Hey Guys,

My family and I had a good time recording this video during our quarantine time.  

I had someone recently ask about the "Emergency Propeller Stop" feature of the Mavic Mini.  This video is to test out and demonstrate that feature in a "safe" manner so as to try not to destroy my Mini or my kids.  Check it out and let me know what you think.

p.s. I recommend keeping this setting at "Emergency Only" unless you really know what you are doing.  I've heard of many people accidentally crashing their drones when they inadvertantly do a CSC in mid-flight.


Thanks,
David

I've heard of many people accidentally crashing their drones when they inadvertantly do a CSC in mid-flight.
CSC is not something that accidentally happens in flight
Anyone that accidentally CSCs in flight was going to crash it anyway.

I always wanted to know how "Emergency Propeller Stop" works. Thanks for your test! As always your videos are very informative and helpful.

Thanks, I already wanted to try it by myself but was too scared. ;) What happens if you get into the emergency-stick-position slowly? I mean, just to know, what could happen if I get to it accidentally while flying and doing shots? Would be interesting to know if the emergency stop is only triggered, when you push the sticks instantly to the positions.

Mizzu Posted at 4-13 01:47
Thanks, I already wanted to try it by myself but was too scared. ;) What happens if you get into the emergency-stick-position slowly? I mean, just to know, what could happen if I get to it accidentally while flying and doing shots? Would be interesting to know if the emergency stop is only triggered, when you push the sticks instantly to the positions.

Indeed...good question.

Mizzu Posted at 4-13 01:47
Thanks, I already wanted to try it by myself but was too scared. ;) What happens if you get into the emergency-stick-position slowly? I mean, just to know, what could happen if I get to it accidentally while flying and doing shots? Would be interesting to know if the emergency stop is only triggered, when you push the sticks instantly to the positions.

I mean, just to know, what could happen if I get to it accidentally while flying and doing shots?
You would be flying backwards-sideways at full speed, while also descending fast and spiralling downwards.
Now .. what was that about accidentally getting into that situation while flying and photographing?
You would have to be flying like a maniac.
No-one is going to accidentally CSC, it just doesn't happen.

Thanks for the demo man. Very informative. I tried to do this on a tello but it was not part of the program...

Mizzu Posted at 4-13 01:47
Thanks, I already wanted to try it by myself but was too scared. ;) What happens if you get into the emergency-stick-position slowly? I mean, just to know, what could happen if I get to it accidentally while flying and doing shots? Would be interesting to know if the emergency stop is only triggered, when you push the sticks instantly to the positions.

I would like to imagine what cinematographical value is in full speed down spiral in either CW or CCW direction.

Did not know that option existing. Had my drone go wonky on takeoff once and end up under a picknick table. Wish I had known about this THEN.

Thanks for sharing.

Cheers!
=C=

Nice demo.  Thanks so much for sharing.

next: try an engine shut-off and then restart before reaching the ground

Mizzu Posted at 4-13 01:47
Thanks, I already wanted to try it by myself but was too scared. ;) What happens if you get into the emergency-stick-position slowly? I mean, just to know, what could happen if I get to it accidentally while flying and doing shots? Would be interesting to know if the emergency stop is only triggered, when you push the sticks instantly to the positions.

That is a good question and one I don't think I'll plan on testing!  

My assumption (which very well could be wrong) is that the sticks just need to be in the final position for a certain amount of time and then the CSC is triggered.  I don't think that the path or time it took to get to that position would matter, but just the amount of time in that actual position.  But again, that is just an an assumption on my part and could very well be wrong.  

I like having a non-broken drone and kids, so I don't think I'll be testing that scenario.  Seems like it would be too difficult to predict where it would be in order to be able to catch it softly like we did in the video.

Guorium Posted at 4-13 02:45
Thanks for the demo man. Very informative. I tried to do this on a tello but it was not part of the program...

I had tried it on a DJI Spark as well a long time ago and it didn't work there either.  I made a video about it too.

Cal Evans Posted at 4-13 04:43
Did not know that option existing. Had my drone go wonky on takeoff once and end up under a picknick table. Wish I had known about this THEN.

Thanks for sharing.

Happy to be able to share.  We had fun being a bit silly while filming it.

Ice_2k Posted at 4-13 06:57
next: try an engine shut-off and then restart before reaching the ground

Haha, I'll leave that one for you to test.  I quite like having a working drone and unscathed kids.  I remember someone made a video with the original Mavic Pro doing exactly that.  I don't have enough disposable income at the moment to risk it.  Maybe if the stock market rebounds dramatically!  

KlooGee Posted at 4-13 07:06
Haha, I'll leave that one for you to test.  I quite like having a working drone and unscathed kids.  I remember someone made a video with the original Mavic Pro doing exactly that.  I don't have enough disposable income at the moment to risk it.  Maybe if the stock market rebounds dramatically!

i feel you, I'm crying over the NY stock market myself )

It’s very strange and I’m not convinced it’s what is meant or what happens, if you look at craft like phantom and inspire there is no spiraling, CSC is left stick down and RTH, so motors stop craft drops, if you read CSC it says only in emergency I had heard many times in the past that CSC could only be engaged if there was a collision or missing motor prop etc, I’m not saying this is correct but I really can’t see the point in the spiraling if there is plenty of options to just shut down motors ie RTH and left stick down, CSC on the ground in normal circumstances is just the IMU realizing craft cannot go any further so shuts motors down, when starting CSC IMU sends message to fire up motors .

Maybe it’s one that needs clearing up, 1, will it cut motors without collision, 2, why the need to spiral .

hallmark007 Posted at 4-13 07:37
It’s very strange and I’m not convinced it’s what is meant or what happens, if you look at craft like phantom and inspire there is no spiraling, CSC is left stick down and RTH, so motors stop craft drops, if you read CSC it says only in emergency I had heard many times in the past that CSC could only be engaged if there was a collision or missing motor prop etc, I’m not saying this is correct but I really can’t see the point in the spiraling if there is plenty of options to just shut down motors ie RTH and left stick down, CSC on the ground in normal circumstances is just the IMU realizing craft cannot go any further so shuts motors down, when starting CSC IMU sends message to fire up motors .

Maybe it’s one that needs clearing up, 1, will it cut motors without collision, 2, why the need to spiral .

I'm a bit confused by your response.

1. When set to "anytime", a CSC will cut the motors without a collision as demonstrated in the video.
2. When set to "Emergency Only", a CSC will only cut the motors when the conditions outlined in the manual (and screenshot into the video) are met.
3. A CSC command doesn't happen immediately.  Even if the drone is on the ground, if you just briefly bring the sticks to the CSC position and release them, the motors won't start/stop.  You have to hold the sticks in the CSC position for a period of time before the CSC command is actually invoked.
4. The spiral is just a byproduct of the fact that the CSC does not invoke immediately.  So the spiral is just doing the movement of the drone as commanded by the sticks until the CSC is invoked.  When the CSC is invoked, then the motors stop immediately (assuming "anytime") is selected.
5.  DJI should update the manual to specify the time period the sticks need to be held in the CSC position for the CSC command is actually invoked.
6.  Having this option set to "anytime" works just like I've read older DJI drones (such as the Phantom 3) work with a CSC command. See the caution note on page 46 of the P3P manual.  https://dl.djicdn.com/downloads/ ... _Manual_v1.8_en.pdf
7.  I've read stories in this forum and others that DJI changed the emergency motor stop to a different sequence on the P4 due to inadvertent invocation on older drones causing crashes.  Its too bad they didn't make this sequence similar for the Mini.  However, due to the placement of the RTH button on the Mini's controller, that may explain the difference.

Cheers.

Ice_2k Posted at 4-13 07:31
i feel you, I'm crying over the NY stock market myself )

Yes, me too!  

KlooGee Posted at 4-13 08:21
I'm a bit confused by your response.

1. When set to "anytime", a CSC will cut the motors without a collision as demonstrated in the video.

p3p old phantom and before it was when stopping motors changed from both sticks straight down and it was this movement over 5 years ago that saw some drones being lost, not sticks to the corner, however there was another change with P4 and subsequent phantoms and inspire, where cutting motors was left stick down and Rth although I think normal CSC also works, so really my problem with this is Left stick down and RTH for 3 seconds does not cause craft to spiral, so would have thought better option, I also have not heard of any doing this unintentionally.

CSC for Emergency Only, beyond vertical speed I guess they take into account roll and pitch angles. Nice and funny test

Thanks for the demo!

Now do this higher and try to restart motors

Thanks for the demo....

Labroides Posted at 4-12 17:50
I've heard of many people accidentally crashing their drones when they inadvertantly do a CSC in mid-flight.
CSC is not something that accidentally happens in flight
Anyone that accidentally CSCs in flight was going to crash it anyway.

I crashed it anyway.
I dint know that so idit the combination accidently. And crashed it from 165meters...
Bad idea.

If you are saying you managed to do a mid air CSC, what mode was the "emergency propellor stop" thing set to?

Did you try restarting the motors as it fell?
How do you normally start the motors?

If the drone will power up and connect etc. the setting of  "emergency propellor stop" may still be set to what it was during the flight of the crash.

If the drone will not power up the information is probably in the flight logs on your phone. If you post, here, both the DAT log and the txt log for the flight someone may be able to dig the information out of those logs

If the  "emergency propellor stop" was set to ''anytime'' holding the CSC position for around 2 seconds will stop the motors. This is TOO QUICK in my opinion.


I sports flight mode with the "emergency propellor stop" thing set to ''emergency only'' I have, starting at 75ft, held the CSC position and continued to hold it whilst the drone descended to an indicated -2ft (i.e.for a drop of 77ft lasting between 12 and 13 second) and the motors did not stop and as soon as I released the sticks the drone stopped its fall and hovered.

Sean-newbie Posted at 7-31 05:55
If you are saying you managed to do a mid air CSC, what mode was the "emergency propellor stop" thing set to?

Did you try restarting the motors as it fell?

If the  "emergency propellor stop" was set to ''anytime'' holding the CSC position for around 2 seconds will stop the motors. This is TOO QUICK in my opinion.
For a long time CSC would instantly cut your motors, which is exactly what you want in an emergency stop mechanism.
And even though new flyers complained about it, people still didn't accidentally CSC in normal flight.
What kind of flying would you have to be doing?
(see my post #7 above).

Labroides Posted at 7-31 06:45
If the  "emergency propellor stop" was set to ''anytime'' holding the CSC position for around 2 seconds will stop the motors. This is TOO QUICK in my opinion.
For a long time CSC would instantly cut your motors, which is exactly what you want in an emergency stop mechanism.
And even though new flyers complained about it, people still didn't accidentally CSC in normal flight.

I can't imagine any stunt flying scenario where one would accidentally invoke CSC in flight.  Anyone familiar enough with how the thing works to even try stunt flying would certainly also be well familiar with the results of using this unique stick position.

I did a video 4 years ago with my Phantom 3 Pro demonstrating how it works, compared to the then newly introduced combination input using the RTH button.

Ladroides, do you have any assistance to give to the person I was answering i.e. djiuser_h1dp5ozy3Fxx of post 35?

What kind of flying would you have to be doing?  Actually the mini executes a quite tidy descending helix even in sports mode and in C mode it is positively dainty and slow

Sean-newbie Posted at 7-31 10:50
Ladroides, do you have any assistance to give to the person I was answering i.e. djiuser_h1dp5ozy3Fxx of post 35?

What kind of flying would you have to be doing?  Actually the mini executes a quite tidy descending helix even in sports mode and in C mode it is positively dainty and slow

So sticks in CSC will give you a helix, I presume you mean a downward helix as opposed to upwards helix. Maybe post the footage, or did you just make that up.

hallmark007 Posted at 7-31 11:18
So sticks in CSC will give you a helix, I presume you mean a downward helix as opposed to upwards helix. Maybe post the footage, or did you just make that up.

Strange, I thought "descending helix" quite clearly means going downwards, am I wrong?

Besides which have you ever heard of, or seen, a drone that climbs when the throttle is closed?
Maybe you live in an Electric Brae.
Yes actually there is video but no I am not going to post it, I do not post video full stop.
But if you doubt my word why on earth would you believe a video? So, to do so for your benefit would be a waste of time

I take it you too are not interested in helping djiuser_h1dp5ozy3Fxx.

Sean-newbie Posted at 7-31 11:39
Strange, I thought "descending helix" quite clearly means going downwards, am I wrong?

Besides which have you ever heard of, or seen, a drone that climbs when the throttle is closed?

I know how to preform a helix and it’s not as you describe, so with no footage I guess I was right just something you made up .

Sean-newbie Posted at 7-31 10:50
Ladroides, do you have any assistance to give to the person I was answering i.e. djiuser_h1dp5ozy3Fxx of post 35?

What kind of flying would you have to be doing?  Actually the mini executes a quite tidy descending helix even in sports mode and in C mode it is positively dainty and slow

Ladroides, do you have any assistance to give to the person I was answering i.e. djiuser_h1dp5ozy3Fxx of post 35?
Before the incident, tell him not to jerk the sticks around like a maniac.
It's a bit late now for assistance or advice.

On a different note, why do the post numbers on this forum slip around all over the place.
His post is no longer #35.
What I had referred to as my post #8 is now #7.
Why don't post numbers stay the same here?

hallmark007 Posted at 7-31 14:02
I know how to preform a helix and it’s not as you describe, so with no footage I guess I was right just something you made up .

Of course, you could always try it for yourself and post the video?

Sean-newbie Posted at 8-1 02:54
Of course, you could always try it for yourself and post the video?

Difference between you and I is I know what happens, you like to make it up..

dream on, my friend, dream on

Hallmark just for you

Didn't answer a thing for me. What is the difference between anytimne and emergency only?

Didn't answer a thing for me really. What is the difference between "anytime" and "emergency only"? Are the operators actions different when it is "anytime" instead of "emergency"?

How does the action or reaction of the drone differ in "emergency only" as opposed to "anytime". Who or what determines whether it is an emergency? If it is the operator then really isn't "emergency" "anytime" anyway as far as the drone is concerned?

Is there a time lag in case it was by mistake. to allow cancellation of the motors off command?

[PS I presume the operation is the same but I own a DJI Mini 2 so I am referring to that with my questions]

Anytime      = the motor will stop when the CSC position is held for around 1.7 seconds
Breakdown = in normal flight the motors will NOT stop, irrespective of how long the CSC position is held.