Flying wing with rudder.

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Hi!

Is there any possibility to use APM2 in flying wing (elevons mixing) with 
rudder control?
I cant found information about this anywhere.

Mateusz

Original issue reported on code.google.com by jezu...@gmail.com on 3 Jun 2012 at 6:34

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Please ask questions elsewhere. This section is for bugs.

There are two ways in which ardupilot uses the rudder:

The first is that it attempts to counter adverse yaw from the ailerons. 
Basically, the lowered aileron is draggier than the raised aileron, so ailerons 
induce yaw counter to the direction of turn while the plane is rolling. When 
the plane is done rolling, the ailerons usually have to be set opposite to the 
direction of turn, in order to prevent overbanking.
This is a direct mix between aileron and rudder and is accomplished in by 
KFF_RDDRMIX. Set it so that it eliminates adverse yaw and *nothing more.*

The second is trying to drive the Y (lateral) accelerometer to zero. This is 
accomplished using the YW2SRV PID. If your Y accelerometer significantly 
deviates from averaging zero in a turn, you might need to use this. 
Accelerometers are noisy, so I recommend just using the I and IMAX terms. Set I 
to something like 1-3, set IMAX to something like 35. It shouldn't be thrashing 
the rudder servo, but it should be driving the average lateral acceleration to 
zero.

Original comment by Mr.Challinger@gmail.com on 7 Jun 2012 at 8:00