P4PV2.0

[OzoneTech]

My P4PV2 has unstable satellites logging on an overcast day. I was on top of a 45m tall building. Satellites logged were 4-8. Some times it goes to 10 and drops back to 4. Is it normal for such behavior on overcast days? At times the drone holds position and won't move with full throttle.

 

[Starz]

Anything attached to the bottom section that may be interfering with the obstacle avoidance system? Satellite acquisition may be a gps module issue. I have noticed with overcast, satellite acquisition can take a bit longer.

 

[OzoneTech]

Anything attached to the bottom section that may be interfering with the obstacle avoidance system? Satellite acquisition may be a gps module issue. I have noticed with overcast, satellite acquisition can take a bit longer.

No. I do not have any thing attached to the bottom of the AC. But I do have RID attached on top of the drone as per local (Singapore) regulations.

 

[MapMaker53]

I've specifically tested to see if my RID module attached to the top of my P4P_v1 shell will interfere with GPS -- and it absolutely does. Significantly. I don't know why Singapore specifically wants it mounted on top of drones, but I suspect most pilots will ultimately choose to mounting it elsewhere to allow a strong GPS signal.

Just fire up your drone on the ground with the RID unit on top and wait for the satellite count. Then remove the RID unit and watch the satellite count go up. It has nothing to do with cloud cover.

 

[ArnoldLeVine]

Does the recent firmware upgrade for your P4Pro V2 (and it looks like you also have an RTK) eliminate the need for a module in Singapore?

 

[Starz]

Exactly the WRONG place to put that gigantic thing.

 

[OzoneTech]

I've specifically tested to see if my RID module attached to the top of my P4P_v1 shell will interfere with GPS -- and it absolutely does. Significantly. I don't know why Singapore specifically wants it mounted on top of drones, but I suspect most pilots will ultimately choose to mounting it elsewhere to allow a strong GPS signal.

Just fire up your drone on the ground with the RID unit on top and wait for the satellite count. Then remove the RID unit and watch the satellite count go up. It has nothing to do with cloud cover.

Thanks. I shall relocate the RID and post the outcome.

 

[OzoneTech]

Does the recent firmware upgrade for your P4Pro V2 (and it looks like you also have an RTK) eliminate the need for a module in Singapore?

I have checked with the Civil Aviation (CAAS) department. They are working on it to see if the RID module can be removed from drones transmitting RID. As of now we have to use it till CAAS changes the regulations.

 

[Capt KO]

Shows how uninformed some agencies that write the regs are. My P4P RID is attached to a rear leg and works perfect.

 

[OzoneTech]

Shows how uninformed some agencies that write the regs are. My P4P RID is attached to a rear leg and works perfect.
View attachment 125660

On Phantom both front and rear legs carry antennas. Will it not interfere?

 

[OzoneTech]

Thanks. I shall relocate the RID and post the outcome.

I relocated the RID and the problem persists.

 

[Capt KO]

On Phantom both front and rear legs carry antennas. Will it not interfere?

I was instructed to install my mount on lower rear legs and have no interference. Another posted a mount location between rear legs with a 3D printed mount shown. If your GPS works with no RID attached, your RID unit seems to be at fault.

 

[OzoneTech]

I was instructed to install my mount on lower rear legs and have no interference. Another posted a mount location between rear legs with a 3D printed mount shown. If your GPS works with no RID attached, your RID unit seems to be at fault.

As long as there is no interference, I am fine with mounting location. The RID is working fine since it can be located. I will be testing the P4PV2 at a different location to check if it due to any other interference causing GPS to remain unstable.

 

[Meta4]

My P4PV2 has unstable satellites logging on an overcast day. I was on top of a 45m tall building. Satellites logged were 4-8. Some times it goes to 10 and drops back to 4. Is it normal for such behavior on overcast days?

Cloud cover has zero effect on GPS reception.
If the drone is out in th eopen with a clear view of most of the sky, it should be receiving 15-20 or even more sats.
If yours is out in the open with a full sky view, the numbers you mention suggest something else is causing the problem.

At times the drone holds position and won't move with full throttle.

Without more information or seeing flight data, it's hard to tell what's causing that, but it's not at all related to GPS.

 

[OzoneTech]

Cloud cover has zero effect on GPS reception.
If the drone is out in th eopen with a clear view of most of the sky, it should be receiving 15-20 or even more sats.
If yours is out in the open with a full sky view, the numbers you mention suggest something else is causing the problem.

Without more information or seeing flight data, it's hard to tell what's causing that, but it's not at all related to GPS.

Where can I find the flight data?

 

[Meta4]

Where can I find the flight data?

Here are a couple of options ...

1. Go to DJI Flight Log Viewer | Phantom Help
Follow the instructions there to upload your flight record which is in your phone or tablet.
That will give you a detailed report on the flight data.
Come back and post a link to the report it provides and someone might be able to analyse it and give you an understanding of the cause of the incident.
or
2. Just post the .txt file here
or
3. If you use Airdata, you can view the flight data on Airdata and post a link for the Airdata report

 

[OzoneTech]

Here are a couple of options ...

1. Go to DJI Flight Log Viewer | Phantom Help
Follow the instructions there to upload your flight record which is in your phone or tablet.
That will give you a detailed report on the flight data.
Come back and post a link to the report it provides and someone might be able to analyse it and give you an understanding of the cause of the incident.
or
2. Just post the .txt file here
or
3. If you use Airdata, you can view the flight data on Airdata and post a link for the Airdata report

DJI Flight Log Viewer | Phantom Help

Upload and view flight logs from your DJI drones

www.phantomhelp.com

Here is the sharing link:



To view, edit or delete your shares:

My Shares

 

[Meta4]

My P4PV2 has unstable satellites logging on an overcast day. I was on top of a 45m tall building. Satellites logged were 4-8. Some times it goes to 10 and drops back to 4. Is it normal for such behavior on overcast days?

Your GPS count went as high as 10-11 for only 6 or 7 seconds during the flight.
That is quite a bit lower than a P4 pro should receive if it's got a clear view of most of the sky and you haven't mounted an accessory on top of the GPS antenna.
Singapore is a very vertical city with tall buildings blocking much of the sky in amny places.
If you were in one of those areas where the sky is blocked, you could try taking the drone somewhere out in the open like Marina Barrage or East Coast Park and see if that makes a difference.

At times the drone holds position and won't move with full throttle.

Your Phantom's height will be limited if GPS reception is poor.
Height is restricted to 26 feet (8 meters) when the GPS signal is weak and Vision Positioning is activated.
Height is restricted to 98 feet (30 meters) when the GPS signal is weak and Vision Positioning is turned off.

 

[OzoneTech]

Your GPS count went as high as 10-11 for only 6 or 7 seconds during the flight.
That is quite a bit lower than a P4 pro should receive if it's got a clear view of most of the sky and you haven't mounted an accessory on top of the GPS antenna.
Singapore is a very vertical city with tall buildings blocking much of the sky in amny places.
If you were in one of those areas where the sky is blocked, you could try taking the drone somewhere out in the open like Marina Barrage or East Coast Park and see if that makes a difference.



Your Phantom's height will be limited if GPS reception is poor.
Height is restricted to 26 feet (8 meters) when the GPS signal is weak and Vision Positioning is activated.
Height is restricted to 98 feet (30 meters) when the GPS signal is weak and Vision Positioning is turned off.

Thank you for the analysis. I have flown the Phantom both at the Marina Barrage and West Coast and have had no issues with GPS. In the last picture I find some antennas on the roof not accessible from the terrace. I am checking if any high-power broadcasting is interfering with the GPS.

 

[OzoneTech]

Thank you for the analysis. I have flown the Phantom both at the Marina Barrage and West Coast and have had no issues with GPS. In the last picture I find some antennas on the roof not accessible from the terrace. I am checking if any high-power broadcasting is interfering with the GPS.

This day I did test flights with the P4PV2 at a different location. I could consistently lock 15 GPS satellites in 5 test flights. Regarding the RID mounted on top of the P4PV2 there was a drop in satellite of 1-2 only, i.e., I could consistently lock 12-14 GPS.