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Behold The Hyundai Uni Wheel. Transportation May Never Be The Same
(cleantechnica.com)
This is a most excellent place for technology news and articles.
Fascinating, but in the video they very quickly swipe off-screen that the top speed their new system was able to achieve was 120 kph / ~75 mph.
I imagine something like this would have to be limited to vehicles that never need to approach speeds above that on a highway, so maybe busses or indoor shipping & receiving vehicles.