@Mfoo wrote:
Dear fellow pilots.
I would like to ask for help on tuning my first Arduplane build, an 1.60m wingspan sea plane, running AP 4.1.0 beta4.
CG and control surface throw is within the vendor spec and it is flying good and stable in manual and acro.
In FBWA and cruise however, it oscillates on pitch and I could get rid of it.
Althogh the plane is about 2kg AUW and cant do a full loop, its quite sensitive on pitch axis.
I completed about 20 flights for tuning, changing CG, running autotune in different weather conditions or after lowering pitch P-Term manually but it never flew smoothly.
TECS have been tuned after the first successful flights and autotune.Autotune was done per axis until the message “* completed” popped up + an extra grace time after without stick input.
With higher P, there was less visual oszillation but a lot more servo oscillations or even active Dmod, as stated by the logs.
Comparing PIDFFs between the autotune results showed, that roll PIDFF values came out quite similiar but PTCH_RATE_P ended up between 0.05 and 0.95 across all attempts.
Here is the logfile of my last flight which shows:
- acro handsfree
- manual handsfree
- FWBA
- cruise
- some full-stick manual (I wanted observe the rates)
The concerning part is between 3m27s and 4m23s using the following PIDFF:
PTCH_RATE_D 0.002
PTCH_RATE_FF 0.158
PTCH_RATE_I 0.199
PTCH_RATE_IMAX 0.666
PTCH_RATE_P 0.06 (after cutting it down by half twice & testing)other (maybe useful) parameters:
SERVO_RATE 333 (digital servos)
SCHED_LOOP_RATE 100
PTCH_RATE_SMAX 150 (default)
AUTOTUNE_LEVEL 6 (default)I appreciate any input or idea. I cant fly the plane regulary so the more I can test, one by one of course, the better.
Thanks you all in advance,
cheers
mike
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