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Wheeled Vehicle Yo-Yo Despin Emergency Braking

... dangerous for everyone except the vehicle occupants
  [vote for,

Rockets use yo-yo despin as a way to cancel spin. I propose such mechanism is implemented on all wheeled vehicles: trains, cars, bikes, wheelchairs etc. This is a space age "safety" mechanism (quotes must always be used during promotion of this product)

1) Translate the wheel spinning motion from vertical to horizontal. This spinning motion will spin weights tethered to a pole sticking up above the vehicle occupants.

2) In case of emergency release the counter weights and let them fly out. This will stop the spin of the wheels

3) Vehicle comes to a safe halt ... the surrounding damage is just an externality.

If you are not sure what a yo-yo despin is see link below

ixnaum, Apr 18 2016

Yo yo despin of a sounding rocket https://www.reddit....g_rocket/?limit=500
[ixnaum, Apr 18 2016]

complimentary autowheeeebile Autoweeeebile
A computer algorithm could decide whether it's safer to use yo-yo despin or wheee mechanism [ixnaum, Apr 18 2016]

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       I am torn between giving you a (+) for the idea or for the first link, so I can only give half a (+) for each.   

       I regret, I have but one loave to give.   

       Wonderfully pointless, except for unicycles on tightropes (where you wouldn’t need the vertical-to-horizontal transmission and extra wheel), which are themselves wonderfully pointless. Would make a good performance art/engineering car for Burning man ca. 1995, back when it truly was a TAZ.   

       I think the idea suffers from a failure of mechanical imagination, though, because a yo-yo despin arrangement can be regenerative. So rather than releasing the tethers, just disengage their spool/disk from the cars traction wheels, snub off its little remaining speed with its regular friction brakes, go do you business (remembering to duck), then, after you get back in, reengage and winch the yo-yos back in to get back to your original momentum.   

       One shouldn’t picture this scary art car as looking much like the satellite payload yo-yo despiner in the liked video, though, because the momentums for a car are much greater. Assuming a little, 1000 kg (without the yo-yo bobs) car with a speed of 25 m/s (about 56 MPH), to keep the bobs sub-sonic, they’d each have to be over about 80 kg. So, assuming a “little remaining speed” of about 1 m/s and 10-to-1 gearing between the wheels and the yo-yo disk, we’re talking about a compact car spinning a pair of 80 kg masses on about 30 meter long tethers. What’s not to like?
CraigD, Apr 23 2016


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