Compass and Yaw errors

[heaikak]

Hello all.

I have had my MP for soon a week, and flown roughly 56k meters or 187k feet during theese cold winter days.

Flying conditions have been harsh, ranging from -20c to -33c , with high humidity at times. I am well aware that this isnt within the specifications for the AC, thus I'm flying with full responsibility for damages. I am planning to use the MP for herding reindeer (at least checking up on them), so it's crucial I learn to fly in terrible conditions, as well as understand the hard limitations of this AC.

This morning when starting the GO4 app, it asked for an update, so I updated it. Afterwards I fixed all my Go4 settings, before doing a IMU/Compass calibration to be safe. I am located at latitude 69.5 , so both magnetic interference and angle to GPS can be a problem.

I have read up on the MP, as well as UAVs in general. I know how to properly calibrate the compass and do pre-flight checks.

However, all the flights today I experienced weird behaviour from the AC. Compass and Yaw errors, speed error (speed could be due to ice build up) etc. I lost GPS lock a few times today, and had to fly home in ATTI mode. RC also lost connection at least once.

Could someone look at my logs shared on Airdata, and tell me what is going on? At least one of the logs is not there, due to an app crash mid-flight.

PS! I have never owned a drone previously, nor have I tryed troubleshooting them. So please tell me if my logs need to be in a specific format.

Airdata UAV - Flight Data Analysis for Drones (Updated to allow CSV download)
Airdata UAV - Flight Data Analysis for Drones
Airdata UAV - Flight Data Analysis for Drones

Airdata UAV - Flight Data Analysis for Drones - Yesterday (previous to update) , a successfull flight.

 

[sar104]

Hello all.

I have had my MP for soon a week, and flown roughly 56k meters or 187k feet during theese cold winter days.

Flying conditions have been harsh, ranging from -20c to -33c , with high humidity at times. I am well aware that this isnt within the specifications for the AC, thus I'm flying with full responsibility for damages. I am planning to use the MP for herding reindeer (at least checking up on them), so it's crucial I learn to fly in terrible conditions, as well as understand the hard limitations of this AC.

This morning when starting the GO4 app, it asked for an update, so I updated it. Afterwards I fixed all my Go4 settings, before doing a IMU/Compass calibration to be safe. I am located at latitude 69.5 , so both magnetic interference and angle to GPS can be a problem.

However, all the flights today I experienced weird behaviour from the AC. Compass and Yaw errors, speed error (speed could be due to ice build up) etc. I lost GPS lock a few times today, and had to fly home in ATTI mode. RC also lost connection at least once.

Could someone look at my logs shared on Airdata, and tell me what is going on? At least one of the logs is not there, due to an app crash mid-flight.

PS! I have never owned a drone previously, nor have I tryed troubleshooting them. So please tell me if my logs need to be in a specific format.

Airdata UAV - Flight Data Analysis for Drones (0145 - self reference)
Airdata UAV - Flight Data Analysis for Drones
Airdata UAV - Flight Data Analysis for Drones

Airdata UAV - Flight Data Analysis for Drones - Yesterday (previous to update) , a successfull flight.

You didn't enable "Download CSV" for the flight in question, which makes analysis difficult. It would be better either to post the txt log file directly, or upload it to PhantomHelp which doesn't require you to have a subscription to enable download of the original log.

 

[heaikak]

You didn't enable "Download CSV" for the flight in question, which makes analysis difficult. It would be better either to post the txt log file directly, or upload it to PhantomHelp which doesn't require you to have a subscription to enable download of the original log.

@sar104 : I updated the link to allow CSV download.

I will read up on sharing the txt log. Not sure how it's done as of now

UPDATE: I remembered that I had a minor "flyaway" on first hover test, due to compass error. I upgraded the firmware (all software too), and re-calibrated. That fixed the issues and I have been flying for nearly a week without major problems. Just after this morning update I had problems again.

Thanks for your interest. Appreciated. I'm well aware that my flying conditions are quite extreme, and some people might disapprove of me trying.

 

[sar104]

@sar104 : I updated the link to allow CSV download.

I will read up on sharing the txt log. Not sure how it's done as of now

UPDATE: I remembered that I had a minor "flyaway" on first hover test, due to compass error. I upgraded the firmware (all software too), and re-calibrated. That fixed the issues and I have been flying for nearly a week without major problems. Just after this morning update I had problems again.

Thanks for your interest. Appreciated. I'm well aware that my flying conditions are quite extreme, and some people might disapprove of me trying.

OK - that's actually going to require the onboard DAT file to figure out what was happening. There was nothing wrong on the GPS side (plenty of satellites) - it exited P-GPS mode because of the compass errors. And there was no loss of uplink or downlink on that flight.

How to retrieve a V3 .DAT File from the AC

 

[heaikak]

@sar104 , I'm transferring them to the PC now. Give me a few minutes. Will share a Dropbox link

 

[heaikak]

@sar104 , here is the Dropbox link:
Dropbox - DJI_ASSISTANT_EXPORT_FILE_2017-12-27_22-29-10.DAT

I am not sure how many flights I included. There were a few "flights" with datetime's that seem correct.
27th December @ 1:45 PM
27th December @ 12:26 PM
27th December @ 11:55 AM

 

[sar104]

@sar104 , here is the Dropbox link:
Dropbox - DJI_ASSISTANT_EXPORT_FILE_2017-12-27_22-29-10.DAT

I am not sure how many flights I included. There were a few "flights" with datetime's that seem correct.
27th December @ 1:45 PM
27th December @ 12:26 PM
27th December @ 11:55 AM

There were three DAT files in that set, but none was an actual flight. The times were:–

FLY012: 2017-12-27 12:08:48 GMT
FLY013: 2017-12-27 12:12:24 GMT
FLY018: 2017-12-27 12:12:24 GMT

Are there any other possibilities?

 

[heaikak]

@sar104 , i tryed looking through all the dats. But the last flight recorded in DAT files is 2017-12-22 - as it looks.

Will try to dig deeper. Any other storage place for DAT files?

 

[heaikak]

So i tryed opening the DAT files from my phone in DatCon and CsvView. The files seem mostly empty. The text log file is less then 40 lines, and CsvView is not finding anything.

A file named 17-12-27-01-43-33_FLY014.DAT is 7771KB , but seems to contain nothing when opened.
Link to the file: Dropbox - 17-12-27-01-43-33_FLY014.DAT

The Go4 app had a lot of DAT files for FLY013 for 27th as well, looks wrong, but interesting. Added folder:
Dropbox - FLY013-DATS

Link to TXT files from Go4 app for flights in the problem period:
Dropbox - TXT

Theese flights are not found in any of the DAT files from the AC itself. How can this be?

 

[BudWalker]

So i tryed opening the DAT files from my phone in DatCon and CsvView. The files seem mostly empty. The text log file is less then 40 lines, and CsvView is not finding anything.

A file named 17-12-27-01-43-33_FLY014.DAT is 7771KB , but seems to contain nothing when opened.
Link to the file: Dropbox - 17-12-27-01-43-33_FLY014.DAT

Link to TXT files from Go4 app for flights in the problem period:
Dropbox - TXT

Theese flights are not found in any of the DAT files from the AC itself. How can this be?

Which version of CsvView are you using? These from 17-12-27-01-43-33_FLY014.DAT

 

[heaikak]

Which version of CsvView are you using? These from 17-12-27-01-43-33_FLY014.DAT
View attachment 27547

View attachment 27548
View attachment 27549

Hello @BudWalker , I am using version 1.3.8, downloaded from datfile.net yesterday.
When opening that specific file the dialog box says
"
SigPlayerProto MagMod/Compass Error has signal nonGPSCause that isn't defined
SigPlayerProto gpsHealth has signal gpsHealth that isn't defined
SigPlayerProto gpsHealth has signal flyCState that isn't defined
GeoPath Home has signal HP:Latitude that isn't defined
"

 

[heaikak]

This is what I find by DJI Assistant from the AC itself (See attached image):

Link to the 2 DAT files from image for 27th of December (Not touched on PC):
Dropbox - Assistant-27-12-2017

 

[BudWalker]

Hello @BudWalker , I am using version 1.3.8, downloaded from datfile.net yesterday.
When opening that specific file the dialog box says
"
SigPlayerProto MagMod/Compass Error has signal nonGPSCause that isn't defined
SigPlayerProto gpsHealth has signal gpsHealth that isn't defined
SigPlayerProto gpsHealth has signal flyCState that isn't defined
GeoPath Home has signal HP:Latitude that isn't defined
"

That's because you're looking at a tablet .DAT that has less signals than the AC .DAT. MagMod/Compass, gpsHealth, etc. are saved SigPlayer configurations that are distributed with CsvView. It's just saying that when you select a saved SigPlayer, e.g., gpsHealth, it won't be able to included the gpsHealth signal because it doesn't exist. When you select gpsHealth

You'll get this plot


Instead of something like this

which comes from a .DAT on your AC

 

[heaikak]

@BudWalker , ahh thank you very much.

Will have another look at it. This is all very new to me.