Props (motors) can stop during flight on P2V

[RichardGHamilton]

Hello Group.
I am new here and have had the Phantom 2 Vision for just a week and flying with it well.
Apologies if this info is somewhere else, yet I did not find it during a search.

I noticed today (during a ground test), that if I pull back and hold ONLY the left controller (transmitter) joystick for about 3 seconds or longer, the props will suddenly stop. Fortunately I have never done this during flight or else the P2V would probably have plummeted from the sky like a brick.

I am baffled as to why the firmware would allow a simple operation like that to turn off the motors completely? I think this should never occur and won't if it is due to some sort of mis-calibration or perhaps a firmware issue. Frankly speaking, I think the motors should NEVER be able to be stopped unless a VERY LONG (5 seconds or more) holding of both joysticks are done at the lower corners.

Anyone else experience this, or am I overlooking something simple? :?:
Thanks,

"Zapper"

 

[xgeek]

That is the best method for turning of the motors. It can not happen in flight as the NAZA detects that the Phantom is descending. It only shuts down the motors once it has detected the Phantom has come to a stop.

 

[RichardGHamilton]

That is the best method for turning of the motors. It can not happen in flight as the NAZA detects that the Phantom is descending. It only shuts down the motors once it has detected the Phantom has come to a stop.

You are one smart cookie. Nowhere could I find that information and I much appreciate your thoughts. It makes a lot of sense. I do wonder however about occasional reports that I see where a person will say their P2V sudden dropped out of the sky. I hope that wasn't due to the NAZA thinking "hey I am on the ground, so lets shut down those props

fyi, this seems like a fabulous board and hope I can contribute when I come up to speed on this stuff. Flying the P2V is almost as much fun as flying an old F4 from a carrier.... hey, I said ALMOST !!!

 

[RickF]

That is the best method for turning of the motors. It can not happen in flight as the NAZA detects that the Phantom is descending. It only shuts down the motors once it has detected the Phantom has come to a stop.

xgeek, this is huge information. I'm sorry to question you but I am always concerned about going to far down with the throttle when I'm bringing the Phantom home. So I must ask two questions: 1) are you sure holding the throttle down during flight will not shut the Phantom down? I know I don't want to give it a try. 2) If you are sure do you know if this feature of the NAZA will also behave the same when using a Futaba 14SG radio, which does not have a self-centering throttle?

Your knowledge regarding this is going to go a long, long way in reducing my anxiety level. Thank you in advance!!

 

[bernardb]

This is from the Naza Manual...don't know if this makes it clearer or muddier:

Stop Motor: We provide two options to stop motors in the assistant software: Immediately and Intelligent.

(1) Immediately Mode: If you select this mode, in any control mode, once motors start and throttle stick is
over 10%, motors will not stop immediately only when throttle stick is back under 10% the motors will
stop. In this case, if you push the throttle stick over 10% within 5 seconds after motors stop, motors
will re-start, CSC is not needed. If you don’t push throttle stick after motors start in three seconds,
motors will stop automatically.

(2) Intelligent Mode: By using this mode, different control mode has different way of stopping motors. In
Manual Mode, only executing CSC can stop motors. In ATTI. Mode or GPS ATTI. Mode, any one of
following four cases will stop motors:

a) You don’t push throttle stick after motors start within three seconds;
b) Executing CSC;
c) Throttle stick under 10%, and after landing for more than 3 seconds.
d) If the angle of multi-rotor is over 70°, and throttle stick under 10%.

 

[bernardb]

This is in addition to the previous....all from page 10 of the manual:

Notes of Intelligent Mode & Immediately Mode

(1) If you choose the Immediately Mode, you should not pull throttle stick under 10% during flight,
because it will stop motors. If you do it accidentally, you should push the throttle stick over 10% in
5s to re-start motors.

(2) DO NOT execute the CSC during normal flight without any reason, or it will stop motors at once.


(1) If you choose the Intelligent mode, and the throttle stick is under 10%, this will trigger the landing
Procedure, in any control mode. In this judgment, pitch, roll and yaw controls are denied except
the throttle, but multi-rotor will still auto level.

(2) In any control mode, DO NOT pull throttle stick under 10% during normal flight without any
reason.

(1) Any of these two cut off types will only work properly if TX calibration is correct done.

(2) In failed-safe, CSC is denied by the main controller, motors will hold their state.

 

[bobomet]

Why exactly would you ever pull and hold the left stick all the way down during flight?

 

[xgeek]

Arh I said pulling the left stick down won't shut off the motors while in flight . Unfortunately the same can't be said for doing a CSC combo while in flight.

Doing any of the following in flight will stop the Phantom dead and it will plummet like a brick to its death.

 

[RichardGHamilton]

Why exactly would you ever pull and hold the left stick all the way down during flight?

Well, to descend at the highest rate from a high altitude. Since it is quoted that the P2V would be limited to descend at a max rate of about 3 meters/sec, then I expect it should be acceptable to pull the stick all the way back.

However, bottom line to me is that in any design, the system should allow for the unexpected to be done by a user.. at least that is the way I've always designed electronics and software. I should think that a system like this should be smart enough to not allow the motors to be turned off in flight under any circumstance of stick movement. It is real easy to do that in software and with sensors.

 

[bostonlines]

Why exactly would you ever pull and hold the left stick all the way down during flight?

I do it all the time when I want to descend quickly. But I only do it in bursts out of fear of the motors stopping in mid flight like the OP mentioned.

 

[bostonlines]

That is the best method for turning of the motors. It can not happen in flight as the NAZA detects that the Phantom is descending. It only shuts down the motors once it has detected the Phantom has come to a stop.

Not sure if this is accurate because I catch it in mid air and stop the motors. I'm pretty sure my hands are never stable when turning it off.

 

[RichardGHamilton]

Arh I said pulling the left stick down won't shut off the motors while in flight . Unfortunately the same can't be said for doing a CSC combo while in flight.

Doing any of the following in flight will stop the Phantom dead and it will plummet like a brick to its death.

NICE POSTING and very visual. I am baffled as to why the engineers would ever consider this to be a safe thing to do for turning off the motors. Considering the terrible consequences, there are better ways to do this. It sort of reminds me of Apple and their not putting in a feature to prevent use of a stolen phone. I guess this ensures continued sales after you crash your P2V. ;-)