Really strange crash

[brsoft]

So guys, today i experienced really strange crash.
I was taking some test pics and video in perfect weather condition, when out of nowhere, the mini just fell from about 3 m. near me.
Here is the video: 32.64 MB file on MEGA
I'm attaching the logs too.

It looks like bird strike, but there was no birds at all
I'm really confused.

 

[Meta4]

I'm attaching the logs too.
It looks like bird strike, but there was no birds at all

Your drone was flying normally for 12 mintues, lots of battery, no indications of any problem.
Toward the end of the flight you left it hovering for 10 seconds and the data ends suddenly with the drone 8.5 metres above ground.
There's no indication that the drone hit something or was hit by something.
This suggests a sudden, total power loss, possibly caused by a hardware failure or battery being dislodged.

 

[Prismatic]

Your drone was flying normally for 12 mintues, lots of battery, no indications of any problem.
Toward the end of the flight you left it hovering for 10 seconds and the data ends suddenly with the drone 8.5 metres above ground.
There's no indication that the drone hit something or was hit by something.
This suggests a sudden, total power loss, possibly caused by a hardware failure or battery being dislodged.

I can't say if the video and log files are from the same flight, but the video is definitely not from a flight that experienced a sudden, total loss of power; the drone continues recording video during and after the in-flight failure.

 

[Meta4]

I can't say if the video and log files are from the same flight, but the video is definitely not from a flight that experienced a sudden, total loss of power; the drone continues recording video during and after the in-flight failure.

I usually don't check crash video as it can be confusing and doesn't show more than the data does.
But this one is different as it shows that power to the camera wasn't lost.
But the data just stops at 761.7 seconds with the drone still hovering 8.5 ft in the air.

There's obviously been some kind of hardware failure that's caused a loss of signal and power to at least one of the motors.

 

[brsoft]

Hello,
the drone fell on the grass, but with the battery inside, the propellers were still spinning.
Unfortunately, i can't trust Mini anymore

 

[MAvic_South_Oz]

Perhaps some more in depth analysis can be made by @Meta4, and @slup and / or @sar104 might have some input.
It sounds like this just may be a failure that will see DJI replace your mini, depends on warranty status and the likes too.
Maybe post up how long you've had it and warranty that may still apply etc, sometimes they may cover catastrophic failure outside warranty too, depends on what it is.

 

[slup]

-Camera recording doesn't stop = no full system power loss.

-According to the clip the AC pitches cleanly straight up ... then back forward to full upside down with a slight CW rotation = would point to that something happens out to the rear right side (which is a CCW torquing side).

-The .DAT log ends (without reveling anything...) = the system lost power to a component that regulate the .DAT recording.

-The .TXT log ends = all or some motors stop.

-According to the clip all or some motors rotate when the AC is upside down on ground and the .TXT log indicate a logging restart ..?


All these observations together can possibly indicate a partly power loss in the system out to the rear motor side ... if all 4 motors were spinning on ground it should mean that the power returned which can explain the end in the .TXT log.

I suspect that this was a power glitch to the ESC's to both or the right rear motors/motor ... but can't base that on anything in the logs so purely speculative. But this should be something that DJI should cover if the warranty still is active.

Did all 4 motors spin on ground & is there any later created .DAT log in your mobile device (FLY026.DAT)?

 

[brsoft]

Hi, there is fly026.dat, I'm attaching it. I'm not sure if all 4 motors were spinning on the ground, because I used emergency shut down. The left back arm was folded, battery cover was opened, but battery was still in.

 

[BudWalker]

FLY026 appears to have been recorded very soon after FLY025. Unfortunately, the GPS hadn't began so it's not possible to determine when FLY026 started. But, looking at the battery temp, voltage, percentage and temperature data it's clear that FLY026 started very soon after FLY025 ended.

Was it a abrupt power loss followed by power on and then reboot? Or was it a reboot without losing power? The IMU calculations started over as can be seen by looking at the IMU:cnt data which is initialized to 0 when the FC starts the IMU processing. The same is true of the Battery_Info calculations where it can be seen that BatDynCnt is reinitialized. These reinitializations suggest that it was a power loss that caused the reboot.

However, the vision system process was not reinitialized as can be seen by the VIO:cnt and VIO:timestamp data. Here is the end of FLY025

and the beginning of FLY026


From this it's seems clear that power was not interrupted - the MM rebooted itself.

 

[slup]

If no deliberate power cycle was made immediately after the crash I suspect that FLY026.DAT belongs to the same flight but where started after the Mini had "rebooted" ... the first .DAT is approx 13min long & adding that to the FLY025.DAT name time stamp gives the name time stamp of FLY026.DAT.

If still within warranty DJI will certainly take this ...

 

[brsoft]

Thank you all

 

[MAvic_South_Oz]

Thank you all

..
Good luck with DJI, they probably won't tell you what they find (if anything more can be determined by them), but please post back here how it works out with them.
Good to know if they will stand by such failures.

And great collaborative analysis by the 3 members.

 

[brsoft]

..
Good luck with DJI, they probably won't tell you what they find (if anything more can be determined by them), but please post back here how it works out with them.
Good to know if they will stand by such failures.

And great collaborative analysis by the 3 members.

In fact, the drone has no visible damage, so I will try to fly with it, but with extreme caution. I'll keep you informed about its behavior.

Have a nice day

 

[brsoft]

UPDATE:
Today i had intention to fly but there was another surprise.
I turned on the Mini and started the DJI fly app. I was waiting for GPS lock, when suddenly the drone restarted by itself. I received a message "Aircraft not connected to RC", the drone indicator started to blinking red and LED1 + LED4 ON. I couldn't turn it off through the power button, so i needed to remove the battery. The mini was a bit hot. Curiously, the camera worked all the time. I'm attaching a video link.

Video Unavailable

This video is unavailable.

streamable.com

Does anybody know what led1 + led4 ON means? I couldn't find anything in manual.

10 days ago, the mini crashed out of nowhere. Restart during flight? ?

 

[brsoft]

UPDATE 2:
"Flight control system error" + solid red drone light !?! Come on DJI.

 

[slup]

UPDATE 2:
"Flight control system error" + solid red drone light !?! Come on DJI.

Really seems like your strategy "...so I will try to fly with it" isn't a success story. Time to send it in to a DJI repair facility.

 

[brsoft]

Sure, but i'm curious about the problem

 

[cybervet]

At 17 sec into the video something passes in front of the drone, looks like a bird.

 

[Meta4]

At 17 sec into the video something passes in front of the drone, looks like a bird.

It's a fly that's quite close to the camera.
For a bird to be so out of focus, it would take up most of the screen.

 

[brsoft]

Definitely that was some kind of insect. There were a lot of them that day.