I purchased a P4Pro two weeks ago (my fourth DJI UAV), updated all firmware, made sure all stickers and foam shipping insert were removed from gimbal, performed a very careful cold IMU calibration per my established practice on a perfectly level mable countertop in my kitchen, and then calibrated the gimbal (twice) using the same level marble countertop. I then tested the gimbal calibration at home by power cycling the P4Pro with no props attached, picking up the P4Pro in my hands and observed live video on my iPad Air 2 while moving it left, right, forward, backwards, tilted it left up to 45 degrees, tilted it right up to 45 degrees, moved it forward and backwards while tilted - and the gimbal remained perfectly level through all these non-flight tests!  Excellent - now time for real flight testing in the field.

All the following flight testing of P4Pro was performed in P mode with 16+ GPS satellites locked in and with Obstacle Avoidance turned ON. HD flight mode was set to CUSTOM, 2.4 GHz, Channel 19, at lowest video transmission rate (slider all the way to the left).

I powered up the P4Pro, calibrated the compass, adjusted the focus point, started the video recording and noted the following repeatable issues with regard to gimbal horizon:
1) Horizon was perfectly level while hovering, rotating while hovering, and moving less than 10-15 mph forward or backward. EXCELLENT!
2) Horizon tilted 5-15 degrees (high point on left of screen, low point on right of screen) as forward speed increased above 15 mph and got progressively worse as speed increased up to 36 mph. Magnitude of tilt appeared directly related to speed of aircraft. I stopped aircraft 4 times, and horizon leveled out every time to within a 1 degree of perfectly horizontal - sometimes this took 5-10 seconds, twice it took over 45 seconds to return to level. This tilted horizon while flying left is DISAPPOINTING and UNACCEPTABLE.
3) When flying to the left, the horizon tilted severely to the left (high point on right side of screen, low point on left side of screen) approx. 15-25 degrees. After stopping and returning to stationary hover, gimbal horizon returned to level after 20 seconds. The tilted gimbal horizon when flying left was VERY DISAPPOINTING and UNACCEPTABLE.
4) When flying backwards at various speeds up to 34 mph, the gimbal horizon remained perfectly level. This was SURPRISING (considering amount of tilt when flying forwards), but welcome and definitely VERY ACCEPTABLE.
5) When flying to the right at various speeds up to 34 mph, the gimbal horizon tilted to the right about 5 degrees. With aircraft at stationary hover, gimbal horizon returned to level after about 20 seconds.
6) On an extended long-distance flight over unpopulated and very flat farmland and grazing land at a constant seed of 34-38 mph, the gimbal horizon was again tilted 15-20 degrees to the right. I was able to use the gimbal adjustment while maintaining forward speed and acheived a stable, level gimbal horizon at a gimbal adjustment of 3.1, which is HUGE adjustment.  However, any time I slowed down or stopped, the gimbal would tilt the other direction and I would have to reduce gimbal adjustment to zero to get a level horizon while in stationary hover.
7) On return flight of 20,000 feet (in opposite direction, of course), I once again had to apply about a 2.9-3.2 gimbal adjustment to achieve a stable, level gimbal horizon at a constant speed of 34-36 mph. But, as before, the gimbal horizon would tilt the opposite direction whenever I slowed down, and when I stopped I would again have to set the gimbal adjustment back to zero to get a level horizon.

This tilting gimbal horizon (after careful IMU calibration and gimbal calibration on level marble surface) when in forward flight, flying left and flying right is UNACCEPTABLE and cannot be easily compensated by adjusting gimbal BECAUSE the magnitude of the horizon tilt and the amount of gimbal adjustment required is a function of P4Pro horizontal speed (i.e., a single adjustment setting will not produce a level gimbal horizon at all horizontal velocities, which is an unworkable situation).

Since P4Pro is perfectly level when in a stationary hover, when turning 360 degrees, and when flying backwards, this variable tilting of the gimbal horizon proportional to horizontal speed when flying forwards or sideways appears to be a bug in the software controlling flight and gimbal positioning rather than an IMU or gimbal calibration issue.

I am hopeful a firmware update is forthcoming that will address this issue. If not, I will have to return my P4Pro to Best Buy for a refund before my 30-day exchange period expires and then repurchase another one when this forum indicates this gimbal horizon issue has been resolved by new firmware.

What are other P4Pro owners experiencing with regard to gimbal tilt as a function of horzontal velocity during forward and sideways flight?  Does your calibrated gimbal horizon surprisingly remain level during reverse flight like mine did? Please provide your testing results in this thread as the more information we can provide DJI, the quicker they may be able to diagnose and resolve this bug.

I don't recall seeing this issue being raised here as a recurring problem, I suspect it is just happening on your aircraft. In any event, take it back to Best Buy and ask for an exchange.

Yes, this is a new condition, not mentioned previously, that I know of. ;-)


RedHotPoker

Aloha Mann,

     Did you go into the General Settings and look into the Gimbal option?  Was the Gimbal set to FPV or Follow.  If the gimbal is set to FPV, it explains your problem.  Set it to Follow and try again.  Your angles are rather extreme, but other settings and wind could contribute to the problem.

     I hope this simple solution solves your problem.  We can always hope!

Aloha and Drone On!

After doing some searching on this issue, I found Bill Nichols of BillNicholsTV reporting this same issue with regard to gimbal tilting of his first P4Pro+ at high speed when flying forwards and backwards. He first says this was happening when flying backwards - started out level but would tilt more and more as he increased speed going backwards - but then says he experienced gimbal tilt when flying forwards also at speed. He indicated that gimbal calibration and IMU calibration did not fix this issue and that 8 other people had reported to him that they had a similar problem.  He returned that P4Pro+.  

His comments on this can be found in the following YouTube video between 3:15 and 3:55


So, apparently this is an issue with at least some P4Pro and P4Pro+ devices.

Note: the bulk of this video is on his struggles to sign in on the tablet, register and upgrade the firmware on his second (replacement) P4Pro+.

Cetacean Posted at 2017-1-24 01:29
Aloha Mann,

     Did you go into the General Settings and look into the Gimbal option?  Was the Gimbal set to FPV or Follow.  If the gimbal is set to FPV, it explains your problem.  Set it to Follow and try again.  Your angles are rather extreme, but other settings and wind could contribute to the problem.

Cetacean,

Thanks for the tip, but under Gimbal Settings, Gimbal Mode was/is set to "Follow".  

Same issue here. On Follow, the gimbal keeps tilting right and left depending on the speed of the UAV. It is so bad I though I was in FPV mode but unfortunately not.

TheMann58 Posted at 2017-1-24 18:50
Cetacean,

Thanks for the tip, but under Gimbal Settings, Gimbal Mode was/is set to "Follow".

Aloha Mann,

     Well, I was hoping!

Aloha and Drone On!

RedHotPoker Posted at 2017-1-23 23:42
Yes, this is a new condition, not mentioned previously, that I know of. ;-)

RedHotPoker,

After IMU and gimbal calibration, is your P4Pro maintaining level horizon at higher speeds flying forwards, backwards and sideways?

fans7d4c3e61 Posted at 2017-1-24 21:52
Same issue here. On Follow, the gimbal keeps tilting right and left depending on the speed of the UAV. It is so bad I though I was in FPV mode but unfortunately not.

Well, at least I'm not the only one with this variable P4Pro gimbal tilting issue when flying faster then 12 mph forwards or sideways.  

I took my older P4 up immediately after my extended test flights with the P4Pro and did not experience anything but very minor gimbal tilt issues flying the same speeds, wind conditions and flight path.  I am confident that DJI will get this sorted out, but it might take a couple of firmware updates to get everything tuned in and rock stable.  That was my experience with the P4, which is my workhorse right now.

TheMann58 Posted at 2017-1-25 12:30
RedHotPoker,

After IMU and gimbal calibration, is your P4Pro maintaining level horizon at higher speeds flying forwards, backwards and sideways?

As I only have a Phantom 3 Pro, I can't comment on your P4Pro question.
But I have a question, Under camera controls, do you have your gimbal set for Follow or FPV?
Sounds like you have FPV setting...

RedHotPoker

RedHotPoker Posted at 2017-1-25 13:19
As I only have a Phantom 3 Pro, I can't comment on your P4Pro question.
But I have a question, Under camera controls, do you have your gimbal set for Follow or FPV?
Sounds like you have FPV setting...

Gimbal was definitely set to "Follow".

TheMann58 Posted at 2017-1-26 05:38
Gimbal was definitely set to "Follow".

Ok, well it was a shot in the dark, but something worth checking on.... I'm Not sure how else this can be corrected.


RedHotPoker

I have exactly the same issue, the gimbal drifts when I move sideway and come back straight after 10-20 sec (and from what I see on Youtube, a lot of people have the same issue but don't even know that it's not normal). After an IMU calibration (and then an other gimbal calibration), it's better but not as good as my P3P is. I would say, it has gone from 10-15° before the calibration to around 5-6° drift after the calibration.

I have a P3A and I seem to be experiencing gimbal tilt which may be varying.   Noticed it when flying high and the horizon didn't seem straight.   I made gimbal roll adjustments but can't remember when in my adventure today I made the adjustment.   Yesterday I though I noticed some tilt but checked my videos and didn't seem as bad as today.
I did run an IMU calibration last night after letting the AC sit outside in about 50 degree weather in hopes I could shorten the warmup time.   Perhaps that is a factor.
I did run a gimbal calibration when I got back today.   As it is doing the calibration it seems straight but when it completes, it seems tilted.   I made about a -0.7 adjustment.   We'll see on my next flight if the level is better.   I should have the motor that's knocking a bit replaced by next weekend too.

Same issue here. Permanent drift of horizon, way worse than I ever experience on my P4, inspire or P3P. And gimbal tilt when the shutter trigger in picture mode. I am sure it will be fixed but please can someone look at it? New sensor is awesome though!

This is an interesting post,  I posted the same issues on Youtube and people assume you dont know what you are talking about. I can relate to the very issue you are experiencing.