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Has Anyone Ever Tested the Emergency Propeller Stop Function Recently?

LoudThunder

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What am I missing? In the DJI Mini 2 User Manual, Version 1.4, dated June 2021, on page 35, Paragraph 6. Systems Settings:

Advanced Settings: includes Emergency Propeller Stop and Payload mode. "Emergency Only" indicates that the motors can only be stopped mid-flight in an emergency situation such as if there is a collision, a motor has stalled, the aircraft is rolling in the air, or the aircraft is out of control and is ascending or descending very quickly. "Anytime" indicates that the motors can be stopped mid-flight anytime once the user performs a combination stick command (CSC). Stopping the motors mid-flight will cause the aircraft to crash

I know this sounds weird, but I believe in "Proof-of-Concept" and "Risk Assessment." I had to; I did this daily for over 30-years in the Air Force. I was a Computer Programmer and I programmed major computer systems and I had to prove the coding did what it was required to do. I had to anticipate all the events that could mess things up, like incorrect user input (Accept Y or N for Yes or No, but reject all other options), and if a hard drive should fail, to have a working back-up to quickly restore the system. If we had an emergency "Kill Switch" to test it to ensure the whole system is brought down safely and correctly…

So, having read about this option in the Advance Settings, I wanted to test it out. My Mini 2 is being flown in Mode 2 (Throttle and Yaw on the Left) and (Roll and Pitch on the Right) and it has the latest firmware updates.

So, having selected the "Anytime" option, I flew my drone over tall grass (expecting it to drop like the proverbial stone…) and when I tested it in Option "A", the drone merely descended quick yawing to the Right while backing up to the Left, without stopping the motors… And when I tried Option "B", the drone descended quick yawing to the Left while backing up to the Right, again without stopping the motors…

I also tried setting the "Emergency Propeller Stop" to Emergency Only with the same results.

Now, when the Drone is sitting on the Landing Pad (ready to fly), either of these stick positions will start the motors or stop the motors if it's just "idling" on the pad. This is as specified in the manual.

What I do not know, is this a non-working option that never worked or perhaps stopped working due to a recent software/firmware update? Have any of you ever tested or had to use this feature.

I have several grandkids, nieces, nephews, and neighbor kids that come running into the yard to see the drone. And I would rather crash the drone than risk running the drone into the face of a child.

Call me an old softy… But "Enquiring Minds Want to Know…"

emergency.png
 
In anytime there is a short delay, less than 2 seconds. If it worked instantly there is too great a chance of accidentally stopping the motors in mid air.


 
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What am I missing? In the DJI Mini 2 User Manual, Version 1.4, dated June 2021, on page 35, Paragraph 6. Systems Settings:

Advanced Settings: includes Emergency Propeller Stop and Payload mode. "Emergency Only" indicates that the motors can only be stopped mid-flight in an emergency situation such as if there is a collision, a motor has stalled, the aircraft is rolling in the air, or the aircraft is out of control and is ascending or descending very quickly. "Anytime" indicates that the motors can be stopped mid-flight anytime once the user performs a combination stick command (CSC). Stopping the motors mid-flight will cause the aircraft to crash

I know this sounds weird, but I believe in "Proof-of-Concept" and "Risk Assessment." I had to; I did this daily for over 30-years in the Air Force. I was a Computer Programmer and I programmed major computer systems and I had to prove the coding did what it was required to do. I had to anticipate all the events that could mess things up, like incorrect user input (Accept Y or N for Yes or No, but reject all other options), and if a hard drive should fail, to have a working back-up to quickly restore the system. If we had an emergency "Kill Switch" to test it to ensure the whole system is brought down safely and correctly…

So, having read about this option in the Advance Settings, I wanted to test it out. My Mini 2 is being flown in Mode 2 (Throttle and Yaw on the Left) and (Roll and Pitch on the Right) and it has the latest firmware updates.

So, having selected the "Anytime" option, I flew my drone over tall grass (expecting it to drop like the proverbial stone…) and when I tested it in Option "A", the drone merely descended quick yawing to the Right while backing up to the Left, without stopping the motors… And when I tried Option "B", the drone descended quick yawing to the Left while backing up to the Right, again without stopping the motors…

I also tried setting the "Emergency Propeller Stop" to Emergency Only with the same results.

Now, when the Drone is sitting on the Landing Pad (ready to fly), either of these stick positions will start the motors or stop the motors if it's just "idling" on the pad. This is as specified in the manual.

What I do not know, is this a non-working option that never worked or perhaps stopped working due to a recent software/firmware update? Have any of you ever tested or had to use this feature.

I have several grandkids, nieces, nephews, and neighbor kids that come running into the yard to see the drone. And I would rather crash the drone than risk running the drone into the face of a child.

Call me an old softy… But "Enquiring Minds Want to Know…"

View attachment 144508
Ok my mini SE settings same,,got me curious on that now I read your post,,mayby it's not functional until the rpms are higher instead of at idle speed,,I cant test ,its night time but I would try letting it hover mayby 1 mtr above a pillow then try shut it down,,,I'll try myself tomorrow, 20220226_204139.jpg
 
Make it interesting , go up to 100 meters and do it , and see if you can restart before hitting the deck

I've seen it done with a Mavic Pro about four years ago.




Years ago, the DJI Spark came out and the CSC maneuver didn't work, although it was in the manual.

I've tried with the Spark and it didn't work.

I'm not going to try it with the MA2.

If someone has Care Refresh and willing to use it, give it a try. :D

.
 
What am I missing?
We have recently in the forum had a couple incidents with crafts falling dead from the air ... in all cases the CSC command setting was set to "Always" & the pilots did some unusual movements making them putting the sticks into the CSC command position.

Here a case with a Mavic 3 from November last year with the craft flying above 200ft & dropping dead to the ground ...

In below chart you have all 4 stick positions ... the chart marker is placed just when the pilot position the sticks in the CSC command at 751,7sec into the flight (stick value 1024 = stick neutral) ... have pasted in a pic to show the stick position in an easier way. Note that the motors is reported to be ON.

(Click on the chart to make it larger)
1645877106058.png

In below chart at 753,3sec into the flight the sticks are still in the CSC command position ... the log ends & the motors is reported to be OFF (the log only records when the motors is on).

The timing in between when a "FULL" CSC command was given & the motors shut off was 1,6sec ... the actual delay programmed into the FW might be slightly longer as it may be sufficient to place the sticks past a certain threshold value for it to consider it to be placed in the CSC command position ... maybe a total full command isn't necessary, we for instance see a similar threshold for a down throttle command when the craft is 0,5m above ground according to the VPS sensor ... a full throttle command isn't necessary to make it enter auto landing ... but the throttle needs to be at least over approx. 80% of full down.

So trying this from a low & crash safe height may be difficult depending on the crafts descent speed ... in this case with the Mavic 3 it descended 24ft during the CSC delay.

(Click on the chart to make it larger)
1645878009980.png

And here you have a video from a Mini 2 where it happens also ...

 
Make it interesting , go up to 100 meters and do it , and see if you can restart before hitting the deck
I wouldn't recommend such a test but if you do BE SURE TO RELEASE THE STICKs BETWEEN MOTOR STOP and the attempted re-start.
The original poster of the second thread of post #2 did not, see post #34 in that thread. Its not certain if that was the reason for no motor re-start but it will not have helped.
 
I have several grandkids, nieces, nephews, and neighbor kids that come running into the yard to see the drone. And I would rather crash the drone than risk running the drone into the face of a child.
Always keep a safe altitude. Number one rule in aviation
 
Make it interesting , go up to 100 meters and do it , and see if you can restart before hitting the deck
Thank you for your suggestion, but I enjoyed your posting so much that I would not want to steal you thunder; I'll let you to be the first to attempt this test.

As for me, if the quick shut-down worked, there is no guarantee that the Drone would be in the proper orientation (while it tumbled to the ground) to successfully get a motor restart…

But, before you test your hypothesis, check to make sure your Care Refresh Policy is current…

Once again, thank you for your suggestion, but I'll pass…

Drop.png
 
I want to thank everyone for their input. You've given me a lot to think about. When I am flying low (Child's face height…) I am in my back yard and it's fenced, but not locked. My concern is the child that will "sneak up on Grandpa" while my mind is concentrating on some difficult maneuver.

I want to become extremely adept with the sticks, performing manual: Orbits, Helixes, Dronies, Rockets, Spinning Orbits, Crab Tracking, Semi-Crab Tracking, and all of this in Reverse Command Controls…

I'm practicing (actually attempting) flying in a specific direction to a specific location while yawing (I call it the straight line twirl…). Right now, I'm still flying like a "drunken sailor." I know I can play with the RTH, fly to the specific location, set a new RTH location, activate the RTH and then Yaw the Drone while it returns to home.

The Twirl is perhaps the maneuver which has made me decide to put "Emergency Propeller Stop" into the "Emergency Only" mode. To fly the Clockwise Twirl, I have to slowly move the Right Stick thru the 12 o'clock to 11, to 10, and so forth while slowly moving the left stick to the Right (straight 3 o'clock…) but as you see, I'm putting the sticks in some extreme positions and if would not be surprised to see me accidently hit those Critical Positions long enough to kill the motors.

As I said in my original post, I am always trying to maintain situation awareness. In my "gazzilion" miles of driving, I have had only 2-acidents, one I was hit from behind at a stop light, I saw it coming, but I was in the middle of a 3-lane road with cars on both sides of me…). The other, I took the A/C unit off my RV going under a gas station awning (but in my favor, the entrance was high enough to go under, the rear of the awning was lowered to allow the rain to drain off, and that I did not anticipate…). But over the years, I have avoided numerous accidents, but not pulling up close to the car ahead of me, leaving me room to pull forward to either give the car behind some more stopping room or to quickly scoot onto the shoulder while the car from behind smashed into the car that was ahead of me (which has happened twice…)

So, you see why I wanted the option to STOP the motors quickly if I could not quickly "duck out of the way…"

So, once again, thank all of you for taking the time to respond to my question so it's Emergency Only…
upside down.png
 
Tried this with my mini in a similar environment. The sound when it hit the ground still flashes through my brain every time I fly.
 
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We have recently in the forum had a couple incidents with crafts falling dead from the air ... in all cases the CSC command setting was set to "Always" & the pilots did some unusual movements making them putting the sticks into the CSC command position.

Here a case with a Mavic 3 from November last year with the craft flying above 200ft & dropping dead to the ground ...

In below chart you have all 4 stick positions ... the chart marker is placed just when the pilot position the sticks in the CSC command at 751,7sec into the flight (stick value 1024 = stick neutral) ... have pasted in a pic to show the stick position in an easier way. Note that the motors is reported to be ON.

(Click on the chart to make it larger)
View attachment 144510

In below chart at 753,3sec into the flight the sticks are still in the CSC command position ... the log ends & the motors is reported to be OFF (the log only records when the motors is on).

The timing in between when a "FULL" CSC command was given & the motors shut off was 1,6sec ... the actual delay programmed into the FW might be slightly longer as it may be sufficient to place the sticks past a certain threshold value for it to consider it to be placed in the CSC command position ... maybe a total full command isn't necessary, we for instance see a similar threshold for a down throttle command when the craft is 0,5m above ground according to the VPS sensor ... a full throttle command isn't necessary to make it enter auto landing ... but the throttle needs to be at least over approx. 80% of full down.

So trying this from a low & crash safe height may be difficult depending on the crafts descent speed ... in this case with the Mavic 3 it descended 24ft during the CSC delay.

(Click on the chart to make it larger)
View attachment 144511

And here you have a video from a Mini 2 where it happens also ...

Ouch!
 
It happened to me yesterday with Mini 2.

Flying backward and down (quite common situation) and you are already in a red zone. To move sticks further toward middle is easy and will result in a crashed drone.

It is easy to make this combo happen during the flight, you need to change this option in menu, I didn’t, and I don’t have drone anymore.

As someone mentioned, this really should be bind to like home button + right stick down, or some other, hard to press by accident combo. And not be buried somewhere in the middle of the manual but bolded in red letters on “flying your drone” page.

I simply could not believe you can shut off your drone during the flight just like that.

Yes, emergency shut down must be there, but user needs to able to control it, and I surely was not in control of my actions. Pulling both sticks down in certain position while looking above where your drone goes is easy. This drone could have landed somewhere else, and cause something way more serious. If I want to crash my drone due to certain reasons, I need to able to do that with 100% certainty and knowing what I am doing.

There are certain number of people who crashed their drone cause of this (reported cases), I guess this number is way higher since many just don’t care and they don’t report it. Nothing you can do really, but you can warn others like this, at least to be careful.

Large user base is something every product need, their experience change how things works, but it takes time.

I am quite sure this combo will change over time, you just need enough "accidents" to make it happen.

Happy flying :)
 
It happened to me yesterday with Mini 2.

Flying backward and down (quite common situation) and you are already in a red zone. To move sticks further toward middle is easy and will result in a crashed drone.

It is easy to make this combo happen during the flight, you need to change this option in menu, I didn’t, and I don’t have drone anymore.

As someone mentioned, this really should be bind to like home button + right stick down, or some other, hard to press by accident combo. And not be buried somewhere in the middle of the manual but bolded in red letters on “flying your drone” page.

I simply could not believe you can shut off your drone during the flight just like that.

Yes, emergency shut down must be there, but user needs to able to control it, and I surely was not in control of my actions. Pulling both sticks down in certain position while looking above where your drone goes is easy. This drone could have landed somewhere else, and cause something way more serious. If I want to crash my drone due to certain reasons, I need to able to do that with 100% certainty and knowing what I am doing.

There are certain number of people who crashed their drone cause of this (reported cases), I guess this number is way higher since many just don’t care and they don’t report it. Nothing you can do really, but you can warn others like this, at least to be careful.

Large user base is something every product need, their experience change how things works, but it takes time.

I am quite sure this combo will change over time, you just need enough "accidents" to make it happen.

Happy flying :)
thanks for the very helpful tip, I'll just descend foward from now on ._.

RIP Mini
 
It is easy to make this combo happen during the flight, you need to change this option in menu, I didn’t, and I don’t have drone anymore.
Yes it is easy to make the combination BUT the fact that it actually stopped the motors means that at some point you or someone changed the response setting from the default of "Emergency Only" to "Anytime (Use with caution)".

With the response set to the default, the CSC position WILL NOT stop the motors with the drone in mid air UNLESS the drone itself thinks it has suffered an 'emergency'.
This has been tested and, in a normal flight, the result of the CSC position with the response set to "emergency only" is a descending helix.

You might find
Would it be safe to practice a CSC shutdown a few feet over a mattress?
interesting.
 
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