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Mavic tried to kill me! Please, help reading the logs.

Active Track is military technology . It's just attacking by instinct .
 
At time 402 the ultrasonic height sensor went from 5.4 meters to 0 indicating the Mavic sensed something immediately below it. The response was to speed up to avoid the obstacle. There was no control input at this point.

Is it expected behavior for the Mavic to move forwards to avoid an obstacle? I've never experienced nor heard of that kind of response. I've only ever seen the Mavic ascend to avoid an obstacle below it.
 
Is it expected behavior for the Mavic to move forwards to avoid an obstacle? I've never experienced nor heard of that kind of response. I've only ever seen the Mavic ascend to avoid an obstacle below it.
Yeah, I thought about that. Doesn't make complete sense to me either. I was supposing there might be some subtlety involving being in the Active Track mode. The timing was just too compelling as it was only 0.35 secs from the ultrasonic height going to 0.0 and the horizontal speed starting to increase. I suspect that time interval is even less if motorCommanded speed were looked at in the .DAT
 
Yeah, I thought about that. Doesn't make complete sense to me either. I was supposing there might be some subtlety involving being in the Active Track mode. The timing was just too compelling as it was only 0.35 secs from the ultrasonic height going to 0.0 and the horizontal speed starting to increase. I suspect that time interval is even less if motorCommanded speed were looked at in the .DAT
Hi, thanks for the deep analysis.
I updated the .DAT file with the correct one. I'm not sure if it helps more but from this file I can see that as you said the vpsHeight suddenly goes to "?" which corresponds to 0 in the txt. The strange part is the Pitch between 403 and 405. This actually corresponds to the noise I heard when it was approaching me. It was tilting like crazy from side to side while going forwards (this is not seen in the video because of the gimbal). The main root cause of this behavior is still not clear to me. As you said if vpsHeight suddenly goes to 0 it should try to ascend.

BTW the vpsHeight drops to 0 several times in this log but only the last time the Mavic goes crazy.
 

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Hi, thanks for the deep analysis.
I updated the .DAT file with the correct one. I'm not sure if it helps more but from this file I can see that as you said the vpsHeight suddenly goes to "?" which corresponds to 0 in the txt. The strange part is the Pitch between 403 and 405. This actually corresponds to the noise I heard when it was approaching me. It was tilting like crazy from side to side while going forwards (this is not seen in the video because of the gimbal). The main root cause of this behavior is still not clear to me. As you said if vpsHeight suddenly goes to 0 it should try to ascend.

BTW the vpsHeight drops to 0 several times in this log but only the last time the Mavic goes crazy.
My mistake. That changes everything. I forgot, the .txt uses 0.0 for vpsHeight when the sensor isn't reporting a value. The .DAT conversion represents this undefined state properly.

My analysis is totally bogus. I agree with you. The root cause is unknown. The only thing I can add to what's already known is that the motors started changing at 402.5 and the vpsHeight to stop reporting 0.1 sec later at 402.6. The motors had not yet changed enough to cause any pitch down to occur that might have then caused vpsHeight to stop reporting.
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At 403.7 the pitch was down to -15 and the front sensor started reporting. I'll speculate that's what triggered the obstacle warning.
@JLane
 
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Mavic cannot kill an average sized adult, I'm more worried about getting blinded though. if suddently charging at me and then my eyeballs get struck by prop, will be blinded for sure.

Advise those to consider safety googles like the same when hitting the range.
 
If you notice when watching the video. The distance and altitude displays on screen hardly change a jot as the Mavic is careering towards you. The Mavic must of thought it was virtually stationery.......and was having a blonde moment....what could that point to?
 
If you notice when watching the video. The distance and altitude displays on screen hardly change a jot as the Mavic is careering towards you. The Mavic must of thought it was virtually stationery.......and was having a blonde moment....what could that point to?

All the sensor readouts seem to be working fine. The Home Point was 140m away and almost 90 degrees to the direction of travel, which explains the relatively small changes in the Distance value. The changes in Height values also seem to me to correspond closely with the Mavic's flight.
 
Just prior to the 'attack' your wife came up beside you partially blocking you from the Mavic, this might be what started the problem in the tracking software. If anyone feels brave they could test this theory...
 
Hi all,

I'm pretty new in the forum but I have one very interesting case to share with you which happened 2 days ago with my Mavic.

The Mavic was in Active Track (Profile) mode and suddenly it accelerated towards me and my wife. Luckily it missed us and nobody was hurt. I was able to pull the sticks Up and Backwards which forced the Mavic to stop otherwise it would have crashed into us or in the trees.

Here is the Flight Log (issues occurs around 7th min): Phantom Log Viewer - PhantomHelp.com
Here is the DAT file (updated): FLY055.DAT

Here is the Video from my phone of the actual accident (50s):

I didn't press anything on the remote or in the app, and according to the logs there were 13 satellites and no problems with the battery or compass. However, maybe I missed something in the log which caused this strange behavior. Please, give it a look and let me know what could cause this spontaneous change in the flight of my Mavic.

This was the second battery that day with no issues. I flew it the day after with no issues again but didn't try the Profile mode :D If you are interested, here is the video from the same day before the accident:
And soon I will post a video from the following day skiing with my friends.

Regards,
Dimitar

Love the video. That's what this little guy was made for! :)

As advanced as all these features are I still don't trust them. I just don't like giving up control. I don't really like the obstacle avoidance either. I don't trust any of the fly-around-the-obstacle features because it seems there are too many variables to consider to do it right. Obstacle avoidance also screws up my shots. I like to take skim the ground action shots and I like to slide over and around objects. The obstacle avoidance always halts the Mavic and blows the smooth shot. I'm actually thinking of turning it all off and take my chances.

Z
 
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The sun screwing up RTH was enough to get me to turn off OA. Doing that improves hold-in-place in wind and bumps up non-sport top speed up to just about the sweet spot for distance vs battery consumption. Sounds like a win-win to me.
 
I have been flying for several years three days ago 65° weather sunny I put my phantom four in active mode with in three minutes it took off to the left and smashed into a tree for no apparent reason whatsoever was not weather related pilot related it just went crazy luckily minimal damage and I have read several post in the last year with the same problem


Sent from my iPad using MavicPilots
 
I also own the Mavic and I will never use that mode again ever I don't trust it I just read several issues same problem


Sent from my iPad using MavicPilots
 
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