Gimbal calibration after repair, I am stuck, Mavic Mini but may apply to other models.

[Deleted member 103366]

I rebuilt a gimbal from a crashed mini, I put the camera in a 'new' gimbal frame and motors. The camera works and the gimbal does the boot dance, moving about all three axis (which is a plus) seemingly perfectly to my eyes but comes up with gimbal stuck message etc. etc. as was more or less expected.

There are several Youtubes addressing such problems

&

(this one seems to have the same problem that I detail below.)

showing gimbal recalibrations (or attempts lol) using python and some downloaded software
PYSerial: https://pypi.org/project/pyserial/#files
DJI Tools: https://github.com/o-gs/dji-firmware-

The software needs to know which comm port the drone is connected to and with either Windows 10 or 7 this is proving VERY difficult to nail down.
If I open DJI's Assistant 2 for Mavic and connect the drone, I see, in device manager, a consistant port, it's comm port 5 with one of the Windows but I don't remember if it is 5 with both. But as soon as I close the Assistant 2 the com port disappears from Device Manager.

Once the comm port is known and pyserial software is started "py setup.py install" using an administrator level command line you are supposed to issue two commands.

1) py comm_og_service_tool.py com5 WM160 GimbalCalib JointCoarse
(guessing com5 is the one I should use) "WM160" is the model number of the MM.
Followed by
2) py comm_og_service_tool.py com5 WM160 GimbalCalib LinearHall
( I have tried both com5 & COM5) .
I have never got past the first one as it crashes saying something about incorrect model or something similar and it presents a list which contains ........ , 'WM160' , ......

Noting the single apostrohies around WM160 in the error message I have tried including those in the command and I still have no luck.

One of the youtube comments led me to

DJI Spark Gimbal Calibration - Choice Technology Solutions, LLC

If you find yourself with a tilted or drifting horizon or basically a gimbal that just won't stay level on your DJI Spark this will be your fix.

nmbgeek.com

for a Spark, where one person used a Macbook.

I tried a Macbook and I see two USB 'ports' in use, one is consistanly something like /dev/tty.usbmodem2413 , the number of the other 'port' seems to change at random but this was more than I can see under Windows.

I have tried the
./comm_og_service_tool.py /dev/tty.usbmodem2413 WM160 GimbalCalib JointCoarse and the other port too but with no joy. Ditto 'WM160' and noting that the MAcbook user used SPARK rather than WM100 I tried the above with -vv MMINI as well as MMINI in place of WM160. No joy.

I am stuck. In part because I do not know if the commands are failing because they can not find the port and or the Model designation is somehow wrong.

Has any one succeeded with this. If so do you see anything wrong with my approach?
Thanks

 

[MA2 317]

I can't help, but THANK YOU for posting the information.

I have a Spark that has a gimbal problem after I repaired it myself.

Perhaps this information will help me, once I understand it.

.

 

[Deleted member 103366]

Good luck, hopefully you will see sensible comm ports etc..
If it works let us know what you use as the model designator for the Spark.
It's probably a lot easier for a hearing person to follow the videos than for me to relate the subtitles to what they are showing on screen.
DO NOT miss out any "." & "/" etc. in the commands.

 

[DoomMeister]

When you connect the MM via USB to your Windows PC is it recognized by the USB? If so, you may be able to find the port designation in Device Manager after it is connected.

 

[Deleted member 103366]

With no other programmes running an open device manager 'refreshes' as the drone is connected and disconnected but no comm port is visible on a permanent basis, I think that occasionally a comm port did flash up but quickly disappeared.
With Assistant 2 for Mavic running a comm port appears when the drone is connected and remains but as soon as the Assistant 2 for Mavic is shut down the comm port disappears.

 

[DoomMeister]

With no other programmes running an open device manager 'refreshes' as the drone is connected and disconnected but no comm port is visible on a permanent basis, I think that occasionally a comm port did flash up but quickly disappeared.
With Assistant 2 for Mavic running a comm port appears when the drone is connected and remains but as soon as the Assistant 2 for Mavic is shut down the comm port disappears.

With Assistant 2 running it creates a virtual Comm Port through the USB port. I have the same thing when I connect my golf GPS units to the PC as well as my Typhoon H using its GUI program.

When the connection appears in Device Manager note the designation it is assigned under Properties, Details tab. There are many different things found there. I am not sure if a Comm Port designation will appear there or not. Just an idea of where to check.

 

[Deleted member 103366]

I will have a look, thanks.

 

[Deleted member 103366]

A bit of progress I did as DoomMeister suggested and it's showing up as a virtual port, COM22. LEAVING the properties window open I shut down assistant 2 and tried the JointCoarse command, no joy but reading the error message I got the idea to stick " --port " in front of COM22 so the command reads
py comm_og_service_tool.py --port com22 WM160 GimbalCalib JointCoarse
That does something, the gimbal goes through all three ranges of pitch, roll and yaw but I get an error message. "Unrecognised response to calibration command JointCoarse request."
The LinearHall command just gives the error message.

EDIT the -vv thing, thats v & v with no space between the two v's, turns out to be a switch on for messages about what the command is doing.
But that doesn't get me any further along.

 

[Deleted member 103366]

I tried this on a working Mavic Mini.
I still get the "Unrecognised response to calibratio............." for both the JointCoarse and LInearHall commands but with the working Mavic Mini the "LinearHall" command produces a slow movement of the gimbal as opposed to nothing with the rebuilt gimbal.
So, it maybe that there is a fault in the bits that I used to rebuild the gimbal, ho hum.

 

[Joshlund26]

I am having the same issue with my Air 2S. I've tried two separate windows machines, both seem to give me a consistent COM port. Getting the same error message of "argument product: invalid choice: 'COM4'". Then it tells me to choose from a range of DJI model numbers (on of which is my drone).
It's almost like the it's trying to read the comport input as the model?

If anyone has made progress on this issue, I would greatly appreciate some input.

 

[DoomMeister]

@PhiliusFoggg

This thread may help you find the proper COM Port
Thread 'FIX Incompatible Gimball Error 40021 on Mavics (02-2020)'
FIX Incompatible Gimball Error 40021 on Mavics (02-2020)

I ran across it while responding to a post in the Approval Queue and remembered you were having issues with getting the right one.

 

[Deleted member 103366]

Thanks, I will have a look.

 

[WildWayne13]

Proper format of the string is
python comm_og_service_tool.py --port Com3 WM160 GimbalCalib JointCoarse

Unfortunately I think the newer firmware versions don't support JointCoarse. At least the Mini 2 doesn't appear to.

Anyone know how to remove the...

Incompatible Gimble Data

from a Mini 2?
Every thing is working correctly other than it has the error message.

 

[BBZeus420]

Proper format of the string is
python comm_og_service_tool.py --port Com3 WM160 GimbalCalib JointCoarse

Unfortunately I think the newer firmware versions don't support JointCoarse. At least the Mini 2 doesn't appear to.

Anyone know how to remove the...

Incompatible Gimble Data

from a Mini 2?
Every thing is working correctly other than it has the error message.

Have you found a solution to this?

 

[WildWayne13]

Have you found a solution to this?

No, I'm stuck with "gimble calibration error", but only at the drone startup self calibration. The auto calibration completes successfully every time. Then after you click on the x to return to DJI main window the drone resets and runs it's own calibration attempt and gives the error. Everything is working correctly including the gimble, just stuck with a bogus error message. I have this on three different repaired drones. I tried to get DJI tech's to verify the need for a software/firmware serialization reset, but they continue to play dumb and won't verify or deny. It's ashame the after market community can't get access to the needed tools to fix these problems. A 5 minute $30 dollar fix is turned into a several hundred dollar 2 week fix. I guess it time to stop supporting DJI and move on to a brand that doesn't mind a robust after market community.