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B Is this possible? Magnetic tires

  1. Mar 10, 2017 #1


    I hope I am posting this in the right place but forgive me if I am not.

    I randomly came across this video and was wondering if this is even possible. I have limited knowledge on this but I have a few thoughts as to why this would not work. First, would you not have to have a power supply in the tires as well to power an electromagnet strong enough to pick up the car? You would also use a ton of energy from the cars battery to power the magnets in the car. Even if you manage to power the magnets in the tires, how would you keep the pools aligned with the tire spinning? A gyroscope? I could be wrong about this next part but based on my limited knowledge of how an electric motor works, how would you transfer power to the wheels to make the tire rotate? An electric motor requires a coil all the way around the center shaft right? Well the entire bottom half of the tire has nothing around it so how would it make it rotate? The only axis that has something all the way around it is horizontaly making the tire spill in place like a spin top which would not move the car anywhere.

    People in the comments of the video keep siting a maglev train as to how it would work but from my understanding, this is not how a maglev works at all. A maglev has magnets on the track and train to levitate and more magnets in the track in front and behind the train that push and pull to make it move. It doesn't rotate anything and because it would require magnets to be installed in every road, that solution would never work.

    Are my thoughts correct here?
     
  2. jcsd
  3. Mar 10, 2017 #2
    This design would work in principle. The tires could have permanent magnets positioned throughout.
    A problem might be in getting the magnetic field close enough to the tire - even with tread wear and when the tire is dirty, iced up, etc.
     
  4. Mar 10, 2017 #3
    At this link: http://www.marathonelectric.com/docs/SyMAXFAQ.doc
    I found this:
    Of course, in this application many of the advantages of using a PMAC will be severely offset by the required geometry of the rotor being a spherical tire and the inner stator surface being a section of a sphere.
     
  5. Mar 10, 2017 #4

    RonL

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    It has many great possibilities, but can one imagine a road free of metal fragments of all kinds sticking to the tires and what the magnetic track path would look like with all the sharp points of metal sticking straight up.
    Copied the picture below from this site.

    magnet.png
     
  6. Mar 11, 2017 #5
    Why should the metal fragments stick to the tires. won't the car and tires have repulsive magnetic fields to stop this..
     
  7. Mar 11, 2017 #6
    Only other magnets can be repulsed. Metal is only attracted to magnetic fields.
     
  8. Mar 11, 2017 #7

    jack action

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    I think it is assumed that everything will be within the tire. The electromagnetic field comes from within the tires themselves and the permanent magnets are on the car. This way, it would be feasible to make it work similarly to your maglev example. Magnets on the car in "front" and "behind" the tire (what ever direction that maybe) that push and pull to make it rotate.

    From other videos I've seen, this is more of study case to show what is feasible in tire technology such that other area can research more in their own fields. You know, like: «Wouldn't it be wonderful if tires were spherical, then we could adapt our technology to it.» Well, wonder no more, some people are seriously looking into that right now.
     
  9. Mar 11, 2017 #8
    So what you guys are saying is that this is actually possible? I really didn't think it was. If this is possible, the only advantage would be the maneuverability at low speed. I can think of many disadvantages.
     
  10. Mar 11, 2017 #9

    RonL

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    I had to go back to the video and pause it in order to read the captions (didn't do that the first time) so I'll retract my comments about how much trash would be picked up magnetically.
    However having driven all kinds of vehicles on all types of road surfaces, for almost 60 years, I still have some doubts about the level of perfection that would need to be maintained in order for this to work ?
    I do like the idea and I think a less expensive system might be possible using compressed air to suspend the vehicle over the tires, friction transfer to drive the wheels. (but then I guess I'm resisting the future too much in my old age) :wideeyed: :rolleyes: :biggrin:
     
  11. Mar 11, 2017 #10
    To me, even if you could get this to work, the only advantage would be the low speed maneuverability. Cons would be plentiful. Cost would be astronomical. I would be very concerned with reliability. Unless the ball can collapse a little, the contact patch would be tiny. If it can collapse, I think it would have to collapse so much that heat would become a problem. Auto makers spend a lot of time and money trying to get as little unsprung (or in this case, unmagleved?) rotating weight as possible. Unsprung is important for ride quality and traction safety. The heavier the tire assembly, the more it "bounces" over bumps causing a safety traction issue. Rotating weight is important because it takes longer and more energy to speed up and slow it down. These spherical tires would weight a LOT. Yes you get rid of the rim but you have about 3x the rubber and a bunch of heavy as hell magnets. It would take a ton of extra energy to accelerate and slow the car and it would do it MUCH slower that a traditional car. Driving down the road with a sudden crosswind would likely cause a uncontrollable lane change. I think stealing would be an issue because they are not actually connected to the car and they would be way more valuable than a regular tire. We are focusing on efficiency lately and this thing is not efficient at all. The amount of energy require to levitate the car and rotate the tire would be through the roof. How do you power the magnets in the tire? This would be very difficult and add even more weight. Lastly, this is one of the biggest violations of the K.I.S.S. principal ever.
     
  12. Mar 11, 2017 #11
    Don't you are right.
    So even if the field is repulsive the tyres will still pick up metal.
    They might be better on a hoover.:smile:
     
  13. Mar 11, 2017 #12
    Either the batteries would not produce or hold enough power, or whatever generator used would not produce enough electricity. Presently we are looking at better batteries, but a far more productive course might be to look at better electrical production bypassing a battery completely. When this is achieved all new sorts of power plants are viable
     
  14. Mar 12, 2017 #13
    Don't electric cars these days already have independent motors on each tire? If that's the case you could have them rotate just as well as those ball tires, but with much less pain. I think the major reason for cars not being able to turn their wheels 360 degrees is because of the common drive shaft.
     
  15. Mar 12, 2017 #14

    RonL

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    My limited understanding of electrical induced levitation gives me the impression that not a lot of electrical energy would be required to hold the body above the ball wheels, but changing of load weight and distribution would pose a real challenge.
    As stated, I like the idea but think it is quite limited in many ways. I will continue to think air suspension might be more practical and see the extension to six or eight ball wheels, which might give a vehicle that can drive across lakes or still water conditions, but that starts to take the thread in a wrong direction. (sorry) :frown: :smile:
    Maybe someone can explain the concept of how much electrical energy would be needed to levitate, I have a pretty good idea of the drive forces that would be required.:smile:

    ps. I almost forgot to put my thought in, which is that the ball wheels will completely eliminate the suspension alignment problems that all current vehicles have now. :rolleyes:
     
  16. Mar 12, 2017 #15
    What about all the cons I listed in post #10? I personally really don't want this to happen. I just was curious if it was even possible.
     
  17. Mar 12, 2017 #16

    RonL

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    As an electric design, I pretty well agree with most of your cons, lite-weight and large air gaps do not go well with electric power transfer.
    As a mechanical design floating on air over the ball tires, using some form of friction transfer, I see a lot of potential. That comment deviates from the OP so I will stop with that. :smile:
     
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