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Spherical Vehicle

  1. Mar 6, 2006 #1
    Spherical Vehicle Design by Michael W. Reed

    I have been thinking this idea over for a few months now, and I thought that it was time to ask for help.
    My inspiration for this idea came from trying to think of the most all-terrain vehicle possible. Once I realized a sphere would be it; I started to think about the possibilities.
    I started with a transparent sphere; being turned inside by an axis across a diameter; going through the sphere, and attaching to some half-sphere chassis on the top half; the motor and driver being in the center. I saw the need for a weight hanging down, somehow, from the engine, both for stability and keeping the sphere the only thing spinning, and to somehow shift left and right for turning.
    Next, I realized that, first; the turning wasn’t going to work, if the weight shifted to the side; the sphere would not turn, as I had imagined, but also continue it's straight forward course (hello momentum!).
    And also, the driver needs to breathe! At this point, I was just going to have an air tank in there, or something, I wasn’t sure. Also, notice that the previous sketch is without the outside chassis, that can’t work, it seems.
    As far as the "hello momentum!" problem, I realized that the axis would have to slide, to keep balance.
    ... but how do we accomplish that? If the axis slides, a new method of attaching the axis heads to the sphere is needed. This seemed rather tricky, because dependant upon where the sphere surface is, during its spinning, the axis must be able to grab hold, and detach from the sphere anywhere, and the attachment can't be too hard, it must allow for a relatively slow transition of spin direction, and we must maintain visibility.
    It seemed the best idea was to use electrical magnets on the axis heads. My first idea was to have metal plates on the outside of the sphere, being always somewhat attached with a minimum of charge, having them float around on the outside. No, that wasn't going to work; how do I keep them from getting knocked off? Put the whole thing inside yet another sphere, with some kind of transparent, gluey substance in between, so that the plates can float around, while maintaining friction with the inner sphere? No, too damn messy, not too mention the problems with entering/exiting. I guessed that the sphere, itself should be made out of metal; I was thinking super thin titanium (or some alloy), which should be transparent enough.
    Besides all that, how exactly do I accomplish the said axis sliding? It seemed I would have to add more axis. To be able to have complete rotational control; it seems we need 3, or rather 6, if, and I think it’s needed, independent, although, of course each inline axis would be in the spinning the same direction. To turn, the different axis heads grab hold harder or softer, combined with axis spin, and the heads should, it seems, also be able to somewhat disconnect from the axis, while still grabbing the sphere, to allow the inside sphere to turn as well, to allow the driver to face differing directions.
    Granted, the mechanical workings of the transmission, and programming for the engine computer will be complex and tricky, but it seems possible.
    What about the top axis, how does it get around the driver? I guess it should be split up, two rods coming out of the engine on either side of the driver, and then rejoining over their head.
    Another issue is shock absorption. While a sphere is the most structurally stable object, it also tends to bounce off of things it collides into. This bouncing multiplies the shock given to anything inside of it. So I thought; why not have the axis also be shocks?
    The shocks would also have to allow for pull, as when the center stuff goes one way; one side squishes, the other stretches.
    Also, as is seen in the sketch, the axis heads need to be able to swivel somewhat, and smoothly glide over the spheres inner surface.
    Next issue: debris. How the heck do I keep all of the crap I’m driving over off of the sphere, so I can see? Titanium is, itself, mildly self-cleaning (although somewhat dangerous due to possible (though unlikely) contact with deuterons (it becomes radioactive)), but not enough to be able to see whilst driving through mud.
    So, how about the additional sphere outside idea, from before, only this time the outer sphere is a thick, wire frame, of sorts.
    I'm not sure on the sizes of the Xs and Y, and… how would I get out of the outer sphere? I guess that the frame could be chain-linked.
    The squares in between the segments would be connection points, or maybe the segments could just attach to each other? With a chain-link, I could detach certain links, somehow, and create a door for myself. Anyway, with this setup, I could install hoses to spray off debris.
    Also, how do I get out of the inner sphere?
    Also, to keep the center sphere centered, I would need some kind of axis bridge.
    I guess it only "shocks" in between the spheres. OK, but then the outer sphere's size would have to get be relative to the speed available for travel, which I'd hope could be pretty fast, at least 100 m.p.h. I'm not sure of the size.
    Also, that whole breathing issue, yeah, it could be an air tank, but that’s… sketchy. I guess I could split the inner sphere at the halfway line, and have some kind of air filter diving the halves.
    Also, the axis heads, and inside surface of the outer sphere need to be coated with a super non-friction material, and the top axis needs a constant, slightly greater magnetic force, to hold the inside up, and reduce drag on the bottom. And, also, when parked, the vehicle will have to be supported somehow.

    *That is all I have come up with, so far... comments?

    I have attached an MS Word 2000 .doc file of this including some rough sketches.

    Attached Files:

  2. jcsd
  3. Mar 6, 2006 #2


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    Mm. I'm not going to open a word doc. No offense - call me paranoid. You might do better to post it and the images as HTML.
  4. Mar 6, 2006 #3
    A few of the sketches

    OK, well, I don't currently have web space to link to the sketches, but here are three of them (the limit on this site). They are very rough, drawn in Paint Shop.

    Attached Files:

  5. Mar 6, 2006 #4


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    You don't have an ISP that gives you storage?
  6. Mar 6, 2006 #5


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    This sounds similar to the monowheel in concept, with the passenger inside a circular drive system. Here's a monster web page (beware dial-up users) with a huge number of them ending with some recent ones that have gotten press on some TV shows.


    The big problem is the lack of torque and visibility. If you are traveling over dirt or mud, it will stick to the traction surface. With a clear sphere, this IS your visibility.

    The lack of torque is a function of the mass and how far down from the center of the sphere it is, and it would be simple to calculate. For even a short wheelbase vehicle like a motorcycle or a Jeep, this is going to be substantially larger figure, meaning you'd be able to apply enough torque to the traction surfaces (tires) to spin them before the vehicle itself would rotate. Instead with the mono wheels, too much powered acceleration or braking can cause occupant to spin around inside the vehicle.

    Also, how do you see through a metal? Aluminum foil is thin enough where its weak enough to push a finger through it. A small rock or crack in the pavement would wreak havoc on a thin metal. Maybe a lexan or plexiglass solution with some sort of coating to resist scratches would work better.

    NASA did something similar, the tumbleweed rover for Mars exploration.
  7. Mar 7, 2006 #6
    There's another potential problem with a spherical vehicle. If you try to stop suddenly, or go up a very steep hill, you could endo up with the whole thing, including the people inside rolling. In monowheels they call it "gerbiling" because it's similar to a gerbil who tries to stop sudenly on his exercize wheel. The whole wheel keeps going around, with him spinning around in the middle.
  8. Mar 7, 2006 #7

    Dave - no, I'm currently stealing an internet connection from a cafe across the street.

    Cliff - On visibilty; the transparent sphere is on the inside of another wire frame type sphere which is thin from the drivers perspective, thick from the side, if you can picture, this sphere having a... maybe 3 feet larger radius. Hoses could be installed on the inner sphere, installed like windshield washer nozzels, or something. On torque, and the inner spinning, also responding to SaMx; I realize that this is a big issue, maybe the biggest. The second sketch is on this inner spinning topic, depicting the axel heads on both sides of an axis (non-friction, electrical magnets, more or less connecting, but not LOCKING to the wire frame) somewhat connecting to the wire frame, while detaching from the axel, but... you know, perhaps that's not really even needed, because remember, the axel heads aren't actually CONNECTED to the outside sphere, other than magnetically, they are coated in a super-non-friction material, as is the inside of the outer sphere. This super-non-friction connection together with a low-seated engine (weight) should counteract the "gerbiling" effect shouldn't it? yes, in more extreme cases, the inside stuff would start to spin, but only for a short while, it seems. On seeing through the metal; I had spoken of thin Titanium, which would be able to resist denting, but the transparent sphere is on the inside anyway, so it could just be fiber glass or something. On the sketches, the first is my original, and very bad concept, the third is a more recent concept. Here are some more sketches; the outside sphere grate sizes, that I am unsure of; shock movement of inside stuff; and outside sphere chain link

    Attached Files:

  9. Mar 8, 2006 #8
    OK, I just realized that what I said didn't make any sense, concerning the inside rotation... this is tricky. Perhaps there could be an additional cylinder surrounding the axels, that could be turned in the opposite direction of the axel somehow, no no no... yeah, this torque/girbiling issue might be the catch after all. Well, if the outer sphere was smooth, I guess maybe there could be little wheels on the ends of the axel heads that correspond to the spin direction(s), and could be made to provide a bit MORE torque than the current spin direction, could be turned on the axels heads NOT currently being used for sphere movement, and only supplying the extra torque if and when the inside stuff starts spinning instead of the sphere... possible?
  10. Mar 8, 2006 #9


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    Michael - lets put some basic numbers down shall we?

    Lets say you have a center of mass of 300lb at a radius of 3ft from the center, that's 900ft-lb of torque. Any more than that and gerbil will happen, and just the impulse from releasing the clutch too fast could cause it but we'll ignore that for now. So lets say the outer sphere traction surface is a 4ft radius, which works out to 225lbs of force applied to the ground.

    Lets say we have a Jeep,and the motor makes 200ft-lb of torque. Transmission has 3.0 1st gear, transfer-case has 2.5 reduction in low, differential has 4.0 reduction, this all works out to 30:1 reduction, thus making for 6000ft-lb of torque to the tires, lets say they're 3ft tall or 1.5ft radius, or 4000lbs of force to the ground, 1000lbs per tire.

    So a basic 6 cylinder off-road Jeep offers a lot more forward propulsion capability for off-road use and climbing hills. In this example 18 times more forward propulsion at maybe 5 times the weight means its force/weight ratio is still 3.5 times better than the sphere.
  11. Mar 8, 2006 #10
    Cliff - Yes, I thought about it some more and it seems that you're right. Oh well, it was a fun thought experiment.
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