P4P 2.0 slow drifting in hover

Do we know if the P4P v2 has 2 IMUs? They only put one IMU in the Mavic Pro.

Well I sure hope so because if they did not there will be a bunch of ticked off people. The manual claims it has a dual IMU.

I can't imagine them putting a dual one in the Mavic Air and a single in the P4P 2.0.

I guess anything is possible though. They have changed some significant stuff before and not been up front about it.

dual.png


There are also two sets of gyros, accelerometers, and compasses that show up on the sensor status page.
 
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@BudWalker & @sar104 ,

I went back and studied the DAT files of the 1st two P4P 2.0 drones that I tried (different issue made me exchange them both) and they both also display similar characteristics to this 3rd one that we have been discussing in this thread. I never noticed the slow yawing on those in hover because I was focused on the other more obvious issues with those 2 and never was worried about the fine details of their performance but after looking at the logs, they were also doing the same thing.

Either there is something to the USA DJI Support guy's claim that this is a known bug or DJI has some horrible quality control on these things with 3 out of 3 having issues out of the box.

Thank you both for your help you provide the community!
@BudWalker thank you so much for your log analysis tools!
 
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@BudWalker or other wizards of drone logs,

I was wondering if you could take a quick look at the following and tell me why my new P4P 2.0 is slowly drifting in hover. Depending on which way I turn leading into the hover, it will start to slowly rotate on its own and may go clockwise or may go counterclockwise. It will also eventually stop turning if I let it sit long enough. I made sure to be in a large field away from anything for this flight.

Looking at the logs with my limited knowledge I see that the yaw and mag-yaw are sometimes drifting apart or back together which seems to correspond to what I am seeing.

I found a similar issue with the Mavic Air that DJI claims will be fixed with firmware soon. Is it possible that the new P4P 2.0 is using similar code or hardware that makes it have this same issue?

2018-06-16_08-41-35_FLY008.DAT
Callibration needed
 
I have the exact same problem with my P4P+ 2.0 as the OP. I did my first shoot with it on a night shoot last evening and the drone constantly drifted and rotated in hover mode. It made taking long exposures for stills impossible.

And with video, the drone would drift off-axis when flying a straight line, even when programmed to fly a straight flight.

This is so bad for professional use and needs to be fixed ASAP. And yes I have done several IMU and compass calibrations, plus remote cal as well.
 
I have the exact same problem with my P4P+ 2.0 as the OP. I did my first shoot with it on a night shoot last evening and the drone constantly drifted and rotated in hover mode. It made taking long exposures for stills impossible.

And with video, the drone would drift off-axis when flying a straight line, even when programmed to fly a straight flight.

This is so bad for professional use and needs to be fixed ASAP. And yes I have done several IMU and compass calibrations, plus remote cal as well.

I am seeing more and more reports of the same. There must be some real truth behind the communication that the USA based DJI support employee shared with me about this being a more widespread issue with several models....he still maintains a fix is on its way.

I would still put in a support ticket just so they know we are out here! They will recommend all the basics first (reset defaults, refresh firmware etc. which you can't do because there is nothing in the assistant to refresh or restore. They will also tell you to re-calibrate everything even though that won't help.) and then tell you to return it for repair. Seems to be standard practice for DJI front line support. In many cases they have no clue or current info. I am not sending mine in for repair because I would likely go thru all those hoops and end up right back where I started from if this is truly a firmware issue or a hardware issue that can be fixed with firmware.
 
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Geez, this is depressing news. I was about to sell my old P4P+ but now can’t until the drifting issue is fixed on the new 2.0. Thanks for documenting this. I’ll put a support case in to DJI, but not happy.
 
Usually takes 3-6 months to get the bugs out of any newly released DJI product. Best not to rush to be an early adopter. Wait 6 months for the dust to settle, and buy a tried and true P4P instead. It's been out over 18 months! Not many differences, other than one is mature and one is still in diapers!
 
I am having the same problem with my phantom v2 I thought I had it fixed when I read an article about getting the drone cool and then doing an IMU calibration. This helped for a few days but it is now drifting again and is not a permanent solution can’t tell you how many shots have been ruined due to this.
 
My contact at DJI was shipped a brand new 2.0 and his has the same issue.

Please make a support case just so the numbers with the issue keep climbing at DJI. They will recommend all their standard stuff and when that does not work, they will suggest you send it in for repair which likely won't work either.

I am choosing to sit and wait for a fix because if sent back, based on the number of folks that have the same issue, likely it would come back just as it went in.
 
My contact at DJI was shipped a brand new 2.0 and his has the same issue.

Please make a support case just so the numbers with the issue keep climbing at DJI. They will recommend all their standard stuff and when that does not work, they will suggest you send it in for repair which likely won't work either.

I am choosing to sit and wait for a fix because if sent back, based on the number of folks that have the same issue, likely it would come back just as it went in.
Therein lies the problem. Many of these early adopter problems are design defects/software issues that cannot be fixed with any current stock replacements. I went through TEN P4P's over 6 months trying to get a good one, but they were all from the same defective original stock! I purchased from B&H and Best Buy and Amazon. All had the same issues. Only after the P4A came out were the P4P gimbal flips, crooked horizons, and 4K 4096x2160 60fps video glitch issues finally sorted out, in a combination of design and FW updates!
 
Phantom 4 Pro 2.0 Firmware V01.00.1500 released


Phantom 4 Pro V2.0 Release Notes

Overview
  • Date: 2018.06.26
  • Aircraft Firmware: V 01.00.15.00
  • Phantom 4 Pro V2.0 Remote Controller Firmware: V 01.00.15.00
  • Phantom 4 Pro+ V2.0 Remote Controller Firmware: V 01.00.01.00
  • DJI GO 4 App iOS: V 4.2.20
  • DJI GO 4 App Android: V 4.2.20

What’s New?
  • Optimized compass calibration.
  • Optimized gimbal performance to improve its stability during flight.

Notes
  • Once the firmware has been updated, it cannot be reverted to a previous version. Restart the aircraft and remote controller once the update is complete.
  • If the firmware update fails, restart the aircraft, remote controller, and DJI GO 4 app/DJI Assistant 2, then try updating again.
 
Phantom 4 Pro 2.0 Firmware V01.00.1500 released


Phantom 4 Pro V2.0 Release Notes

Overview
  • Date: 2018.06.26
  • Aircraft Firmware: V 01.00.15.00
  • Phantom 4 Pro V2.0 Remote Controller Firmware: V 01.00.15.00
  • Phantom 4 Pro+ V2.0 Remote Controller Firmware: V 01.00.01.00
  • DJI GO 4 App iOS: V 4.2.20
  • DJI GO 4 App Android: V 4.2.20

What’s New?
  • Optimized compass calibration.
  • Optimized gimbal performance to improve its stability during flight.

Notes
  • Once the firmware has been updated, it cannot be reverted to a previous version. Restart the aircraft and remote controller once the update is complete.
  • If the firmware update fails, restart the aircraft, remote controller, and DJI GO 4 app/DJI Assistant 2, then try updating again.
Any volunteers to test the latest FW, especially knowing, in advance, that it is a one way update? ;)
 
I have already updated and am heading out for a flight. It forced an IMU calibration afterwards which tells me they did work on the sensors which is a good thing.

Due to the release notes, I am optimistic that this is intended to help the slow yaw turning and gimbal glitching that people have been experiencing.
 
I have already updated and am heading out for a flight. It forced an IMU calibration afterwards which tells me they did work on the sensors which is a good thing.

Due to the release notes, I am optimistic that this is intended to help the slow yaw turning and gimbal glitching that people have been experiencing.
At least the release notes actually state that the update addresses the issues. It's when they don't say anything relevant that you want to hold back!
 
I flew a short flight in between large thunderstorms. Very gusty conditions so I stayed below 20'.

This updated forced an IMU calibration, reset my EXP settings, reset my brake sensitivity settings, and reset many of the obstacle settings.

So far so good with this limited flight test. It is obvious they did some serious work on the compass and IMU code.

It appears they also changed the DAT file log format that gets recorded on the mobile device. They removed a ton of data fields!
Lost Signals.png
 
After the firmware update I flew a test mission this morning and trended/reviewed the logs for the issue with slow yaw while hovering.

So far the results seem promising! I performed the series of maneuvers that have proven to re-produce the issue on demand and the drift was non-existent to very minor.

It also seems that DJI fixed the braking response sensitivity issue that most were having where the drone was ignoring the sensitivity setting and braking at max braking effect no matter what. Now the drone seems to be responding to that setting and braking at more appropriate rates.
 
@BudWalker and @sar104 ,

Thought you guys might want to look at the logs of a before and after flight to see the huge improvement the firmware update made on the subject of this thread!

These are DAT files off the drone.

Before:
DJI_ASSISTANT_EXPORT_FILE_2018-06-27_16-39-45.FLY030.DAT

After:
DJI_ASSISTANT_EXPORT_FILE_2018-06-27_16-37-38.FLY047.DAT

These flights share the same hardware and compass cal. After the update the IMU had to be re-calibrated because the sensor status page had all 4 sensor status's showing huge bias numbers and the bar lines were all red. Many others that have reported updating have experienced the same forced IMU cal.

I would love to know the technical explanation of how they did what they did to fix this and what the root cause was.
 
After the firmware update I flew a test mission this morning and trended/reviewed the logs for the issue with slow yaw while hovering.

So far the results seem promising! I performed the series of maneuvers that have proven to re-produce the issue on demand and the drift was non-existent to very minor.

It also seems that DJI fixed the braking response sensitivity issue that most were having where the drone was ignoring the sensitivity setting and braking at max braking effect no matter what. Now the drone seems to be responding to that setting and braking at more appropriate rates.
Very encouraging!
 
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