erratic flight independent of controller

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Can anyone help me solve why my P4 Adv with built in controller (GL300E) is flying erratically and performing actions without any input from the controller (e.g. ascending to max. height with both sticks untouched; descending 10-15 ft when it should be hovering; drifting when it should be hovering (in no wind); with good GPS signal during all of the above. I have reinstalled the aircraft firmware while on DJI support with no improvement, and am about to reinstall the Controller firmware once I can track down a micro CD reader, but would appreciate any other input from veterans...
 
(e.g. ascending to max. height with both sticks untouched; descending 10-15 ft when it should be hovering; drifting when it should be hovering
In the above statement its sounds like it could be a VPS issue. You will need to check your flight logs to verify. If you need assistance with that feel free to ask.
 
In the above statement its sounds like it could be a VPS issue. You will need to check your flight logs to verify. If you need assistance with that feel free to ask.
Sure! I have synced the flight logs, but can't find instructions on what to do next to consult the log (can view it and confirm that the actions of the P4 are independent of the control sticks)
 
I have synced the flight logs, but can't find instructions on what to do next to consult the log
Upload your .txt log file to the link below. You can view the flight and/or download the .csv for further analysis ( preferred ).
If you would like others to assist you, post a link to the uploaded file back here and we can certainly do that.
( Instructions are on the link )

Log Viewer
 
Thanks. Here is the link to my uploaded flight log: DJI Phantom Accessories & Tips | Phantom Help the uncontrolled ascent begins at about 3 min. There does seem to be something quite wrong with the VPS system. I have also downloaded a .csv file in case this link isn't the right thing to provide....
I had a very similar experience a few days earlier, but have not uploaded that log as its much longer..
 
Thanks. Here is the link to my uploaded flight log:
That is only the link to the Phantom Help Site....try again. We need the actual log link.
 
Ok, I am curious to know a couple of things which I will say in a moment. First, the VPS does look a bit erratic. But the increase in altitude without input was during a issuance of RTH. Second, you were too close to the home point for RTH therefore the aircraft will autoland. A force landing also was issued apparently due to the erratic VPS altitude telling the aircraft it was close to the ground. Lastly my question. Near the end of the flight there was a switch to ATTI mode. Did you do this manually? If Not I will look for a cause but your sats and Nav Health was fine. I would try a flight with the VPS turned off.

112723
 
Thanks. the first ascent without input was not during a RTH, or at least, I didn't initiate an RTH until after it had ascended and didn't seem to be coming down when I tried to bring it back down, or letting me fly it back, so it initiated RTH.
I did switch it to ATT mode to get it back close to my Home point becuase it didn't seem to be coming down or letting me bring it close to home during the RTH.

So, you recommend flying with VPS turned off, rather than (re)calibrating the VPS?
 
Thanks. the first ascent without input was not during a RTH, or at least, I didn't initiate an RTH until after it had ascended and didn't seem to be coming down when I tried to bring it back down, or letting me fly it back, so it initiated RTH.
I did switch it to ATT mode to get it back close to my Home point becuase it didn't seem to be coming down or letting me bring it close to home during the RTH.

So, you recommend flying with VPS turned off, rather than (re)calibrating the VPS?
Gezz I reckon just imu calibration and a new stick calibration,,good to try to find out what caused this so if going to do vps just do imu, if not work dig deeper again
 
So, you recommend flying with VPS turned off, rather than (re)calibrating the VPS?
You could attempt a re-cal on the VPS, but this data looks odd and from this I can't definitively conclude that it is a VPS issue with the un-commanded ascent. We may need the aircraft .dat file or the tablet .dat to make further analysis. You can see the VPS dropouts below. @sar104....what do you think?

112724
 
Me post this anyway
20190709_094632.jpg
,,this imu calibration sposed to sort these issues.....personally this where I would start,if it not fix then I would dig deep,,the op probly confused as and should start simple with the basiCS to try fix
 
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this imu calibration sposed to sort these issues
Personally, if this were an IMU issue, the aircraft would have been disoriented. It does not explain the un-commanded ascent of over 65 meters. I do recall seeing this issue before quite a while back and if I am not mistaken it was indeed a VPS issue. Good post for the record BTW.
 
The VPS altitude tells the story.
What's causing the drone to think it's still on the ground for much of the flight?
That's the whole issue. You can forget about the IMU.
Do you have a gimbal guard or something else blocking the view of the downward facing sensors?
 
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OK I confused now,,don't the vps info go through the imu calibrations.....I just had to ask
Screenshot_20190709-121721.jpg
 
The IMU is not the problem ... post #14 explains what is
OK but don't all that work through the same system meaning imu
I know 1 side off vps sends sonar click and other side receive it back and thought imu sorts this without calibration of the vps unit,,unless of course it does have a fault it won't fix,it might need vps calibration with assistant,,,,,sorry if I wrong but this what I thought
 
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OK but don't all that work through the same system meaning imu
Somewhat Yes....but we would need to see the .dat to localize anything further. It is best to find the issue, before introducing new variables that would skew the results.
 
thought imu sorts this without calibration of the vps unit,,unless of course it does have a fault it won't fix,it might need vps calibration with assistant
His VPS sensors are seeing something and reporting it.
EIther there is something blocking the view of the sensors or the sensors are dirty.
 
Am coming to the conclusion that the problem is a gimbal protector that came with the landing gear extenders I purchased a few weeks ago. Will test in a couple hours and if this proves the problem, will update and apologize. In case anyone's interested, this is the flight from a couple weeks ago where things seem to have started to go wrong (the first discrepancy in my logs btw the IMU altitude and the VPS altitude (initially a few inches, then ~ 10 ft 'low', then 'on the ground already; subsequent flights have all had the issue of the VPS system reporting 'on the ground' the entire time, reporting landings while > 100 ft agl, etc)): DJI Flight Log Viewer - PhantomHelp.com
 
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