Stable / Level / Acc / Angle
Requires: Gyroscope, Accelerometer.
In ANGLE mode (previously known as LEVEL or ACC mode), the board will attempt to set pitch and roll according to the absolute angle of the input sticks. For example, if the pilot sets the roll stick to 5% right, the aircraft will attempt to maintain a "5%" right roll. In this mode, "centering the sticks" will cause the aircraft to attempt to level itself.
As with any auto-leveling function, this mode requires that props and motors be well-trimmed to eliminate vibrations that can interfere with the Accelerometer readings. Likewise, the frame must be stiff and vibration-free, and the accelerometer must be correctly positioned at the center of gravity. These are the requirements for ANY multirotor to have a perfect autolevel, not only for MultiWii.
