[size=14.6667px]So my NAZA (v2) is doing a strange thing and hoping someone out there might have an idea or have experienced this issue also. It is custom build, multiwiicoptor.com scarab reconn 600 frame, tiger motors, 20a blheli escIt's not my first build and everything else is fine, just having problems with the following and if anyone can help at all it would be HUGELY appreciated.

[size=14.6667px]It's windy here most the time so have never noticed before, but I was doing a real estate video yesterday (I don't use a gimbal so it shows up in the video) when it was very still and I noticed that the airframe rocks from front left to rear right and back, about 1-2 rocks per second... only moving a few degrees.

[size=14.6667px]I know it's the FC (or the fc dealing with something) as if I run it in manual mode I get no problem.

[size=14.6667px]I just leveled the airframe and FC then did an advanced calibration, still the same.

[size=14.6667px]The arms are exactly the same length within a fraction of a mm.

[size=14.6667px]I had the motors pointing in their yaw direction a few degrees, then also tried leveling them off again, still the same.

[size=14.6667px]Frame is well balanced, makes no difference if I offset the balance a little or not.

[size=14.6667px]Does it in atti. and gps mode but not in manual mode.

[size=14.6667px]It is isolated from vibrations on PU gel balls... props very well balanced (zero jello videos) triblad props.


[size=14.6667px]My NAZA has always had little niggling problems that come and go - it has been reliable to an extent (almost lost it in strong wind the other day when it was fine the previous strong wind flight).... do flight controllers age?

[size=14.6667px]I have an iNav Sirius air 3 with m8n gps board and a multiwii + gps..... should I just change FC? What is considered a good FC these days. I just want rock solid locked in feeling with solid gps lock as backup. I'm suspicious the NAZA creates tiny little oscillations that creates shaking in the video, regardless of tune, that you don;t see in videos from well tuned multiwii boards.

[size=14.6667px]Thanks!

Just so that I'm on the same page, it's not rotating in a toilet bowl effect, but swaying in a "t or x" like fashion? Have you tried adjusting the gains?

gday thanks for the response.

no rotating or toilet bowl.

it is swaying in a "\" pattern, so it dips to the front left and then back to the rear right... repeating that movement. it's hard to notice at first but you can hear the motors going "hum hum hum hum" and in the video you can see it looks like it just rocks back and forth (left to right and back) just a few degrees, but it ruins the video (as I don't use a gimbal).

it still flies very stable and doesn't do it in manual mode, it will still do it when you;re flying around at the same rythm. adjusting the gains will just change the rythm, so if you turn the gain way up it will just do it faster... so setting the gain to a point where it's oscillating rapidly it will still do it, about 1 rocking motion per second instead of about 1.5 rocks per second. basically it appears to be independent of gain.

I have tried:
changing the angle of the motors
changing the balance of the craft
advanced calibration
checking for magnetic interference
balancing the props even better



ESC issue was one of my thoughts but it should still do it in manual mode of that's the case.... what calculates "level" in the NAZA? perhaps theres something wrong with the levelling system

well I somewhat fixed the problem to my surprise
I made it significantly rear heavy and it stopped doing it
it's rear heavy enough that i can visibly see the frame leaning back in a hover yet it stays in place and also yaws smoother than before.
it's a symmetrical x frame with a very obvious center point and the NAZA unit is mounted directly in the middle... yet moving the battery more towards the rear so that it would lean back when I lifted it from its center point yielded desired results.... I just, don't even understand >.<

fans63520f27 Posted at 2017-6-28 22:19
well I somewhat fixed the problem to my surprise
I made it significantly rear heavy and it stopped doing it
it's rear heavy enough that i can visibly see the frame leaning back in a hover yet it stays in place and also yaws smoother than before.

Good to hear you've made some progress. Have you also checked your X,Y and Z values in the GPS mounting just to further troubleshoot it?

I did double check that, it was actually out by 1cm along the x axis if I measure exactly center of gravity to center of gps unit. I have also been measuring from center of main unit to center of gps not gps to cog... cog on my quad is much lower than a originally realised too...
I will do a test flight today.

So in the assistant software there is a pop up description in the mounting section that I never noticed before. It says that if you don;t put in the x y z mounting measurements exactly, the multirotor will oscillate.
My x measurement was out by 1cm.... just 1cm. I corrected it.

Now it flies perfect, huge difference by just changing the mounting by 1cm.