Drone Drift

1

Hi!

I have this issue with almost all my drones, they are not very steady on loiter mode. Always is movig, not too much, but for my 30X zoom camera is very anoying.

How can I fix that drift? is a GPS problem?, PID? COmpass? all toghether?

I apreciatte your comments.

thanks!

2

This is what tuning and correct setup and calibration is all about.

  1. Frame - is the frame rigid enough? Are the motors ABSOLUTELY level? Has the FC adequate vibration damping? Any other frame variables?

  2. Calibration - Have you done ALL the calibrations? Compass Motor calibration? External compass? low or high offsets? ESC calibration? Is the FC level? Have you calibrated level? How many Autotunes have you done?

  3. Flight - Adequate power - batteries, motors/props, power to FC (yes, that can have an effect)?

As you can see there are a lot of variables, and I haven’t touched all of them.
Presenting a flight log of a typical flight would allow a much more precise analysis of what is happening

3 Likes
3

HI!

Thanks! About your questions:

  1. Frame - is the frame rigid enough?
    Yes
    Are the motors ABSOLUTELY level?
    The most I could do
    Has the FC adequate vibration damping?
    It suppose the PixCube has internal vibration damping, so no external damping
    Any other frame variables?
    Emmmm, nop
  2. Calibration - Have you done ALL the calibrations?
    Compass Motor calibration?
    Yes
    External compass?
    Yes
    low or high offsets?
    Can you explain what offsent do you mean?

ESC calibration?
Yes

Is the FC level?
Yes

Have you calibrated level?
Yes

How many Autotunes have you done?
1 and manual tuning

  1. Flight - Adequate power - batteries, motors/props, power to FC (yes, that can have an effect)?
    Each motor can draw 16Amp máx, 6 motors, 96Amps max plus the electronics, 6S 20Amps an 10C discharge battery. Mauch electronics to power up the FC

Attached is one of the logs.
http://robomotic.dyndns.org:16211/archivos/logs/logHexaPixCube.zip

I apreciatte your help.

Thanks

4

If you have a look at Desired/Actual in ATT you can see your tune is quite busy.
From your specs you must be running at least 15" props, but your ATC_RATE filters are still at the default 20.

Have you read the Wiki pages on tuning and autotuning?

1 Like
5

Thanks for your help. I have readed a lot of tuning, videos, etc, but always is welcome more information about that. If you can recomend me a Wiki about tuning or more info about it ill be great!!

thanks!

6

…ok, I was checking the ATT and as you have told me , the pitch an d the rolls were a quite busy. The Yaw was ok!

CAn you give me a hand with the ATC_RATE, its a pareameter I never had change. I look them in the parameter list and i have found ATC_RATE for the P, R and Y, but I really dont know what they mean.

About the props,you are right, im using 15x55 props, but I cant find how the ATC_RATE are related with the props, or may be I didn´t understood very well.

I will apreciatee if you can explain me pls

thanks!

7

This is the Tuning start page in the Wiki
http://ardupilot.org/copter/docs/common-tuning.html

From the Autotune page

  1. For large copters (with props at least 13inch or 33cm diameter) set the Rate Roll and Pitch filters to 10hz (in Copter-3.3 these are RATE_RLL_FILT_HZ and RATE_PIT_FILT_HZ, in Copter-3.4 they are ATC_RAT_RLL_FILT, ATC_RAT_PIT_FILT)
1 Like
8

Thanks! I will read it right now!