That’s it. First 4 are the usual +5V TX RX Gnd, the next two are for the onboard security chip, and are read by the Inspire to check the GPS is genuine DJI unit, and the last two go to free pads that don’t have anything soldered on them.
Awesome thanks man
I will keep it in mind if the glitch remains a problem. Batteries are charging now
I have also been struggling with gps glitches for a while. I suspect that the 3D speed reported by the gps is the problem. Looking at my logs the gps position looks more realistic than the estimation from the fc.
Running 4.1dev and bn-880 gps.
Tonight I found this m9n alternative, https://store-drotek.com/917-DP0801.html
Have ordered one to see if there will be any difference.
Anyone having experience with it?
Hi!
Started with arducopter some months ago, but keep having problems with GPS glitches. Now I rebuilt the frame to separate GPS for all electronic, but no help.
From previous evaluation I think it’s not really caused by GPS, but more with the compass variance. Is it common?
My quad is powered with LiIon battery which is magnetic and even I do my best to separate it from compass, it’s impossible to avoid compas influence. Ardupilot some way can automaticaly compensate compass inacuracy so after few initial “toilet bowl” circles in LOITER copter settles down and holds position OK, but I have problems in RTL at bigger distances and altitudes, where copter keeps LOITERing instead of RTL while slowly gaining altitude (see in attached log between times 12:44:29 and 12:45:07)
Current GPS and compass is BN-880, before I tested completely different one and problem was the same.
My log is here: https://drive.google.com/file/d/128ycNJe3MfOS6EOLZJayCY-nmL_JlrUP/view?usp=sharing
Any ideas, advices or even further questions wellcome!
Thanks!
Hi Roman
I am no expert in GPS…there are a number of guys on this forum that are far greater experts then I. But I have one observation I can share… That is the BN-880 GPS…I had one and had to toss it…GPS glitches.
Also @Patrik_Emilsson is also having the same issues on the BN-880 GPS…so it’s something to consider.
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Hi Patrik, I am testing the m9n:
[Edit]
I raised an issue:
Ricky, thanks for the idea, but previously I had the same experience with different GR-BD GPS ( https://images.app.goo.gl/kZMoDQiM5QAFjQZv8 ) and in the flight log are very strange messages like “EKFINAV FAILSAFE: OCCURED OR FAILED TO INITILIASE” so it seems to be something deeper. Great would be if there is someone with deep understanding of internal software process and looked into my logfile - maybe the answer can be found there…
Hey Roman
I get the same messages when my machine first loads up. It appears that it needs a minute or two to settle before I arm it. If I arm it right away when there are enough sats. I get the error.
IF I wait a minute and then try I don’t get the error and I am free to fly.
Here is a log snippet, basically on this flight I bunged the battery in and immediately tried to arm it. I could see in QGC that there where 16 sats so i figured I was good to go…ah nope.
However all the other flights where I waited for a minute had no such errors.
- ERRORS * TIME Subsys ECode Description
- 19:00:26 16 2 EKF CHECK: EKF CHECK BAD VARIANCE
- 19:00:26 17 1 EKFINAV FAILSAFE: OCCURED OR FAILED TO INITILIASE
- 19:00:29 17 0 EKFINAV FAILSAFE: ERROR RESOLVED/CLEARED
- 19:00:37 24 1 EKF PRIMARY: OCCURED OR FAILED TO INITILIASE
- 19:00:37 16 2 EKF CHECK: EKF CHECK BAD VARIANCE
- 19:00:37 17 1 EKFINAV FAILSAFE: OCCURED OR FAILED TO INITILIASE
- 19:00:42 24 0 EKF PRIMARY: ERROR RESOLVED/CLEARED
- 19:00:42 17 0 EKFINAV FAILSAFE: ERROR RESOLVED/CLEARED
My vehicle booted up at 12:35:14 and I armed and airborne at 12:36:49 with 14 locked satellites, but as you can see below, errors were coming repeatedly much later.
12:38:27 24 1 EKF PRIMARY: OCCURED OR FAILED TO INITILIASE
12:38:31 16 2 EKF CHECK: EKF CHECK BAD VARIANCE
12:38:31 17 1 EKFINAV FAILSAFE: OCCURED OR FAILED TO INITILIASE
12:38:32 11 2 GPS: GPS GLITCH
12:38:41 16 0 EKF CHECK: EKF CHECK VARIANCE CLEARED
12:38:41 17 0 EKFINAV FAILSAFE: ERROR RESOLVED/CLEARED
12:38:49 11 0 GPS: ERROR RESOLVED/CLEARED
12:40:47 16 2 EKF CHECK: EKF CHECK BAD VARIANCE
12:40:47 17 1 EKFINAV FAILSAFE: OCCURED OR FAILED TO INITILIASE
12:40:47 11 2 GPS: GPS GLITCH
12:40:54 16 0 EKF CHECK: EKF CHECK VARIANCE CLEARED
12:40:54 17 0 EKFINAV FAILSAFE: ERROR RESOLVED/CLEARED
12:41:03 11 0 GPS: ERROR RESOLVED/CLEARED
12:42:06 16 2 EKF CHECK: EKF CHECK BAD VARIANCE
12:42:06 17 1 EKFINAV FAILSAFE: OCCURED OR FAILED TO INITILIASE
12:42:06 11 2 GPS: GPS GLITCH
12:42:15 16 0 EKF CHECK: EKF CHECK VARIANCE CLEARED
12:42:15 17 0 EKFINAV FAILSAFE: ERROR RESOLVED/CLEARED
12:42:23 11 0 GPS: ERROR RESOLVED/CLEARED
12:42:50 16 2 EKF CHECK: EKF CHECK BAD VARIANCE
12:42:50 17 1 EKFINAV FAILSAFE: OCCURED OR FAILED TO INITILIASE
12:42:52 16 0 EKF CHECK: EKF CHECK VARIANCE CLEARED
12:42:52 17 0 EKFINAV FAILSAFE: ERROR RESOLVED/CLEARED
12:43:23 16 2 EKF CHECK: EKF CHECK BAD VARIANCE
12:43:23 17 1 EKFINAV FAILSAFE: OCCURED OR FAILED TO INITILIASE
12:43:24 11 2 GPS: GPS GLITCH
12:44:08 16 0 EKF CHECK: EKF CHECK VARIANCE CLEARED
12:44:08 17 0 EKFINAV FAILSAFE: ERROR RESOLVED/CLEARED
12:44:13 16 2 EKF CHECK: EKF CHECK BAD VARIANCE
12:44:13 17 1 EKFINAV FAILSAFE: OCCURED OR FAILED TO INITILIASE
12:44:17 29 1 : OCCURED OR FAILED TO INITILIASE
12:44:22 10 5 FLIGHT MODE: VEHICLE WAS UNABLE TO ENTER FLIGHT MODE LOITER
12:44:22 24 0 EKF PRIMARY: ERROR RESOLVED/CLEARED
12:44:23 16 0 EKF CHECK: EKF CHECK VARIANCE CLEARED
12:44:23 17 0 EKFINAV FAILSAFE: ERROR RESOLVED/CLEARED
12:44:26 11 0 GPS: ERROR RESOLVED/CLEARED
12:44:38 29 0 : ERROR RESOLVED/CLEARED
I think it’s something else than GPS but don’t know what to test next.
Hi, have now got a chance to test this GPS on my quad and I also had issues with the auto configuration. Did it manually in Ublox config tool and turned off auto config in ArduCopter. The result is fantastic I got 30satelites today and hdop of 0.47!
Have not seen any glitches in my log anymore so I’m very happy. I guess one reason for the better reception is the much bigger antenna, approx 4times the size compared to 880GPS
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Hey Patrick which GPS are you referring to.
Might be time to go shopping.
Hi,
This one from Drotek with Ublox M9N
So far very happy with the performance, though a little troublesome setting it up.
I can help if you go for it and get into trouble.
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Thanks Patrick. Do yo have teh dimensions of the GPS unit as a whole. She looks large. Space is a bit of a concern on my two drones…that said…GPS glitches are ticking me off.
Hi guys,
just wanted to add, that I discovered my GPS glitches are caused by vibrations and have nothing to do with GPS.
When I fly slowly, vibrations are weak and IMU position corresponds to GPS position. Once I start fly fast (for my 9’’ quad it’s about over 45km/h) vibrations increases and disturbs IMU readings the way that position became inacurate. Then there is inconsistency betwen IMU and GPS position (even it’s correct) and GPS glitches are reported. May be usefull to know for you…
Roman
Good to know Roman.
Unfortunately in my case I get the glitch the minute I arm the bird. I disarm it and it clears, I arm it it glitches. I wait a minute it clears and I can arm. I then may get a glitch while flying…not as often…but from time to time. However I do have issues with Vibrations…so I will look into it. Anything to improve on it’s performance.
PCB is 50x50mm, approx 10mm thick.
I have printed a ABS box for it and on my 10" prop quad it fits pretty good.
You up for sharing the file.
I think I might go the same way.
Yea no problem, you might want to tweak it a little.
You want the print files or CAD files, or both? I made it in Fusion 360
The cad…or STL is fine. I can tweak if needed.
I just need to deal with this glitch issue. I had an RTL the other day that had a glitch a few feet off the ground. IT nearly hit a small building. Not that the building would have suffered but the drone would have gotten bruised up a bit. I have had 4 crashes so far with this thing. I am trying to beat out the bugs.
Yea I know how that is, have been struggling with that for a long time too.
Every flight before had at least a few glitches some barely noticeable some major. Just two flights tested yet but not glitches at all so far. I will pack the files and share.