As you can see in attached pic, my Log data sometimes indicates YAW momentarily diverging away from desired YAW input. Has anyone else seen similar data? I mostly see this when YAW input angle are significant. I've also attached my tlog & bin files, if someone as time to quickly look at my YAW data.
(APM 2.6 H-Copter, all up weight 1.5 Kg with APC 12x4.5 and 3 cell 3300mAh)
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When yaw can't track des yaw is commonly a hardware issue, check carefully if you can find the problem, perhaps the frame is too flex?, It's the first time that you see? one test that you can do is to put your mobius behind the copter where you can see the copter attitude during flight, if forward arm flex sometimes, I saw that test done by Roberto Giordano in a similar design, and discover that, if I find the post I share it.
Thanks Cala for taking the time to respond, much appreciated. After going over the logs in detail and utilizing the Mission Planner's tuning screen while re-playing the telemetry log to have a better visual perspective as to what was occurring in regards to the YAW, I've come to the conclusion that YAW in reality was not momentarily swinging away in the opposite direction. I was wrongly interpreting the graphs; in the above pic that I posted earlier you can see that the heading was 30 and then the mission requested a heading change to 260 degrees; the quad carried out an anticlockwise turn (left) thus the numerical degrees decremented from 30 towards zero and passing 360 and eventually arriving at 260. I am assuming that this quirk in the visual data must be occurring every time a transition occurs thru 0/360.
Anyways, when we get clear weather I will try to reduce the apparent lag in the YAW input which is sometimes 1.5 seconds.
Can you share a photo from your copter?, It's possible that you have a motor twisted?
As requested here is a pic. I built it from scratch approximately three years ago and it has close to a hundred or so flights. Trying to fine tune YAW and Throttle Accel PIDs. Here is a link to a video taken from an on-board Mobius camera.