So I've had my Mavic for two days, and I'm not what you'd call a "talented pilot." On two occasionals I have bumped in to things that caused the Mavic to lose control.

So that's all fine and good, but how can I stop the Mavic from spinning its motors as fast as it can once it's crashed? Both times it spun around upside-down on the ground like a banshee. One of the times it was on pavement and it just kept spinning until all of the props were destroyed.

According to the manual, I believe you can supposedly point the control sticks down and away which activates an emergency shut off, but that didn't happen when I tried. It just kept going for probably 5 seconds, destroying itself.

Is there anything I can do to avoid this? Other than getting better / buying more propellers?

The same way you started it, sticks to the corner.

You need to enable the conbination stick command  to be able to stop motors. By default this option is off preventing to do the CSC during flight. It's in user guide.

I don't think both sticks to the corner will work when Mavic is on its back, for P4 I know procedure is left stick all the way down in right hand corner and same time RTH button is emergency stop

Mooney Posted at 2016-12-1 04:41
The same way you started it, sticks to the corner.

That may not stop motors when it's on its back, it certainly won't stop P4 if it was on its back. There is emergency procedure for shutting down motors I'm not to sure what it is for the Mavic.

hallmark007 Posted at 2016-12-1 10:14
That may not stop motors when it's on its back, it certainly won't stop P4 if it was on its back.  ...

Holy crap, still havent received mine but i was wondering about just that.
I asked for the safety / crash detection ages ago but no DJI person felt that safety is important enough to answer.

Just imagine the Mavic fell into a crowd shredding everything...
Aparently it has no (good) crash detection at all... MAN
Here is what i am refering to:

This one:
http://forum.dji.com/thread-70380-1-1.html

And following:
http://forum.dji.com/thread-70427-1-1.html


That is VERY disapointing for a 2016 product...

Nils

nils.heidorn Posted at 2016-12-1 13:55
Holy crap, still havent received mine but i was wondering about just that.
I asked for the safety  ...

In the manual it says that it will refer to app, I don't know why this is, in P4 and P4Pro it clearly laid out in the manual as I have already described..

hallmark007 Posted at 2016-12-1 14:04
In the manual it says that it will refer to app, I don't know why this is, in P4 and P4Pro it clea ...

Sorry, i am no native english speaker, what do you mean by saying "In the manual it says that it will refer to app" ?
Anyways, it should work automatic and idiotproof and also if Tx lost connection... Just look at my first post how the smallish Bebop can handle it...

Greetings,

Nils

nils.heidorn Posted at 2016-12-1 12:55
Holy crap, still havent received mine but i was wondering about just that.
I asked for the safety  ...

In the UK its illegal to fly above crowds anyway

what if the bird do That by itself?

nils.heidorn Posted at 2016-12-1 14:29
Sorry, i am no native english speaker, what do you mean by saying "In the manual it says that it wi ...

The motors can only be stopped in midair when aircraft detects a critical error, this can only be changed in the app. Page 52 manual..

UK Dave H Posted at 2016-12-1 14:48
In the UK its illegal to fly above crowds anyway

As far as I know U.K. Is the same as Ireland you are permitted to fly over crowds at altitude of 120 meters, it may be lower but no a whole lot..

hallmark007 Posted at 2016-12-1 16:52
The motors can only be stopped in midair when aircraft detects a critical error, this can only be  ...

Thank you.

But i need good crash detection WITHOUT User Interaction...
I dont fly near people but if the Mavic decides to do so itself, i AM talking of unwanted behaviour.

Nils

nils.heidorn Posted at 2016-12-1 17:21
Thank you.

But i need good crash detection WITHOUT User Interaction...

If the steering in your car fails or the brakes in your car fail, your car will not know how to avoid a crash., so you keep it serviced and in good condition, and this is less likely to happen.

This is an unmanned aircraft which doesn't recognize people..

nils.heidorn Posted at 2016-12-1 08:21
Thank you.

But i need good crash detection WITHOUT User Interaction...

How do you anticipate designing that feature?

Would it be an automatic power down when abrupt movement occurs?  Now imagine hitting a branch in a tall tree, instead of attempting to recover it shuts down and falls.

Would it be a proximity sensor shutting down when it nears an object?  Again read tree story.

How about barometric pressure?  Ahh but that's consistently changing and wouldn't be a reliable ground sensor.

GPS can measure altitude, however it becomes less reliable if satellites on the horizon are obstructed.

You could have the system shutdown when there's a voltage spike in a motor, like you would see in a propeller obstruction.  Again . . . read the tree scenario.

You could always  put a big red button on the controller that would be an "emergency shutdown," hit by accident while flying and you'll have a catastrophic ending.


I believe if there was an easy answer/solution DJI would build it into the drone.  In the meantime I focus on using the safety features that prevent the crash.  

We can never be certain what will interuppt a flight, however a complete power down would lead to the destruction of the drone when i review many mishap videos:

hallmark007 Posted at 2016-12-1 17:37
If the steering in your car fails or the brakes in your car fail, your car will not know how to av ...

Please read and may update your knowledge of current active safety features in cars...
Its technically easy and doable. Other manufacturers didfor Drones its not in our hands, the Software fails.

And cars btw have something like Airbags and a load of other measures that decrease risk an maximize safety as automatic, foolproof measures.
This is NOT about good maintenance and experience, i am talking automatic & foolproof.

Nils

nils.heidorn Posted at 2016-12-1 17:44
Please read.
Its technically easy and doable. Other manufacturers didfor Drones its not in our han ...

I can tell you airbags will not help anyone on the outside of a car crash.

Mooney Posted at 2016-12-1 17:43
How do you anticipate designing that feature?

Would it be an automatic power down when abrupt mov ...

Hi !
I dont need guesswork, its implemented in other dronesalready :-)

-1- Stop all motors if angle > 90 degrees, thats not a natural flight position.
2- Stop all motors if otor is blocked (high current, low RPM) or running freely (very low curren tdue to prop loss)

plus maybe

-3- Accelerometer based crash detection ( exceding a gee limit ).

And if te motors are stopped ESC's should actually brake.

All this can be found in lesser drones, this is NOT about the price.
Thats very easy given the Mavics ESC's bidirectional connection, given acc & gyro sensors and a fast CPU.

But YES, when colliding with a tree it COULD leed to motors stop and the Mavic falling down.
(Maybe in somecases it would eover without this, i know that MY Priorityis on safet nevertheless)
And YES it would enable a safety at a crash site.

It can be optional if you have different Priorities, just a single switch, no Rocketscience.

Nils

nils.heidorn Posted at 2016-12-1 08:44
Please read.
Its technically easy and doable. Other manufacturers didfor Drones its not in our han ...

Nils,

You're not understanding the question.

How would you trigger the shutdown in a way that won't hurt the drone if still airborne?

You're comparing a car that's always on the ground, big difference!

nils.heidorn Posted at 2016-12-1 17:44
Please read and may update your knowledge of current active safety features in cars...
Its technica ...

What happens if a drone cuts out in the sky and falls on somebody's head, tell me the drone company who has devised a way to stop this happening.

Mooney Posted at 2016-12-1 17:56
Nils,

You're not understanding the question.

The automatic safety sgutdown would be triggered atomatically, not by the User (not like disarm / CSC).
And as i tried to Detail, it would only happen in situation when flight is out of control.

Nils

hallmark007 Posted at 2016-12-1 17:57
What happens if a drone cuts out in the sky and falls on somebody's head, tell me the drone compan ...

The difference is having a drone falling down with e.g. 1 prop broken, all others still spinning, shredding its crash site to pieces OR a drone falling without spinning props.
No one wants to simply drop a drone out of the sky, its about minimizing damage IF its out of control and crashing anyways.

Nils

nils.heidorn Posted at 2016-12-1 12:57
The difference is having a drone falling down with e.g. 1 prop broken, all others still spinning,  ...

The craft is built extremely well and has safety features, but if they are not to your liking then it is not the craft for you and look for one that does exactly what you want.

DJI-Ken Posted at 2016-12-1 19:05
The craft is built extremely well and has safety features, but if they are not to your liking the ...

Hello Ken,
well i am sure your product managers and developers plan on Improvements.
As there are already videos around of Mavics crashd and still spinning thats a danger and simply not good enough.
Its like all those antique Phantom videos, tech advanced until then.
So instead of feeling threatened just start thinking about the fact that an (optional) "be super safe" is possible and maybe wanted by more customers.
Just dare to ask, i think you'll be surprised.
DJI customers hae to look "out of their box" to see that advancements have been made apart from DJI.

The Mavic is a gem, i dont vare for Inspire / Phantom but the Mavic is unique but theres always room for improvement.

Nils

hallmark007 Posted at 2016-12-1 17:54
I can tell you airbags will not help anyone on the outside of a car crash.

YOu are certainly right :-)
But it was an example for active safety, so humans will be protected by automatic safety features, THAT was the analogy.
And i heard thee also plans for airbags in the front bumper but that might have been marketing blurb (Toyota).

And the Mavic could be safer just with some lines of code, no Hardware Retrofitting needed...

Nils

I think the answer is not to flip the mavic. Start with a hubsan x4 or similar and learn to fly and build confidence.

Warrior200 Posted at 2016-12-1 20:20
I think the answer is not to flip the mavic. Start with a hubsan x4 or similar and learn to fly and  ...

Well, i fly Multicopters since long years, of course starting with toy copters but flying those (or later racers) doesnt help much with the "smart" drones IMHO.

The Mavic stands for nearly autonomus Systems with should-be automatic safety features.
Its something complete different then toy copters or Acro racers. Racers certainly DONT want auto-motor-off at 90 degree angle, would crash a lot :-)
But for "cruising" drones as the Mavic its an emergency situation if it is turned upside down, NOT doable by controlling it manual so it could trigger a auto-stop-motor to prevent more hazard.
(It will come down anyways, no need to have the props shredding stuff).

Nils

In the midst of all this thread's craziness, has anyone answered the basic question:  How do you shutdown a Mavic that has crashed and is still spinning its props?  I'd hate to flip mine up-side-down, but I'd also like to know how to stop the props as soon as possible if I did.

That said, I MUCH RATHER have my Mavic continue to try to fly if it hit something or gets flipped up-side-down while still in the air.  The video above shows a good reason to have that ability and I have seen a torture-test of the Mavic which showed its ability to recover and continue to fly safely after multiple impacts with a tree... and to do so when only about 10 feet off the ground!

Finally, relying on the manufacturer to protect against all types of crashes is both irrational and unrealistic.  In every country I'm aware of, you're required to maintain visual contact with your AC without unaided eyes.  Flying FPV is no excuse for not being able to fly if/when the camera goes down or being able to shutdown if it falls out of the sky.  Now, many will fly FPV (only) anyway, but that becomes the responsibility of the PILOT, not the AC manufacturer.

JMHO.

I think if the mavic crashes the props would break off anyway or the battery would come off . I think learning to fly "toy" multi rotors  and race quads will help when the mavic goes into atti mode.

Nils,

Here's a couple more examples of Mavic's that would have either been damaged or destroyed if the system shutdown after becoming inverted or motors obstructed.  

While I realize many of these simply come down through trees, skip forward to these two clips;

1:37 AMAZING recovery and quite lucky as the drone was headed for the concrete sidewalk and made a last minute recovery despite going inverted and motor binds (both reasons you would have powered it down)

2:15 High altitude collision with kite tail, motor obstruction, inverted multiple times.  Looking at the altitude a complete shutdown would have surely destroyed this Mavic.

Adding a feature to the software to identify and shutdown the systems just isn't the simple solution you request.

Mooney Posted at 2016-12-1 14:45
Nils,

Here's a couple more examples of Mavic's that would have either been damaged or destroyed if  ...

Ok, I know there are helicopters out there that have "cable cutters" on the blades... how do I get them on my Mavic props!?!?!?!?!


Ok, some quick research clarified my understanding of the cutter system.  It's not on the blades, it is made for forward flight.  Maybe I'll just sharpen the leading edges of all my blades... or better yet, just try to stay away from kites.  LOL!

nils.heidorn Posted at 2016-12-2 03:26
Well, i fly Multicopters since long years, of course starting with toy copters but flying those (or ...

   What are you talking about .... The mavic has many saftey features..... Yes it doesnt have an auto crash detection shut down. The mavic also doesnt have an inbuilt toaster, bread maker or nail clippers....

    Im sure Dji could have included all these features but nobody is going to pay 10k for that drone.... Much smarter people than you are designing these products, if the mavic doesnt have the features you want buy another product ????  DERP

Gary Mac Posted at 2016-12-1 20:39
In the midst of all this thread's craziness, has anyone answered the basic question:  How do you shu ...

Hi !
I agree, one should have the choice of activating that "advanced active safety settings or not.
I also saw that recovery video of the Mavic, quite cool...

And also agreed, still no answer from the officials about how to stop that darn thing if push comes to shove.

But about the automatic systems: everything is going that way, the Mavic is halfway there so adding a few tidbits would advance it even more IMHO.
If you are for raw fun you can have that TBS Discovery :-)

Nils

OP Here,

The original question was how I can manually shut it down. A few mentioned in the user manual where it says,

"Stop Motors Mid-flight

Stop motors mid-flight will cause the aircraft to crash. The motors can only be stopped mid-flight when the flight controller detects a critical error. (This setting can be changed in the DJI GO app)"

The thing is, I searched through all of the settings and couldn't find anything about this.

Also, my bad crash in question, I hit a tiny branch while about 3 feet above the ground over soft grass. Shouldn't have been an issue. Instead, it hit the ground, spun to its side, slashed its way to the street and spun around upside down for a while until the blades were destroyed. The gimbal may have been damaged too. What should have been a minor crash leading to no problems turned into a much bigger problem. Had there been people around or a car, it could have been a much bigger issue!

Picture is of what's left of the blades.

fl4InR8qpSw8 Posted at 2016-12-1 21:19
OP Here,

The original question was how I can manually shut it down. A few mentioned in the user man ...

Sorry to hear about your crash,
Yes there need to be a safe way to turn of the motors in such situations.
Good luck

fl4InR8qpSw8 Posted at 2016-12-1 21:19
OP Here,

The original question was how I can manually shut it down. A few mentioned in the user man ...

Yes, you re right that a manual CSC / disarm would have been good, but a (smart) automatic way of doing it would have been even faster and wouldve saved more material.
And the sensors TOLD the Flight Computer that the Mavic was grouded and mtors blocked that is NOT a "normal" flight situation so shut that motors down i say
Nils

There should be a throttle cut button. Every RC heli (transmitter) I've ever had has a dedicated button to immediately cut the throttle in the event of a crash or impending doom. If my micro helis didn't have that there would a be a lot more broken parts in my garbage can. When I first saw the mavic controller I though the 5 way button was a throttle cut.

I'd also like to add that during both crashes, one or more of the arms folded themselves in. I would think that should be a pretty good indicator that it shouldn't be trying anymore and should cut the power...

fl4InR8qpSw8 Posted at 2016-12-1 23:22
I'd also like to add that during both crashes, one or more of the arms folded themselves in. I would ...

Ouch YES that only adds to the demand of a proper shutdown in case of emergency.

Haven't thought of that...

Nils

fl4InR8qpSw8 Posted at 2016-12-1 13:19
OP Here,

The original question was how I can manually shut it down. A few mentioned in the user man ...

I had a very similar issue. I was testing Follow Me with an angle and my Mavic hit tree branches from the side and got stuck in the tree. I couldn't turn off the motors so lifted up and w/ the (presumably) damaged propellers the Mavic then hit my house and fell upside down into the rocks w/ the propellers grinding away.  If 1) I could have manually turned off the propellers when the Mavic was stuck in the tree that could have reduced damage and 2) the Mavic would have known it was at 0 feet altitude and upside down shut off it's propellers that could have saved further damage.