Mavic 2 wouldn't land and went berserk on me.

[MavPro72]

Hi all, I'm trying to figure out why my drone wouldn't land on me earlier tonight. I wanted to catch an awesome sunset by the water. So went down a road, which basically is on the coastal waters. So water all around (think of it like a pier) I parked my car at the Dead End. and launched my drone maybe 4 feet behind my car. Anyway as the sun was going down and my battery was getting low, i thought i'd hovver it around above the water to get the last of the sunset reflections. Eventually the battery said critically low, and it said return to home. HOWEVER it wouldn't land.. It hovered around 6ft up from where it was supposed to land. Bleeping like crazy (i'm guessing obstacle but with so much going on, i really don't know) I was getting nervous cos i was worried the battery was going to die any second and my drone dropping from that height would of almost certainly have it end up toast. So i thought maybe grab it, but again everytime i would try and grab it, it would try and get away from me. So i thought maybe put it sport mode to turn off the sensors but it still wasn't happy. It did keep turning on its landing lights as i'd try and grab it, before going up a few feet. Eventually, i managed to get hold of the **** thing, slicing up my hand in the process. And the motors really ramped up. Like to the point it was pulling hard away from me. I was genuinely nervous at this stage. My hand was already sliced up pretty bad with blood dripping everywhere. I was concerned for my eyes more than anything, knowing it was at full power and going beserk, if i let it slip it could go straight into my face. . i also wasn't letting go of the drone, knowing all too well, it was trying to get away and there was too much water in the vicinity. I tried getting the battery out, but with the props spinning up like they were you can't really see them and things getting dark by now, it was kinda hard. Eventually after a min or two fighting the thing, it just calmed down and shut off. THANK BEEP !!! But it would be nice to know WTF Happened, so i can avoid it from happening again. Could it of been cos the light became too low, it didn't know its landing zone ? I could of been because there were barriers around the road to stop cars from going into the water ? Metal armco barriers to be precise. Could that of caused it to flip out ? Plus my car was kinda close. But i've always launched a few feet from behind my car. Anyway, any idea's would be appreciated. Glad its home and well about to check out the awesome footage i will have got from it.

 

[sar104]

Your questions will require at least the txt flight log to answer.

Flight log retrieval and analysis guide

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[MAvic_South_Oz]

Your questions will require at least the txt flight log to answer.

Flight log retrieval and analysis guide

On Paragraphs // Purdue Writing Lab

The Purdue University Online Writing Lab serves writers from around the world and the Purdue University Writing Lab helps writers on Purdue's campus.

owl.purdue.edu

Wrong link below the right one @sar104 ??

 

[MavPro72]

Here's what i could get off the logs. The battery not installed properly is probably after i managed to grab hold of it and with the same hand unclip the clips.

The remaining battery is only enough for RTH. Return home now.
Low Power. Aircraft is returning to the Home Point.
Braking to avoid obstacle RTH: Braking to avoid obstacle
Braking to avoid obstacle
Braking to avoid obstacle
Braking to avoid obstacle
Braking to avoid obstacle
Braking to avoid obstacle The remaining battery is only enough for RTH. Return home now.
Braking to avoid obstacle
Ambient Light too Weak, Vision Positioningobstacle sensing is unavailable.，please ensure safety during the flight
Ambient Light too Weak, Vision Positioningobstacle sensing is unavailable.，please ensure safety during the flight
Ambient Light too Weak, Vision Positioningobstacle sensing is unavailable.，please ensure safety during the flight
Ambient Light too Weak, Vision Positioningobstacle sensing is unavailable.，please ensure safety during the flight
Ambient Light too Weak, Vision Positioningobstacle sensing is unavailable.，please ensure safety during the flight
Ambient Light too Weak, Vision Positioningobstacle sensing is unavailable.，please ensure safety during the flight
Ambient Light too Weak, Vision Positioningobstacle sensing is unavailable.，please ensure safety during the flight
Ambient Light too Weak, Vision Positioningobstacle sensing is unavailable.，please ensure safety during the flight
The remaining battery is only enough for RTH. Return home now.
Gimbal Roll Reached Movement Limit
High wind velocity. Fly with caution and land in a safe place ASAP.
Ambient Light too Weak, Forwardobstacle sensing is unavailable.，please ensure safety during the flight
Critically Low Power. Aircraft Landing
Battery not installed properly. Return to home immediately. Check and re-install battery; Gimbal Roll Reached Movement Limit
Gimbal Roll Reached Movement Limit
High wind velocity. Fly with caution and land in a safe place ASAP.
Gimbal Motor Overloaded. Check if the gimbal clamp is mounted off.

 

[MAvic_South_Oz]

@MavPro72 . . . how's the fingers / hand coming along ?
Not sure about the M2, but turning many DJI aircraft onto their sides stops them instantly.

You can upload that txt file here . . . DJI Flight Log Viewer | Phantom Help
Then post a link here.

The obstacle detected was likely the sun, seeing as you were filming it.
When it went dark the Vision position advisory (and also OA would be same) was due to insufficient light.

Loads of various warnings, the 'Battery not installed properly' one is a great concern.
Possibly you trying to remove it ? But this was before forced landing kicked in.
Gimbal overload was probably your hand interfering with it whilst wrestling with it.

Were you allowing it to land automatically, or manually bring it down with left stick ?

 

[Paul2660]

I believe once you had it in your grip the next step should have been to flip it upside down. It’s my understanding that will stop the rotors.

You can also turn off obstacle avoidance in the go app. It’s the green icon in the upper right of the screen looks like a radar symbol. I usually land with it off.

Paul C

 

[sar104]

Wrong link below the right one @sar104 ??

No - I think that was a very appropriate link...

 

[sar104]

Here's what i could get off the logs. The battery not installed properly is probably after i managed to grab hold of it and with the same hand unclip the clips.

The remaining battery is only enough for RTH. Return home now.
Low Power. Aircraft is returning to the Home Point.
Braking to avoid obstacle RTH: Braking to avoid obstacle
Braking to avoid obstacle
Braking to avoid obstacle
Braking to avoid obstacle
Braking to avoid obstacle
Braking to avoid obstacle The remaining battery is only enough for RTH. Return home now.
Braking to avoid obstacle
Ambient Light too Weak, Vision Positioningobstacle sensing is unavailable.，please ensure safety during the flight
Ambient Light too Weak, Vision Positioningobstacle sensing is unavailable.，please ensure safety during the flight
Ambient Light too Weak, Vision Positioningobstacle sensing is unavailable.，please ensure safety during the flight
Ambient Light too Weak, Vision Positioningobstacle sensing is unavailable.，please ensure safety during the flight
Ambient Light too Weak, Vision Positioningobstacle sensing is unavailable.，please ensure safety during the flight
Ambient Light too Weak, Vision Positioningobstacle sensing is unavailable.，please ensure safety during the flight
Ambient Light too Weak, Vision Positioningobstacle sensing is unavailable.，please ensure safety during the flight
Ambient Light too Weak, Vision Positioningobstacle sensing is unavailable.，please ensure safety during the flight
The remaining battery is only enough for RTH. Return home now.
Gimbal Roll Reached Movement Limit
High wind velocity. Fly with caution and land in a safe place ASAP.
Ambient Light too Weak, Forwardobstacle sensing is unavailable.，please ensure safety during the flight
Critically Low Power. Aircraft Landing
Battery not installed properly. Return to home immediately. Check and re-install battery; Gimbal Roll Reached Movement Limit
Gimbal Roll Reached Movement Limit
High wind velocity. Fly with caution and land in a safe place ASAP.
Gimbal Motor Overloaded. Check if the gimbal clamp is mounted off.

That's definitely strange. It clearly ignored repeated down throttle for a couple of minutes.



The high wind warning was because you grabbed it, and the battery latch errors were due to your attempt to remove it. The reason for the refusal to land is almost certainly related to the ambient light messages, but I don't know why that would prevent landing.

It might be worth a look at the mobile device DAT file (FLY050.DAT) to see if there is anything more definitive there.

 

[MavPro72]

@MavPro72 . . . how's the fingers / hand coming along ?
Not sure about the M2, but turning many DJI aircraft onto their sides stops them instantly.

You can upload that txt file here . . . DJI Flight Log Viewer | Phantom Help
Then post a link here.

The obstacle detected was likely the sun, seeing as you were filming it.
When it went dark the Vision position advisory (and also OA would be same) was due to insufficient light.

Loads of various warnings, the 'Battery not installed properly' one is a great concern.
Possibly you trying to remove it ? But this was before forced landing kicked in.
Gimbal overload was probably your hand interfering with it whilst wrestling with it.

Were you allowing it to land automatically, or manually bring it down with left stick ?

Yeah i was trying to bring it down manually with the left stick, being that i was too close to water on the sides. i was more confident me bringing it down, than it land a few feet away by itself in the water. This was actually the first time i've ever had it try and land itself because the battery voltage becoming critically low. Won't let that happen again. Interesting about turning the craft to the side or upside down stops them instantly. I didn't know this. I think i had it more or less to the side.. Definitely not upside down though. Thing had me worried cos its like handling a chop saw, except you can't see the blades, cos they're spinning like crazy and its just got dark in the last min !

 

[MAvic_South_Oz]

No - I think that was a very appropriate link...

Oh yeah, had another peek at the OP, fair enough

because the battery voltage becoming critically low. Won't let that happen again.

That is a great lesson then.
Typically most pilots will land with min 15 - 20% battery, some more, sort of depends on how far away you might be, if there's any wind about you might have to contend with, etc.
Wind is dangerous for any aircraft, try and take off flying into the wind to your filming destination, and return with the wind, not always possible, but it's a lot safer habit.

The M2 might be different in its behaviour turning to shutdown, have a search here on the forum and Google in general, the official DJI Mavic forum has a lot of info too and comes up a lot in general online searching.

 

[Jet skier]

It sounds kind a like the same with thing that happened with my drone turned out being a fried stick module. Did the display ever say stick error?

 

[sar104]

It sounds kind a like the same with thing that happened with my drone turned out being a fried stick module. Did the display ever say stick error?

It wasn't a stick problem - the throttle commands were received by the aircraft but ignored.

 

[Jet skier]

It wasn't a stick problem - the throttle commands were received by the aircraft but ignored.

Yup that’s exactly what mine would do, My drone went haywire and go all over the place I would say try a stick calibration at a minimum

 

[sar104]

Yup that’s exactly what mine would do, My drone went haywire and go all over the place I would say try a stick calibration at a minimum

That's pointless - you can see the stick input data and it was correct. Calibrating the sticks ensures that the stick outputs are correct - it has no effect on the aircraft behavior in response to those outputs.

 

[Jet skier]

That's pointless - you can see the stick input data and it was correct. Calibrating the sticks ensures that the stick outputs are correct - it has no effect on the aircraft behavior in response to those outputs.

I’m sure you’re right . the behavior of that drone just sounds exactly like what mine did but apparently both had different causes

 

[sar104]

I’m sure you’re right . the behavior of that drone just sounds exactly like what mine did but apparently both had different causes

Was yours refusing to land?

 

[Jet skier]

Was yours refusing to land?

Yes I had to crash my drone into my roof just to get it down so it wouldn’t hit something else or somebody

 

[sar104]

Yes I had to crash my drone into my roof just to get it down so it wouldn’t hit something else or somebody

That doesn't sound like an out-of-calibration stick issue either. Did you check the flight log?

 

[Dave Maine]

The MA is very sticky close to landing. It will refuse to go lower when it is close 1-2 feet from a surface or hand. Holding the left stick down for a couple of seconds will overcome it, and it will land normally. It seems as if it is in response to the sensors.

 

[Jet skier]

That doesn't sound like an out-of-calibration stick issue either. Did you check the flight log?

It was a stick issue, I worked with Dji on what to do I tried a stick Cal in the right stick would not zero outs so I sent the controller to DJI and they said the stick module was fried so they replaced the stick module (both). It works fine now