Elevon plane FBWA pitch inversed

Hello all,
I’m running a flying wing with 2 elevons as it’s only control surfaces.
When I control the elevons in manual mode through my transmitter, the pitch and roll work perfectly
When I put it into FBWA mode, it stabilizes the roll, but stabalizes inversly on the pitch. (for example if plane is pitched down, the elevons pitch it down more.
Also the ksp-style 3d direction thing displays the correct pitch, so the drone does know the actual pitch.

Here’s what i’ve tried:
1.Finding a config or check box to reverse the pitch of elevons. I did find FBWB_ELEV_REV config, but it didnt seem to change anything I assume because its FBWB and ELEV means elevator not elevon.
2.Inversing pitch for the elevons, and then re-inversing the pitch from my transmitter. I can’t seem to find a way to just change the pitch on elevons (without also affecting the other functions of elevons such as roll)

Thanks in advance.

This will help you: Elevon Planes — Plane documentation

Rolf

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Yes ive read it. Like I said though, I can’t seem to find a way to change just the pitch on elevons.

This might be a bit of a silly question, but when you are connected to mission planner, does the tilting the aircraft nose up show on mission planner as the aircraft being nose up? If not, it might be worth recalibrating your IMU.

Also, I think it is possible to end up in a situation where your servos are both reversed (left/right) and inverted such that manual control will come through, but AUTO modes will not work correctly (I ended up with something like this while setting a wing up a while ago).

I hope that helps diagnose your problem.

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@ChapEng may have nailed it, but I want to add:

When configuring servo direction, simply using manual mode to eyeball the results is usually a terrible idea. And it’s often even worse to start reversing RC channels (vs servo outputs) when results don’t expectation. Use FBWA on the bench to ensure the autopilot responds properly. And if it gets too confusing, go back to basics and make sure calibration and orientation are performed properly.

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You need both: First you need to control the direction of the deflection with FBWA, then you need the manual mode to set the servo limits (min/max and trim) for each control surface.

Rolf

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