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Spherical Motor Creation
There's an interesting story concerning the development of a circular based-motor. What's interesting about this motor is that it can spin to apply force in three dimensions -- some researchers at Johns Hopkins unveiled it recently. It looks pretty cool -- many magnets involved in it.
Suddenly the engine is the tires. :-) The only engine you'd need on the car itself would be something to generate the power for the magnets.
Remember, you saw it here first. So dig back here when someone tries to patent this. :)
- the Crazy Fraggle
There are basically two applications that spring to my mind:
First, an "omnidirectional" wheel. Ok, for this you do not need 3D as 2D will be sufficient. Plus you need a pretty clean surface, else the motor suspension = drive axis will be clogged up with dirt. A smooth "wheel" (=ball) will be better for high motor efficiency, but will increase slipperiness, too. So I guess directly using this drive as motored wheel is not the best choice.
Second, yu can cinstruct a spherical joint similar to the human hip or shoulder joint. With this you limit the movement arc to a cone with ~140 degrees opening. Spherical joints are especially interesting for major static/suspending joints - like hip or shoulder. But there are the shortcomings of this design:
The major problem will be the low torque and missing self-locking. Self-locking means, that the system does not have to use energy to keep the joint in that position. Excellent example for this is the worm-gear: nearly completely self-locking and high torques possible. In comparison this 3D-"freely spinning" joint is a (low power) direct driven, low-torque, non-locking.
As you have to use distributed permanent (=low power) magnets, the torque cannot be increased much (compared to classical e-motors with exclusively electro-magnets). Plus - as you need a high number of e-magnets - the motor is quite heavy.
All in all a nice idea, but not a good choice for most current uses IMHO.
-DVK
"The right to figure things out for yourself is the only true freedom everyone shares. Go use it"-R.A.Heinlein
Perhaps a battery, capacitor, or something of that nature could be used inside the ball, along with a coil of sorts, so that induction could power internal electromagnets. The coil would input the energy into the battery/capacitor, (with a AC to DC rectifier) wich in turn would smooth the current flow, then on from there to the coils inside the sphere. There surely has to be a way to do that without interfering with the magnetic fields associated with motion. A high frequency switching between the motion magnets and the charging magnets perhaps? That may even allow the electromagnets themselves to recharge the battery, a regenerative system of sorts. As the AC current switches between posative and negative current, a simple diode could allow one way to charge the battery, and the other swing to charge the magnets. I suppose that some inefficency has to be accounted for, that would be almost like perpetual motion, so some coils could do double duty while others are strictly charging coils, and could provide current to the battery/capacitor on both cycles.
It may help extract more torque from the system, but without some sort of physical gear reduction, it will probably still consume high power while having the ability to do very little work. Still and all, it's range of motion and accuracy may prove to be more important in many applications than sheer power.
"Everything that can be invented has been invented."
--I assume full responsibility for my actions, except the ones that are someone else's fault.
Think about it, you couldn't just have loose bearings beneath you - you'd need something that held its position and could move any direction to correct your movement to make it feel as if you're on solid ground.
If you could make them about half the size of marbles, wow, the possibilities would be endless. That one idea of the spinning discs on tables to rearrange things is already outdated. This would rock!
That's going to happen to humanity eventually. We keep packing more and more into less and less (for example, more schooling in shorting time frame - you easily knew twice as much by your senior year in HS than your parents).
We're going to need to take the smaller and more trivial tasks off our hands. There will be no alternative. What's the solution? Certainly not a group of people engineer to be simple/stupid (Brave New World), but rather, machines.
Right now, robots are unfriendly, imposing, and insanely clumsy. We *need* them to be able to move and act naturally as we do. We need them to not be scary. We need them to be more fluid. They'll inevitably have to interact with us in a personal fashion.
And if you're still unconvinced, think about the applications of robotics technology with fluid, human-like motion in medicine. Wouldn't it be nice to give amputees brand new arms that move flawlessly when compared to the real thing?
I'm tired, so I'm not going to go on any longer... but wow, the possibilities!