Drone gaining altitude on it's own

[bkushner]

New problem. Most of my issues were solved with the firmware upgrade but for the past 10 days or so getting a new issue. I start the drone, let it sit until satellites are gained then I take off. As soon as I take off and level at 50 feet or so the drone starts rising on it's OWN and Fast. Sometimes above my allowed height in Class B airspace. It raises with no hands on sticks and even with the stick down. It's completely autonomous of anything I do. It does it a few times then I'm good to go. I suspect this is something with satellites. Weird thing is it just started, only thing that's different is much colder weather...

In flight log you will see at 8 seconds I start to rise and left stick is neutral. I climb to 185 feet without touching the stick. At 32 seconds I bring the bird down to 130 feet and it starts ascending again on it's own....thanks.

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[Meta4]

I suspect this is something with satellites.

I'll see if the data shows anything, but GPS is not involved in maintaining altitude so you can rule out something to do with satellites.

 

[Victhor]

Maybe it is related with an obstacle sensors malfunction?

 

[bkushner]

Maybe it is related with an obstacle sensors malfunction?

Could be. It was a dusk flight so they were coming on and off. This is what caused my problems when I first bought the M3 but the firmware seemed to fix it by not doing that. For some reason they are coming on and off again.

 

[Meta4]

Could be. It was a dusk flight so they were coming on and off. This is what caused my problems when I first bought the M3 but the firmware seemed to fix it by not doing that. For some reason they are coming on and off again.

Altitude holding and response to throttle input was erratic for some of that flight.
Whenever the drone was climbing without being commanded to, the FlyState is shown as Gentle GPS (that's APAS or Obstacle Avoidance) which was on and off until 4:16.
After that the flight was in P-GPS for the whole time, with no more uncommanded climbing.

It looks a lot like obstacle avoidance was the cause of the unexpected behaviour.

 

[bkushner]

Altitude holding and response to throttle input was erratic for some of that flight.
Whenever the drone was climbing without being commanded to, the FlyState is shown as Gentle GPS (that's APAS or Obstacle Avoidance) which was on and off until 4:16.
After that the flight was in P-GPS for the whole time, with no more uncommanded climbing.

It looks a lot like obstacle avoidance was the cause of the unexpected behaviour.

Yeah that's what was causing issues when I first got it and haven't had any since the firmware. Before the firmware the OA was turning on and off at dusk over and over. After the update it would turn off at dusk and not come on. Wondering why it would start doing that again. I can simply manually turn off the OA and fix it..or I just had a thought...I have to check my setting. I usually have it set to STOP when encountering an obstacle vs going around. Perhaps it went back to around..I did notice recently some of my settings seemed to be different for no reason. Thanks..

 

[bkushner]

Noticed too that I'm showing WEAK GPS with 18 birds?

 

[Meta4]

Noticed too that I'm showing WEAK GPS with 18 birds?

The GPS issues are a mystery.
The drone was in the open where there should have been no obstructions to block the GPS receiver's skyview.

At 1:33.5 height = 93 ft
Sats fell from 17 to 13 anad GPS Health dropped to 2/5

At 2:28.7 height = 100 ft.
The number of sats dropped from 18 and reached 9.
GPS Health dropped to 2/5 and didn't recover until the number of sats reached 17.

The third time (4:15.9) height = 450 ft.
The number of sats stayed at 18.
But for 0.3 sec the GPS Health fell to 2/5

The number of sats seems low for a drone that receives signal from 3 satellite systems.
I'm not sure what's going on with GPS.
It would be very unusual for the number of sats to drop as much as it did the second time in a short period.
The third event is just strange.

 

[crlmjohnson]

I was flying last night right before sun set. I had issues with my obstacle avoidance on my Mavic 3 Cine. I was not able to turn the aircraft left or right with the sticks.

do anyone know what the setting should be? I have been trying different setting to try and get a feel how the drone behaves while flying.

 

[Phantomrain.org]

Noticed too that I'm showing WEAK GPS with 18 birds?

The Satellite issue is terrible, I have yet to have more the 10 too 11 Sats , but my Air 2S gets 18 to 23 instantly. The longer it takes them to release the update , the more I realize how many Problems there trying to fix.

I cant even fly over the Lake without a Rescue Jacket as i have no faith or confidence because sometimes I think its sees a Ghosts.

Phantomrain.org
Gear to fly in the Rain.

 

[Don Testme]

New problem. Most of my issues were solved with the firmware upgrade but for the past 10 days or so getting a new issue. I start the drone, let it sit until satellites are gained then I take off. As soon as I take off and level at 50 feet or so the drone starts rising on it's OWN and Fast. Sometimes above my allowed height in Class B airspace. It raises with no hands on sticks and even with the stick down. It's completely autonomous of anything I do. It does it a few times then I'm good to go. I suspect this is something with satellites. Weird thing is it just started, only thing that's different is much colder weather...

In flight log you will see at 8 seconds I start to rise and left stick is neutral. I climb to 185 feet without touching the stick. At 32 seconds I bring the bird down to 130 feet and it starts ascending again on it's own....thanks.

DJI Flight Log Viewer | Phantom Help

Upload and view flight logs from your DJI drones

www.phantomhelp.com

Mine does that too. I assume it's the obstacle avoidance sensors. DJI may have them set to avoid ground objects to an overly generous distance. It doesn't increase in elevation when I put in sport mode. Only Normal mode does that. That's why I think it's the obstacle avoidance.

 

[Desert Drone Works]

I had this issue before I returned mine. It mostly occurred at dusk when flying towards a sunset, but it also happened a few times flying over residential areas randomly. I blamed the OA system, DJI wanted me to "send it in for review/repair". It seemed to be better with it disabled.

 

[Vic Moss]

I had that issue in both of mine, but the update fixed it. If it didn't fix yours, I'd reach out to DJI and see about returning it.

 

[ianwood]

Three recent dusk flights, I had to turn off OA each time. It didn't suffer any un-commanded movements like the previous firmware but it kept hitting the brakes in clear air. One of the flights was over water during which the reported altitude went wonky about halfway into the flight. At one point, I was -53ft when I was actually around +30ft.

As for the weak GPS issue, I wonder if solutions are computed by constellation and then merged together. If you have 18 sats but not enough of any of them are in the same constellation, it could mean there is no one constellation providing enough sats for a good fix. Just a guess.

I also wonder if GPS quality gets dinged when it conflicts with what the OA system is reporting. It really shouldn't. GPS can and should be able to determine its own precision.

 

[Phantomrain.org]

Three recent dusk flights, I had to turn off OA each time. It didn't suffer any un-commanded movements like the previous firmware but it kept hitting the brakes in clear air. One of the flights was over water during which the reported altitude went wonky about halfway into the flight. At one point, I was -53ft when I was actually around +30ft.

As for the weak GPS issue, I wonder if solutions are computed by constellation and then merged together. If you have 18 sats but not enough of any of them are in the same constellation, it could mean there is no one constellation providing enough sats for a good fix. Just a guess.

I also wonder if GPS quality gets dinged when it conflicts with what the OA system is reporting. It really shouldn't. GPS can and should be able to determine its own precision.

" hitting the brakes in clear air " Those are the ghosts I am talking about , There is a problem with the GPS sats and it not anything to do with Constellation , its a wide spread problem on every forum for the M3 except those that dont know any better being that its there first drone.

Phantomrain.org
Gear to fly in the Rain and Land on the Water.

 

[db4476]

The Satellite issue is terrible, I have yet to have more the 10 too 11 Sats , but my Air 2S gets 18 to 23 instantly. The longer it takes them to release the update , the more I realize how many Problems there trying to fix.

I cant even fly over the Lake without a Rescue Jacket as i have no faith or confidence because sometimes I think its sees a Ghosts.

Phantomrain.org
Gear to fly in the Rain.

DJI recently changed the satellite constellations on certain drones, i.e. the Mavic 3. They used GPS+GLONASS+Galileo in the past but have dropped GLONASS and replaced it with GPS+Galileo+BeiDou. There is a problem with that scheme as Galileo and BeiDou share the same bands, which could cause interference for the end user. System interference, especially within E1 and E2 bands has been documented in the past. They should have stuck with GPS+GLONASS+Galileo constellations IMO or dropped Galileo for BeiDou. Just my 2 cents...

Cheers!

 

[Phantomrain.org]

China’s BeiDou satellite system more visible from space than its US rival GPS, study finds​

• Researchers say a spacecraft travelling at or below an altitude of 2,000km would be able to see 50 per cent more from the Chinese constellation
• They concluded that the most precise information could be accessed by using a combination of signals from the two navigation systems

So this is why we have lost HALF the Satellites I use to get. UGH

Im Getting use to flying with 10 , but its the wait that is very frustrating .
I no longer wait for a Home Point , I just take off and when I do that is when the Home Point is recorded. Strange how that happens.

Phantomrain.org
Gear to fly in the Rain and land on the Water. ​

 

[Meta4]

I no longer wait for a Home Point , I just take off and when I do that is when the Home Point is recorded. Strange how that happens.​

​

That's just coincidence.
Launching has nothing to do with recording a home point.
The drone will record a home point when it rates the GPS location data reliability at 4/5 or 5/5.
Your flight data would confirm that.

 

[Phantomrain.org]

That's just coincidence.
Launching has nothing to do with recording a home point.
The drone will record a home point when it rates the GPS location data reliability at 4/5 or 5/5.
Your flight data would confirm that.

Certainly something I can test out , It happens to many times for it to be just Coincidence .
I will post my results , should be interesting .

Phantomrain.org
Gear to fly in the Rain.

 

[ianwood]

There is a problem with the GPS sats and it not anything to do with Constellation

As pointed out above, the only known change to GNSS vs other recent DJI drones is one constellation swapped for another. We don't know what other changes under the covers may have been made or to what extent the the choice of constellations or number of visible sats from each has altered the end-user experience.