Hello Tello Pilot!
Join our DJI Tello community & remove this banner.
Sign up

Drone log

Ahmadreza

Member
Joined
Sep 11, 2018
Messages
22
Reaction score
8
Hi guys
Do you know how can I open tello's log files in app data folder? Files are .dat and no app can open them.
I'm curious about the data it gather...
 
Hi

You can use datcon to extract the information from the dat files to more useful file formats.
CsvView/DatCon
If you also pick up the csvtool , you can get nice graphs on several measurements it keeps.
(motors, battery voltage, baro, gyro, accel, etc.)
Below an example of motors output and voltage in red of a very uneventful 'drain my battery' flight.
csvtool.gif
 
  • Like
Reactions: DinoBaldi
Another cool feature is plotting Tello's flight path.

You only need to export .DAT file to .XLS (microsoft Excel sheet format). Then, select columns
Code:
MVO:PosX, MVP:PosY
and choose Insert Graphic from Excel toolbar. Setting clear background graphic and adding a google maps screeen-captured layer below you will get something like this:

tello datcon map.jpg

Take into account Tello's visual positioning is not 100% accuracy. Flight takeoff and landing spot were the same, althought in the map they are about 30 meters appart.

Note: If you notice Tello's path is reversed and displaced some Excel formula is needed. For this flight I really plotted:

Code:
north-south = MVO:posX * 100 - 6

east-west = MVO:posY * 100 - 21
 
Last edited:
Another cool feature is plotting Tello's flight path.

You only need to export .DAT file to .XLS (microsoft Excel sheet format). Then, select columns
Code:
MVO:PosX, MVP:PosY
and choose Insert Graphic from Excel toolbar. Setting clear background graphic and adding a google maps screeen-captured layer below you will get something like this:

View attachment 1710

Take into account Tello's visual positioning is not 100% accuracy. Flight takeoff and landing spot were the same, althought in the map they are about 30 meters appart.

Note: If you notice Tello's path is reversed and displaced some Excel formula is needed. For this flight I really plotted:

Code:
north-south = MVO:posY * 100 - 6

east-west = MVO:posY * 100 - 21
Interesting... See if I can make a Google maps overlay, calculate & draw it on maps itself after setting a start point.
 
You don't need both programs. DatCon is simplier.

I Use DatCon only for extracting flitght dat from Telllo's log. That´s enought form me as I post-process data using Microsoft Excel.

You can use CsvView for graphically viewing data from Tello's log or extracting flitght dat from Telllo's log too. BUT IT CAN'T PLOT TELLO'S PATH.
 
Hi, @BudWalker

Congratulations for your great apps. I would like to suggest you adding CsvView ability to plot Tello's route plotting values (MVO: PosX, MVP: PosY). Only math you need is:

Code:
north-south = MVO:posX * 100 - offset_x
east-west = MVO:posY * 100 - offset_y

Where offset_x and offset_y are the very first values detected by tello VPS.

Of course, you should plot route over a blank map page becouse data is not georeferenced.

Zip file attached for reference in this post. It contains a DAT flight log file sample and a Microsoft Excel Sheet plotting route and values.

Thank you for your excellent work.

Raul
 

Attachments

  • tello_route.zip
    4.6 MB · Views: 28
Last edited:
Hi, @BudWalker

Congratulations for your great apps. I would like to suggest you adding CsvView ability to plot Tello's route plotting values (MVO: PosX, MVP: PosY). Only math you need is:

Code:
north-south = MVO:posX * 100 - offset_x
east-west = MVO:posY * 100 - offset_y

Where offset_x and offset_y are the very first values detected by tello VPS.

Of course, you should plot route over a blank map page becouse data is not georeferenced.

Zip file attached for reference in this post. It contains a DAT flight log file sample and a Microsoft Excel Sheet plotting route and values.

Thank you for your excellent work.

Raul
Try this. Edit the file <CsvViewInstallDir>/defs/datGenericPlayers.pml
and insert this

<geoPath>
<name>MVO</name>
<symbol>M</symbol>
<Latitude>MVO:posY</Latitude>
<Longitude>MVO:posX</Longitude>
</geoPath>

into the <geoPlayer> definition at the bottom of that file.
 
  • Like
Reactions: raulvolador
@BudWalker ,

It worked ! It is amazing ! Thanks a lot for your helpl

I got this plot into CsvView GeoPath window:

csvview geopath tello.jpg

As you can see it's exactly the same shape as my previous Microsoft Excel attemp.

Only problem is route is not well oriented (it seems flipped on both axes) :(

By the way, Is there any chance showing a distance ruler in the window ?

My datGenericPlayers.pml bottom file is now this way:

Code:
<geoPlayer>
        <geopath>
            <name>AC</name>
            <symbol>A</symbol>
            <Latitude>IMU_ATTI(0):Latitude</Latitude>
            <Longitude>IMU_ATTI(0):Longitude</Longitude>
            <Altitude>General:relativeHeight</Altitude>
            <headingSignal>IMU_ATTI(0):yaw</headingSignal>
            <headingSignal>IMU_ATTI(0):magYaw</headingSignal>
           
        </geopath>
        <geoPath>
            <name>Home</name>
            <symbol>H</symbol>
            <Latitude>HP:Latitude</Latitude>
            <Longitude>HP:Longitude</Longitude>
        </geoPath>
        <geoPath>
            <name>MVO</name>
            <symbol>M</symbol>
            <Latitude>MVO:posY</Latitude>
            <Longitude>MVO:posX</Longitude>
        </geoPath>      
    </geoPlayer>
 
Last edited:
@BudWalker ,

It worked ! It is amazing ! Thanks a lot for your helpl

I got this plot into CsvView GeoPath window:

View attachment 1973

As you can see it's exactly the same shape as my previous Microsoft Excel attemp.

Only problem is route is not well oriented (it seems flipped on both axes) :(

By the way, Is there any chance showing a distance ruler in the window ?

My datGenericPlayers.pml bottom file is now this way:

Code:
<geoPlayer>
        <geopath>
            <name>AC</name>
            <symbol>A</symbol>
            <Latitude>IMU_ATTI(0):Latitude</Latitude>
            <Longitude>IMU_ATTI(0):Longitude</Longitude>
            <Altitude>General:relativeHeight</Altitude>
            <headingSignal>IMU_ATTI(0):yaw</headingSignal>
            <headingSignal>IMU_ATTI(0):magYaw</headingSignal>
           
        </geopath>
        <geoPath>
            <name>Home</name>
            <symbol>H</symbol>
            <Latitude>HP:Latitude</Latitude>
            <Longitude>HP:Longitude</Longitude>
        </geoPath>
        <geoPath>
            <name>MVO</name>
            <symbol>M</symbol>
            <Latitude>MVO:posY</Latitude>
            <Longitude>MVO:posX</Longitude>
        </geoPath>      
    </geoPlayer>
I suspect that the orientation isn't flipped in both axes. It's rotated 180°. You can avoid this problem by launching with the Tello pointing true North.

The GeoPlayer is based on lat/long coords. The MVO positional data is in meters I believe. So the GeoPlayer is being fooled into thinking the MVO data is actually lat/long data.

I'm involved in another (non drone) project for the next 6 to 9 months and don't have much time to implement new features. I'm just doing bug fixes and the like.
 
  • Like
Reactions: raulvolador
I suspect that the orientation isn't flipped in both axes. It's rotated 180°. You can avoid this problem by launching with the Tello pointing true North.

The GeoPlayer is based on lat/long coords. The MVO positional data is in meters I believe. So the GeoPlayer is being fooled into thinking the MVO data is actually lat/long data.

I'm involved in another (non drone) project for the next 6 to 9 months and don't have much time to implement new features. I'm just doing bug fixes and the like.

@BudWalker ,

I'm sorry you are so busy with your new proyects. :(

By the way, I'm pretty sure it's a flipping coordinates problem and not a rotation issue. See this another couple of samples: excel path vs GeoPlayer path. Is not possible match both routes by only rotation.

tello path excel.jpg
tello path csvview.jpg

I tried to invert coordinates at datGenericPlayers.pml file using a "minus" sign at -MVO: posY, but it doesn't worked (CsvView didn't recognize symbol)

Code:
<geoPath>
            <name>MVO</name>
            <symbol>M</symbol>
            <Latitude>-MVO:posY</Latitude>
            <Longitude>MVO:posX</Longitude>        
</geoPath>

I hope in a next future we can see Tello route path implemented into your great app.

Thanks a lot !

Raul
 
Last edited:
I got it !

It was so simple as swapping X and Y coordinates into datGenericPlayers.pml this way:

Code:
<geoPlayer>
        <geoPath>
            <name>MVO</name>
            <symbol>M</symbol>
            <Latitude>MVO:posX</Latitude>
            <Longitude>MVO:posY</Longitude>
            <Altitude>MVO:height</Altitude>           
        </geoPath>   
</geoPlayer>

Path is now showed perfect. No flipped route anymore. :)

csvview path mvo tello.jpg

It's great !

Raul.
 
Last edited:
  • Like
Reactions: BudWalker
I have managed to show rulers over Tello's route map !

I have created a 40 meters ruler, and others of 100 and 200 meters long.

You choose show/hide rulers pushing buttons located bottom GeoPath window:

tello csvview 40 meters ruler.jpg

tello csvview 100 meters ruler.jpg

tello csvview 200 meters ruler.jpg

You only need editing CsvView/defs/datGenericPlayers.pml file bottom this way:

Code:
<geoPlayer>
        <geoPath>
            <name>MVO</name>
            <symbol>M</symbol>
            <Latitude>MVO:posX</Latitude>
            <Longitude>MVO:posY</Longitude>
            <Altitude>MVO:height</Altitude>             
        </geoPath> 
        <geoPath>
            <name>40Meters</name>
            <symbol>4</symbol>
            <Latitude>err_code:mag_stat</Latitude>
            <Longitude>IMU_ATTI(0):quatY</Longitude>
        </geoPath>         
        <geoPath>
            <name>100Meters</name>
            <symbol>1</symbol>
            <Latitude>err_code:mag_stat</Latitude>
            <Longitude>IMU_ATTI(0):quatW</Longitude>
        </geoPath> 
        <geoPath>
            <name>200Meters</name>
            <symbol>2</symbol>
            <Latitude>IMU_ATTI(0):quatZ</Latitude>
            <Longitude>err_code:mag_stat</Longitude>
        </geoPath>         
</geoPlayer>

This way you can see route followed by Tello and calculate, approximately, its size and range.

Its cool !

Raul
-----
 
I got it !

It was so simple as swapping X and Y coordinates into datGenericPlayers.pml this way:

Code:
<geoPlayer>
        <geoPath>
            <name>MVO</name>
            <symbol>M</symbol>
            <Latitude>MVO:posX</Latitude>
            <Longitude>MVO:posY</Longitude>
            <Altitude>MVO:height</Altitude>          
        </geoPath>  
</geoPlayer>

Path is now showed perfect. No flipped route anymore. :)

View attachment 1984

It's great !

Raul.
Well, of course they were switched. Sorry about that.
 
I hope you can help me.

I gave my son a Tello for Christmas. Firmware update, then calibrated and off on the fields for the first start, first start and only clicked on the button "Auto TakeOff", the Tello lifted a few cm from the ground and before I could take over the control, she went up into the air until the connection is broken and I could not see her anymore. After a few minutes I had another signal and got a picture where the Tello was about to land but couldn't see where it was and shortly after that the battery of the Tello was probably empty. I didn't find them anymore.

My hope was now by reading the log data from the Tello and your map to be able to determine the approximate location where I can search. I did everything to customize the datGenericPlayers.pml but don't get the buttons for the scales 40m, 100m and 200m displayed. Without the scale I have no orientation. I only see the button "MVO Path"? Do you have an idea?

Also, I'm not quite sure which "dat" file to take from the Tello Log folder. From the time of the first flight of the Tello I have three DAT files. With the largest DAT file it shows me only somewhere before Africa a start and an end point. The middle DAT file looks similar to your examples but the scale is missing. In the smallest file no GPS data is found and therefore nothing can be displayed in GeoPlayer.
 

Attachments

  • droneLog.zip
    1.6 MB · Views: 19
for sure i will help you as soon i came back home and be able to use my computer, maybe january 2.

all the best.
 
Today I tried to read your LOG files into CsvView. I got this error messages from 1545821882163.DAT:

GeoPath 40Meters has signal err_code:mag_stat that isn't defined
GeoPath 100Meters has signal err_code:mag_stat that isn't defined
GeoPath 200Meters has signal err_code:mag_stat that isn't defined

I don't know what is the problem. Sorry :(
 

New Posts

Members online

No members online now.

Forum statistics

Threads
5,690
Messages
39,934
Members
17,023
Latest member
Repiv

New Posts