Octocopter - needed help in tuning

ArduCopter
1

So i was trying to tune my drone manually before autotuning. I did everything as the ( Initial Tuning Flight - copter ) page says ( Initial Tuning Flight — Copter documentation ). Actually i reduced these parameter twice by half :
ATC RAT PIT P/I/D
ATC RAT RLL P/I/D
.Unfortunantelly the drone after the first change started to drft and after second change it almost crashed due to wind and drifts it was doing then.

SO I RESTORED INITIAL PARAMETERS

Every record of the flights, and logs were done with the initial paremeters,.

IF U CAN TELL ME WHAT SHOULD I CHANGE OR WHAT SHOULD I DO NEXT I WILL BE SO MUCH THANKFULL.

Video- Quick Share
Logs- Flight - Google Drive

2

I would set these parameters and make another hover flight in Alt Hold to gather data for the Notch filter config:
INS_ACCEL_FILTER,10
INS_LOG_BAT_MASK,1
INS_LOG_BAT_OPT,4
PSC_ACCZ_I,0.4
PSC_ACCZ_P,0.2

These look high. Did you check with Motor Test? Setting Motor Ranges
MOT_SPIN_ARM,0.15
MOT_SPIN_MIN,0.24

1 Like
3

Hi … at first thanks for helping. I set these params : ( mot_spin… ) becouse i wanted to avoid crashes when lowering attitude in stabilize mode. And they are ok for me. ( if You think i should lower them for some reason according to the docs please tell me ) …

I will change the params u provided tommorow ( cuz its late now ).Thank You

4

You should follow the guidelines in the link I posted. MOT_SPIN_MIN is almost certainly too high. Set Arm to whatever you want below MIN.

1 Like
5

Here are the results … for me better and much more stable but i am posting these log and recording cuz maybe You can catch something, ofc if You have time to check. Againg thx for helping.

logs : Logs - Google Drive

video: Quick Share

Also i have a few questions … that drone is a prototype of something bigger… and it will be paired with soil sampling system which has 80cm and weights 3kg with also bigger and heavier battery (2,6kg ) and bigger motors for comparsion 3508 with 1555 prop into 5212 with 1861 which also weights 2kg more

( actual 1270 frame with motors weights 3kg with 600gr. batterry )…

Can i still try on that configuration with these parameters ( of course changing the prop size in initial tuning ) or should i do everythng again …

Also another question when i am for example autotuning the drone but without for example gimbal camera that weights like 1/2 or less of the drone`s actual weight should it be stable with the load on it…

Thanks for help.

6

You should use ecalc to work out the best components for your bigger copter.
The tuning process is the same, but you wont be able to just transfer the existing parameters to a bigger copter, there are too many differences.

You should tune and autotune without any payload, or at minimum take off weight. A gimbal would need to be removed. After tuning is completed you alter the ACCEL values to suit the payload via this formula:

new ATC_ACCEL_P_MAX = ATC_ACCEL_P_MAX x (min_TOW / max_TOW)
new ATC_ACCEL_R_MAX = ATC_ACCEL_R_MAX x (min_TOW / max_TOW)
new ATC_ACCEL_Y_MAX = ATC_ACCEL_Y_MAX x (min_TOW / max_TOW)

1 Like
7

am i right that min_tow is the weight in which the drone is doing an autotune and max_tow is the weight after putting the load?

8

Yes correct, Minimum Take Off Weight and Maximum Take Off Weight