Why is my drone shaking so much (with logs)

ArduCopter Copter 4.0
1

Hi, I would like to ask for help analyzing why my drone is shaking so much. I wonder if it’s just a “balance weight” issue or something else

Here is the log file

And a screenshot with logAnalyzer + filter by “ERR” messages type:

image
image1327×788 119 KB

The last ERR msg reporting a CRASH is related to another issue (in fact the drone landed very well before).

I’ve seen that compass complains about mag, I’ve got two of them configured:

  • Primary: AK09916
  • Secondary: the internal inside the pixhawk 4 mini

As you can see in the following pics, I’ve mounted the external gps far from ESC, so why I still have mag issues ? is it’s related to the shaking issue ?

IMG_8896
IMG_88961920×1440 276 KB

IMG_8897
IMG_88971920×1440 252 KB

IMG_8895
IMG_88951920×1440 239 KB

IMG_8898
IMG_88981920×2560 368 KB

IMG_8849
IMG_88491502×1333 191 KB

I can add more details if required !

2

LiIon on top of pixhawk? They tend to generate some mag fields.

I would start from disabling internal pixhawk compass.
PS - did not take a look into logs, but had similar issues with own build.

And… do some cable management - keep wires between power hungry parts as short as possible. Making a coil from motor wires for sure does not help :wink:

3

Thanks for the help !
Yep, it’s li-ion. Better using lipo to avoid mag fields ?

EDIT: also I’ve noticed that the “dampers” (under the pixhawk mounting) are not made of rubber but are plain plastic as presented on the holybro commercial picture

image
image1080×1080 57.7 KB

4

I think your FC already has internal dampening. Possibly try hard mounting with two sided tape.

5

You are on old firmware and using default parameters. And this is the result of using default parameters for that craft.

RCout
RCout1694×502 140 KB

Massive output oscillation. Note that this has nothing to do with levels of vibration which are not high.

Update to latest Stable version and at your level of knowledge work thru the Methodic Configurator. Use search here on the forum to find it.

BTW-The Auto Analysis Tool is useless. It is way out of date.

1 Like
6

Thanks for your advise here !
So it’s a software issue ?

I’m kind of stuck on the firmware version, because it’s skybrush firmware… I guess I could migrate to a pixhawk 2.4.8 because it seems more stable by default…

Can I still use methodic configurator and get better results ?

Also, can you explain me how you find this oscillation graph, ideally from my .bin file ? and how It should looks like to get cleared of the oscillation ?

EDIT: I’ve just started reading the hardware to avoid pixhawk 2.4.8 :rofl:

7

It’s a PH4-Mini right? Just use Mission Planner and update it to latest Stable. Then start with the Configurator.

The filed to graph are shown in what I posted. RCOUT. It should something like this at hover not oscillating between Min/max output:

RCout good
RCout good1692×516 107 KB

8

Yes it’s pixhawk 4 mini with a special firmware named skybrush firmware, derivated from arducopter

My guess is that I can’t update it through MP because I’ll loose skybrush specific features… no ?

I’ve been thought the methodic configurator and the associated documentation…
I’ve missed a lot during assembly !

Thanks and good luck with this awesome project

1 Like
9

Maybe, or it could just be the V4.4.0 Stable version from AUG23. I can’t tell from the hash, someone probably could.
What is the latest version from Skybrush?

10

from skybrush doc: Current version: 20230920

11

I loaded the Development version on a CubeOrange+ and it’s V4.5.7 which is current Stable Arducopter. So I would load that.
This version has Arducopter default parameters and that craft will not fly on defaults as you have already discovered.

12

Thank you for your help here, even further than normal arducopter scope.

My understanding is that I have missed a lot of documentation (arducopter wiki + methodic configurator README) and tools (Methodic configurator).

I’ve also found “webtools” which looks great to identify issues or not (for instance, it looks like my mag0 is fine)

I’ll do better for the next time.

Thanks again

13

You were right about their being specific parameters from the Skybrush version. Comparing it to Stable version Arducopter there are these that I have never seen before clearly for their specific functionality:
CM_FLOCK_OPTIONS,0
SHOW_CTRL_MODE,1
SHOW_CTRL_RATE,10
SHOW_GROUP,0
SHOW_HFENCE_DIST,25
SHOW_HFENCE_EN,0
SHOW_HFENCE_TO,5
SHOW_LED0_CHAN,0
SHOW_LED0_COUNT,16
SHOW_LED0_GAMMA,1
SHOW_LED0_TYPE,0
SHOW_LED0_WTEMP,0
SHOW_MAX_XY_ERR,3
SHOW_MAX_Z_ERR,3
SHOW_MODE_BOOT,2
SHOW_ORIENTATION,-1
SHOW_ORIGIN_AMSL,-10000000
SHOW_ORIGIN_LAT,0
SHOW_ORIGIN_LNG,0
SHOW_PRE_LIGHTS,2
SHOW_START_AUTH,0
SHOW_START_TIME,-1
SHOW_SYNC_MODE,1
SHOW_TAKEOFF_ALT,2.5
SHOW_TAKEOFF_ERR,3
SHOW_VEL_FF_GAIN,1

But it seems to me that you can follow standard Arducopter tuning methods anyway.

1 Like
14

Yes, I’ve dealed with some of them already in my hurry of doing things too fast :rofl: