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Balancing Monowheel

Like a regular monowheel, but rider near top, not bottom
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(+2, -4)
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First, a bit of background: A "normal" monowheel is a one-wheeled vehicle similar to a unicycle. However, instead of sitting above the wheel, the rider sits either within it or next to it. The wheel is a ring, usually driven by smaller wheels pressing against its inner rim.

Since the rider's weight is near the bottom, braking results in the rider leaning towards the road; accellerating causes the rider to tilt skywards. This is the exact opposite of a balancing vehicle, like a segway or unicycle.

What if the rider sat in a seat which hung suspended from the "upper" part of the monocycle's wheel? For ease of use, the vehicle would need to balance itself, as a segway does, but that's not technologically difficult.

Steering, and left-right balancing, would (probably) need to be done by the rider shifting his weight, but since tall objects are easier to balance than short ones, that shouldn't be too hard either. Alternatively, making the vehicle a dicycle (with both wheels close together) could make the vehicle left-right stable.

goldbb, Jul 14 2009

Wikipedia on monowheels http://en.wikipedia.org/wiki/Monowheel
[goldbb, Jul 14 2009]

Wikipedia on dicycles http://en.wikipedia...i/Dicycle_(vehicle)
[goldbb, Jul 14 2009]


       The dynamics are not so differnt from a segway. If a Segway was hacked to just accelerate, without waiting for the user to shift his weight, the Segway would tilt skyward too. Difference is: In a Segway you have to tilt forward first, the acceleration brings you back to vertical. In a monowheel, you do not need to tilt forward first, because gravity will bring you back to normal after the acceleration. - But you could, if you wished so. To take the rider of a monowheel above the axis of the wheel forces him to tilt first, to adjust for pos/neg. acceleration, so it is kind of an unwieldy Segway.   

       Could you list the bright points of this venture?
loonquawl, Jul 16 2009

       //bright points// being the person with the videocamera. it would have to be a *big* monowheel to let you stand up to tilt forward.
FlyingToaster, Jul 16 2009

       Won't the rider now end up leaning towards the road when accelerating and tilting skywards when braking, to about the same extent as before (but reversed)?   

       I agree about tall objects' being easier to balance, though. Having ridden a tall bike, the feeling is one of serene stability, with the ability to ride very slowly without losing balance.
spidermother, Jul 19 2009

       Monowheels have a centre of gravity below the rotational centre. This makes them more stable, no matter how tall or short they are. Further, any action, either braking or acceleration, sends the majority of mass up an incline, countering gravitational forces. So it self corrects. Your system suffers from either positive feedback loop or aggrevation of the dominant force (gravity). Take splints and bandages on your first voyage.
4whom, Jul 20 2009

       Yes, regular monowheels do have a center of gravity below their rotational center, and do not need self-balancing.   

       If one made a *modified* monowheel, with a center of gravity above the rotational center, then it would be appropriate to incorporate a self-balancing device.   

       Try to picture an oversized bicycle wheel, with a rider sitting in a seat which is hanging from the uppermost portion of the wheel.
goldbb, Jul 20 2009

       What you're basically saying is mix the two bad halves of a segway and monowheel?   

       You're going to make the rider pretty sick leaning onto the desired acceleration, and also it's goingto be a jerky ride, as to brake the wheel would have to accelerate in front of the rider before braking could occur!   

       The rider will also be deprived of a straightahead view, as in a regular monowheel. The maximum acceleration (theoretical for both accell and decel) will be 1g, only if the rider's mass is held at the exact rim and the wheel's weight is negligible.
Skrewloose, Jul 20 2009


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