Stabilizing robot on bridge with gyro or accelerometer

[ksafin]

Can't say I've read all these long posts but -

OP said to use a button that'll make the robot stop when in horizontal;

What about holding a button and the robot will automatically adjust itself to get into horizontal, and if it is in horizontal, it'll stay at 0?

Kind of like an auto-leveling application, instead of manual operation and leveling.