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Practical Magnetic Levitating Transmission Gear System Loses Its Teeth
Zothecula writes: A new transmission device that uses magnetic levitation to almost completely eliminate friction and wear has been developed as part of the MAGDRIVE research project, a collaboration of seven European nations. The creation of the unit entailed the development of a magnetic gear reducer and corresponding frictionless magnetic axles. Aimed primarily for use in spacecraft due to its extended mechanical life, the system is also adaptable for use in automobiles, railways, and aircraft.
On 5-10 years back about classic cars from some museum in SoCal or something.
The 3 primary vehicles they discussed were:
A 1900s era Battery Powered car with a 25 mile range.
A Steam powered car capable of 'gas-like' performance, given ample 'warmup' time.
And a 1920s or 30s electrocoupled automatic transmission car that I believe used increasing rotational speed to more closely couple the engine to the output shaft (Can't remember if it also had gears or if the coupling mechanism doubled as the 'gears'.)
Point being: So they're finally getting back to R&D on 'non-mechanical' coupling mechisms in modern vehicles. Yay! Only took like 90 years.
Way more efficient than gears for loads it's designed to handle - but it's not meant for heavy lifting; the "magnetic gears" will "slip" if the load is too high, and in this case "too high" is quite low (think force required to move two magnets oriented in "repulsing" way against each other).
If you couldn't move high forces with a transmission like this, then you also couldn't generate them with an electric motor, because you couldn't hope for the magnetic fields to turn the stator against high loads.
OTOH, stuff like lander wheel bearings or drills for picking samples are better handled with normal bearings that can take much heavier loads.
What happens when you put too much torque through a drill? You shatter your bit. What happens when you put too much torque through an axle? All kinds of exciting things can happen, check out some four wheeling videos. There's lots of reasons why some slip designed into the system is not an undesirable thing.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
The question is, how much force can it handle? Large electro-mags can pick up entire cars. Sure, it's huge, but it's lifting up 2700 lbs+. Also the surface area is large because the objects surface area is large. If a really high powered small electro mag was used, it would just rip out that piece of metal.
How many pounds of force can the small one withstand? It's possible using two small unpowered magnets to easily make one that could crush a hand if a hand was implace and restraints were let go on the mags.
I imagine it could potentially with a little voltage withstand a lot of torque, and limited slip to prevent spin outs, it might be fantastic for rovers.
They're often in lower gravity environments to begin with.