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Had a little glitch with my anafi today

ufosaboveus

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So I was out at our hunting cabin just checking on things. As my luck has been lately, it was windy and cloudy but I still wanted to at least take the Anafi up for a quick look around. Everything looked good when I took off but once I was up about 50 feet, I lost GPS signal. I was able to fly it back no problem so not a big deal really. I was wondering why it would have lost signal so close to me and I guess it had to do with all the clouds I had today. So that got me wondering how often are others losing GPS when flying in heavy cloud cover? This was first time in over 20 flights it had happened to me. What about the rest of you?
 
This day was heavily overcast and raining. My Anafi, iPad and Samsung phone had weak to no GPS signal so mostly manual flight.

 
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Hi. I've no idea what caused your problem I'm afraid but I do know a bit about GPS, and I can tell you that GPS signals are not affected by cloud cover (the frequency used is not attenuated by clouds). This makes sense if you think about it - if GPS reception were affected by weather then it woudn't really be fit for the purpose for which it was designed (military grade navigation anywhere in the world).

Similarly the distance between the drone and you would make no difference - the drone has a GPS receiver, and your phone has a GPS receiver. Both are listening to the same satellite broadcasts, but they are completely independent of one another. Similarly, GPS is separate from and independent of the WiFi connection between your controller and the drone.

Hope that's helpful, and hope you get to the bottom of the issue.

Cheers
 
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Hi. I've no idea what caused your problem I'm afraid but I do know a bit about GPS, and I can tell you that GPS signals are not affected by cloud cover (the frequency used is not attenuated by clouds). This makes sense if you think about it - if GPS reception were affected by weather then it woudn't really be fit for the purpose for which it was designed (military grade navigation anywhere in the world).

Similarly the distance between the drone and you would make no difference - the drone has a GPS receiver, and your phone has a GPS receiver. Both are listening to the same satellite broadcasts, but they are completely independent of one another. Similarly, GPS is separate from and independent of the WiFi connection between your controller and the drone.

Hope that's helpful, and hope you get to the bottom of the issue.

Cheers

I agree clouds have nothing to do with weak GPS but I can say the last 2 weeks people have been having problems getting a good lock. This could be because of the Est. Sats Locked. I have seen it around 11 & 12 during this time and have had a hard time getting a lock with the Anafi.

Opera Snapshot_2019-01-23_073827_www.uavforecast.com.png
 
I turn on my Anafi first and then set up everything else. Rarely is it not locked in when the app is ready.
 
Re losing the GPS signal, it was the first and only time it has happened to me in over 20 flights so far. Was not a big issue as I mentioned... I was still in control of the drone but I landed anyway just to be safe. Thought i'd share my experience here as we are all building a good network of information on our great little drones.
 
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My reply was not about losing GPS as I have never lost it either. It was having a hard time getting a good lock on the Anafi GPS before flight.
I have occasionally also observed the following - never get GPS whilst sitting on the ground - takeoff to three feet and immediately the Anafi GPS goes green. Land straight away and the Anafi GPS turns back to red? This has happened in several locations.
 
I have had my GPS signal suddenly get lost but then it is locked on again.
Doesn't happen very often but it has happened and I am not sure why.
One of those technical hiccups.
 
I have occasionally also observed the following - never get GPS whilst sitting on the ground - takeoff to three feet and immediately the Anafi GPS goes green. Land straight away and the Anafi GPS turns back to red? This has happened in several locations.

that is strange! i wont take off unless the GPS is green because it drifts to much without the GPS lock.
 
that is strange! i wont take off unless the GPS is green because it drifts to much without the GPS lock.
What mainly concerns me is the switching back to red when landing. This hints at two possible scenarios:
1) The Anafi once up and flying will relax it's satellite requirements in order to provide some form of GPS stabilisation or
2) There is something affecting the GPS signal when on the ground.

I guess the second option is not that concerning - except you may miss a video opportunity while waiting for GPS lock.
 
Rain and clouds have no effect on GPS. Only hard obstructions like trees or buildings can reduce accuracy. Was the drone over tree tops when you lost signal?
After my incident with a drone eating tree last week, I researched this quite thoroughly & one of the many sites I looked at said this about GPS:
GPS requires a direct line of sight between the receiver and the satellite. When an object lies within the direct path, accuracy suffers due to reflections and weakening of signals. This is particularly problematic in urban environments, within valleys and on mountain slopes. In all three situations, the objects (buildings and the Earth itself) are substantial enough to completely block the GPS signals. When weak signals are received, they may have been reflected off buildings and the surrounding landscape. Reflections generate multi-path signals arriving with a small time delay at the receiver. This results in inaccurately calculated position.

Even when the object is less substantial (tree cover, car roof, your body), reflection and weakening of signals may still occur. This can sometimes be observed when viewing your recorded GPS track logs on top of aerial imagery. In the image on the left, the true position of the footpath follows the shadowy area in the forest. However, as the GPS receiver enters the forest (walking from east to west), it can be observed that reflections cause the recorded track to incorrectly shift slightly to the south.

When carrying a GPS device, generally, the higher the antenna is fixed, the better the reception. Good positions include the shoulder strap or the top pocket of a backpack, mounted on top of a cycle helmet, or a roof antenna on a car.
Source: Accuracy of GPS data - OpenStreetMap Wiki
 

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