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Pilot error caused my crash. But Litchi collision avoidance helped?

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Flying and adjusting a waypoint route. First four times, worked fine, came in about a meter under a branch. Fifth time, came in about a meter high. Why did I not stop when I saw that? Pilot error. Thought it would interpolate height down to the next waypoint. When Litchi saw that the MP was heading for a branch, it stopped about a meter out. But then it started forward every second or so in 20-30cm nudges. I was slow to hit the pause, and by the time I did, the MP was in the tree. Fell 10', lost a leg, maybe a gimbal.

So...

(1) Yes, of course, then fundamental responsibility is mine. When I saw the MP coming in high, I should have stopped the flight and gone and read up on GPS/INS accuracy. What's a good rule of thumb for how much clearance to observe in wayponit flying?

(2) Litchi CA seems shakier than DJI Go. I had extensively tested DJI Go, and it really didn't want the GP to hit things. Vs the Litchi, which seemed to be playing chicken w/ the tree. I should mention that there was no wind so the branch was stationary. Is there any way to make Litchi CA smarter? There don't seem to be any settings, other than Collision Avoidance On/Off (it was on) and Active Collision Avoidance On/Off (it was off).
 

Tbredhed

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I might be wrong, but it seems me that the AC did not want to go forward but Litchi kept pushing it until it came into collision with the branch.
 

sar104

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Well... crap. Thanks. What's the best way for me to try to read my .DAT file to figure out what happened at the end? Can you point me towards the right self-help?

You can try to retrieve the DAT file from the aircraft - that may or may not work, depending on the aircraft version and where it stored that particular DAT:

How to retrieve a V3 .DAT File from the AC
 
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You can try to retrieve the DAT file from the aircraft - that may or may not work, depending on the aircraft version and where it stored that particular DAT:

How to retrieve a V3 .DAT File from the AC

I have the .DAT from where DJIA2 allowed me to see the directory of .DAT files. But I don't know what to do with it now that I have it. The doc you sent suggests using CsvView, and in fact I was able to install CsvView and load my .DAT. Now I am at the limit of my competance. Any good guides on how to poke around in CsvView?
 
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I might be wrong, but it seems me that the AC did not want to go forward but Litchi kept pushing it until it came into collision with the branch.

Attached I've zipped a few seconds as it goes into the trees. It's still totally in waypoint autonomous mode. You can *see* it stop, think, and then start "nudging" itself into the branches.
 

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  • crash-short.zip
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sar104

Dic mihi solum facta, domina.
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I have the .DAT from where DJIA2 allowed me to see the directory of .DAT files. But I don't know what to do with it now that I have it. The doc you sent suggests using CsvView, and in fact I was able to install CsvView and load my .DAT. Now I am at the limit of my competance. Any good guides on how to poke around in CsvView?

If you want anyone else to look at it then you will need to upload the DAT file to Dropbox or similar, and post a link. Without seeing the file it's impossible to say what was happening.
 
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If you want anyone else to look at it then you will need to upload the DAT file to Dropbox or similar, and post a link. Without seeing the file it's impossible to say what was happening.

I wasn't going to assume anyone else would be willing to look at it, but if you'd be willing I'd sure appreciate it: FLY027.DAT.

My question is really around what happened in the final 10 seconds or so- why did it keep going forward, and did it perform a RTH or something similar at the very end, as it shot up further into the tree in the last 2-3 seconds. Did I successfully cancel the autonomous flight but then make a (further) mistake myself?
 

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