Heavy Lift Tuning Advice
Start with AUTOTUNE_AGGR at 0.08 and see what I get. I then move down in increments of 0.005 (so first step down is 0.075). If its too “tight” or oscillates I then go down and autotune again. If its too “sloppy” I go up.
Once I have it to my preferred “sharpness/crispness” I then set RC_FEEL_RP to between 70-80% and add in some expo (details on expo at end of post). It controls how aggressively the copter reacts to small changes in the stick inputs.
I was then working with ATC_ACCEL_RP_MAX and ATC_RATE_RP_MAX in 3.2, but these parameters seemed to have disappeared in 3.3. It seems these are the values left to tweak according to other posts:
ATC_ACCEL_R_MAX
Maximum acceleration in roll axis
Range: 0 180000
VALUE MEANING
0 Disabled
72000 Slow
108000 Medium
162000 Fast
Increment: 1000
It is not recommend going below 36000 and 54000 is a nice number for everyday relaxed flying. Most agile frames, running 10" props, are capable of 100000 to 120000 (on high powered micro quads this could easily double again).
and ATC_ACCEL_P_MAX
Maximum acceleration in pitch axis
Range: 0 180000
VALUE MEANING
0 Disabled
72000 Slow
108000 Medium
162000 Fast
Increment: 1000
These values should be similar to ATC_RATE_R_MAX
I read somewhere recently to decrease the following parameters by 10% after several autotune session and work up or down from there if needed on big copters: ATC_ACCEL_P_MAX, ATC_ACCEL_R_MAX, ATC_ACCEL_Y_MAX, RATE_PIT_I, RATE_PIT_P, RATE_RLL_I, and RATE_RLL_P
Here is what I am running for expo in the Taranis at the moment.
Aileron, Elevator, and Rudder Expo set by three position switch SG
40% for all in middle switch position
and 60% for all in up switch position
I mostly fly in the middle position (40%)