Problem?
The drone is not flying straight anymore. Sometimes it’s flying at an angle as much as 20-30 deg when trying to fly straight forward and then up to 90 deg left when braking, also giving some compass errors. I'm on holiday in the EU. Back in China the drone was flying fine. I did a new compass calibration when I arrived in EU.
I did 2 flights. The details below are from the second flight. I flew low and without significant wind. I have attached the .txt the .dat and a video of the flight showing the issue:
During the long run out it worked reasonable, then tuning back there was a slight offset:
104-597 sec
Then did some testing to get some clear examples to look at in the logs at:
760-785 sec
815-830 sec
848-860 sec
878-892 sec
905-915 sec
But it does not always happen for example:
1220-125 sec it works fine
Any ideas why this issue showed up and how to get it fixed? I can;t fly like this because it is not safe. I looked at the logs and clearly see the issue, but I have no idea how to fix it. Maybe someone can dive into the logs and come with a suggestion?
Was unit in a crash?
no, never.
What have you tried so far?
Re-did compass calibration in the middle of nowhere with phone 2m away on airplane mode. (Both IMU and compass interference are showing “excellent”.)
After 1st flight I moved several km to a new location for the 2nd flight.
Tried flying in different directions.
What device are you using ( iphone , ipad, Samsung , etc)?
iPhone 6S, IOS v11.3.1
What firmware are you running ( aircraft, remote controller)?
Aircraft: 01.04.0300
Remote: 01.04.0300
What Go app version are you using?
DJI Go 4: v4.2.12
Any modification?
None.
Did you change anything or install any apps?
Turned off the coordinate correction for use in mainland China.
Do you have a video or pictures of the problem? (if so post link)
Yes, .txt, .dat, DJI log viewer and video.
I would recalibrate the IMU's on a perfectly flat/level surface when the AC is cooled down to around 70-75°F. IMU's may be showing excellent signal but that does not necessarily mean they are calibrated properly. IMU calibration usually corrects drift.
It seems to have a fair bit of drift, the fact that you were flying low will mean that VPs will be activated, you need very good surface and light for VPs to work correctly, so a better test may have been above VPs limit.
However I’m not sure it would make a big difference, you should do IMU calibration, VPS calibration and gimbal calibration, then test above 30/40 ft out of range of VPS. You really need to preform a correct IMU as Quadkid has explained above.
hallmark007 Posted at 2018-5-21 03:20
It seems to have a fair bit of drift, the fact that you were flying low will mean that VPs will be activated, you need very good surface and light for VPs to work correctly, so a better test may have been above VPs limit.
However I’m not sure it would make a big difference, you should do IMU calibration, VPS calibration and gimbal calibration, then test above 30/40 ft out of range of VPS. You really need to preform a correct IMU as Quadkid has explained above.
Will do the IMU calibration and then another compass calibration and do another test flight as you suggested.
I have found a bunch of people reporting this issue without a clear fix.
I had a similar problem when I went on holiday to South Africa. Went away when I returned home (to the Northern hemisphere). I calibrated everything (IMU, compass, gimbal and RC) but nothing fixed it.
I just did an IMU update first thing after turning on the drone (i.e. as 'cold' as possible). now I have to wait for an opportunity to do some tests. I will report back.
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lvl.4
Second Officer
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