Question about a crash... a little help please...

[BudWalker]

OK, I got it after re-launching CsvView. This is a really useful feature !

Actually, it was the act of re-loading the .txt that caused ImuCalcs to work.

 

[Deleted member 103366]

I have Android, latest version I guess. I think autosync is enabled indeed. I will turn it off from now on..

It has a slim chance of producing anything useful or relevant but since you have nothing to lose, on the Android device open the "my files" app and do a search for ".DAT". If by chance it does find anything useful bluetooth it across to your PC

 

[boblui]

At first I thought it was just the drone misrecognizing the tree as the OP but now I know I was wrong.

Slup has done a very good analysis on the cause of the crash. Basically, the IMU suddenly went crazy and told the flight controller that the craft was making a sharp right turn. This is very different from the GPS information which indicated that the craft was going straight forward. From the video, the GPS was correct.

At that moment the flight controller needed to make a very quick decision on which to trust, the IMU or the GPS ? Very clearly the GPS was chosen because the flight controller did not react by attempting to correct the direction of the craft by turning sharply to the opposition direction ( left ).

However, the sensor fusion algorithm still gave a very small weight to the IMU's output so the final judgement of the flight controller was that the craft was making a shallow turn to the right. The logical reaction was to correct by commanding the craft to make a shallow turn to the left and that's what the video has shown. Unfortunately, a tree was standing there. As the IMU has malfunctioned, we cannot expect the APAS system to work to avoid the obstcale.

The IMU of the craft is clearly faulty. I doubt very much if calibration can fix it. Suggest to send it back to DJI for a replacement or similar incidents will happen again.

 

[srnolten]

Thanks again for everybody's input. I still have to testfly it, but we have bad weather in The Netherlands. I Calibrated the IMU and hope this will fix things.
I am going to fly carefully from now on !

 

[PDX-DroneGuy71]

I noticed the battery voltage dipped from 11v down to 10.65 during this sideways left movement. Afterwards it returned to 10.98. Could have been a momentary voltage issue caused the glitch. Dirty contact could cause this. Not an expert but my EE senses say this is not normal.

 

[srnolten]

Thanks for you reply, I will check the batteries and the drone.

 

[slup]

I noticed the battery voltage dipped from 11v down to 10.65 during this sideways left movement. Afterwards it returned to 10.98. Could have been a momentary voltage issue caused the glitch. Dirty contact could cause this. Not an expert but my EE senses say this is not normal.

Thanks for you reply, I will check the batteries and the drone.

Never bad to check drone & batteries ... but the temporary voltage drop didn't cause this incident, it was only a result of the very rapid heading speed increase just there & the cells was never down to any alarming levels.