M8N Mod Video Tutorial and Test

[Dmitry]

And as the grounded it?

 

[Dmitry]

For Pixhawk I need to change to these settings:
1. NAV5 = Airborne or Pedestrian < best for hovering.
2. PRT = Protocol out (UBX) + 38400 Baud rate.
3. RATE = 200 [ms] tot have 5Hz refresh rate.
4. SBAS = for European users sellect EGNOS.
5. CFG Save current configuration / Devices 0-BBR + 1-Flash

 

[Dmitry]

or
1. Dynamic model configured on Pedestrian (low speed and acceleration)
2. 10Hz refresh
3. SBAS On. Be sure your area is covered by SBAS
4. Static Hold 0.01 m/s
5. Baudrate to 115200

 

[Dmitry]

View attachment 3079
Same here
Secret sauce is how you do the shielding.
I re-fabbed the copper foil and grounded it.
23 sats at HDOP 0.8 was the best ever reached.

foil plant to minus? that's what you mean?

 

[Mr_Chris]

For Pixhawk I need to change to these settings:
1. NAV5 = Airborne or Pedestrian < best for hovering.
2. PRT = Protocol out (UBX) + 38400 Baud rate.
3. RATE = 200 [ms] tot have 5Hz refresh rate.
4. SBAS = for European users sellect EGNOS.
5. CFG Save current configuration / Devices 0-BBR + 1-Flash

Hmm? I just fly as normal with no changes at all and I get more sats and a more reliable lock, with slightly better HDOP readings... For me it means so far, guaranteed GPS lock in < 30 seconds but not 23sats and 0.8 or whatever.

What do the above settings accomplish for accracy / lock on Solo?

 

[fpvsteve]

foil plant to minus? that's what you mean?

Yes.

 

[fpvsteve]

Hmm? I just fly as normal with no changes at all and I get more sats and a more reliable lock, with slightly better HDOP readings... For me it means so far, guaranteed GPS lock in < 30 seconds but not 23sats and 0.8 or whatever.

What do the above settings accomplish for accracy / lock on Solo?

Arducopter sets it's own GPS params during initialization. The only parameter you should set manually is for Galileo reception along with GPS and Glonass.
# of sats, and HDOP depend on weather, time of the day, location,...
Today I had no more than 19sats and HDOP 1.2.

 

[Mr_Chris]

Arducopter sets it's own GPS params during initialization. The only parameter you should set manually is for Galileo reception along with GPS and Glonass.
# of sats, and HDOP depend on weather, time of the day, location,...
Today I had no more than 19sats and HDOP 1.2.

Sounds like I need to read up on the relevant copter variables.... If I understand you correctly, the new receiver isn't being used to its full potential until I figure out which of those parameters needs to be tweaked to what so PX4 will consider the other "constellation" of satellites...

Strange how such a significant improvement occurred without doing anything, makes me wonder why 3DR wouldn't just use the "better" radio in the first place!?

 

[Mr_Chris]

Yes.

The foil is screwed into the ground plane on the PCB, isn't it? Next time I'm in there I'll beep that to check...

 

[Mr_Chris]

Arducopter sets it's own GPS params during initialization. The only parameter you should set manually is for Galileo reception along with GPS and Glonass.
# of sats, and HDOP depend on weather, time of the day, location,...
Today I had no more than 19sats and HDOP 1.2.

I can't find those params in Tower. Not sure if I'm looking in the right place even...

 

[John Githens]

I have installed the Drotek "Ublox NEO-M8N GPS Module", and replaced the stock shield with the 3DR "Solo GPS Shield V2". I have not connected the new shield to any electrical point on the Solo. Due to my home location, I changed the SBAS parameter on the Droteck product to "WAAS". Overall, this mod appears to function as expected. After many minutes of my Solo being stationary in a field near two houses, I observed slight shifts from the Home position on Tower (or MP), and continual, slight variations in the sat and HDOP numbers. Tower also let me know about a shift from "3D" to "3D+DGPS". I started researching about GPS, DGPS, SBAS and other topics. Readers of this thread may adjust their expectations about performance of the the modified (or stock) Solo with information on this and other threads on GPS Forums. As others have mentioned, there are many factors that can affect the 3D position of a drone/UAV at power-up, at the time of launch, while it is in motion, and when it is approaching the point of launch. While it is possible to launch when the pre-launch checks are passed, it might be a good idea to wait a few more minutes for an improved position fix.

 

[fpvsteve]

I can't find those params in Tower. Not sure if I'm looking in the right place even...

The GPS settings have to be maintained in the Ublox Control center software.
Please see the links posted previously in this thread.

 

[SARDG]

The GPS settings have to be maintained in the Ublox Control center software.
Please see the links posted previously in this thread.

Hope he found them by now because Mr. Chris posted that 4 months ago...

 

[fpvsteve]

Hope he found them by now because Mr. Chris posted that 4 months ago...

Sorry my bad- Can happen if people dig out Stone Age treads ;-)

 

[SARDG]

Sorry my bad- Can happen if people dig out Stone Age treads ;-)

Quite a bit of that lately... I suppose it speaks to some folks at least using the search function - which is a good thing.

 

[John Githens]

I have installed the Drotek "Ublox NEO-M8N GPS Module", and replaced the stock shield with the 3DR "Solo GPS Shield V2". I have not connected the new shield to any electrical point on the Solo. Due to my home location, I changed the SBAS parameter on the Droteck product to "WAAS". Overall, this mod appears to function as expected. After many minutes of my Solo being stationary in a field near two houses, I observed slight shifts from the Home position on Tower (or MP), and continual, slight variations in the sat and HDOP numbers. Tower also let me know about a shift from "3D" to "3D+DGPS". I started researching about GPS, DGPS, SBAS and other topics. Readers of this thread may adjust their expectations about performance of the the modified (or stock) Solo with information on this and other threads on GPS Forums. As others have mentioned, there are many factors that can affect the 3D position of a drone/UAV at power-up, at the time of launch, while it is in motion, and when it is approaching the point of launch. While it is possible to launch when the pre-launch checks are passed, it might be a good idea to wait a few more minutes for an improved position fix.

I made 10 test flights today in a field with a slight breeze. Each flight started with placement of the Solo in the middle of a 6 foot x 6 foot pad made by CGEAR. After invoking Return To Home, the Solo auto-landed either on or partially on the mat (a minimum of two legs) at the end of each flight. GPS+DGPS. Sat locks ranged from 18 to 20. HDOP typically 0.7 - 0.9. Nice to see, however this was not a rigorous technical test (all flights within 100 feet; no programmed flights with Tower), and it was not an A-B test to compare to a Solo with the stock GPS sensor.

 

[SARDG]

I made 10 test flights today in a field with a slight breeze. Each flight started with placement of the Solo in the middle of a 6 foot x 6 foot pad made by CGEAR. After invoking Return To Home, the Solo auto-landed either on or partially on the mat (a minimum of two legs) at the end of each flight..

To paraphrase a movie... I think we're going to need a bigger pad...

 

[Mr_Chris]

Sorry my bad- Can happen if people dig out Stone Age treads ;-)

Hah! Actually I gave up. Dozens of GPS-issue-free flights later, only the latest firmware has given me pause since the M8N. Very smart people I respect have warned me though, so I do give Solo an extra update tick before flying on the first up of the session. Just ordered another Solo the other day, second backpack, everything -- loving it. [EXPLETIVE REMOVED] the bleeding edgers -- I can always buy more toys. And I already know the three I am expecting to buy from : G*, A*, or S*. Who wants to guess. One is "Ardupilot.org -- anything, but surely a PH2 or 3". Two guesses, they're easy too.