The brightness change is made by me to get the focus .. DaVinci Resolve transition effect only.
Let me add another detail of this incident. : When the drone started moving back I tried to ascend the drone. So the drone moved back when it saw the river at about 1,2 meters height from the water. In order to avoid from crashing the trees I moved it up. I tried the same thing there twice. In one of them I managed to ascend the drone high and it flew as normal. When I get closer to the water it does the same losing-control again.
My observation is that this is a fairly classic example of RF energy interfering with the drones systems, both internal and the control link. This can be caused by a transmitter that causes the system to be blanked or overloaded, or other signal degradation effects. Please remember that these drones are not shielded to the extent that something for commercial use may be, and that a strong signal emitted nearby can disrupt both the internal components (e.g.: imu) and the control link back to the operator. A remote sensor like a river gage is transmitting data via some type of RF and as a previous comment indicated it is likely highly directional, so flying through that concentrated signal area can kill your comms completely. This is also the concept behind intentionally jamming these systems for defensive or other purposes.
Strong transmitters are typically located on bridges, water towers, smoke stacks and other infrastructure we like to fly near and is something to be aware of. It can be a constant signal, or intermittently used, so one trip may show no issues and another might show interference similar to this.
Perhaps the people who operate the stream gage will tell you what the spectrum used is that it communicates on and you can compare it to that used by the drones control system.
Bottom line: beware of RF energy, it can brick your UAV.
Strong transmitters are typically located on bridges, water towers, smoke stacks and other infrastructure we like to fly near and is something to be aware of. It can be a constant signal, or intermittently used, so one trip may show no issues and another might show interference similar to this.
Perhaps the people who operate the stream gage will tell you what the spectrum used is that it communicates on and you can compare it to that used by the drones control system.
Bottom line: beware of RF energy, it can brick your UAV.
Yeah ... your throttle input & the ascend is clearly seen in the log but that will not change the fact that the IMU says your drone is pointing south west & your video shows it pointing south east when the incident starts.
Ultrasonic sound & WiFi interference will not affect your IMU at all ... as said earlier, that will at most affect the connection between your RC & the drone.
When it comes to magnetic interference up on height during the flight ... it will not immediately make the IMU change it's yaw direction, this as it isn't the compass (which will be affected immediately) that handles the flight, the compass only initiate the IMUYaw during power on... after that the IMU takes over by means of it's gyros & accelerometers. If staying a long time in magnetic interference during flight the compass will slowly, together with other sensors feed in corrections regarding yaw to the IMU ... but that isn't anything that happens from one second to another.
Feel free to post up more TXT logs if you have experienced this during several flights ... but note that those will not give anything extra if you haven't power cycled the drone in between or if you have powered on the drone in the same place that you did in the flight you've already posted.
What we really need is access to a DAT log from the goggles ... that will contain all raw sensor data we need to be able to say anything more.
Going further with what we have right now will open up for a huge array of speculative reasons which we can't find any support for through the TXT log ... everything from suspicious exposure changes, storm winds, bird strikes, various electrical gremlins over to meteorite hits & small green men.
That's only half correct ... signal interference will only affect the control link & at most make the drone failsafe & initiate RTH. We have never ever seen interference mess up the IMU ... if you could point me to an example where a drone have developed a yaw error due to signal interference I would be very interested.
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Mike Mas
Well-Known Member
I suggest you do three things:
Re-calibrate the Compass
Re-calibrate the IMU
Fly at a different location!
Been flying these things for a while and every now and then, they do stupid things which seldom reoccur.
Mike
Re-calibrate the Compass
Re-calibrate the IMU
Fly at a different location!
Been flying these things for a while and every now and then, they do stupid things which seldom reoccur.
Mike
The "stuck" ultrasonic altitude you are seeing isn't real. When the ultrasonic signal is invalid the .txt log file will continue to report the last valid datum. Here is ultrasonic altitude from a flight of my FPV. The top graph shows the .txt log and the bottom shows the .DAT log file. At 366 secs the ultrasonic altitude becomes invalid as can be seen in the .DAT log file. But, the .txt log file continues to report the last valid value.
Have you had any success retrieving the .DAT from the DJI goggles? It's very likely the .DAT will reveal that the launch site was geomagnetically distorted which was the cause of this incident.
Regarding the supposition that the FPV suffered some kind of disruption caused by either exogenous RF energy, internal power glitch, etc. These disruptions would lead to data that is physically impossible or otherwise unbelievable. None of that happened here.
@buwalker
The magnetic yaw error makes sense and is the simplest reason for the flight; but it's worth noting electronic events in power delivery don't always yield total "unbelievable" garbage. Many times, in my experience, errors can creep in that alter the data in minor but significant ways. Faults don't always lead to total corruption. But here again, the OP has now clarified the video change was something he did post recording. So the system wide factor I was following isn't real.
The magnetic yaw error makes sense and is the simplest reason for the flight; but it's worth noting electronic events in power delivery don't always yield total "unbelievable" garbage. Many times, in my experience, errors can creep in that alter the data in minor but significant ways. Faults don't always lead to total corruption. But here again, the OP has now clarified the video change was something he did post recording. So the system wide factor I was following isn't real.
I see where you were advised that the correct .DAT has a label that ends with FLY019.DAT. That would be correct if this were not an FPV. In this case the file name looks like
FLYnnn-019-xxxxxxxxxxxxxxx.DAT
@slup
@BudWalker
Can't get the included FLY098-019-20220227130242.DAT to open up in CsvView ... is it encrypted nowadays or have the OP retrieved the wrong DAT?
What I read on the net is that these .dat files are encrypted and the other .txt files are the best to use. I have contacted DJI support as well. Now they asked the serial number of the DJI FPV .. again I have to wait until the evening because it is not at the offfice : )
I've been unable to verify that the FPV Goggle .DAT is encrypted. I've tested using different versions of the Fly App (both iOS/iTunes and Android) and FPV firmware. An unencrypted Goggle .DAT can be obtained if the correct retrieval method (found in .DAT available) is used.
In this case it appears that @RobbieRocker used DJI Assistant 2 to retrieve the .DAT from the goggles. Is this correct? If so, then please follow the instructions in
.DAT available
Specifically, the log files need to be first transferred from the Goggles to the Fly App and then to a PC.
@Kilrah
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