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by michaelt 1626 days ago
Single wheel vehicles have no brakes worthy of the name.

After all, when you brake hard with a car or motorbike or bicycle, it's the front wheel, well in front of the centre of mass, that does almost all the work.

In a single wheel vehicle, the wheel well in front of the centre of mass.... isn't there. In a unicycle that means you're flying off the front (it's even worse in a monowheel) so you'd better not be going faster than a man can run.

1 comments

... which is why you lean back on these to brake, to shift your center of mass back so the wheel can slow you down. same thing in reverse for accelerating, otherwise you'd see people fall off non-stop at the beginning for the same reason you claim they can't stop.

your stopping speed is limited by how fast it can decelerate you, which is essentially the same as how fast it can accelerate you. it's not super fast to stop, to be fair, but neither is a bicycle going at high speed (though I'd expect the bike to be a little bit quicker to stop).

My issue with EUCs is the complete lack of options in the case of power cutting for any reason, whether it be overheating or low battery charge or a resistor burning out.

Leaning back is not an option once the motor stops pushing the wheel towards you - it’ll roll and then tumble to a stop much more quickly than air resistance slows you down, so you’ll fly off the front.

I’d like for there to be a magic solution to this problem since the size of an EUC is very attractive. Rolling to a safe stop on my electric scooter is preferable in the meantime.

yeah, an instant loss in acceleration would certainly make you eat pavement in many cases. definitely a fair concern. I might claim that "I hit a rock slightly larger than that small rock I can usually roll over and now I'm in an impromptu pole-vault competition" is a more common issue with small scooter wheels than random power losses, but there's more personal control over that. (personally: crossing train tracks were my #1 fear and #1 fall cause on scooters)

either way, safety gear safety gear safety gear. especially since basically all these electric personal mobility enhancing whatsits are horrifyingly injury-prone compared to anything the size of a bike or larger.

If you need to stop super fast you lean back so hard you're actually dragging the tail. There's a reason a lot of people put additional plastic armor on the bottom of these things.