Hi Please could someone help me if you could . I bought a Phantom 4 pro 2 weeks ago from the DJI shop in Hong Kong and have just had endless problems . My newest problem is this : 1 : The Bird leans to the left when its hovering , its not straight . Does this matter ?      If i change it from "GPS" mode to "Alti" mode it straightens itself staright away and is dead level. Normal ? 2 : I am getting totally incorrect alltitude on my ipad when flying , eg : says i am at 8 meters when i am nearly on the floor. 3 : When i fly it a few meteres ( Just over head hight ) off the floor to the left or the right  it starts to decend while going left or right , if i keep going after about 100m it will hit the floor if i keep going !!  Does not seem to do it when its very high though. Thanks in advance Greg

You need to do an IMU calibration. Follow the steps below.

I use IOS with IPHONE 6S+, but NO am not promoting IOS over ANDROID. This out of the way:

With every drone I receive I do the following the first and only time until I get future notification form the app.

Take battery and props off, leave it outside in cold temperature for at least 1/2 hour have your remote on and ready and bring AC back in, put the battery in and start RC/AC/APP, DO NOT UPGRADE, run the IMU calibration. Need to follow the screen EXACTLY. Again if it got stuck it means it is waiting for the correct position of the AC.

After that do shut everything off, TURN everything back on in the same order as before and then do an AUTOMATIC Gimbal calibration.

After that do shut everything off, TURN everything back on in the same order and NOW do the upgrade if needed. Again, fast internet or fast data connection.

Where you take off make sure you don't any metal, elcetronic or megnatic interference, keys, etc.

Let us know... If it did NOT work than start a CASE with support.

You may want to re flash your firmware too.

dronist Posted at 2017-2-20 08:33
You need to do an IMU calibration. Follow the steps below.

I use IOS with IPHONE 6S+, but NO am not promoting IOS over ANDROID. This out of the way:

Thanks , i have already done an IMU calibration and did not help , but will do again in your order like you said.  Is it worth callibrating the VPS sensors ?
greg

gregcrammond72 Posted at 2017-2-20 09:02
Thanks , i have already done an IMU calibration and did not help , but will do again in your order like you said.  Is it worth callibrating the VPS sensors ?
greg

I would also cal the sensors, and make sure your AC  RC & Battery firmware are updated, your problem does sound like IMU, your aircraft should sit very straight while hovering, it is the IMU that be correcting this fall off, I will post you a small piece I wrote on how IMU works, it will give you a better understanding of how it works..

Good Luck..

gregcrammond72 Posted at 2017-2-20 09:02
Thanks , i have already done an IMU calibration and did not help , but will do again in your order like you said.  Is it worth callibrating the VPS sensors ?
greg

IMU "Inertial measurement unit"

As far as I see it, IMU calibration on a level surface updates a table of values the flight controller software uses as a reference for a level stationary hover. From there the craft responds predictably to flight commands.  It also likely measures any sensor noise and thermal drift so that these technical imperfections are accounted for when using IMU sensor data in flight. - this is likely why there must be no vibrations during the calibration process.


Bad IMU calibration could cause drift and attitude issues as the flight controller fights to hold the craft in what it thinks is the correct attitude as opposed to the correct physical attitude.


The IMU usually has 2 types of sensors – angle and acceleration and in turn 3 sensors of each type measuring in the X,Y and Z axis. These sensors can, through vibration, aging, impact etc, drift in their response over time and thus an IMU calibration will establish a new reference for the IMU’s level/stationary state that the flight controller can work with to restore stable flight.


Think of calibration as the bringing back into line the measured craft attitude with the true physical craft attitude.


As to how often an IMU calibration is needed, I wouldn’t like to say; certainly after any impact or if there are suspicions the craft can’t hover in a level attitude in a windless environment. Also after a firmware update is a good opportunity just in case the stored values get corrupted or are incompatible with the later firmware.

Although dji now say not to do IMU calibration until prompted, in your case I think you should..

Good Luck...

hallmark007 Posted at 2017-2-20 09:18
I would also cal the sensors, and make sure your AC  RC & Battery firmware are updated, your problem does sound like IMU, your aircraft should sit very straight while hovering, it is the IMU that be correcting this fall off, I will post you a small piece I wrote on how IMU works, it will give you a better understanding of how it works..

Good Luck..

Thanks so much

hallmark007 Posted at 2017-2-20 09:18
I would also cal the sensors, and make sure your AC  RC & Battery firmware are updated, your problem does sound like IMU, your aircraft should sit very straight while hovering, it is the IMU that be correcting this fall off, I will post you a small piece I wrote on how IMU works, it will give you a better understanding of how it works..

Good Luck..

one last thing , sorry for all the questions , to update all the things you said do i use the dji assistant software ?

gregcrammond72 Posted at 2017-2-20 09:24
one last thing , sorry for all the questions , to update all the things you said do i use the dji assistant software ?

Yes it's probably best to use assistant,

Also remember after you update all this if your P4p is still not right, I would return under warranty, it's a lot of money to spend for something that's not right.

Hopefully it might be ok..

Good Luck...

gregcrammond72 Posted at 2017-2-20 09:24
one last thing , sorry for all the questions , to update all the things you said do i use the dji assistant software ?

I have IOS and I have never used Assistant 2 to update always phone (IPHONE6S+) or MINI4  but I ONLY used the Assistant to calibrate the sensors. You can go either way but make sure you have fast internet or data connection

Please keep us posted with the performance after you do all the methods mentioned above, thanks.

DJI Natalia Posted at 2017-2-20 23:06
Please keep us posted with the performance after you do all the methods mentioned above, thanks.

Hi
thanks for getting back to me . I have done all the things above and going to fly later today and will let you know .
Thanks
greg