Hi all,

We have 2 aircraft P4 multispectral, and both of them have a same problem, weak gps signal.

To be precisely, one of the aircraft, have maximum 14 satellite but there is constant variable between 8 and 14
and because of that aircraft have big problem to execute mission.
Second one have same problem , but capturing only 0-4 satellites.

Both crafts was updated at the current firmware v00.00.0130


Does anybody have same problem?

Thank you in advance,
Best regards

Hi vpilic, sorry for the difficultis with the drone, does the issue happen in the same place? Did you fly the drone in the open place without any obstruction? Was the compass working properly?

Hi Mindy,

Both drones is used on different places and areas. Compasses are good on both aircrafts, and both was passed calibration like they should. There wasnt any obstruction nearby, completely wide open area.
Im providing pics from one of the logs about gps signal.

https://app.airdata.com/flight/a ... 112dfaac/SENSORSGPS


As we sayd in upper post, both of aircraft have the same problem, but another one cant even start mission because capturing only 0-4 satellites.

We are 15 years in this job, and we never had problems like this before with any of DJI aircrafts, which we are working on all this years.

Strange thing is, both aircraft have same problem. We searched all other forums, sites trying to find if someone have same problems, but there is non of them about P4M.
Is this problem with aircraft, region or something else?

We will really appreciate, if you have some info about it, to share with us.

Thank you for your response.

Hi all again,

We are tested today again, and all is the same. I will provide to you logs from airdata link and one txt log directly from dji app.
airdata log
https://app.airdata.com/flight/2 ... 591910b1/SENSORSGPS

dji app log
https://drive.google.com/open?id ... p9B_9P00bMVOuvsHsRa

I will add also, for weekend we tryed 4th new aircraft, and there was same problem with satellites.

Is it possible at all, 4th aircraft in row for now, and problem still exist? We will really appreciate, if someone have any information about it?

In this case, would be nice if someone show up and say, ok Ive done some flights and everything is fine with myne, or otherwise, so we can move from dead point.
Problem exist, so we need to find solution to resolve it, because we are short with time to proceed further.

Thank you,
Best regards

vpilic Posted at 3-16 04:33
Hi all again,

We are tested today again, and all is the same. I will provide to you logs from airdata link and one txt log directly from dji app.

You need to test other models to arrive at any logical conclusion. Is it possible your location simply cannot receive GPS reliably?

Geebax Posted at 3-16 13:54
You need to test other models to arrive at any logical conclusion. Is it possible your location simply cannot receive GPS reliably?

Last 10 years we are flying at the same place with all other aircrafts, and we never had  that problem with gps. Problem is only with P4M.  All P4Ms are also tested on different locations  100-200-300 km away from our shop and problem still exist.

Hi vpilic,  we haven't tested our P4M yet, but one possible hypothesis could be a weakness in the drone project due to the fact that the "onboard D-RTK antenna" is just under the "Spectral Sunlight Sensor". This could partially shield the GNSS antenna.

Before sending back the second P4M (that one capturing only 0-4 satellites) I suggest you to upgrade the firmware ( see P4 MULTISPECTRAL Release Notes(26/03/2020)) and then compare the number of satellites sensed by the two drones at the same time and open site (on the ground).

Cheers, Maurizio

Thank you Maurizio.

We will test again after update, and we will share results with you.

Regards

Hey vpilic,
i have the same problem with two p4m. GPS (non RTK and RTK) is very weak. drops inflight sometimes to 0-3 sats. something is wrong.
not possible to fly like that missions are stopping, and also it is not safe.

any sollution?

Santiago53456 Posted at 4-10 08:40
Hey vpilic,
i have the same problem with two p4m. GPS (non RTK and RTK) is very weak. drops inflight sometimes to 0-3 sats. something is wrong.
not possible to fly like that missions are stopping, and also it is not safe.

According to our DJI source, new firmware should be released after 21st of April.
Due to the radio interferences in the environment, there is noise of satellite signal. New firmware should fix the problem by DJI software engineers who will work on some protective measures and enhancement of the GPS module, which could filter signals received from satellites and output a stable result. We are all looking for this date and solution that could resolve our problems.