Ground Steering offset issues

ArduPlane Plane 3.8
1

hello all, this is my first post. i’m not native English speaker so sorry for my bad English :grinning:

i have an issue with tuning ground steering in my plane volantex ranger ex 757-3. Even i followed the documentation of http://ardupilot.org/plane/docs/tuning-ground-steering-for-a-plane.html.

the issue happened while taxiing, when i hand off rudder to hold the current compass heading. the plane turns with about 180 degrees offset, sometimes after this process the plane start weaving.

pixhawk2.1 cube the autopilot that i use.
i use GPS here as the external compass

if someone had the same problem please help me or something that can helps me , i’ll appreciate that.

Best Regards,

2

maybe the ground steering servo direction is reversed?

3

thank you for answer, i tried this before with another UAV that has a separated steerable nose wheel, it worked properly , but no result with Ranger Ex that have a steerable wheel attached to rudder, even i add a servo Chanel on Mission Planner with GROUND STEERING function.