Descending with Phantom 4

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3 years ago I received the original Phantom 1, with that version I had to be careful to don't decrease the throttle too much otherwise it would fall out of the sky.

Does anybody knows. Would the motor stop in flight if I would decrease the throttle all the way down?
 
Interesting question.

I was just setting mine up in doors and have yet to fly. However, to initiate the motors you bring the sticks to the corner. To shut them off, you just hold down on the left stick for 1-2 seconds. I'm guessing Arthur is asking what I'm thinking as well, which is it you hold it down to descend, will it shut the motors off? Or does it know it's in the air and will not do that?

**I should have read Sar's post better. I see that he mentioned once the aircraft it detects it's no longer descending.
 
I'm not sure if we're discussing the same thing but. The left joystick controls the ascend/descend instead of throttle which in turn affects the throttle to go up or go down. Unlike manual quadcopters where the left joystick controls the throttle which in turn makes them go up and go down.

Left joystick is also leveled in the middle and it returns to middle when released. You can crank it all the way down and the Phantom will descend, once you let go, joystick will return to neutral position and it'll stop at that altitude.
 
I'm not sure if we're discussing the same thing but. The left joystick controls the ascend/descend instead of throttle which in turn affects the throttle to go up or go down. Unlike manual quadcopters where the left joystick controls the throttle which in turn makes them go up and go down.

Left joystick is also leveled in the middle and it returns to middle when released. You can crank it all the way down and the Phantom will descend, once you let go, joystick will return to neutral position and it'll stop at that altitude.


P4 in "mode2", that is correct.
 
Left stick down for 3 seconds has generally been regarded as the best way to shut down the motors - it produces no motor speed asymmetries and is less likely to cause the aircraft to topple over than a CSC, which does put the sticks into an asymmetric configuration.
 
Happy to report the descending function works like a charm. Today I tested several times. In flight pushed the throttle all the way down, the Phantom came down like a spider on a thread. Beautiful, stable. Yet when landed in my hand and there was no more vertical movement it shut down.
Of course sar104 would say, I told you so. :)
 
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Isn't it the VPS that tells the flight board where you are in relation to solid ground and will shut off at full descend speed when it determines it is on solid ground for 3 seconds. And you don't have to worry about darkness or brightness because DJI, in their infinite wisdom have used redundancy by using ocular and sonar for detecting the ground now from up to like 14 feet or something,

Sonar works like this which is why darkness doesn't matter. It is however confused by solid looking matter like water and deep commulas clouds. Myth or not, I've heard stories of Ps that thought they were on the ground in a cloud.
2000px-Sonar_Principle_EN.svg.png
 
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Isn't it the VPS that tells the flight board where you are in relation to solid ground and will shut off at full descend speed when it determines it is on solid ground for 3 seconds. And you don't have to worry about darkness or brightness because DJI, in their infinite wisdom have used redundancy by using ocular and sonar for detecting the ground now from up to like 14 feet or something,

Sonar works like this which is why darkness doesn't matter. It is however confused by solid looking matter like water and deep commulas clouds. Myth or not, I've heard stories of Ps that thought they were on the ground in a cloud.
2000px-Sonar_Principle_EN.svg.png

Previous versions have just used the barometric reading to detect no further descent. It is quite conceivable that the P4 could also use VPS and GPS/GLONASS for vertical movement data, but I don't think I've seen that mentioned in the documentation.
 
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Previous versions have just used the barometric reading to detect no further descent. It is quite conceivable that the P4 could also use VPS and GPS/GLONASS for vertical movement data, but I don't think I've seen that mentioned in the documentation.
I can't remember if I heard that or made it up because that's what I thought the VPS was. Thanks for telling me. I will defer to your more educated theory. What then is the point of VPS?
 
I can't remember if I heard that or made it up because that's what I thought the VPS was. Thanks for telling me. I will defer to your more educated theory. What then is the point of VPS?

Additional 3-D stability, especially when GPS is poor, or indoors.
 
Left stick down for 3 seconds has generally been regarded as the best way to shut down the motors - it produces no motor speed asymmetries and is less likely to cause the aircraft to topple over than a CSC, which does put the sticks into an asymmetric configuration.

Also good for hand catching. :cool:
 
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