[ZZII 527]

This sounds like a really fun project! Keep in mind that keeping a mini Segway balanced is actually more difficult than the real thing. Think about trying to balance a pencil on the tip of you finger versus a broomstick. But it is by no means impossible.

As for getting it started: When it's normally balanced and stationary, the drive motors are constantly canceling out minor displacements forward and backward. If you suddenly ALLOW a small amount of forward displacement (while still restraining backward tilting) it would naturally fall forward a bit. It would provide enough torque at the wheels to balance this offset and start moving forward. When you are done accelerating, take out the offset and it should return to constant velocity. Easier said than done...but it might be a starting point.