Today I almost lost control of my Mavic Pro. I'll try to write down as much as I could remember, even though I don't know what's relevant and what's not.

I put the drone on an uneven surface, turned it on. The camera was shaky, and there was some drone error status. I didn't pay much attention. After a while, the error status was gone. I used DJI Go app to let it take off. Nothing happened. After a few tries, it took off, but was erratic. The camera view was still shaky. I felt the camera was twitching. The worse thing was that the left stick didn't work. The drone flew up and down and started turning. I admit, as a newbie, I can easily get panic, and at that time I think I should be! I used Home button. It seemed to received the command and flew lower. I can't remember how I managed to let it land but I did.

Then I blamed the uneven take-off surface. I re-calibreated IMU and compass. I restarted the drone, tried an flat and even surface this time. No error messages this time. But it got the same problem again! Left stick not working, twitching camera...

I dared to try it the third time. Turned off everything and started it. It worked. And it works afterward.

My questions. I hope someone can explain what was causing it and what I should avoid. How often and when should I calibrate IMU?
Most importantly, if I lose control of my drone again, what should I do? What's the emergency plan?

I'm sorry for your scare, what is your email and I can take a look at your flight.
Go into the flight records and sync your flights to the DJI cloud.
Had you done a compass calibration before, or an IMU calibration?
The IMU should not be calibrated unless there are error messages and telling you the IMU needs calibrating.
In the Advanced Settings of the MC Settings page you can see your compass and IMU status

Can you also confirm a few things,

Were the batteries fully charged ?
Did you perform the FW update when you received it ?
Did you calibrate the compass outside and far away from any metal, also no metal on your person or smart devices like phones or Apple Watch ?
When you say uneven surface what do you mean, where were you ? on building, grass, concrete, Pier ect ?


What worries me is you did not pay much attention to the initial errors, do not take off with any errors, even if they go, stop investigate and understand what is happening.

Ken will get you sorted but would be interested in these questions specifically and could you also post a video of the flight log play back with the controles in view

Scary.  Following.

  

Yes this scares me too
szuo, can you please cooperate with DJI to get clarity(get log files out of your mavic and put them online for DJI to analyse)  as soon as possible on how this can happen, it actually is in interest of everybody that is having a Mavic and DJI that might need to check for some problems within the software.

  

Thanks for your prompt response, DJI-Ken. I'll PM you later about flight records and screenshots.

To answer the questions from you guys
Yes, I had calibrated IMU and compass before the first flight.
The battery was about half-full. I made a few more short flights after I "fixed" it.
Yes, I updated firmware the first time I turned on the drone.

"Did you calibrate the compass outside and far away from any metal, also no metal on your person or smart devices like phones or Apple Watch ?"
I did it in a park. But well, obviously my phone was with me because it's part of the controller. iPhone has metal back cover.

"When you say uneven surface what do you mean, where were you ? on building, grass, concrete, Pier ect ?"
It was unevenly paved brick road. Also a bit wet after rain, if that matters.

szuo Posted at 2016-10-30 14:29
Thanks for your prompt response, DJI-Ken. I'll PM you later about flight records and screenshots.

T ...

Firstly it is a real mistake to take off on half battery, the uneven ground should not be a problem, IMU calibrations should be done on a completely flat surface you can use a sprit level to check,
When your aircraft was flying erratically, you should have landed and went somewhere to check what was happening, you can do this in dji go app by replaying flight in flight history page ,and at the bottom of that screen you will be able to see the virtual movements of the sticks, it will give you an idea of what you called erratic up down movements,
You should maybe put a bit of time into preparation before you go out flying, you don't have to calibrate everything, but you can check IMU in the app , you don't need to do it for every flight but check it often, gimbal calibration if your doing photography or video , compass only needs to be done in the location once for your first flight if you same place you shouldn't have to do it again unless prompted, if you are travelling some distance it's always been advised to calibrate compass for that location.
I will say again don't take off without full battery , if you finish a mission on half battery change battery or recharge to full if you only have one.
If you have dji care you shouldn't be afraid to go back out and try again but start with flying aircraft 10 feet of the ground let it hover to make sure nothing is showing up.
If it's a malfunction because of dji then they have to sort through warranty if you have care plan then your covered..

I am curious if we are all missing a step... Should we all be doing a manditory power cycle of the drone and remore after a firmware upgrade? I wonder if some are not doing this. It only occurs to me because the original post above saws all is fine after a restart. Many get alerted to an update when they are about to fly, do the uodate, and then take off.

dana5 Posted at 2016-10-30 15:37
I am curious if we are all missing a step... Should we all be doing a manditory power cycle of the d ...

Well can't take off until firmwear has been updated, if all calibrations are done firmware shouldn't change them , if it did you would be prompted to recal, I do think people are being a bit careless about preparing the drone before flying, I'm just waiting to hear someone say they hit the RTH button the aircraft drops to fifteen feet and crashes down on top of trees. Lol

Sigh, it seems I can't PM other people on the forum. Here're the screenshots you asked. I've sync'd my flight records to cloud from DJI Go app. (Does it mean DJI team could read them? That's totally fine. But I don't like to expose too much privacy on public forums.)

Szuo, please report your incident in this topic http://forum.dji.com/thread-67927-1-1.html
DJI is following this topic

hallmark007 Posted at 2016-10-30 23:18
Firstly it is a real mistake to take off on half battery, the uneven ground should not be a proble ...

Hi !
Could you elaborate why its a problem to takeoff with 50% batteries ?
I am new to DJI but my APM / Pixhawks couldnt care less so whats the Problem here ?
(Well unless you expect the full flight time but at least emergency land should kick in)

Thanks for sharing the info,

Nils

nils_heidorn Posted at 2016-10-30 20:25
Hi !
Could you elaborate why its a problem to takeoff with 50% batteries ?
I am new to DJI but my  ...

Ok so take off will use a certain amount of battery warming up, you will also have set critical battery at say 15% which would be normal some set it at 20% so you have about 20%  or less for flying if you to far away and your drone thinks it doesn't have enough battery to come home it will just land, if at critical battery RTH will kick in , if anything happens like your drone is coming home into a headwind, you are trusting it to have made allowances for this, this is always a risk, again it will land wherever it thinks it can before it runs out of battery, easiest way to allow for this not to happen is always have plenty of battery, so the general if your flying a mission always take of with a full battery.
If your just checking something that's only gonna take five minutes and your flying at 10 feet well obviously that is fine.
This guy was out for a Saturday afternoon flying with about 6/7 minutes battery.
Batteries can also be temperamental and go from 50 to 20% very quickly especially if your flying into head wind ,
It's always better to be safe than sorry.

hallmark007 Posted at 2016-10-31 04:59
Ok so take off will use a certain amount of battery warming up, you will also have set critical ba ...

Okay, i am aware of those caveats so i feel safe again, i thought there was some DJI-weirdness :-)

Is the DJI % based on Voltage purely?
(hopefully with temperature & current compensation)

On APM / Pixhawk i have the OPTION to use Wh. This of course FORCES you to check your batteries and care for saftety margins yourself considering a lot of stuff (like temperature...).

Greetings,

Nils

hallmark007 Posted at 2016-10-31 02:18
Firstly it is a real mistake to take off on half battery, the uneven ground should not be a proble ...

What a load of rubbish.

Taking off with half battery is fine, as long as you don't exceed the limitations of the drone, keep an eye on the voltage per cell, and plan your route as to leave sufficient power to make the journey.

The above comes with experience, and the best way to learn is by doing.

Scaremongers with pitch forks on this forum

psblah Posted at 2016-10-31 05:28
What a load of rubbish.

Taking off with half battery is fine, as long as you don't exceed the lim ...

Hey, he explained it nicely enough.
With selfie drones like the Mavic you really cannot know how little knowledge users will have.
I am fine but others may feel forced to think about what theyre doing and thats never wrong...

My 2 Eurocents...

Nils

psblah Posted at 2016-10-30 16:28
What a load of rubbish.

Taking off with half battery is fine, as long as you don't exceed the lim ...

No he's right.  It's recommended you take off with a full battery.  You can search the forums and find hundreds of threads on the topic.  I know this is a big deal with the Inspire, I don't know why it would be any different with the Mavic.

method007 Posted at 2016-10-31 05:34
No he's right.  It's recommended you take off with a full battery.  You can search the forums and  ...

Okay, now you sound like there is magic involved again.
Just because "everybody says it" does not make it more sensible.
Is there more to it then halmark007 elaborated ?
I mean its a battery and a Copter that uses energy, hardly rocketscience IF you are a bit careful.
Or IS there some special DJI-weirdness ?
Oh i WISHED i could get a Mavic with Pixhawk :-)

Nils

If taking off with a full battery is a given then landing with at 50% is also the truth.
Both totaly stupid and holds no merit in reality.

psblah Posted at 2016-10-30 21:28
What a load of rubbish.

Taking off with half battery is fine, as long as you don't exceed the lim ...

Edited for offensive content.

nils_heidorn Posted at 2016-10-30 21:45
Okay, now you sound like there is magic involved again.
Just because "everybody says it" does not  ...

Well the first time you have a crash and you put your logs up here first question people will ask you is why did you take of with just 50 % battery I look forward to the day.

psblah Posted at 2016-10-30 21:28
What a load of rubbish.

Taking off with half battery is fine, as long as you don't exceed the lim ...

Manual pre flight checklist page 49 go read it if you have anything left between your ears, there is always a pudding on here who thinks he knows everything.

nils_heidorn Posted at 2016-10-30 21:14
Okay, i am aware of those caveats so i feel safe again, i thought there was some DJI-weirdness :-) ...

Manual page 49 pre flight check list you might think they included for fun..

nils_heidorn Posted at 2016-10-30 21:45
Okay, now you sound like there is magic involved again.
Just because "everybody says it" does not  ...

Thats nothing, once i went out with my iphone 6 with only 45% battery remaining!
Everyone was telling me not to, and I read loads of chats about it on forums saying never do it, but I like to live dangerously, so I did it anyway!

Repsolkid Posted at 2016-10-30 22:12
Thats nothing, once i went out with my iphone 6 with only 45% battery remaining!
Everyone was tell ...

It is sad how quickly almost every thread I read goes off topic and ends up with people bickering. I can see why alternative forums end up being preferred - there's a nastiness here and the mods would do well to stamp on it.
(That was not aimed at you though Repsolkid!)

davcom1 Posted at 2016-10-30 22:22
It is sad how quickly almost every thread I read goes off topic and ends up with people bickering.  ...

tbh I have only been posting here a while, but already I have noticed that there are a few regular posters that seem to be very condescending to those peeps that are new to the drone world.
They answer them like they are talking to 4 year olds.

New droners are only new to the hobby not to life, so talking to them like they are idiots only makes the responder look like one.
This 50% battery bullshit is a prime example. If you were going to drive 100 miles in your car and only had 50 miles in the tank, you wouldn't do it, so to try and tell people they shouldn't take off with 50% battery is treating them like kids that don't have the brain to work that out themselves.
In my view it's distraction away from the real issues here, and that is poor product launch with some major issues that need addressing.

hallmark007 Posted at 2016-10-31 09:09
Manual page 49 pre flight check list you might think they included for fun..

Why stop at 5 replies? Keep going mate, I have a feeling I'm not going to get much from you...

Taking off at 50% is not a problem, flying outside the limits of the drone is, and if you can't ascertain what that is, I wonder how you've made it this far....

hallmark007 Posted at 2016-10-31 05:56
A fool and his drone are easily parted . It's idiots like you that get beginners into trouble, you ...

this is a bit like nanny-governance but given the amount of new users are involved, I guess that's warranted.

psblah Posted at 2016-10-30 22:40
Why stop at 5 replies? Keep going mate, I have a feeling I'm not going to get much from you...

Ta ...

These are beginners first thing they're asked to do is read the Manual, but you think they should skip the manual and do it your way, there's always someone who knows much more than everyone else.
Now stop trolling me.

hallmark007 Posted at 2016-10-31 02:18
Firstly it is a real mistake to take off on half battery, the uneven ground should not be a proble ...

well that is exactly what he did, noticed the error and tried to land it manually, he couldnt then he used the Return home button.

He did all the calibration required.

hallmark007 Posted at 2016-10-31 09:51
These are beginners first thing they're asked to do is read the Manual, but you think they should  ...

So it's up to you to determine who is a beginner and must only fly over 50%?
When did you become high and mighty? And you condescendingly say I claim to know more than everyone else while preaching to any random on the internet it's a mistake to fly over 50% battery!

*edited for offensive content.

Repsolkid Posted at 2016-10-30 22:38
tbh I have only been posting here a while, but already I have noticed that there are a few regular ...

Sorry I was asked why not take off with only 50% battery, I gave the reasons it's not condescending, first guy post reads he was going out to fly on a Saturday afternoon, now he said he was a complete beginner, and I explained the first thing he did wrong was taking off for a flight with 50% battery, if you have an aircraft and  or when you do you will find you will nearly always land with 30% or more and if you go on to P4 or inspire forum they will always recommend from experience doing this, they will always recommend when going out flying to use fully charged batteries, and when you see on this forum people crashing and logs produced showing take off battery at 50 %  it will be the first thing mods will bring up,because like you not everyone has this common sense, give it time you will remember this chat.
I only answered the question I was asked I was not rude, and if people don't like the answer they shouldn't ask the question, I was rude to one guy who was advocating you will learn more taking of and flying with 50% battery and this way you will learn more doing it this way ,and it was such a silly thing to say, his opening comment to me was rude , but as you say it's common sense , then why bother putting it in the manual, page 49 pre check flight,

psblah Posted at 2016-10-30 23:08
So it's up to you to determine who is a beginner and must only fly over 50%?
When did you become h ...

No getting through to you ITS IN THE MANUAL READ IT,  but maybe your advice to beginners is don't bother with the manual,

psblah Posted at 2016-10-30 23:08
So it's up to you to determine who is a beginner and must only fly over 50%?
When did you become h ...

You also need to read the PO post, I ADMIT IM A NEWBIE I EASILY GET PANICKED, his words
first question from Mad Angler 1 a very experience pilot , WERE THE BATTERIES CHARGED,
But you know a better way to teach people..

I would love to know the relevance of amount of battery charge to the OP's problem though? Sure, it might be something for them to consider if planning 27* mins of flying but are we seriously saying that the camera shaking and no left stick control are even remotely related to battery charge? I personally don't have a problem with the logic of making sure you remember to use full batteries etc. and worth referring the OP to the pre-flight checks in the manual ... I just don't see it as pertinent to the initial post and therefore led to the off-topic arguing.

"Hello, is that the AA/RAC? My car lights won't work and the steering does nothing."... "I see sir, well, do you have a full tank of fuel?"

And hallmark - "if people don't like the answer, they shouldn't ask the question"? How do you know what the answer is going to be? lol

hallmark007 Posted at 2016-10-31 10:29
No getting through to you ITS IN THE MANUAL READ IT,  but maybe your advice to beginners is don't  ...

Using capitals to signify shouting does not make you any more correct. You obviously didn't grasp this after primary school...

You fail to comprehend the basic message I'm trying to convey to you, taking off at 50% is not the problem, flying outside the limits of the drone is, this is not a difficult thing to learn. If you take off, and land immediately afterwards, there is no difference between doing this at 50% battery and doing this at 100% battery.

Your advice should be teaching this very basic concept to beginners, if that truly is your noble cause here, instead of preaching your unhelpful retorts about the manual and ill-founded logic on battery life.

Anyway, I'm done with you, hopefully others will read what I've written and use their brain all the while you'll sit there, reading your book, wondering why it all went wrong.

psblah Posted at 2016-10-30 23:46
Using capitals to signify shouting does not make you any more correct. You obviously didn't grasp  ...

Shouting but calling someone a dickhead is ok get a grip.
It was because he was a beginner I asked about the battery as did mad angler before me , do you think that was a coincidence, or do you think your attack applies to mad angler as well.
And just as all dji moderators here will advocate reading the manual, which is the best advice I feel and they do especially to beginners.
You obviously have a different and much better way to learn. Off with you.

It's possibly the IMU calibration you did initially was not correct hens error and behaviour.

Did you follow the process correctly ?

Have you flown it since and how is it now.

davcom1 Posted at 2016-10-30 23:45
I would love to know the relevance of amount of battery charge to the OP's problem though? Sure, it  ...

Well if you look at mad angler post first question asked were the batteries fully charged ,a mere coincidence I don't think so.
If you then look at the answer I gave it was not condescending, I mentioned the battery but the bulk of my answer was regarding imu calibration and where and how it was done,
Next someone decided to ask me what was the  reason for saying to him he should start flying on full battery, and I gave him my answer which would be the same answer given by most maybe not here because it's new forum,
My answer was in no way condescending or rude it's there if you care to read that and equally my first post to PO,
Then the maverick steps in and says I had no right to advise , which when you read the post you will see that's all I done,
He said the best way to learn was to tell the guy to take off and learn to fly with 50% battery and that he would learn much quicker, but he chose his opening gambit to be rude and condescending,
I also see same guy just arrived today knows everything but has a newbie account and decides to attack me when he was not even involved his only contribution to that thread was not to help PO but to attack me, I've been around to long for that.

Following, thanks for sharing