Thanks to helping minds in advance.
I’ m building an agri drone with the following specs
T motor p80 120 kV motor with 29 inch props
Flame 80A HV esc
12s 16Ah battery ( for initial testing )
Symmetry X frame
Cube orange flight controller
Arducopter 4.3.1 stable as autopilot firmware
I tried the following tests,
Tried flying in stabilize with the default params, vehicle found to be oscillating.
Mot_thst_expo interpolated from the graph available on the documentation and found as 0.8 for 29 inch props
Changed pid values to half along with couple of other params including filter values etc.
After that vehicle seems to be flying good.
Tried alt hold , vehicle started wobbling oscillating up and down ,
Changed POSZ params by half and problem solved.
Enabled harmonic notch ( set it to mode 4 )
Tried to do autotune in roll, failing with a GCS message autotune failing to level
Tried to do autotune on pitch axis, same error
After some readings, reduced the autotune_aggr to 0.075 and tried the same no positive results. Still getting the same error,
According to documentation did manual tuning for d term and pi terms , ended up in reduced pi values and slightly increased d value from previous pids,
After Manual tuning pushed for auto tune, still failed due to same level issue.
After all this tried some basic pos hold, RTL, auto flight modes and the vehicle behaved well.
Now can anyone suggest me why I’m failing at auto tune?
Do I really need to do autotune ?
Because after all this I tried dumping some 15kg payload to the vehicle , it failed to take off in pos hold and started high amplitude oscillations .
It would be helpful if someone can suggest any mods or tweaks to be done to get it work/ tuned better.