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Japan Transportation Technology

Japanese Researchers Test Flying Trains 221

An anonymous reader writes "As an alternative to maglev trains, Japanese researchers are working on ground-effect vehicles. A ground-effect vehicle takes advantage of fast-moving air and uses some stubby little wings to fly just above the ground, like a maglev without the mag. This is a tricky thing to do, since you have to control the vehicle more like an airplane than a train: you have to deal with pitch, roll, and yaw and not just the throttle. A Japanese research group has built a robotic prototype of a free flying ground-effect vehicle that they're using to test an autonomous three axis stabilization system."
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Japanese Researchers Test Flying Trains

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  • I, uh, hmm. Okay. In Bizarro World, do they also have Submarine Cars and Space Boats?
  • by parallel_prankster ( 1455313 ) on Wednesday May 11, 2011 @01:15AM (#36090754)
    This one needs a wing span space, not as thin as current trains. But if this design saves a lot of energy, why the heck not. This is really like a low flying airplane which sounds like a cool idea.
    • I can't see how it could save energy. At it's simplest, maglev requires two permanent magnets to provide the "lift" (or technically, the repulsion) and then some motor to provide the forward motion. This requires a motor to provide the forward motion and the lift.

      Or put another way, maglev must overcome the friction of the body. This must overcome the friction of the body and the wings.

      The only possible energy savings that I see is that the current generation of maglevs use superconducting magnets which req

      • Yes, a ground-effect train would require more energy to propel at a certain speed than a mag-lev train of similar mass and size, but there are other areas where both energy and cost savings are made.
        It would require a lot of energy and cost a lot both to produce the materials needed and during the construction of a mag-lev rail network. A ground-effect "rail" is basically a concrete culvert. Takes much less energy, resources and money to build and maintain.
        Then we have the energy needed to, as you mentioned

        • The biggest problems that I can see with ground-effect trains is that they'll have to bring the energy needed, just like a air plane.

          No it won't. It's only floating on a cushion of air a few centimeters above a track, just run 2 electric rails in the track and drop a pickup arm to make contact with the rails.

          Something the weight of a train, I can't see it bobbing up and down very quickly, I doubt it would even need to be an actively positioned arm, just something with a pivot and a spring pushing the arm

      • by cptdondo ( 59460 )

        I don't know about saving energy, but the tracks would be cheaper to build. Maglev tracks require magnets in every inch of rail; that's a lot of technologically complex stuff. This looks like it needs a concrete trough; something we can build with an extrusion machine if needed. (Look them up; they make extrusion machines for bridges; why not this?)

        Lots cheaper and simpler. It will require lots of room and it will be ugly, and there are other issues - trash, water, etc - but that could all be handled som

    • by AmiMoJo ( 196126 ) on Wednesday May 11, 2011 @05:35AM (#36091764) Homepage Journal

      They will run into problems with noise. In Japan noise concerns have limited train speeds since the first days of high speed rail in the early 60s, particularly around tunnels where there is a boom every time a train exits. One advantage of maglev is that due to there being no contact with the ground noise is reduced significantly, but adding prop or jet engines would seem to make this train louder than a normal electric one.

      France runs 500kph trains and the only reason Japan doesn't is noise. The latest generation bullet trains that do 300kph have a very unusual shaped nose designed to reduce noise.

      • by xaxa ( 988988 )

        France runs 500kph trains and the only reason Japan doesn't is noise.

        France runs trains at up to 320km/h, the speeds higher than that were only for a demonstration/recordbreaking attempt, where the noise doesn't matter.

        Living near a moderate-speed line (200km/h conventional trains go past) almost all of the noise seems to be wind, not wheels, but ICVWBW.

        • ICVWBW == I could very well be wrong. ?

        • by delt0r ( 999393 )
          Almost all the drag is air friction on these trains. About half of that air friction is from the wheel bogies. So loosing them will save you a bit. I follows that the things that contribute most to the air friction also contribute most to the noise, so you get a saving there.

          However friends that have gone on the maglev in china said its is *not* quiet.

          Also you can reduce friction by going slower. Going 70% the original speed will halve the air friction. Again it follows that this is also quieter.
      • ...particularly around tunnels where there is a boom every time a train exits.

        I wonder if you could solve that by changing the shape of the tunnel exits, like maybe with a gradual funnel shape instead of a hard cut-off?

        • by AmiMoJo ( 196126 )

          They have put baffles on some of the tunnels in an attempt to do that, or used sound barriers at the side of the track.

  • Ok (Score:3, Interesting)

    by ShooterNeo ( 555040 ) on Wednesday May 11, 2011 @01:21AM (#36090790)

    So if you look at the article, doing it this way does NOT eliminate the track. There's still a complex track that the train runs in - that U shaped concrete trough that you can look at in TFA. The walls of the trough prevent gusts of wind from shoving the train around. The control system would have to be extremely precise, and able to react very quickly to events like a big gust of wind. I would guess the 'train' car has wheels.

    Advantages - the track doesn't have coils or magnets in it. But one glance reveals that it's still an extremely expensive, complex effort to build the track - probably millions of dollars per mile.

    Disadvantages : in every respect, it's still a high speed train. The ground effect trick is to achieve faster speeds without magnets, that's all. If you board one of these, you have to be going to a specific destination all the other riders are going to. Every stop slows it all down. Most of the time you save on one of these you lose due to waiting to board the train, walking to the train, etc. And you're crowded in with the public.

    And while you eliminate the need for coils in the track, you have to use even MORE concrete and steel to make the cage visible in TFA, and you now need an extremely high performance control system in the train that needs to work for the train to not crash.

    In short, it's a terrible idea. What we need are cheap robotically controlled cars that run on a switching network that go from starting point directly to individual destination. These cars don't even need to be all that fast, and could use conventional technology (except perhaps using capacitor banks and frequent charging points or something...but conventional tires, road, etc...we'd use the road network we already have and install fencing and barricades and bridges so no pedestrians can ever enter the streets)

    • First off, concrete is cheaper than magnets. You'd need the control system anyways to run a maglev train. And when you're talking about a trunk line that's already moving hundreds of thousands if not millions of people on a regular basis, it doesn't matter that everybody is going the same route. No, you've got it half right: combine the two. Have a high-speed trunk line and then the cheap switching cars branch off from major stations.

    • Re:Ok (Score:5, Insightful)

      by PIC16F628 ( 1815754 ) on Wednesday May 11, 2011 @01:43AM (#36090898)
      Conventional (wheel on rail) Trains have far more advantages than a individual car for most journeys:

      1. Very low energy consumption because of metal to metal rolling friction. Car tyres bend to become a plane of rubber in contact with sticky tar causing very high friction. Yes, the packet switching analogy is nice and best for computers but not for people. Because people will use the car more and more. See the bad points below.

      2. A thousand cars driven by thousand individuals has a far bigger probability of accident simply because 1000 minds are involved without any central oversight. Who knows what these minds are doing on the road. A train is centrally controlled with professional crew.

      3. When you have a car and the road is free and there is parking space, you will use it to go the next street to buy milk. In effect we will use a hammer all the time for all the jobs because the hammer is easy to hold and use. The moment public transport has to be used, you will make a trade-off analysis and use it only when required. Saves the planet, saves your limbs from degeneration.

      4. Trains uses far lesser space. Compare a 8 lane highway with a two-lane railway track. Not only do cars need lot of space while moving, they lot of space at both origin and destination. Since destination can be anywhere, you need lot of space everywhere. What a sheer waste of resources.

      5. You can be a zombie in a car or enjoy relaxing and eating and sleeping and reading and listening in a train.

      • But that's just it. You can't go down the street to Walmart for some groceries without a car. Even if there were buses, they are full of just anyone - including scary people that the American public has been conditioned to fear. (yes, I know rationally that that scraggy guy who smells funny is probably not an axe murderer or rapist...but does a woman bringing her 2 kids know that? This is why no one rides the buses unless they can't afford anything else)

        And we've spent uncountable amounts of money creat

        • Re:Ok (Score:5, Insightful)

          by ryanov ( 193048 ) on Wednesday May 11, 2011 @02:31AM (#36091046)

          First of all, no one should shop at Walmart period. It is a soulless evil company at all respects that hurts all of us on a daily basis. Second of all, thanks to their tax cheating ways, no one lives down the street from a Walmart anyway. There are plenty of grocery stores in reasonably built areas that are walking distance. Many of them even deliver.

          Second of all, you absolutely can buy groceries on foot -- ever heard of a cart?

          Third, sunk money? All of the road maintenance and fuel and costs to the environment are on-going. Slowly moving to a model that makes economic and efficient use of space will save money in the long run.

          Really, all of your problems have been solved already: people not living in places that are less dense than streetcar suburbs. Raise the price of gas over time, people will move, and we don't have to deal with all off this robot cockery.

          • Really, all of your problems have been solved already: people not living in places that are less dense than streetcar suburbs. Raise the price of gas over time, people will move, and we don't have to deal with all off this robot cockery.

            Thank you for making the decision for me and my family on where we will live. It's such a relief knowing that people like you, who are so much more smarter than little old me, are out there protecting me from myself.

          • Third, sunk money? All of the road maintenance and fuel and costs to the environment are on-going. Slowly moving to a model that makes economic and efficient use of space will save money in the long run.

            Or wait till the next natural disaster happens, when you'd have to rebuild anyway.

          • by stdarg ( 456557 )

            First of all, no one should shop at Walmart period. It is a soulless evil company at all respects that hurts all of us on a daily basis.

            Yes, Walmart is so much more evil than all the small stores that 1) don't provide health insurance, 2) hire illegal immigrants at below minimum wage 3) charge higher prices and carry less selection.

            Second of all, thanks to their tax cheating ways, no one lives down the street from a Walmart anyway.

            The Walmart nearest to me (within biking distance) is, oh, 2 blocks away from a large neighborhood.

            There are plenty of grocery stores in reasonably built areas that are walking distance.

            Most of the grocery stores in this country are large national chains. How exactly are they different than Walmart, either economically or "morally"?

        • So basically what you are saying that since it's a bad idea for the US to implement this, it's a bad idea for everyone? You know, different countries and cultures have different needs and priorities :)

          Maybe it really is a bad and impractical idea for the US to implement a system like this, even if the US as a society really should look into ways to reduce their dependency on conventional cars - if nothing else than for the fact that the rising gas prices means the average american uses more and more of his

          • by radtea ( 464814 )

            So basically what you are saying that since it's a bad idea for the US to implement this, it's a bad idea for everyone?

            I think he's saying that his part of American society is based on paranoia and class warfare, and they like it that way.

            Furthermore, most of American society is fundamentally evangelical: they believe everyone should be like them. Their paranoia extends not only to the "other" in their midst, but to anyone anywhere in the world who is the least bit different from them.

            Not all Americans are like this, mind. I took the city bus in LA on occasion when I lived there (the only white person in the city who did

        • by Rakishi ( 759894 )

          But that's just it. You can't go down the street to Walmart for some groceries without a car.

          Why not?

          This is why no one rides the buses unless they can't afford anything else

          No one rides the bus because is 90% of America the bus doesn't go where you want it to go, when you want it or in reasonable time. In places like NYC where it does most everyone is perfectly fine taking public transportation.

          But if we surrounded every roadway used by the robot taxi network with fences (including a barrier on top),

          And where would you place these magical roadways? In what empty space? Which roads would you block to existing traffic? How would you get with cross traffic?And are you aware of how bloody expensive this would be? And how ugly? NIMBY wouldn't let that get within 500 miles of the

      • Re: (Score:3, Interesting)

        by opinionbot ( 1940160 )

        Wholeheartedly agree that for trains and walking / cycling would be an excellent alternative. I own a car, but haven't driven it for over 6 months as I simply haven't needed to: walk to work (20 mins each way), walk or cycle to the shops and take the train for longer journeys.

        Whilst driving can be enjoyable, there is nothing fun about motorway (freeway) driving. For long distances I'd much rather be in a train where I can walk around, stretch my legs, have a table to do some work on, even use Wifi on man

        • haven't driven it for over 6 months

          Your car battery is probably dead by now. Better check it just in case you do decide to drive, and find you can't.

          • Your car battery is certainly dead by now

            FTFY. He'll be lucky if the battery isn't completely useless by now, maybe if he's driving something really old and simple like a Willys Jeep that doesn't have a million little gizmos draining the battery. If it's a car designed from the '90s onward, he might as well pick up a new one right now.

      • by khallow ( 566160 )

        When you have a car and the road is free and there is parking space, you will use it to go the next street to buy milk. In effect we will use a hammer all the time for all the jobs because the hammer is easy to hold and use. The moment public transport has to be used, you will make a trade-off analysis and use it only when required. Saves the planet, saves your limbs from degeneration.

        So we shouldn't use a vastly flexible tool for other uses because you think of it like a hammer? That's really short sighted. Automobile don't have a fixed use. Nor should they. And trains or other public transportation don't help you with those short shopping trips so this argument is pretty much irrelevant. I notice you also ignore that cars are flexible point-to-point travel. Sure, they use extra space than trains or buses do, but you get so much more out of it.

      • by LWATCDR ( 28044 )

        No you are wrong. And you are right.
        Japan has good mass transit. They also have car companies. It is not a one size fits all. I would like good mass transit to go to work but I will still want my car to go shopping.

        1. Yes you are right but tracks do not go everywhere and are not practical in low density areas.
        2. He wanted automated cars. The idea does have some merit. I think a good step would be smart roads. To give an example from experience. Last night it took my wife and I 30 minutes to go a mile becaus

    • The control system would have to be extremely precise, and able to react very quickly to events like a big gust of wind.

      Or, you know, an earthquake.

      Has everyone else got the memory of a goldfish?

  • But wouldn't the money be better invested if they designed trains that can swim instead of trains that can fly?
  • by toygeek ( 473120 ) on Wednesday May 11, 2011 @01:50AM (#36090926) Journal

    Its not too often you see researchers combine technologies and come up with less than the sum of their equal parts. Imagine, a transport that can crash AND derail. Woo!

  • Energy supply? (Score:4, Interesting)

    by MacroRodent ( 1478749 ) on Wednesday May 11, 2011 @01:54AM (#36090940)
    This might be a good idea, if they can figure out how to supply electricity to power the flying train. Tricky, because there is no ground contact, unlike a regular train, and the track itself does not propel it forward, like a maglev track does. Otherwise it has to carry its fuel, which might negate the advantages of the idea.
  • tried floating trains, but that didn't work so well...

  • by damburger ( 981828 ) on Wednesday May 11, 2011 @02:05AM (#36090966)
    This is clearly a derivative of an old Soviet vehicle. They never got much use of of them because they require a perfectly flat surface in order to work properly, hence the Japanese building a specially made track for it.
  • In the graphic showing the concept for the final vehicle, the train appears to use jet engines. Is this really how you would do it? I thought that jets were pretty much dreadfully inefficient unless operated at altitude.

    • Re: (Score:2, Informative)

      by Anonymous Coward

      No. They are ducted fans [wikipedia.org] driven by electric motors. The tips of the vertical stabilisers have small pantographs that contact the underside of the lip at the top of the track walls. It's mostly in Japanese, but you can get the idea from some of the pictures here [tohoku.ac.jp] (e.g. this image [tohoku.ac.jp])

  • it will come to the recognition that a sort of pneumatic tube system will solve all their problems.

    .

    Then it will really mean it, when someone says: I'll ride the tube ;-) ( greetings to London )

    • by zevans ( 101778 )

      England had vacuum railways in the 1840s. (Croydon and South Devon from memory.) One of IKB's madcap schemes.

  • by scdeimos ( 632778 ) on Wednesday May 11, 2011 @02:55AM (#36091128)
    Russians have been playing with huge ground-effect transports, Ekranoplans, since what - the 1960's? There's plenty of WIG (Wing In Ground effect) boats around. Hardly new stuff that needs a lot of research.
    • by Splab ( 574204 )

      The research isn't into how to use the ground effect, the research is into how to stabilize the object autonomously.

  • Pneumatic tube post will be the solution.

    The power to build the air cushion beneath and on the sides can be produced converted within the craft in contrast to the old pneumatic tube model.

    The air for the cushion will be sucked in on the front, reducing the drag.

    The technology of electric pickups for high speed trains is there.

    I think the construction cost for a length of big tube is less than for a Maglev track!

  • Pneumatic tube post will be the solution.

    The power to build the air cushion beneath and on the sides can be produced converted within the craft in contrast to the old pneumatic tube model.

    The air for the cushion will be sucked in on the front, reducing the drag.

    The technology of electric pickups for high speed trains is there.

    I think the construction cost for a length of big tube is less than for a Maglev track!

  • Honest question: What benefits would this have over mag-lev?
    • Honest question #2: What benefits would this have over a regular train? 'Cause I'm not seeing any, at the moment. It looks tough to board, and takes a whole lot of space just for a wingspan.

  • It looks like a geek toy to me. At least as train, such a vehicle would not be very practical. The main problems of todays train systems is not speed, but how many people can be moved and how can cargo be distributed more efficiently. The first thing involves two deck trains, trains without locomotive (which follow more or less the concept of a tram). The second thing has to do with shorter or easier to decompose cargo trains. So they can transfer containers from the harbors to the interior.

    But cool device

  • Am I the only person who read this and remembered the old Heinlein juvie "Starman Jones"? I loved that book.

  • It's not a trainrobbery, it's a scientific experiment.

  • It's more like a grounded-airplane, or plane-on-a-rail.

    mag-lev is mag-lev not only because it use mag to keep things on rail, but it's the propulsion source. Now that "train" thing is going to use turbo fan engine as the propulsion source, not wheel nor mag. So...hey it's really an airplane

  • Once you have the train sitting in a trough, why not use an air cushion to push up rather than a wing pull up? The air cushion exists in the trough where there is no wind. The train could provide the cushion on its own power or the track could carry compressed air in a pipe and deliver it under the train through a network of valves. You would need a low friction moving seal along the length of train but it doesn't need to be great. Make the seal interface float on magnets if you want. It would carry a

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