Johnny B Good wrote:
It's the use of rare eath magnets in those tiny motors used in drones
that allows them to achieve more useful endurance times out of their LiPo
battery packs (much greater power to weigh ratios out of what generally
makes up most of their mass).
Indeed, I'm surprised that they haven't replaced the complex mechanical
transmissions that seem to still curse most electric cars today by being
incorporated as part of each wheel where the transmission is entirely
heavy duty cable (with a specially flexible section to feed the power
past the suspension to the hub motors), reducing the 'gearbox' to nothing
more than a sophisticated program controlled heavy duty switch mode
converter. This might not suit the handling demands of a more extreme
performance road car but it should do nicely for a typical family saloon
or small runabout.
Given the huge environmental costs of rare earth element extraction its
maybe no bad thing that theyre not being used in the booming electric car
market. If Tesla can manage without them I reckon thats good enough for
most of us.
Additionally, €śmotor in hub€ť adds hugely to unsprung weight (which isnt
supposed to be a good thing). I appreciate that this might be mitigated by
the use of rare earth magnet motors but that brings us back to the
environmental problems again.
As Im sure you know, €śrare earth elements€ť arent actually rare, just
fecking difficult, dirty and expensive to extract.
https://e360.yale.edu/features/boom_..._toxic_ri sks
Tim
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Please don't feed the trolls