Px4 setup for B-2 bomber

PX4 Autopilot Flight Controllers đź’»
1

Hi all
I am building the B-2bomber per Chris Golds plans. Is it possible to set up the drag rudder when setting up a flying wing?
Michael

2

@B2bomber Exciting project! Yes, you can set up the mixer in order to use split elevons to create yaw torque. What you would have to do is to feed correctly the yaw control output into each control surface in the correct direction.
A few hints to avoid mistakes:

  • Make sure the negative gain is zero on one side and the positive gain is zero on the other side since you can’t create negative drag.
  • I would recommend to set the outboard elevon down and the inner one up in order to increase the total yaw torque
  • Adjust inner and outer deflections gains in order to minimize roll torque during yaw actuation (depends of the ailerons surfaces and distance to the CG).
  • Saturate the contribution of yaw in the mixer to ~30% of the total elevon motion to avoid degrading roll and pitch control

Do you have three elevons on each side like in the real one? Would you like to use all of them together for roll/pitch/yaw?

3

Thanks for the hints. Yes the plans show 4 Inger control surfaces and the 2 “drag rudders” at the wing tips. I am just about to start the project and is still in the research phase.

4

@B2bomber Oh, okay, I thought that the drag rudder was a simple elevon that would need to be mixed properly with the two inner ones to compensate for the roll/pitch torque that it would generate.

Forget about what I said in the previous post, it’s much simpler with those drag rudders, it’ll be straightforward to use them with PX4 :wink: Tell me when you have the airframe done and if you would need help to set up the mixer properly.