Yesterday I prepared for a flight over some fields, and powered on the drone in the backyard, as I have many times before. The only difference this time was it was about 3 feet from a metal lawn tractor. It went tihrough the warm up cycles, a brief message "No GPS" flashed, it acquired enough satellites, updated the home point, and said "Ready for takeoff". I started the motors.
Only problem was, I noticed the rear LEDs flashing red. Everything else seemed normal. I decided to launch just about 3 feet as I thought perhaps the downward sensor was blocked from the tree stump it was sitting on. But the LEDs continued flashing red. I tried a landing and second takeoff to 3 feet, but nothing changed. SO I abandoned the flight and powered down.
Going to the manual, it seems to indicate I had an IMU error. Never had that before. I don't think it would have prevented me from flying, but I wonder if I might have been one of the "flyaway stories" had I continued?? It makes me wonder if noticing the LEDs flashing red was what saved me, and if that is why others have had flyaways. It would be possible to fail to notice that, or simply ignore it.
I'm also curious as to whether the proximity of the metal tractor (3 feet to the side) would have caused the error. I have launched from close to my car before, and seen videos of people launching from on top of their car sunroof. I know if you have some steel underneath the drone in reinforced concrete for example it can cause issues, but thought that was with the compass, not the IMU.
Anyway, I moved the tractor and tried again this morning, and everything went off without a hitch - alternating green and yellow on the rear status LEDs at takeoff. I did not perform an IMU calibration first as it didn't ask me to. Two flights completed AOK.
Shouldn't DJI offer more of a warning than just the flashing red LEDs if the IMU is corrupted. Seems like a critical error. Perhaps, either place a warning on the controller screen, or prevent takeoff until recalibrated?
Only problem was, I noticed the rear LEDs flashing red. Everything else seemed normal. I decided to launch just about 3 feet as I thought perhaps the downward sensor was blocked from the tree stump it was sitting on. But the LEDs continued flashing red. I tried a landing and second takeoff to 3 feet, but nothing changed. SO I abandoned the flight and powered down.
Going to the manual, it seems to indicate I had an IMU error. Never had that before. I don't think it would have prevented me from flying, but I wonder if I might have been one of the "flyaway stories" had I continued?? It makes me wonder if noticing the LEDs flashing red was what saved me, and if that is why others have had flyaways. It would be possible to fail to notice that, or simply ignore it.
I'm also curious as to whether the proximity of the metal tractor (3 feet to the side) would have caused the error. I have launched from close to my car before, and seen videos of people launching from on top of their car sunroof. I know if you have some steel underneath the drone in reinforced concrete for example it can cause issues, but thought that was with the compass, not the IMU.
Anyway, I moved the tractor and tried again this morning, and everything went off without a hitch - alternating green and yellow on the rear status LEDs at takeoff. I did not perform an IMU calibration first as it didn't ask me to. Two flights completed AOK.
Shouldn't DJI offer more of a warning than just the flashing red LEDs if the IMU is corrupted. Seems like a critical error. Perhaps, either place a warning on the controller screen, or prevent takeoff until recalibrated?
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