P3A Compass Issue

mjw

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Yesterday after take off, P3A was appx 10' off the ground, and about 15' away from me - (I have been flying the P3A for over a year) - suddenly I see the red bar on controller screen - Compass Error - drone went crazy - jumping all around - tried to land - would not respond, hit the ground, flipped over, broke a prop - turned the little dumpling' off - restarted, did the compass dance - took off - same display stating compass error once the drone was about the same distance and altitude away - successfully landed this time (only warning on screen prior to take off was a firmware upgrade was available) - anyone out there have any ideas what happened - do I need to do anything else - by the way the sensor reading were normal numbers in the 1500's........
 
The best option to begin with is, retrieve both flight logs preferably both flights and both the TXT and DAT files. Place the 4 files in a folder and zip it. Then place the folder in dropbox or google drive and paste the link here. This wont cost you any money, just a little time gathering the files.

I will (plus 1 or 2 others) analyze the file and hopefully find the issue.
 
I've only had it happen a couple of times and brought it down immediately. The first time it was going up and down about 4 feet, all over the place and I drove it straight at me and grabbed it out of the air and pulled the battery. It's usually caused by metal either underground or maybe a chair even, I'm not sure on the chair though. I hadn't calibrated and still usually don't but that time I calibrated it, changed locations by 30' and no problem. I was on top of an area where there had been a house years before and chalked it up to metal around and buried beneath me. The other time, there was metal all around underground and above and it was real hard to find a spot that didn't cause a compass error and that day was nuts... at my nephews house, he was a hoarder and there were tv's, refrigerators, bath tubs and burn piles with tons of nails from the pallets he burned for bonfires every night. Trying to find a place to take off to film for my niece was ridiculous... took me 4 times in 4 different areas just to get it into the air to film their yard.
 
The best option to begin with is, retrieve both flight logs preferably both flights and both the TXT and DAT files. Place the 4 files in a folder and zip it. Then place the folder in dropbox or google drive and paste the link here. This wont cost you any money, just a little time gathering the files.

I will (plus 1 or 2 others) analyze the file and hopefully find the issue.
are those the files found / stored on iPad =flight logs or the ones I will need to retrieve by connecting directly to the P3A? I appreciate the offer and will work on it tomorrow - by the way upon arrival back at my office I installed the firmware update - did that mess up the files we are to retrieve??
 
The best option to begin with is, retrieve both flight logs preferably both flights and both the TXT and DAT files. Place the 4 files in a folder and zip it. Then place the folder in dropbox or google drive and paste the link here. This wont cost you any money, just a little time gathering the files.

I will (plus 1 or 2 others) analyze the file and hopefully find the issue.
Sorry couldn't figure out how to zip the four files - I assume you wanted the text files from the 'LOGS' file - that what I have provided a link to - the .dat files were taken from the "FlightLogs" files both in the DJI app....let me know if this is what you requested - never did this before - once again thanks for your help
MJW

Dropbox - 2016-12-05[17][26][12](939).txt

Dropbox - 2016-12-05[10][49][50](836).txt

Dropbox - 2016-12-05 17_26_47.dat

Dropbox - 2016-12-05 10_50_25.dat
 
I've only had it happen a couple of times and brought it down immediately. The first time it was going up and down about 4 feet, all over the place and I drove it straight at me and grabbed it out of the air and pulled the battery. It's usually caused by metal either underground or maybe a chair even, I'm not sure on the chair though. I hadn't calibrated and still usually don't but that time I calibrated it, changed locations by 30' and no problem. I was on top of an area where there had been a house years before and chalked it up to metal around and buried beneath me. The other time, there was metal all around underground and above and it was real hard to find a spot that didn't cause a compass error and that day was nuts... at my nephews house, he was a hoarder and there were tv's, refrigerators, bath tubs and burn piles with tons of nails from the pallets he burned for bonfires every night. Trying to find a place to take off to film for my niece was ridiculous... took me 4 times in 4 different areas just to get it into the air to film their yard.
you may have a point - the compass issue happened both time at about the same location - there were pick-ups about 25' east and 20' SW of the drone - I had this happen one other time where the property and next door property had wrought iron fences
 
okay I figured out how to zip - learn something everyday

Dropbox - flightlog and log text files 12:5.zip

Mike, there seems to be problems with all that you posted. I will try and give you better details on how to go about this. To begin with, what you will be doing is placing each file in a Public folder and copying the link to each file and post them here like you did in post #5.

I'm not sure what happened on your end with the file names and such. Unless you have a P4 Pro or Mavic, the .dat file is uploaded from the AirCraft to the PC. Use the GOapp's Menu to activate the Flight Logs and save to PC. Each flight topically has 3 DAT files. From those 3 files you will want the one with the largest file size. The DAT file will look similar to FLY175.DAT. Save to DropBox.

The file you need is in the device you have the GO app loaded on. You must connect that device to your computer and search for a folder named DJI.
Open the DJI folder and locate folder dji.pilot.
Open the dji.pilot folder and locate folder FlightRecord.
Open folder Flight Record and scroll near the bottom of the page and look for the txt file matching the flight in question. That file will look similar to this:
"DJIFlightRecord_2016-08-23_[19-22-40].txt" Save to DropBox.
 
Mike, there seems to be problems with all that you posted. I will try and give you better details on how to go about this. To begin with, what you will be doing is placing each file in a Public folder and copying the link to each file and post them here like you did in post #5.

I'm not sure what happened on your end with the file names and such. Unless you have a P4 Pro or Mavic, the .dat file is uploaded from the AirCraft to the PC. Use the GOapp's Menu to activate the Flight Logs and save to PC. Each flight topically has 3 DAT files. From those 3 files you will want the one with the largest file size. The DAT file will look similar to FLY175.DAT. Save to DropBox.

The file you need is in the device you have the GO app loaded on. You must connect that device to your computer and search for a folder named DJI.
Open the DJI folder and locate folder dji.pilot.
Open the dji.pilot folder and locate folder FlightRecord.
Open folder Flight Record and scroll near the bottom of the page and look for the txt file matching the flight in question. That file will look similar to this:
"DJIFlightRecord_2016-08-23_[19-22-40].txt" Save to DropBox.
I have a P3A - to retrieve flight logs, logs and flight records folders - one has to use iTunes - in iTunes there are the three folders mentioned - then you have to save those folders to the PC, then something like HealthyDrones.com can open Flight Records - within the FlightRecords folder there are .txt files in the format you note above, in FlightLogs the format does not have the DJI stuff - but is just a format of 2016-12-5 09_50_53.dat
 
What kind of surface did you take off from? Did you recently do a compass calibration with metal items on your wrist or in your pocket? Were you near concrete or granite? Mine went crazy after taking off from a granite rock and I immediately flipped to atti mode and brought it home.

Sent from my SAMSUNG-SM-N920A using PhantomPilots mobile app
 
Here are .txt and .dat files from Flight Records and Flight Logs - the public folder stuff is beyond me hopefully you can open the link - I also uploaded the actual files....thanks
Dropbox - P3A .dat and .txt files.zip
 

Attachments

  • 2016-12-05 17_26_47.dat
    81 bytes · Views: 131
  • 2016-12-05 10_50_25.dat
    404 bytes · Views: 176
  • DJIFlightRecord_2016-12-05_[10-50-24].txt
    194.9 KB · Views: 165
  • DJIFlightRecord_2016-12-02_[13-59-55].txt
    1,005.1 KB · Views: 227
What kind of surface did you take off from? Did you recently do a compass calibration with metal items on your wrist or in your pocket? Were you near concrete or granite? Mine went crazy after taking off from a granite rock and I immediately flipped to atti mode and brought it home.

Sent from my SAMSUNG-SM-N920A using PhantomPilots mobile app
Concrete driveway - just a wedding ring, no keys - I think there was something in the ground - it was only about 10-12 above surface
 
Compass readings were all normal at take-off - they went crazy over the law..........yeah I take off from concrete all the time - I guess I ought to make a landing platform so takeoffs can be on a lawn surface.
 
Concrete driveway - just a wedding ring, no keys - I think there was something in the ground - it was only about 10-12 above surface
From your description and DJIFlightRecord_2016-12-02_[13-59-55].txt it's almost certain the problem you encountered was due to the rebar in the concrete. Compass calibration had nothing to do with this problem. I've described this issue a couple of times. Go to Spooky, first time i've almost lost it, what happened? to see a description. If you want we can take a look at your .DAT which is on the AC itself, not the tablet. Go here to see how to retrieve that .DAT It is large so you'll need to Dropbox it.
 
If you are compass dance at every flight location then you are doing it wrong. You are essentially snap shotting a bad compass at take off. And then when the phantom is higher in the air, it then sees the correct North and gets confused and conflicted.
You should only need to compass once at an open grassy field and that's it!!!
The only other time is if you decide to add bits or use a screwdriver near the compass leg.
Or if you travel far east/west to a different magnetic declination. Eg, Sydney Australia to Auckland New Zealand.
 
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If you are compass dance at every flight location then you are doing it wrong. You are essentially snap shotting a bad compass at take off. And then when the phantom is higher in the air, it then sees the correct North and gets confused and conflicted.
You should only need to compass once at an open grassy field and that's it!!!
The only other time is if you decide to add bits or use a screwdriver near the compass leg.
Or if you travel far east/west to a different magnetic declination. Eg, Sydney Australia to Auckland New Zealand.
Rarely calibrate via dance - I look at advanced settings / sensors - if the far left # (forgot name) is 1400-1800 the compass is in good shape - this was an odd occurrence - did not know what else to do - figured it couldn't hurt......thanks
 
You're welcome. I had a similar situation and dji had me do that and it worked. I doubted it would but what I know might fill a thimble


Sent from my iPad using PhantomPilots
 
Rarely calibrate via dance - I look at advanced settings / sensors - if the far left # (forgot name) is 1400-1800 the compass is in good shape - this was an odd occurrence - did not know what else to do - figured it couldn't hurt......thanks
Based on the 2 txt flight log files that were attached in post #11 there was NO calibrations that took place. :eek:
 

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