The Segway is equipped with three keys when purchased.  These different keys set a maximum speed for the rider.  Originally I thought that the Segway should have an unlimited speed, as far as you tilt it should keep speeding up right??? 

Looks like I was totally wrong.  But how?  How does a key limit the speed if it's supposed to catch you no matter how far you tilt.

In theory, if you follow the physics behind it, while  you keep tilting there needs to be an equal and opposite force (motor speed increase) to catch you from landing on your face.  The only thing to slow you down is the rider pulling back on the handlebars to upright the scooter.  However it is totally impossible to lean down to say 20 degrees from the ground, you'd have no way to pull up at that speed nor control your direction. 

What has been built into the Segway program is a "simple" detection that you're over the maximum tilt or speed for that key.  When you hit that angle or speed (it's defined as speed, but is controlled by your angle of tilt) speed increases so that you are pushed up to an angle and speed that isn't so dangerous.  It all works according to skill level so that the more experience drivers can allow themselves to tilt further.

I'm gonna need to make a n00b key for myself.  Craig can play with the "Godlike" difficulty key.