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Electromagnetic Ship Docking System Debuts

Makarand writes "A system that uses electromagnets for docking ships is getting ready to be tested at a port in the Netherlands according to this article in the New Scientist. Magnetic docking systems were never used in the past as magnetic fields posed dangers to sensitive cargo like TVs and monitors. Researchers at the Delft University of Technology have developed electromagnets whose magnetic fields do not penetrate far into the ship for this special application. The magnets can be periodically switched off and on rapidly to allow ships to rise and fall with the tide."

20 of 164 comments (clear)

  1. hm.... by bafu · · Score: 2, Interesting

    I wonder if the points where they plan to mount all of the electromagnets are going to up to the job... it doesn't seem like they would have been designed for stress in that direction.

    1. Re:hm.... by MBCook · · Score: 2, Interesting

      I'd imagine that as long as you attached to where there is a bulkhead on the other side of the hull, you'd be fine. They may not have been designed for force in that direction, but I doubt that there would really be enough force to worry about.

      --
      Comment forecast: Bits of genius surrounded by a sea of mediocrity.
  2. If this works... by girl_geek_antinomy · · Score: 2, Interesting

    If they can make this work, then it sounds great - I'd be concerned about the risk to the ship's own electronics, though, as much as to its' cargo. Computerised navigation systems, and the like, and ship-wide systems whose wiring well run very near, or even along the inside of the hull... Neat idea, and one that may well send the internationnal rope-manufacturing industry into decline - after all, who else needs four inch diameter hemp ropes in this day and age...?

    1. Re:If this works... by brokenwndw · · Score: 2, Interesting

      In free space, at least, and reasonably far from the source, static magnetic (and electric) fields always decay as 1/r^n for some n. People write the field at a distance r from a magnet in what's called a "multipole expansion":

      B = [messy coefficient] (1/r^3) + [messier coefficient] (1/r^4) + ...

      Unless the coefficient of the first term is zero, then, very far from the source the rest of the terms become negligible and the field drops off as the inverse cube (becoming a "magnetic dipole field"). (For electric fields the leading term is 1/r^2, not 1/r^3. This is because there are electric monopoles but not magnetic monopoles.)

      The trick, then, and what these guys have presumably done, is to make the field really huge close to the magnet (using all those terms in the ... there) but to zero out or minimize the components that reach far away (i.e. the 1/r^3, then the 1/r^4 if you can, etc.)

      (Disclaimer: yeah, yeah, this doesn't take into account matter in the way, and the magnetic field is a vector. But that doesn't change the basic idea.)

  3. where is this being used/could this be used? by no+reason+to+be+here · · Score: 3, Interesting

    I can imagine this tech being great for mid-air and outer space docking situations? is this kind of technology in place for such applications already?

  4. 1.5 Tesla Cryomagnets by VoidEngineer · · Score: 3, Interesting

    So, at work, I work with a 1.5 Tesla magnet (Gyroscan Intera... used for nuclear magnetic resonance imaging; VMS/VAX/Solaris Operating Systems). Price tag on the thing is about $1M, which makes me wonder:

    1) Did this docking system actually cost only $50M? At $5M a year, is a 10 year return on investment reasonable?

    2) Is it actually Helium/Nitrogen cooled? We have to have a dedicated coolant system for our magnet to work at 1.5 Tesla. Moreover, what happens if a magnet breaks? They're not going to vent 2,000L of Helium, per magnet into the ozone, are they? (52 magnets = 100,000L total of liquid Helium)

  5. Dockworkers Response by limekiller4 · · Score: 2, Interesting

    From the article:
    "Mooring a ship can be a time-consuming, labour-intensive affair in which dock workers grab ropes hurled from the deck of the incoming ship and secure them to the dockside."

    I've never been one decry progress because it'll put some people out of work, but this does have the potential to unemploy a whole crapload of people over the not-so-long term.

    I wonder how the dockworkers union is handling this?

    --
    My .02,
    Limekiller
  6. Power failure? by tstoneman · · Score: 3, Interesting

    What do you do in the case of an extended power failure? I know they probably have diesel backups, but even those only last so long.

    At least living in the Bay Area with all the uproar about the "Energy Crisis" a couple of years ago, this may not be the most reliable system if you had to rely totally on electricity to dock all those boats up there in Oakland....

  7. Re:So what does the dockworkers' union think? by carlhirsch · · Score: 3, Interesting

    I expect the ILWU won't give a good god-damn about how the ship is moored as long as they are the ones who run the equipment, handle the cargo coming off the ships, and they're the ones who handle the clerical work. It was actually clerical and back-office jobs that triggered the recent strike. And no, they weren't opposed to technology, they simply wanted to make sure the minds and hands behind the technology had union cards.

    One reason the ILWU had become such a powerful, well-paid union is the fact that when cargo got container-ized rather than loose-packed, they embraced change and took payouts for the workers displaced by the new equipment.

    --
    . We've got computers, we're tapping phone lines, you know that ain't allowed - Talking Heads, "Life During Wartime"
  8. Danger!! by Anonymous Coward · · Score: 1, Interesting

    lets just hope no one on any of the ships has any percings.

    But it would be interesting to see what happened when they power it up.

    1) The guy(or gal) gets all the piercings torn out of their body.

    2) They just fly off the deck of the ship and hit the electromagnet face first.

  9. Re:So what does the dockworkers' union think? by tpengster · · Score: 1, Interesting

    Seriously, in the U.S. we just recently had a paralytic dockworkers' strike. I don't think they'd be amused by this labor-saving innovation. Not that I think people should be kicked out of jobs by robots.

    Back in the 80's, the Japanese started using robots to build cars. Here in the US the Auto Workers Union, afraid the robots would replace American jobs, wouldn't allow the manufacturers to use them. Now the Japanese technology is far ahead of ours and the Japanese have a competitive advantage.

  10. Not as usefull by mlknowle · · Score: 3, Interesting

    I've spent several years working as a dockhand for large yachts (100-200 feet). While these boats arn't as big as the tankers and cargo ships which will utilize the magnet system, the manuvering and handleing is similar. Dock lines are not just used to hold the ship once it is in position to the dock - they are also used to manuver the vessle as it is docking (for example, a line will be thrown from the front of the ship, made secure, and the ship will power against it to bring the back of the ship into the dock). Obviously, the magnets wouldn't work at this range (50+ feet)

    Methinks docking lines might be a bit cheaper too - and when properly set, only slight adjustments need to be made for the tide.

    What would be very cool to see is the magnet start attracting someone's belt loop or a leatherman out of someone's pocket standing nearby... wow

  11. A solution looking for a problem by NumberGod · · Score: 5, Interesting

    You've never going to save 40 minutes.

    This is just a solution looking for a problem, and I'll predict that it'll never ever be used.

    I live at a port in New Zealand (just outside Christchurch actually) and often watch the ships docking. My father used to tie them up. If I look to my left, I can see about a half-dozen ships out my window.

    The majority of the 40 minutes that the article quotes, that it takes to berth the ship, is the tugs turning, and pushing the ship to the wharf. That's the thing with ships, they have a big propeller at the back, which pushes them forwards, and they can't move from side to side. They do have a rudder, but it's not designed for more than a few degrees of turning, you can't use it to dock. (I'll stay away from bow thrusters for now)

    Basically the process goes like this...

    A Pilot (who works for the port, and is an expert in the local navigation/conditions of the port) is taken to the ship on a small launch, and meets it several miles from the harbour.

    The Pilot then commands the vessel, until it's tied up at the wharf. (s)he co-ordinates the ship, tugs, and wharf staff who, at the end of the operation drop the ropes over the bollards.

    Securing the ship with the ropes takes about 5 minutes on a slow day, getting the ship alongside the wharf takes about 35 minutes. The thing with ropes is, that...

    1) They're proven. They've been using them for thousands of years.
    2) It's a standard system, used all over the world.
    3) It's simple, never underestimate this.
    4) it copes well with varing weather and tides.
    5) You still need ropes to tie between the tugs and the ship.

    Now, as I said before, you've going to save about 5 minutes per berthing? Your damage costs are going to far outweigh the costs of any savings.

    And, what happens when the power goes out?

    The ship floats away, probably onto rocks.
    Backup Generators? Yeah sure, a diesel generator is going to hold a ship with 4-8000 shipping containers alongside a wharf, is bad weather, and an especially high tide, with no outages.

    I'm sorry, but there's no way this would ever work.

  12. New for big ships, but not for small by stefanb · · Score: 2, Interesting
    This probably is new for sea-going ships, but for ferry-like ships and boats, where the stay will be only a few minutes, magnetic systems have been in use for quite some time.

    Although I can't find any technical details from Google, the Alsterdampfer in Hamburg, Germany, have been using a magnetic system for at least 30 years (no snide comments about my age, please). In this image, you can see the magnets as the black-faced buckles on the side, just above the waterline.

    For this to work, the side of the jetty is plated with steel plates for the magnets to hold on to; depending on the skill (or inclination ;-) of the captain, the boat can be tucked towards the jetty quite violently...

    1. Re:New for big ships, but not for small by Deadstick · · Score: 2, Interesting

      I'm pretty impressed by the system they have on the passenger boats on the Rhine. They have no screws, as such. There's a single vertical drive shaft that sticks down through the hull amidships, and rotates a horizontal wheel. Blades much like those on an aircraft propeller extend vertically down from three points on the wheel, so they rotate somewhat like an eggbeater. A system of levers and bellcranks varies the pitch on the blades as they go around, and by setting the levers you can apply a torque in either direction and/or a translational force in any direction, independently. You can run forward like an ordinary boat, spin in one place, or move sideways into a dock at will.

      Those boats make passenger stops every two or three miles, and it doesn't take up much more time than a bus stop.

      rj

  13. Re:So what does the dockworkers' union think? by ryanvm · · Score: 2, Interesting

    Not that I think people should be kicked out of jobs by robots.

    Why not? Automation is a good thing. Do you think that we should still be using switchboard operators and elevator attendants? As the level of automation in the world increases, the total amount of manual labor that mankind must perform decreases. Ideally, we should get to the point where the only work we're doing is maintaining/improving the robots.

    Besides, if these magnetic docking systems put a few longshoremen out of work, so what? Is it really such a terrible thing that they better themselves and learn a new trade?

  14. Re:Residual magenitsm of the hull? by cybermace5 · · Score: 4, Interesting

    Ships routinely have degaussing coils run along the inside of the hull.

    The earth's magnetic field tends to magnetize a ship over time. During the second world war, torpedoes and mines used magnetism as one method of detecting that a ship was near. The magnetism would also mess with the compasses, of course. Large ships, lacking degaussing coils, would routinely go back to port and dock in a way that used the earth's magnetic field to gradually cancel out the ship's magnetism.

    --
    ...
  15. I'm annoyed by a lot of these comments by Fastolfe · · Score: 4, Interesting
    A lot of these uneducated comments in here are really bugging me. I see a lot of people saying this is a stupid idea, it'll be too expensive, it'll never work, etc. What is with all of the negativity?

    First of all, this is an experiment. Experiments never usually make money in the short term.

    Secondly, here's a quote from the article (which several posters need to actually read):
    If it works, they say the system could save them around 5 million Euro a year in labour costs, and speed ships' average turnaround times by 40 minutes.
    Could we please concede the possibility that someone has done a marginal amount of research into this and backed these figures up on some real numbers? Maybe it won't save them that much, or maybe the whole thing will end up costing too much. That's the point of an experiment, after all: to determine if something is going to work.

    And for all of the couch port authorities inhabiting Slashdot, please remember that this is probably going to be done with the blessing (and financial support) of a large ocean port. I know that perhaps many of you think you know more about docking ships, managing large ocean-going vessels and the expenses associated with these activities than those in charge of these ports, but please take a deep breath, relax for a minute, and consider the possibility that maybe they're supporting this experiment for a reason, and that reason probably has less to do with a mad scientist trying to dupe someone into buying them a lot of expensive magnets and more to do with a convincing argument that this experiment could save them money in the long run.

  16. Re:Risk to video and audio tapes, hard drives... by Walt+Dismal · · Score: 2, Interesting

    Yup, I did read it, but one of my unvoiced concerns is that a 1 Tesla field is only the final steady state value. When you pulse current into an inductor or turn off current, in any real-world system it is not a pure inductance, and often ringing occurs. When that happens, the instantaneous values of the (presumably damped though ringing) current could hit higher peaks. I don't know what pulse levels may occur, what EMI induced effects may occur, etc. The external docking electromagnets could induce currents in the hull that couple inward.

  17. Re:So what does the dockworkers' union think? by Saeger · · Score: 2, Interesting
    Ideally, we should get to the point where the only work we're doing is maintaining/improving the robots.

    That's a pretty weak ideal future; humans slaving away oiling up their robot master so it can build Nike's 7% faster. :)

    Ideally, we'll get to the point where advancing robotics, nanotechnology, and IA & AI, will result in the technological unemployment of just about everybody on and off Earth. And just when society is getting used to the idea of an economy of unimaginable abundance, the next shockwave will hit.

    --

    --
    Power to the Peaceful