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Commander Kinsey Commander Kinsey is offline
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Default How can you possibly fall off a self balancing scooter?

On Thu, 24 Jan 2019 22:46:36 -0000, NY wrote:

"Commander Kinsey" wrote in message
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On Thu, 24 Jan 2019 21:57:01 -0000, NY wrote:

"Commander Kinsey" wrote in message
My point was why does the rider need any skill whatsoever? The device
should move under your centre of gravity automatically. Perhaps they
have
to be calibrated, and people falling off are borrowing someone else's of
a
different height or weight?

I wonder whether a lot of the problems with people falling off are that
they
are scared when they tilt too far, and instinctively try to correct by
adjusting their position instead of standing still and letting the
scooter
do the adjustments to keep you level, or else they panic and jump off.


When I tried one, when I lost my balance it appeared to scoot off in the
wrong direction - eg I fell over backwards and the scooter went forwards.
No idea why - it should have been trying to power itself backwards
underneath me.

I probably went through all those stages in the first 30 mins of getting
on
a Segway for the first time. But after a while you develop and refine the
muscle memory to work out just how much you need to move to stay level
and
not to "fight the machine" - similar to the skills you acquire when you
learn to ride a bike.


But with a bike, you have to balance, with these devices surely they
should be doing the balancing for you? You should never actually fall
over, because no matter what you do, it moves under you.


I imagine the control logic has to be very clever because it has to cope
with a human standing on it. If you had a rigid human-sized figure on it,
and you pushed it so it was about to topple over, the logic would easily
correct for this.

Now substitute a real person with knee and hip joints, able to adjust their
own balance sideways and fore/aft, and liable to try to make their own
corrections which may counteract those that the scooter tries to make, and
you've complicated things a lot. A Segway, like a bicycle, is inherently
unstable and needs advanced control logic (whether human or computer!) to
keep it upright and to make corrections. I understand that it has now been
found to be a myth that the gyroscopic effect of the wheels plays much of a
part in keeping a bike upright, and that it's all down to minute adjustments
of the steering.


I knew steering played a big part (I thought about 50%) because I've seen a trick played where people are given bicycles with fixed steering, and it's very difficult to balance on them. I'm sure the wheels play a big part too - if you remove a bicycle wheel and keep the hub, then spin it holding the wheelnuts, it's difficult to turn over. Mind you, maybe that's not enough to prevent the weight of the rider falling over too.

I wonder how long it will be (if ever!) before the UK allows Segways etc to
be used anywhere other than private property - ie anywhere that the public
might be. We seem to be very backward in allowing them,


They can go anywhere already - that stupid law is not enforced.

whereas an unskilled
person on a bicycle or roller skates or one of those bloody mobility
scooters can easily injure a bystander. I still have the bruise on my hip
and my foot


I'm sure you'll live. I do find it amusing that the faster species of scooter (they have 4mph and 8mph versions) are not allowed on pavements, when I can legally run on a pavement at well over 8mph.

where an old biddy reversed into me repeatedly in the
supermarket ("the scooter won't move, so I'll keep trying until it does")
and then drove over my foot. And she had the audacity to swear at *me*, when
I was trying very hard not to swear at *her*. She rode off in a huff and hit
a display stand. Poor woman wasn't safe to have control of a scooter.


I find more problems with pedestrians in supermarkets. I was pushing my trolley along quite normally the other week when someone walked backwards into the end of it. He then yelled at me "You could have said something!" So I replied "Like what? Get out of my way you incompetant moron? I hope it's your wife that's driving home...." She was somewhat amused, and he was not.