Maps Made Easy created a little online utility for viewing the .DAT log files that the Inspire 1 records for every flight.  We needed a way to test our commanded flights against what was actually occurring.  We already had a decent log file viewer going so we figured we would add to it.  It turns out that it works perfectly for the Phantom 3 .DAT log files too!

UPDATE 8/9: We just released an update that enables the data to be read out to a CSV at the native rate.



Maps Made Easy Log File Viewer

Use the DJI Pilot app to enter "Flight Data Mode".  

1. Click the top right corner of the main screen to enter the settings menu.
2. Choose the blue highlight icon to enter the MC Settings menu.

3. Select Advanced Settings.
4. Select "Enter flight data mode".


There will be a prompt that tells you to connect the Phantom 3 via USB cable and you will be in flight data mode.
A drive will show up on your computer that contains a log file for the most recent times you have turned on your Phantom 3.  Old files get deleted.  These files are different that the ones in the folder on the SD card.

The .DAT files are pretty big because the data is being recorded at a couple hundred hertz, but we are only plotting the data for every 1 second so it would work with Google Charts.  We hope to have a full CSV dump of the available for download if there is interest.

Our viewer shows latitude and longitude plotted on a map and a graph that shows the ground speed and altitude vs time. We have most of the other numbers decoded, but these are the fun ones.  

A KML file is available for download, but keep in mind that it is recording the altitude that the Phantom 3 recorded and might show up slightly below the Google Earth surface.

The thread title leads us to believe your efforts support the .dat files form the Phantom 3 log, but the link shows other devices and nothing mentioned about the Phantom 3.

An oversight on your part, or more information to follow later?

Nice job sir!

aburkefl@gmail. Posted at 2015-5-27 05:11
The thread title leads us to believe your efforts support the .dat files form the Phantom 3 log, but ...

We just found out this morning that the Phantom 3 is the same file format.  The link will reflect the change in our next update.

We suspected that the P3 was the same format but weren't sure until we had a chance to get some files.  We kept selling all the ones we had in the shop and had nothing to test with!

gregg1r@mindspr Posted at 2015-5-27 05:24
Nice job sir!

Thanks! We needed the data and tend to specialize in such matters...

MapsMadeEasy Posted at 2015-5-27 05:44
We just found out this morning that the Phantom 3 is the same file format.  The link will reflect  ...

Many thanks for the clarification.

Great news.
When will flight planner be ready for P3

candubob Posted at 2015-5-27 07:20
Great news.
When will flight planner be ready for P3

There are a couple of issues to iron out still but I would expect that it would be available by the end of June if everything goes well with DJI and Apple.

How will the ready date be announced.  Shall I just keep checking on your site

candubob Posted at 2015-5-27 07:27
How will the ready date be announced.  Shall I just keep checking on your site

We'll post it all over the place.  Or follow @DronesMadeEasy or @MapsMadeEasy on Twitter.

Fantastic guys!!  It would be nice to also display the count of logged coordinate points that are contained in a submitted .DAT file.  I suspect that LOTS of other parameters are logged as well - control input events with their time-tags and such?

It takes a lot of time and effort to decode things like this.  We were able to find the numbers we needed and called it a day.  Also, we are a DJI dealer and don't want to make them mad.  If they tell us it is OK to post more, we might.

MapsMadeEasy Posted at 2015-5-28 01:40
It takes a lot of time and effort to decode things like this.  We were able to find the numbers we n ...

What is the point of a new app for this, when its built in to the Dji Pilot app?

gr8pics Posted at 2015-5-29 00:32
What is the point of a new app for this, when its built in to the Dji Pilot app?

This is the native data logger log files, not the low update rate txt files.  These files are created everytime the drone is turned on, regardless of whether or not the app is running.  These files are created when other apps are in use too.  The update rate on this data is around 200 Hz for a lot of the signals so you can do more with it.

If someone from DJI tells us on here that they don't mind, we will post a CSV dump of all the data we have decoded.

MapsMadeEasy Posted at 2015-5-29 05:54
This is the native data logger log files, not the low update rate txt files.  These files are crea ...

Don't get yourself too shook up over it as there are others out there that have been converting dji's .DAT files for some time now. As you probably know there are 3 .DAT files produced for each flight. I have counted 105 data columns in the largest of the 3 .DAT files alone. We can't never have too much data. I'd recommend you setup your converters to display all the possible data you are able to. No need to hide the data regardless how important you may think a data category is.

Btw, if you haven't noticed,  but dji has been going to great lengths to open things up in efforts to get the industry to evolve as much as possible, and then some.

1320frank@comca Posted at 2015-6-28 10:21
Don't get yourself too shook up over it as there are others out there that have been converting dj ...

We are mobile and on-board SDK developers as well as a dealer of DJI hardware, so we don't want to poke the bear.  They went the the trouble of obscuring it so we won't be posting the results without permission.

Apologies.

I am suffering from "cable stupidity" this morning, but what cable do I use to connect my iPad to the Phantom?  And does it connect to the gimbal or the USB port under the P3 logo?

(And why isn't there just one blasted Universal USB cable that connects everything to everything else?)

msjh Posted at 2015-6-28 15:09
Apologies.

I am suffering from "cable stupidity" this morning, but what cable do I use to connect m ...

You use your normal charging cable to connect to the controller to fly but you need to use a USB to micro USB like is used for lots of other USB devices to connect it to your computer.  I don't think you can read the DAT files off with an iPad.  Could be wrong, but a computer is your best bet.

MapsMadeEasy Posted at 2015-6-28 23:32
You use your normal charging cable to connect to the controller to fly but you need to use a USB to ...

Let's see if I have this right.

1. Connect iPad to controller using normal cable.
2. Start DJI Pilot app
3. Power on iPad, controller and P3
4. Go through steps 1-4 in your original message; on step 4 use a micro USB cable to connect P3 (hidden USB port) to iMac

Is that correct?

msjh Posted at 2015-6-29 01:52
Let's see if I have this right.

1. Connect iPad to controller using normal cable.

Yes. You have to be connected to the aircraft to be able to put it into flight data mode.  After that, you plug the aircraft directly into your computer to access it as you would a USB flash drive and copy the files off.

Just tried this utility: it's lovely!  Thanks.

However, on the right axis (altitude), altitudes are shown as negative numbers on the two flights I have uploaded so far.  I am not a skilled flyer, but I know I was not flying below sea level!  :-)

Thanks again.

msjh Posted at 2015-6-29 15:42
Just tried this utility: it's lovely!  Thanks.

However, on the right axis (altitude), altitudes are ...

Those are the numbers as they were recorded by GPS.  While GPS is notoriously bad at reporting accurate altitude readings, the barometric sensor is there to even things out.  It seems that most of the elevation related numbers are there for relative, not absolute, measurements.  

Do you guys get sensor info from these files? For instance if I had a crash and wanted to know if any of the sensors were reporting strange stuff would you be able to send me CSV logs of the data? Also do the files contain exception errors on the CPU? It would seem as if my log file stopped recording just before the crash.

looxonline@gmai Posted at 2015-7-13 00:32
Do you guys get sensor info from these files? For instance if I had a crash and wanted to know if an ...

The sensor data is stored in your DJI Pilot app on the iOS device. There are several applications out there that let you browse the file system of your iPhone/iPad.

I use iExplorer to grab the .TXT files, then use Flylitchi's log converter to generate the .CSVs that you can open in Excel.

Once you have the .TXT files go here, upload the log and it will create the .CSV file.

Once you've got it open in Excel you can use pivot tables to break down your data however you want to view it. Another neat Excel feature that work with this data is called Power Map. You have to enable it in your Excel Options -> Add-Ins / COM Add-Ins.

msjh Posted at 2015-6-28 15:09
Apologies.

I am suffering from "cable stupidity" this morning, but what cable do I use to connect m ...

There is a universal cable if you dont use an apple device ;-) every device I Have from the wife's blackberry to my bose headphones all use the micro usb end. Only apple needs a different lightning plug.

Highcastle Posted at 2015-7-13 08:30
The sensor data is stored in your DJI Pilot app on the iOS device. There are several applications o ...

I got the TXT file and renamed it to CSV but it shows up as a bunch of non-ASCII characters in excel. Not sure if there is more post processing that I need to do. Any advice?

looxonline@gmai Posted at 2015-7-13 18:49
I got the TXT file and renamed it to CSV but it shows up as a bunch of non-ASCII characters in exc ...

I apologize - I skipped the 'convert' step. Flylitchi has a log converter on their site that will return the correctly formatted .csv's.

Once you have the .TXT files just go here, upload them and it will generate the .csv.

Is it normal that transferring from Phantom 3 using this mode (usb cable in body) is very slow? I only get about 700 KB/s...

fredz Posted at 2015-7-17 20:28
Is it normal that transferring from Phantom 3 using this mode (usb cable in body) is very slow? I on ...

Yes I'm getting 500-600kbytes  per second maximum.

Hi MapsMadeEasy,

I'm uploading my .DAT log files to DJI for a recent incident that I experienced.

I'm using your log viewer web service on FireFox 34.0.5 and Safari 8.0.7 on Mac OS X (10.10.4) and get this following message on ALL of my 13  .DAT files:

"No valid data points.
No valid data points were found.

It is possible that this log file was taken while there was not a valid GPS lock."

I'm also not getting anything displaying on the Speed/Attitude/Time graph.

looxonline@gmai Posted at 2015-7-13 18:49
I got the TXT file and renamed it to CSV but it shows up as a bunch of non-ASCII characters in exc ...

Renaming the file does not change the structure of the file. You need to use flyitchi.com or DJILogs.com to convert the file to a CSV format and then Excel to view the resulting file.

joeztan Posted at 2015-7-17 23:09
Hi MapsMadeEasy,

I'm uploading my .DAT log files to DJI for a recent incident that I experienced.

There are a couple different DAT files that get created by the DJI systems.  The only ones that work with our viewer are the ones that are attained by following the steps above, not the ones that the Pilot app creates.  DAT is a common file extension for general data and there is no designated format for it.  

MapsMadeEasy Posted at 2015-7-18 02:24
There are a couple different DAT files that get created by the DJI systems.  The only ones that wo ...

Hi MapsMadeEasy,

Appreciate the advice, but I have followed your instructions to extract the .DAT files. The .DAT files were obtained by connecting a USB cable between the aircraft and my Mac, I then select "Enter Flight Data Mode" on the DJI Pilot app.

I see the Phantom drive mounted, select all 14 files (3GB in total) and copy it to my local drive. This takes 1 hour.

I'm feeding these .DAT files from the aircraft into your web app, not the .TXT log files from DJI's Pilot iOS app. Thank you.

joeztan Posted at 2015-7-18 19:51
Hi MapsMadeEasy,

Appreciate the advice, but I have followed your instructions to extract the .DAT ...

Interesting... There is a .DAT file created for every time the aircraft is powered up and it can get pretty hard to find the file you are looking for.  

Is there a file that is timestamped for the day that you had the "incident"?

We have tested the utility with files from lots of different Inspires and P3 with various firmwares and haven't had any issues yet. If you are still having issues you can email the file to us and we will give it a look to see that everything is the same.  

MapsMadeEasy Posted at 2015-7-20 04:54
Interesting... There is a .DAT file created for every time the aircraft is powered up and it can g ...

I'm uploading my logs now to Dropbox and will send you some links to some of the smaller files that I think are the relevant. Uploading will take a few hours, I'll post the links when I get home from work.

After my incident, I went back to my hotel room and discharged my batteries slowly to 60% storage charge. This took about 1-2 hours per battery and I had three batteries. Since this was done indoors that is why there is no GPS signal, but I hope the flight logs for the actual flight have not been overwritten. The flight logs date stamps for logs FLY107-FLY119 are the same (16 July 12:01am), only my final flight log has a date stamp that makes sense (FLY120.DAT 16 July 7:06pm).

I will post up a Dropbox link in 12 hours...

once im in flight data mode, I only fiind one file" P3X_FW_LOG_AB.txt.
is that the file to upload to the log file viewer?

MapsMadeEasy Posted at 2015-7-20 04:54
Interesting... There is a .DAT file created for every time the aircraft is powered up and it can g ...

Ok, uploaded a few sample log files.

https://www.dropbox.com/sh/2rec9 ... cAZhvOzdgajwaa?dl=0

Can you download some of the smaller ones and see if your log viewer is able to read these?

"No valid data points.
No valid data points were found.

It is possible that this log file was taken while there was not a valid GPS lock."

All of the log files report the same message.

I 'm running this on Mac OS X 10.10.4
Safari Version 8.0.7 (10600.7.12)
FireFox 39.0
Google Chrome Version 43.0.2357.134 (64-bit)

LICENSED PILOT Posted at 2015-7-21 10:58
once im in flight data mode, I only fiind one file" P3X_FW_LOG_AB.txt.
is that the file to upload to ...

You forgot the step where you plug the USB port on the drone directly into your computer... The files are stored in the flight controller so you need to plug in directly to read it.

joeztan Posted at 2015-7-21 05:32
I'm uploading my logs now to Dropbox and will send you some links to some of the smaller files tha ...

If the drone was on for 6 hours while you were draining the batteries, the files are gone. That is your problem.

First of all, you don't have to drain your batteries down for storage.  They will do it automatically after 7 days or so.

Second, a .DAT file is created for every time you turn it on, GPS lock or not.  Leaving it running for a few hours will blank anything you have currently saved.

If you have an incident that you are super concerned about saving the data for MAKE SURE IT IS UNPOWERED until you are ready to retrieve the data. We almost lost our data after a crash because it took us two hours to get to the mountain top where it was sitting there still on... We knew we had a ticking clock.

MapsMadeEasy Posted at 2015-7-22 00:36
You forgot the step where you plug the USB port on the drone directly into your computer... The fi ...

which plug, the one below the name plate or the on in the gimbal?