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What happens when GPS blocked by trees?

ash2020

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Hi all.
When I'm flying out in the open, with loads of satellites in view and I suddenly go under the tree canopy, blocking most of the sky, will it immediately go into Atti mode? I haven't tried it yet but I wanted to check that it wouldn't suddenly go berserk! Presumably it will still fly visual and stable enough?
Cheers
Andrew
 

Exphantomflyer

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Hi all.
When I'm flying out in the open, with loads of satellites in view and I suddenly go under the tree canopy, blocking most of the sky, will it immediately go into Atti mode? I haven't tried it yet but I wanted to check that it wouldn't suddenly go berserk! Presumably it will still fly visual and stable enough?
Cheers
Andrew
Depends on the tree cover, it would have to be quite dense for the quad to lose all satellites but yes if it does it will enter ATTI mode, low light will also turn off the forward sensors but the downward sensors will still function if you are below 20ft i think it is
 

ash2020

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Depends on the tree cover, it would have to be quite dense for the quad to lose all satellites but yes if it does it will enter ATTI mode, low light will also turn off the forward sensors but the downward sensors will still function if you are below 20ft i think it is
Thanks for that. I will do some real tests soon - if it would only stop raining!
 
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Trees do not really block the GPS signal that much. As stated above, if its very very dense you may have an issue. I would be more concerned about WiFi being blocked (and hence connection issues) than GPS. But always be careful!
 

ash2020

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A
Trees do not really block the GPS signal that much. As stated above, if its very very dense you may have an issue. I would be more concerned about WiFi being blocked (and hence connection issues) than GPS. But always be careful!
That's interesting, I thought that the GPS would disappear. If it did happen, I would only be flying visually in amongst trees. Thanks
 

JSKCKNIT

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Thanks for that. I will do some real tests soon - if it would only stop raining!
I tested it at a secluded bay and waterfall on the Big Island. It will do exactly as mentioned above I believe when you have less than 7 or 8 GPS satellites.
 
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ash2020

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I tested it at a secluded bay and waterfall on the Big Island. It will do exactly as mentioned above I believe when you have less than 7 or 8 GPS satellites.
Thanks for that. Still raining here!
 

Moon

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Trees do not really block the GPS signal that much. As stated above, if its very very dense you may have an issue. I would be more concerned about WiFi being blocked (and hence connection issues) than GPS. But always be careful!
In my experience it really depended on the density of the tree canopy and it can take longer to get a GPS fix.

Loss of Wi-Fi signal is more of a problem so it is worth changing the settings for what happens if the connection drops. If I am flying in heavily wooded area then I change the loss of connection action to "hover" rather than RTH and it flying up and hitting the tree canopy !
 
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ash2020

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In my experience it really depended on the density of the tree canopy and it can take longer to get a GPS fix.

Loss of Wi-Fi signal is more of a problem so it is worth changing the settings for what happens if the connection drops. If I am flying in heavily wooded area then I change the loss of connection action to "hover" rather than RTH and it flying up and hitting the tree canopy !
Very good point. I will certainly do that. I wish I could remember where all the settings are. I'll get used to it, in time.
Thanks
 
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JSKCKNIT

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If I am flying in heavily wooded area then I change the loss of connection action to "hover" rather than RTH and it flying up and hitting the tree canopy !
Excellent point! Thanks for pointing that out.

P.S.
This is where I was flying. 20180803_153100-EFFECTS.jpeg
 

ManuCH

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Wouldn't it go to OPTI mode first (relying on visual cues), and only drop to ATTI mode if the visual sensors fail as well (ie. because it's too dark or with not enough contrast)?