> How on earth can a single wheeled device right itself from a lean?  Big
> gyroscope inside it?

Acceleration and/or steering.
Scary.

IF you have the ability to rotationally torque it OR to change the
drive direction relative to the current line of travel you can make it
try to lean in or out.

If you accelerate it along the current line of travel and it is
"leaning in" it will start to lean in less. On a motorcycle, taken to
its common uncontrolled conclusion, this is called "high siding".
:-).
I long (long long) ago read that the way to practice highsiding is to
put on your helmet and leap head first from a house roof.

1. Interesting test for those who are not aware of what happens:
Ride on bicycle or motorcycle.
Ride in straight line at steady speed - coasting is fine.
Place palms of hands gently against rear of handlebars on each side.
ie do not hold - just touch.
Press forwards GENTLY with eg right hand palm.
Observe.

The handlebars will do something which seems to break the laws of physics.
The bike will do something interesting.

2. DO NOT do the following
DO NOT
DO NOT !!!!
Silly fool ...
Ensure medical insurance is up to date.
Ensure will is up to date.
Wear a helmet and padding.
Ride in straight line at constant speed.
Ensure insurance, ...
Reach across with left hand and hold right handlebar.
Reach across with right  hand and hold left handlebar.
Observe.
If alive and nit under medical care, marvel at human motor responses
and what the brain can and cannot do
Report, if still alive.

Slow speed on soft surface on bicycle MAY be worth the experience.

So, you think that YOU can do it.
Don't you!
Don't you !!!

Don't.


       Russell
--=20
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