Servers by jDrones

Wobble in Windy condition (Loiter & RTL)

Hi Guys, I’ve just done my second flight from a new build TBS Clone with below specs:

Sunnysky x2212
9x5 Carbon props
4S Lipo
APM 2.6 with external GPS and Compass
200mw Video TX
Frsky V8FR-II Rx
https://www.facebook.com/photo.php?v=10152054465368264&l=8445007495268954207

I’ve 2 issues if anyone can give me some pointers.

  1. Low wind day. When taking off in stabilize mode, Copter always Yaw to the right about 90 degrees then maintains ?Yaw.(almost seems like it’s pointing to the north all the time. Trimming doesn’t help. In Loiter or Alt Hold this doesn’t happen Yaw stays. Video Link below. Ignore the RTL landing, a foam on the baro fixed that.
    https://www.youtube.com/watch?v=Tyehl8nHJVE

  2. Second flight - a little gusty about 20m up. Taking off in stabilized seems ok and then switch to loiter at about 20m. Every time it gets hit by some gust, copter starts to wobble. Check out the video below:
    https://www.youtube.com/watch?v=x8mTIY-Ckhk
    Almost throw up watching the video… look away if you have to :smiley:. It’ll be great if anyone can give me some advice to fix this other than installing a gimbal :slight_smile:

Thanks Guys!

Wobbling would be caused by tuning problems. Try autotune. Your log wrapped and overwrote the parameters so I can’t check your gains - do you have a log of a shorter flight?

I’ve not tried auto tune fearing it will fried my escs. I’ll try to do a shorter flight and upload it. Thanks.

Autotune can’t do anything that you can’t do in stabilize. If you have sync issues, it is so much better to know about them now. It won’t fry your ESCs, just reveal that they are problematic.

Thanks, jschall. Will give it a go. Cheers

I also have the same problem, while in Stabilized mode its very stable, but as soon as I hit loiter it wobbles to the point I have to return to stabilized in fear of a flip. with the telemetry I got a good 3d GPS signal feed back.
Setup:

390kv Motors
15x5.5 props
apm 2.6
30A afro OPTO ESC
5200 mah 6s lipo
Ublox Neo-7M GPS with Compass
telemetry set.

I think I have acceptable vibration levles.
[attachment=2]vibration.png[/attachment]

I dont want to do the autotune in fear of a desync due to the low kv motors.
[attachment=3]PID.png[/attachment]

I been juggling with the PID reading that the low kv motors should have lower P values in roll and pitch as in loiter P, this is not helping at all.

[attachment=1]vuelo 4.png[/attachment]

[attachment=0]vuelo 5.png[/attachment]

If You need any more logs pleas let me know

Thanks

Im running a heavy gunship of total take off weight 5.1kg. Its a quad on 330KV TMotors and autotune is also not an option due to desync possibility (I had it happen to me).

I had similar issues, excellent stability in stab and alt hold but wobble or relative quick correction on loiter mode. By manually tuning (map channel 6 to a pot) I changed Rate Loiter P to 0.720 (from 1.0) and also reduced Rate loiter I to 0.440 (from 0.500).

This resulted in a much more locked in loiter with far less aggressive correction when hit by wind or even just on windless days (since I had the wobble even on windless days).

Although I followed the instruction on how to manually tune, after saving the new settings and rebooting the quad, the I value now changed all by itself to 0.000. Seems like a bug in MP because I saw the same happen on a different occasion to the P value. So in both cases, I re-write those parameters in the full parameter list (because the extended window will not let me change it) and save them again. That keeps it then and shows up in the extended window too.

Hi everybody, had someone found a solution for this problem. I have the same
Pixhawk 2.8
Stable in stabilize and althold but wobbles in loiter mode and rtl. Could trim be the cause? Help please.

A problem that existed in 2015 may have no relevancy today. I suggest you create a new post with the problem you are having and include a link to a .bin flight log.

thx buddy for your advise

Servers by jDrones