Hi folks,
I built a small copter (TOW 1,2kg) with a KakuteH7 v1.3 that does fly very nicely in Stabilize mode, but is audibly “pumping” in AltHold or Loiter mode. But it does hold the altitude.
That oscillation occurs always, no matter of ground effect or >10m high.
I tried to tweak the Alti Hold parameters in Extended Tuning in Missionplanner to now avail. Do you have an idea to solve that?
My configuration:
X quad
9x4 props
T-Motor F90 1300kv motors
M100-5883 GPS/compass module
Graupner GR-12 HoTT as receiver Kakute H7.param (20.7 KB) 00000015.ZIP (507.7 KB)
See parameter file and log a file of a short flight close to ground (in AltHold flight mode).
Compass and sensors are calibrated of course.
It’s difficult to determine what the Hover Thrust value is but suffice it to say it’s a lot lower than .125 which is the lowest that will be learned. Let’s guess that it’s ~.06 so set these:
PSC_ACCZ_I,0.12
PSC_ACCZ_P,0.06
When you have a THo that isn’t oscillating you can re-set these and MOT_THST_HOVER (and disable learning)
You will have to revisit the tune and perhaps lower the pitch PID’s.
Did you set the motor ranges as per this procedure? Set Motor Ranges
Because MOT_SPIN_MIN is very high which you can see in the RCout graph.
Also I would use Dshot600 and you need to configure the Notch Filter.
Out of curiosity what ESC’s are you using and what firmware do they run?
Set these so we can look at the data for the Notch filter:
INS_LOG_BAT_MASK,1
INS_LOG_BAT_OPT,4
Hi Dave,
MOT_THST_HOVER was at 0.125
I did set the values of PSC_ACCZ_I to 0.24
PSC_ACCZ_P to 0.12
and switched to DShot 600
and the oscillations are gone!
The altitude is held as steady as I would like it, so that needs some more work from there.
Motor range needs to be set too.
The ESC used is a “4in1” Tekko AM32 60A.
Anyways, thank you very much for pushing me in the right direction!
