Failsafe behavior
2870 9 2017-7-13
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Xavier1984
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Hi,
I'm interested to have some feedback about the behavior of a failsafe case :

What does the drone if it is in this case:

- RC signal 0 (lost the RC signal)
- Video signal 0 (lost video feedback)
- Drone flying at about 10-15 meters of height and about 200 meters of the home point (RC point)
- Only 4 GPS signals (so oscillation between 0 - 4 GPS signals)
- RTH altitude set to 60 meters
- Battery is good
- Home Point recorded sucessfully
- Failsafe set to RTH

The drone should be hover, land, RTH ?

Thanks for your help :-)
2017-7-13
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Labroides
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What kind of place are you going to find ....
Drone flying at about 10-15 meters of height and about 200 meters of the home point (RC point)
Only 4 GPS signals (so oscillation between 0 - 4 GPS signals)?

Unless you are flying under cover, in a canyon etc, you are going to have more than 0-4 GPS sats visible.
2017-7-13
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Xavier1984
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I was flying on the side of a hill, following a motorbike on a road in sport mode at about 30-40 kmh. Suddently i lost GPS, RC, VIDEO signal.

That's why i would like to understand ;-) Or the log analyzer is not correct (DatCon)For me it's not an issue to lose RC signal or GPS, it's possible at any time but i try to understand.

AirData : http://app.airdata.com/main?share=QqKtcG

Log : https://www.dropbox.com/s/tjhc0mr27cohwii/FLY188.DAT?dl=0



2017-7-13
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Labroides
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Xavier1984 Posted at 2017-7-13 05:18
I was flying on the side of a hill, following a motorbike on a road in sport mode at about 30-40 kmh. Suddently i lost GPS, RC, VIDEO signal.

That's why i would like to understand ;-) Or the log analyzer is not correct (DatCon)For me it's not an issue to lose RC signal or GPS, it's possible at any time but i try to understand.

If your Phantom has less than 6 GPS sats, it cannot find its way back anywhere.
All it can do is hover and wait for either a control signal or battery to run down to critical low level which would trigger autolanding.

AIrdata isn't going to give you flight data.
To see what was happening go to http://www.phantomhelp.com/LogViewer/Upload/
Follow the instructions to upload your flight record.
Come back and post a link to the report it provides
2017-7-13
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Xavier1984
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Hi
Below the result of the LogViewer (log acquired from the DJI Go 4 application IOS) : http://www.phantomhelp.com/LogViewer/E82YB1BJ9JWN9RVAVGJ2/#

I'm not sure that's the best log to analyze because it's the log of the application and not of the drone itself. When i analyze the log of the drone (.DAT) file and i analyze it with DJI log viewer od DatCon i get many more information. (.DAT file available for download in precedent message).

Capture.JPG

Thanks for the help :-)
2017-7-13
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Genghis9
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Can anyone please fully explain this quote from the manual?
Page 15 of v1.2 Phantom 4 Pro Manual; Ref Failsafe RTH Process

"-Aircraft automatically descends and lands if RTH is triggered when the aircraft flies within a 65 feet (20 meters) radius of the Home Point.  Aircraft will stop ascending and immediately return to the Home Point if you move the left stick if the aircraft reaches 65 feet (20 meters) altitudes or beyond during Failsafe."

I'm primarily hung up on the second sentence "Aircraft will stop ascending and immediately return to the Home Point if you move the left stick if the aircraft reaches 65 feet (20 meters) altitudes or beyond during Failsafe."  I'm failing to understand the left stick movement factor in the process as to what it really means and why.  First, I think this manual is very poorly written, likely due to issues of translation, either way it makes for a poor read trying to understand it at times this is one of them.
I realize it may not be complicated, I just can't figure out what it is they are trying to say.  If anyone can help clear this up and explain it in detail, I would appreciate it, please.
Thank you

2017-8-24
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Labroides
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Genghis9 Posted at 2017-8-24 05:23
Can anyone please fully explain this quote from the manual?Page 15 of v1.2 Phantom 4 Pro Manual; Ref Failsafe RTH Process
"-Aircraft automatically descends and lands if RTH is triggered when the aircraft flies within a 65 feet (20 meters) radius of the Home Point.  Aircraft will stop ascending and immediately return to the Home Point if you move the left stick if the aircraft reaches 65 feet (20 meters) altitudes or beyond during Failsafe."
I'm primarily hung up on the second sentence "Aircraft will stop ascending and immediately return to the Home Point if you move the left stick if the aircraft reaches 65 feet (20 meters) altitudes or beyond during Failsafe."  I'm failing to understand the left stick movement factor in the process as to what it really means and why.  First, I think this manual is very poorly written, likely due to issues of translation, either way it makes for a poor read trying to understand it at times this is one of them.I realize it may not be complicated, I just can't figure out what it is they are trying to say.  If anyone can help clear this up and explain it in detail, I would appreciate it, please.

1st sentence:  
If you initiate RTH when the Phantom is less than 20 metres from home, it will just land where it is rather than return.

2nd sentence:
If your Phantom is already above 20 metres up and you use the left stick while the Phantom is ascending to RTH height, you will cancel the ascent and the Phantom will come home at the altitude it is at.
2017-8-24
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Genghis9
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Labroides Posted at 2017-8-24 15:25
1st sentence:  
If you initiate RTH when the Phantom is less than 20 metres from home, it will just land where it is rather than return.

Labroides,
Thanks, I'm clearly a dense person, I still had to read it twice to let it sink in.  However, what you stated makes a whole lot more sense then what was written.  I am absolutely certain that I would never have guessed those answers based on what and how it was written.
So, what am I missing here with reading this manual?  What I mean is, did you figure this out just reading it (good on ya if you did) or have you tested this stuff and based it on your actual experience.  I'm really struggling to understand a lot of areas in the maual, because of the grammer and logic flow errors.  If there is a trick to it, or a better written document that I can use please let me in on it.
Thanks again!

2017-8-24
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Labroides
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Genghis9 Posted at 2017-8-24 17:27
Labroides,
Thanks, I'm clearly a dense person, I still had to read it twice to let it sink in.  However, what you stated makes a whole lot more sense then what was written.  I am absolutely certain that I would never have guessed those answers based on what and how it was written.
So, what am I missing here with reading this manual?  What I mean is, did you figure this out just reading it (good on ya if you did) or have you tested this stuff and based it on your actual experience.  I'm really struggling to understand a lot of areas in the maual, because of the grammer and logic flow errors.  If there is a trick to it, or a better written document that I can use please let me in on it.

You are correct about the poor writing and/or translation.
Lots of testing helps to work things out..
2017-8-24
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Xavier1984
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Labroides Posted at 2017-8-24 18:43
You are correct about the poor writing and/or translation.
Lots of testing helps to work things out..

I personally prefer a correct and good manual that testing the recovery of my drone...

;)
2017-8-24
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