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mavic 2 GPS vs Phantom 3S

"Have you thought of consulting the manual?"

Have you thought of being less condescending?
I have read the manual and viewed videos till my monitor shut down.

It seems like everyone wants to tell me about PL. LET ME MAKE IT CLEAR. MY PL WORKS IF THE GPS GETS IT WITHIN RANGE OF THE PL. The problem appears to be that the GPS accuracy is not as good as the P3S was.

PL does not compare images at 200 ft. At that point it should be within a 5ft circle of the home point. My P3S was, the M2 is hit or miss.

Being 15-20ft horizontal of home point is not going to get it even close to a PL.

I have not tried it without PL. Next flight I will and will report how far off the GPS is. Maybe it will work better that way.

If you had read the manual then you would have seen the requirement to ascend to at least 7 meters, rather than the 5 meters that you mentioned. So no - you clearly didn't.
 
Why the GPS doesn't bring it closer to vertical is my concern because it may have contributed to a tree landing in the past.
I just need to figure out how to verify the GPS is performing as intended and doesn't have some subtle problem.
That's why I suggested you need to look into the recorded flight data to see if there really is an issue and what might be causing it.
 
I MAY have discovered the problem! But for the exercise, I am still trying to figure out how I might find this problem in the flight records.
As one might expect, if I could do something wrong, I would do it. черт that Murphy and his laws. I thought I looked into this b4 I placed my strobe lights, but I may have mistaken a thread on Mavic Pro for Mavic 2 that indicated the GPS antenna was in the tail of the AC. As it turns out I had the strobes mounted directly above the GPS antenna on top of the AC .

I have not tested it out yet, but regardless, a bad place to put the strobes.
 
Sorry mr sas... err Sar... I should have translated your signature first- then I would have taken my meter stick out to measure it instead of saying "about 5m" and given you the "FACTS". However, "So no - you clearly didn't. " there is nothing clear about it. That is just your conjecture and not a fact.
 
Sorry mr sas... err Sar... I should have translated your signature first- then I would have taken my meter stick out to measure it instead of saying "about 5m" and given you the "FACTS". However, "So no - you clearly didn't. " there is nothing clear about it. That is just your conjecture and not a fact.

I only had your statement to go by. If it was inaccurate/incorrect then that's your problem, not mine.
 
I understand, but ABOUT is "about", not "exactly". Making an issue about that is condescending and doesn't qualify as helpful. Also, PL was not the issue as I tried to be clear about.
Maybe moving the strobes will solve the GPS issue and uncover a PL issue, but I don't think so.
thanks for the conversation.
 
I understand, but ABOUT is "about", not "exactly". Making an issue about that is condescending and doesn't qualify as helpful. Also, PL was not the issue as I tried to be clear about.
Maybe moving the strobes will solve the GPS issue and uncover a PL issue, but I don't think so.
thanks for the conversation.

OK - but my suggestion to look at the manual was reasonable given what you posted. And the takeoff ascent height does make a real difference - since PL was added back into the M2 firmware there have been a number of complaints that it wasn't working, and those mostly turned out to be due to inadequate vertical ascent. When your aircraft comes back and starts to descend, does it announce that PL is initiated? If not then it wasn't triggered on takeoff. It's possible, but seems unlikely, that it's a GPS issue - inspection of the GPS data and the home point coordinates would quickly show if that is the case. And 4 or 5 meters off at the RTH location is not going to prevent it from matching the takeoff point optically. I regularly see it making those kinds of adjustments on the way down.
 
there is a difference between a
"suggestion to look at the manual"
and
"Have you thought of consulting the manual?"
If you don't understand that then you shouldn't be trying to help people.

I fully understand "the takeoff ascent height does make a real difference".
I know all the history "since PL was added back into the M2 firmware ". I have counselled others on that very topic.

Since I was flying and observed the RTH, stating "but seems unlikely, that it's a GPS issue" for an RTH that came back far outside a 5m circle of home point - when GPS spec is 2-3m circle - is not comprehending my post.

"And 4 or 5 meters off at the RTH location is not going to prevent it from matching the takeoff point optically." I haven't seen a spec on that as to the max distance and that depends on takeoff pause height. but I suspect 5m is pretty close to the limit. A return to 20m is definitely not going to do it.

when it pauses at 3m and then very slowly descends to 0.5m and stops because it is not at the home point (or close even), one can assume it is lost. At that point I had to force it to land.

PL worked perfectly some time ago.
It recently started only working occasionally.
The RTH should start its decent within 3m of home point ("<2.5m average" is the spec on GPS units like that).
15m off is not within the bell curve and is a GPS problem not a PL problem.
I am certain when I get to test this it will be back to perfect PL consistently.

I do have one question (ok maybe 2) about PL. What triggers it to record the ground picture and how do you know it has done that?
 
there is a difference between a
"suggestion to look at the manual"
and
"Have you thought of consulting the manual?"
If you don't understand that then you shouldn't be trying to help people.

I fully understand "the takeoff ascent height does make a real difference".
I know all the history "since PL was added back into the M2 firmware ". I have counselled others on that very topic.

Since I was flying and observed the RTH, stating "but seems unlikely, that it's a GPS issue" for an RTH that came back far outside a 5m circle of home point - when GPS spec is 2-3m circle - is not comprehending my post.

"And 4 or 5 meters off at the RTH location is not going to prevent it from matching the takeoff point optically." I haven't seen a spec on that as to the max distance and that depends on takeoff pause height. but I suspect 5m is pretty close to the limit. A return to 20m is definitely not going to do it.

when it pauses at 3m and then very slowly descends to 0.5m and stops because it is not at the home point (or close even), one can assume it is lost. At that point I had to force it to land.

PL worked perfectly some time ago.
It recently started only working occasionally.
The RTH should start its decent within 3m of home point (2.5m circle is the spec on GPS units like that).
15m off it a GPS problem not a PL problem.
I am certain when I get to test this it will be back to perfect PL consistently.

I do have one question (ok maybe 2) about PL. What triggers it to record the ground picture and how do you know it has done that?

I'm going to take your advice, and not try to help you. You can go and figure out the answers to those questions yourself since you are such an expert on the subject.
 
I'm going to take your advice, and not try to help you. You can go and figure out the answers to those questions yourself since you are such an expert on the subject.

Yea and it's always adorable when people modify equipment and then want to blame the designer for it's failure. Besides that, he presented the problem WITHOUT including all the variables. Basic problem solving, "everything worked perfectly and then I ___________", maybe you should undo ___________ before you blame the equipment.
 
I MAY have discovered the problem! But for the exercise, I am still trying to figure out how I might find this problem in the flight records.
As one might expect, if I could do something wrong, I would do it. черт that Murphy and his laws. I thought I looked into this b4 I placed my strobe lights, but I may have mistaken a thread on Mavic Pro for Mavic 2 that indicated the GPS antenna was in the tail of the AC. As it turns out I had the strobes mounted directly above the GPS antenna on top of the AC .

I have not tested it out yet, but regardless, a bad place to put the strobes.
The tablet .DAT will have data about the GPS including the Dilution Of Precision data. But, regardless, if there were a problem with the GPS the flight controller would know about it lower the navHealth (aka gpsHealth) to less than 4. You didn't mention any other problems so I suspect this isn't the problem.
 
The tablet .DAT will have data about the GPS including the Dilution Of Precision data. But, regardless, if there were a problem with the GPS the flight controller would know about it lower the navHealth (aka gpsHealth) to less than 4. You didn't mention any other problems so I suspect this isn't the problem.
Thanks Bud
I have processed all the DAT files. Now I need "good" plots to compare. I haven't found any tutorials on interpreting this data yet.
When I click navHealth I get this message:
Signal navHealth is empty, not plotting

I will test this in the next few days and compare the data. Maybe something will make sense to me then.
hDoP appears to change in relation to numSat which would make sense. Not sure why the numSat seems to change a lot.
 
Maybe you can post a picture of your drone and we can see if there is something that is interfering with the signal
The only thing that might have been is the strobe that was sitting on top of the GPS antenna. I moved that to the top of the nose. There is nothing else on it except for plastic landing gear and plastic eyes both taped on.
Oh, and another strobe on the bottom behind the gimble.
 
The only thing that might have been is the strobe that was sitting on top of the GPS antenna. I moved that to the top of the nose. There is nothing else on it except for plastic landing gear and plastic eyes both taped on.
Oh, and another strobe on the bottom behind the gimble.

Any pictures?
 
Thanks Bud
I have processed all the DAT files. Now I need "good" plots to compare. I haven't found any tutorials on interpreting this data yet.
When I click navHealth I get this message:
Signal navHealth is empty, not plotting

I will test this in the next few days and compare the data. Maybe something will make sense to me then.
hDoP appears to change in relation to numSat which would make sense. Not sure why the numSat seems to change a lot.
Can you provide a few of those .DATs? They're probably small enough to attach to a post.
 
the zip file is the first battery flight. I think the first RTH was dead nuts on. Don't remember how many RTH I did. The DAT file is the last of the day. I had to zip the first (too big) so I don't know if that will mess with any data.
 

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thunderdrones
the top strobe has been relocated to that position from 3" back
 

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The RTH should start its decent within 3m of home point ("<2.5m average" is the spec on GPS units like that)
Not the case on my M2Z. I usually activate RTH to show friends one of the features of the Mavic. I've done this 4 or 5 times and on occasion as the drone descends from 90 ft (the RTH setting) it appears as though the descent path will take it far from the PL spot. In the last 40 feet or so it make laterals adjustments so that it always lands close to the takeoff spot.
 
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