train... in a vacuum tube.
The train was to have (guess what?) two tubes, and would be driven by maglev (360 degree maglev -- on all sides of the train, keeping it centered in the tube). There was much discussion of what happened if the power went out, how it would come to a soft landing, etc.
The other idea in the design was that to save energy, most of the power used to accelerate one train would come from the power generated in decelerating the other.
The design document included the projected costs of construction ($100 billion or so, if memory serves me correctly), the speed (5000 MPH), and the projected ticket cost ($40 NYC to LA).
The train cars were designed with chairs which rotated, because half the trip would be acceleration, and half deceleration, so you'd face forwards for the first half and backwards for the second.
The trip was projected to take about 45 minutes.
I wish I could find it online, but I was very impressed with the design at the time, and remember most of the details.
Hey, has anyone read NASA's "Space Communities: A Design Study" from 1976? That's another not-well-remembered document. We're barely at stage 2 (out of 6 or so in the book) so far. The L5 space station NASA's just proposing is in there... these guys think long term (or some of 'em anyway).
OK, you're all skeptical. Here's the FAQ from my investment prospectus.
They have no intention of building anything, just make money for their shareholders from tha patents. And this encourages innovation? All it does is put a roadblock against someone who really wants to build it.
From their site ("company summary" page)
Our aim is to generate returns for our shareholders by acting now to acquire control of important blocks of intellectual property (patents and trade secrets) in the ETT field. We currently own the patent and trade secret rights to Evacuated Tube Transport, the first practical evacuated tube transport technology. We believe that these ultra efficient and environmentally benign systems, will become key components of numerous future worldwide transport systems. ET3.COM INC. intends to take full advantage of the generic nature of this unique technology by securing the intellectual property rights on the lion's share of all specific applications, new devices, and novel systems issuing from it. Management also believes that we are well positioned to gain control of other major intellectual property by developing new patents and trade secrets through our own internal efforts and by developing patent-exploitation agreements for the patents and trade secrets belonging to others.