Ok, thanks!
No, I haven't retrieved a .DAT-file before but I've found your info about how to do it. I'll try it and come back.
Testing Follow me-mode, fly away and crash :( - happy ending! :)
- Thread starter AndersGB
- Start date
No, I haven't retrieved a .DAT-file before but I've found your info about how to do it. I'll try it and come back.
True the Phantom may have had 18 satellites but, in Follow Me mode, the Phantom is tracking the GPS in your phone or tablet. Being on the ground it doesn't have the same sky view as the Phantom and if your location jumps around the Phantom will obediently "follow" where it thinks you are.
Step 1-4, no problem.
I have a MacBookAir, and in step 5 I get problems. The SD card doesn't show up, neither in Finder or in Disc Utility. I've connected the cable in the plug in the nose of the P3 and to my computer. But no card is showing up. I've turned off both the P3 and the controller and tested it again. But no SD card. Do you have any idea what I'm doing wrong?`
I'm not a Mac person. But, @happydays is. When he sees this maybe he can help you figure out how to do it
While in Flight Data Mode with everything connected, open the Disk Utility application on the Mac.
There the internal Phantom SD card is displayed as an unmounted disk. If you can mount it, you can extract the .DAT files straight away.
If it's not possible to mount the disc(it often isn't) using Disk Utility, select the SD card and created a Disk Image of the entire Phantom SD card saving it to my computer hard drive. To do this, select the SD Card, then File>New Image>Blank Image and save the file to desktop.
After it has completed open the Disk Image as any other folder and save the enclosed .DAT files to a new folder for viewing.
However, depending on how many .DAT files (flights) there are, it can take a long time to create the rather sizable disk image of the entire SD card.
(The Phantom battery can often get run down in the process. Start with the battery at least 50% charged).
I hope this helps.
There the internal Phantom SD card is displayed as an unmounted disk. If you can mount it, you can extract the .DAT files straight away.
If it's not possible to mount the disc(it often isn't) using Disk Utility, select the SD card and created a Disk Image of the entire Phantom SD card saving it to my computer hard drive. To do this, select the SD Card, then File>New Image>Blank Image and save the file to desktop.
After it has completed open the Disk Image as any other folder and save the enclosed .DAT files to a new folder for viewing.
However, depending on how many .DAT files (flights) there are, it can take a long time to create the rather sizable disk image of the entire SD card.
(The Phantom battery can often get run down in the process. Start with the battery at least 50% charged).
I hope this helps.
Well, well, you won't believe me. I tried this a couple of times but no SD card showed up. Maybe something is broken inside I thought. Then I tested if I could read the SD card for the camera (the gimbal is broken but the "platform" above it is intact). I couldn't read that card either. Hmm. I then tested the USB cable with an external drive. It didn't show up either. So I found another cable, and simsalabim, it worked!
So the cable I got with the Phantom was the problem, it is broken.
Now I've retrieved the .DAT file and uploaded it to Dropbox. I will post a link to BudWalker. Many thanks for your help.
I've had this exact thing happen on multiple occasions to me. I was in the middle of the lake having the bird follow me on a seadoo when it lost signal and started to hover. I drove back within range of it and initiated follow me again and as soon as I hit apply, she bolted to the opposite side of the lake that I took off from. Switched it into gps and then aTTi mode immediately and got her under control.
Sent from my iPhone using PhantomPilots mobile app
Sent from my iPhone using PhantomPilots mobile app
OK, seems to be more common than I thought, haven't read about it earlier on this forum. Maybe the Follow Me mode needs some more work from DJI, perhaps some extra intelligence in the software. I will be very cautious to use it in the future. Thanks for you information.
Hi, I think you are looking at the wrong flight still.
Yea somethings weird on that deal. I did just look for what I was referring to in this thread but no sign of it.
Do you know which .dat flight was of the crash? FLY***?
Last edited:
Does this look like the right flight? The red is the location of the P3. The green is what the P3 thinks is the location of the RC.Well, well, you won't believe me. I tried this a couple of times but no SD card showed up. Maybe something is broken inside I thought. Then I tested if I could read the SD card for the camera (the gimbal is broken but the "platform" above it is intact). I couldn't read that card either. Hmm. I then tested the USB cable with an external drive. It didn't show up either. So I found another cable, and simsalabim, it worked!
So the cable I got with the Phantom was the problem, it is broken.
Now I've retrieved the .DAT file and uploaded it to Dropbox. I will post a link to BudWalker. Many thanks for your help.
I've attached the .kml with .txt extension. I.e.change FLY075.kml.txt to FLY075.kml and view it with Google Earth.
Lemme know if this is the right flight. I'll want to look some more at it when I know it's the right one.
Last edited:
Which app are you using when this happens to you? So far I've only seen this problem when the DJI Go App is being used for Follow Me.
Viewing the tablet location in Google Earth doesn't convey the abrupt, unrealistic change in location of the RC. Plotting the tablet longitude and latitude each against time looks like
Clearly, this abrupt change is an error.
For fun, I plotted the tabletLongitude and velocity
This shows the P3 racing off as a result of the RC location error.
Clearly, this abrupt change is an error.
For fun, I plotted the tabletLongitude and velocity
This shows the P3 racing off as a result of the RC location error.
Looks like you have confirmed this wasn't a Phantom error but a tablet GPS location hiccup. The Phantom was dutifully tracking the reported tablet location as requested. I assume the Phantom's data file records the RC location & that's how you were able to plot it on the graph?
Yes, the RC location is recorded in the P3's .DAT file. But, only during a Follow Me mission. If the DJI Go App is being used the RC location gets recorded in the binary part of the .DAT. If, instead, a third party app is being used for the Follow Me mission the RC location gets recorded in the eventLog which is in the text part of the .DAT file.
Now that is pretty cool. I have to say the P3 has some sophisticated & impressive data logging features! Worthy of Boeing!
Sorry, I've been sleeping, I'm in a different time zone.
Yes, it is the right flight. The green RC location lines to the left of my starting point (below the red starting point to the left) are incorrect.
Many thanks, very informative graphs!
So the P3 recorded an RC location far to the west (incorrectly) when I initiated Follow Me, and then it got a correct RC location when the mission had started and thought it was far off and should go to to the east. And crashed into the tree.
So the probable cause is that the P3 got an incorrect GPS location from the tablet for the Follow Me mode in the exact moment as the Follow Me mode was initiated.
I agree, probably true.
However, the strange thing is that when I look at the flight in my iPad (I click the actual Flight Record in my iPad and then I can watch the whole flight mapped on Google Earth, with the P3 and the RC) the RC is mapped in its correct position the whole time, it doesn't go away to the west suddenly. I don't know how often this information is sampled but this information indicates that there is a probable P3 error when recording the RC position when initiating Follow Me. What do you think?
If the P3 got an incorrect tablet location to the west, why would it shoot off to the east. I am wondering if the false location was to the east way off the map. If you zoom out of the map are there any green dots to the east?
Similar threads
