Air 2s, too "Satellite hungry"?

[pilifida]

Hopefully its a bug which will be solved in a future update...i knew that dji stuff is buggy next to release, but this time i jumped in )

 

[ninja_geezer]

After about 4 minutes, mine stays locked and if I land and fly within 15 minutes of the first flight, it immediately gets a gps lock and never loses it. It’s only the initial cold start. It definitely takes a lot longer than my other drones. I’ve gotten where I just sit for about 4 minutes while it’s going in and out before taking off on the first cold start of the day. Other than that, drone is great.

Spot on thats exactly what the air 2 s does why i dont know.

 

[Meta4]

That meta guy keeps on explaining how the dji pos system needs 6 sats for a lock, and how n00b i am.for explaining that i do not have a lock with 10 satelites connected , while indeed, the ol' MP needed about 6-7-8[?] sats to keep a lock

That's because you keep on and on about 10 sats with the Air 2S vs 7-8 with the MP.
You cannot compare sat numbers like that.
With GPS + Glonass + Gallileo your Air 2S has access to 71 satellites.
But with higher numbers of sats, you will get more bunched in the same parts of the sky and not improving the geometry required to provide good location data.

 

[Bobsing]

That's because you keep on and on about 10 sats with the Air 2S vs 7-8 with the MP.
You cannot compare sat numbers like that.
With GPS + Glonass + Gallileo your Air 2S has access to 71 satellites.
But with higher numbers of sats, you will get more bunched in the same parts of the sky and not improving the geometry required to provide good location data.

It's got nothing to do with 10 versus 7 or 8 satellite. It

That's because you keep on and on about 10 sats with the Air 2S vs 7-8 with the MP.
You cannot compare sat numbers like that.
With GPS + Glonass + Gallileo your Air 2S has access to 71 satellites.
But with higher numbers of sats, you will get more bunched in the same parts of the sky and not improving the geometry required to provide good location data.

It has nothing to do with 10 versus 7 or 8 satellites. It has got something to do with how long it takes to get a gps lock where you can fly safely. True, my Mavic Pro will get a gps lock with 9 satellites, but that is not what we are are talking about. It's the time it takes the Air 2s to get a stable gps lock versus my Mavic Pro, my DJI Mini 2 and my Mavic Air 2. All three of my other drones take less than a minute on a cold start to get a stable gps lock and the Dji Air 2s usually takes over 3 minutes to get a stable gps lock from a cold start. All of my test was done at the same location--same spot and same time of day. I hardly ever pay attention to the number of satellites, but I do pay attention as to when it gets a gps lock and is safe to fly. Meta 4, do you even own a Dji Air 2s??

 

[Meta4]

It's got nothing to do with 10 versus 7 or 8 satellite. It

It has nothing to do with 10 versus 7 or 8 satellites. It has got something to do with how long it takes to get a gps lock where you can fly safely.

The thread has evolved to be about time for satellite acquisition now but it wasn't earlier.
One member continues to talk about satellite numbers as if they can be compared directly and I was attempting to address that.

 

[NEWorldPhoto]

I've read this entire thread several times. It is not about how the gps system works. It is about how long it takes the Air 2s to get a gps lock so you're able to fly. I did a test with my drones at the same location and time and a cold start. My Mavic Pro took 45 seconds to get a gps lock from a cold start. I then put my Mini 2 at same location and from a cold start it took 33 seconds to get a gps lock. I then put my Air 2 at the same location and from a cold start it took 20 seconds to get a gps lock. I then put my Air 2s at the same location and from a cold start it took 3 minutes and 10 seconds to get a gps lock. All the drones kept the gps lock once it gained it, but the Air 2s. It lost the gps lock on and off up to about 4 minutes. After that, it never lost the gps lock again. So yes, the Air 2s is different. It has nothing to do with how satellites work. This was all done at same location and within 12 minutes of each other and all from a cold start.

Definitely there's a problem or bug with the A2s GPS receiver or firmware that controls the GPS acquisition, at least with some units. How in the world is it possible that THREE previous, older DJI models: the MP, Mini 2, and MA2, all of them get a GPS lock much faster than the newest A2s, and not only that, but each of these older models got progressively faster with the GPS locking time.. and now the latest, top of the line 1" sensor and most expensive A2s takes a BIG step backwards in GPS locking time??? That doesn't make sense– to improve on everything with the new model, but "downgrade" something so important like the GPS acquisition/locking performance!
And it's not only one, but SEVERAL users have reported experiencing such issue with the A2s GPS locking time, and compared it directly with those older DJI models in exactly the same place and time.
So clearly it must be a glitch or bug with the GPS receiver and/or firmware of at least a batch of units, and I think that great effort must be put to report/escalate this issue so DJI takes action to investigate and fix it, be it with a firmware update or even a replacement of the GPS receiver hardware at no charge. I think a high performance drone of such caliber should not suffer from this issue, especially compared to its predecessor, the MA2!

 

[Sjkieffer]

I agree! Takes awhile to aquire the sats! Then sometimes it loses them easier than Air 2 also

 

[ninja_geezer]

Definitely there's a problem or bug with the A2s GPS receiver or firmware that controls the GPS acquisition, at least with some units. How in the world is it possible that THREE previous, older DJI models: the MP, Mini 2, and MA2, all of them get a GPS lock much faster than the newest A2s, and not only that, but each of these older models got progressively faster with the GPS locking time.. and now the latest, top of the line 1" sensor and most expensive A2s takes a BIG step backwards in GPS locking time??? That doesn't make sense– to improve on everything with the new model, but "downgrade" something so important like the GPS acquisition/locking performance!
And it's not only one, but SEVERAL users have reported experiencing such issue with the A2s GPS locking time, and compared it directly with those older DJI models in exactly the same place and time.
So clearly it must be a glitch or bug with the GPS receiver and/or firmware of at least a batch of units, and I think that great effort must be put to report/escalate this issue so DJI takes action to investigate and fix it, be it with a firmware update or even a replacement of the GPS receiver hardware at no charge. I think a high performance drone of such caliber should not suffer from this issue, especially compared to its predecessor, the MA2!

i would like to guess they are all the same ,i have spoke to a few people and when they actually check they are the same.
some may not have noticed this ,it all depends on what you are doing when setting up ect .but yes its slow initially getting them but if you turn it off after acquiring the satellites and on again a few minutes later its very fast ! hope a firmware will speed it up ,ive flown out to quite some distance and never lost any GPS once iv acquired it as yet anyway.
a similar thread is on the DJI forum so they are aware of this issue.strange ive not seen one person mention this on youtube ....

 

[pilifida]

I agree! Takes awhile to aquire the sats! Then sometimes it loses them easier than Air 2 also

That is my problem: as i repeated 1000x times - the fact that it loses pos after a while.
And @Meta4 i do not care the sat no. But when i lose pos lock i tend to peek at the reason: how many sats are locked on the drone? And i was just baffled by the different numbers. If they implemented another "feature" - added galileo pos system, that should have been a backup or a bonus for the model not a downgrade: increasing the minimum no. of sats required for pos lock.on

 

[Meta4]

If they implemented another "feature" - added galileo pos system, that should have been a backup or a bonus for the model not a downgrade: increasing the minimum no. of sats required for pos lock.on

It's most unlikely that the minimum number to get GPS "lock" has increased.
But you will have more satellites showing on your screen display at the same time that GPS lock is achieved because there are so many more sats available.

If you really wanted to investigate that, we could check the flight data to see what the GPS data shows.

To do that...
Go to DJI Flight Log Viewer | Phantom Help
There are instructions there for how to upload the .txt file from your phone or tablet.
Phantomhelp can't read the data from DJI Fly, so just post the .txt file here.
Post a few to give more info to check.

 

[Skipper1]

If you’re having trouble locking on to satellites faster and more of them. You might want to check out the Garmin Glo 2. I’ve been flying with one for the last couple of years and has been great.

Amazon.com: Garmin GLO 2 Bluetooth GPS Receiver 010-02184-01: GPS & Navigation

Buy Garmin GLO 2 Bluetooth GPS Receiver 010-02184-01: Vehicle GPS - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

 

[Meta4]

If you’re having trouble locking on to satellites faster and more of them. You might want to check out the Garmin Glo 2. I’ve been flying with one for the last couple of years and has been great.

The Garmin device will grab satellites quickly, just like most GPS devices would.
But that's not going to do anything to assist a drone which isn't acquiring satellites promptly.

 

[ninja_geezer]

ok not flown for a few days ,went outside today, open space weather partly cloudy.
turned on Air 2 s, after startup tone i started stopwatch and watched the screen after 2 mins and 25 seconds i got a GPS lock but that was after waiting for 16 satellites to be found .once airborne after a few mins i had 26 . why oh why is it so slow to get a GPS lock after not being used for a while ,if i go back out within 15 mins its instant .way way slower than the old Air 2 i had, so this is a common issue it seems across the Air 2 s board ,lets hope DJI can sort this out with some new firmware .

 

[Meta4]

why oh why is it so slow to get a GPS lock after not being used for a while ,if i go back out within 15 mins its instant .

It doesn't explain why the Air 2S is slow in general, but how it can be slow initially and fast later is just the way GPS works.
I touched on the cold start/warm start thing early in the thread.
Here's another member explaining it:

What can cause a Mini 2 to drift up and down a few feet with only modest wind.

I was out flying my Mini 2 this weekend over a lagoon. I'd have to say no less than 10 feet or higher than 50 feet above the water. As I watched it from a distance I could see that while hovirng it would randomly move up and down 2-4 feet with hands off the sticks. I wanted to try to take it...

mavicpilots.com

 

[ninja_geezer]

It doesn't explain why the Air 2S is slow in general, but how it can be slow initially and fast later is just the way GPS works.
I touched on the cold start/warm start thing early in the thread.
Here's another member explaining it:

What can cause a Mini 2 to drift up and down a few feet with only modest wind.

I was out flying my Mini 2 this weekend over a lagoon. I'd have to say no less than 10 feet or higher than 50 feet above the water. As I watched it from a distance I could see that while hovirng it would randomly move up and down 2-4 feet with hands off the sticks. I wanted to try to take it...

mavicpilots.com

yes i have been doing some cold start testing sometimes its painfully slow nearly 3 minutes and 16 satellites ??
once acquired if you try again 20 mins later still fast ,i know for most applications not really an issue but its a backward step in a way for a newer product.

 

[pilifida]

Feel free to do whatever you want with the logs ?

 

[Macinfo]

Be interesting to see this analysis...

 

[Meta4]

Feel free to do whatever you want with the logs ?

It's always much better to have some hard data to look at and comment on.

I've looked at all three and the GPS looks bad.
What I can't tell from the data is how high the tree cover is.
If the drone is above tree cover when flying at 100 ft, the GPS performance is very bad and not reliable at all.

It would be good to see the data from a flight in open country (and away from the mountains if possible) to compare.

Here are some notes on the first flight I looked at:
Flight at 16:55

Hovering at 8 ft - sat numbers 7-9
Hovering at 25 ft - sat numbers 10-11
At 64 seconds - approximate home point set with 9 sats
Sat numbers reach 12 after climbing to 38 ft at 88 seconds
P-GPS mode after 96 seconds with 12 sats at 79 ft
But GPS quality is marginal and drops out briefly at 116 sec, 119 sec, 122 sec, 130 sec all at altitude >100 ft.
At 137 sec and 133 ft, sat numbers reach 13
At 181 sec, descended past 46 ft, sat numbers drop to 12 and lower, drone drops out of P-GPS mode.
Back in P-GPS for 5 sec at 212 sec and 24 ft.
You climbed back to 100 ft at 330 sec - 12 sats
At 345 sec 13 sats - back in P-GPS

For the whole flight, sat numbers never exceeded 13 and GPS Health never exceeded 4/5

The other two flights were similar except that sat numbers went to 17 and GPS Health was 5/5 for the first 3 minutes and then things were as bad as the other two flights.

 

[pilifida]

So, fhe conclusion: gps really sux

 

[pilifida]

Different situations: in the forest again then one open field and in a village 99% open field