Searching for GPS - Forever - and Controller Loss of Signal

[Flying Squirrel]

The honeymoon is NOT over yet ... but she is testing me.

I receive magnetic interfereance messages if I am anywhere near a structure of any type.

Solo is unable to lock up GPS - no better than 5 - if I am anywhere near my home.

That said, as long as I am in the middle of a treeless field Solo performs well. Is GPS a limiting factor here and just something I have to live with?

Controller signal ... it seems controller signal or lack there of is dependent more so on relative humidity than line of sight. I executed an early morning flight complete with sunrise and lots of dew. I flew off the curb in front of my home and it took about 5 minutes to lock on to GPS and Fly. I live in a rural area by a lake. Solo took off and I circled it around my home, climbed to 158 feet and then headed for the lake. I lost signal before I lost visual and line of sight on Solo. In this case Solo was about 600 feet out according to telemetry. On a dryer day I have made out to 1000 feet ... other days I lose signal with Solo loitering 100 feet out.

Now I cannot complain about general performance providing I keep Solo close by -- close enough to fly by visual orientation as if I were flying an RC airplane. Is what I am describing simply a Solo limitation, or do I have a problem?

I am reading about guys upgrading antennas ... wondering if GPS mods are next?? This is all fine and well but I personally would like to spend my time flying. I am looking for objectivity here and by no means am I attempting to minimize Solo's capabilities - but - Are Solo's limitations an indication I need a more advanced drone?

 

[rrmccabe]

Well it sounds like your GPS issues are not the normal ones. I get magnetic interference all the time if not careful. Need to stay away from my driveway as I have #4 rebar every 2' and that causes issues.

Guys are working on GPS mods now but I really think 3DR needs to resolve it.

I would send GPS logs to 3DR with a long acquire time. They can see on satellite map you are in the clear and should be able to see you dont get adequate satellites.

I think most GPS issues are just slow to acquire and then the occasional "glitch". Yours issue sounds different.

 

[Earldgrayjr]

I can say from experience that GPS may be a quality control issue. I had problems. Sent it in and it has bee flawless coming back. I am playing with two, and they are identical in operation, though before repair my first unit was finicky.

There are two antenna mods that i know of (DBSMODS and FPVLR) and I believe both work well. I have FPVLR and it doubled my signal.

One of the beauties of open source is the mod options. There are already GPS and WiFi mods for Solo, though they are not for the squeemish and are definately DIY at this point. I know some are contemplating business opportunities in that area, but that will likely be a while, as stock unit requirements and QC are sorted out.

One of the things you can do is look at the other side. That is to say, look at the WiFi and GPS environments. It is possible that Solo is OK as is, and you just have a tough environment. I am often surprised at the results of sniffing in this area.

I use GPS Test and WiFi Analyser, though there are many free apps in both categories... You can look at these and see both environemnts from another device to compare with Solo. It is useful to put the tablet close by the drone and at the same elevation to get a good comparison. Keep in mind, that number of sats is not the only number to look at. Where they are in relation to the craft is important, as it needs 3D triangulation to have good position.

Another option for GPS (depending on the actual problem) is to take off in manual, and when you get higher up and away from reflections and obstructions, flip to FLY

Hope it helps

 

[Leafy]

The GPS on mine is really only usable in open areas. Like in the middle of nowhere open. I fly in manual mode ever since it locked up and I watched it drift into a bush. I can take a Pixhawk with an M8N and get a 3d lock with 15 satellites in less than 30 seconds on the first floor of a 2 story brick house surrounded by huge trees. The Solo won't even pick up 1 satellite when I put it in the same place. It needs to be fixed or for me the gimbal isn't worth buying.

 

[Earldgrayjr]

The Pixhawk is s not the GPS, but something is wrong. I would call 3dr. I did, and had a quick turn around.

 

[SteveMyers75]

The Pixhawk is s not the GPS, but something is wrong. I would call 3dr. I did, and had a quick turn around.

Leafy is correct about the NEO-M8N locking onto SATs substantially faster than the stock NEO-7N in a Solo.

It is also much more precise in PDOP, making the Solo a much more accurate flyer.
Positional drift was in the 8~10 feet radius with 7N, less than 4 feet with M8N
RTL showed the same result as drift.

I also think 3DR has an issue with the plastic used for the covers and the metal spring used on the battery latch right above the passive patch antenna. (maybe the proto/test units used better materials and no spring?)

If I ever decide to get another Solo, I already have a M8N with a re-located active patch rig ready to swap right in.
I'll most likely wait until someone who went beyond the 30 Day RP posts one up for cheap on eBay...

 

[Leafy]

The Pixhawk is s not the GPS, but something is wrong. I would call 3dr. I did, and had a quick turn around.

The Pixhawk is a flight controller, so your right it's not a GPS

 

[Leafy]

Leafy is correct about the NEO-M8N locking onto SATs substantially faster than the stock NEO-7N in a Solo.

It is also much more precise in PDOP, making the Solo a much more accurate flyer.
Positional drift was in the 8~10 feet radius with 7N, less than 4 feet with M8N
RTL showed the same result as drift.

I also think 3DR has an issue with the plastic used for the covers and the metal spring used on the battery latch right above the passive patch antenna. (maybe the proto/test units used better materials and no spring?)

If I ever decide to get another Solo, I already have a M8N with a re-located active patch rig ready to swap right in.
I'll most likely wait until someone who went beyond the 30 Day RP posts one up for cheap on eBay...

I have not taken my Solo apart yet, but would it be difficult to move the GPS onto the top of the cover?

 

[SteveMyers75]

I have not taken my Solo apart yet, but would it be difficult to move the GPS onto the top of the cover?

Difficult, no.
Aesthetically ugly, yes.

The cable is plenty long enough to move it around about 2 inches either side of the battery/case split.
There are slots in the GPS module mount wide enough to slide the connector through, no problem.

I actually tested it tie-wrapped to the top of the module mount, just in front of the battery latch mechanism with the passive path antenna pointing to a clear sky.(No GPS Cover)
It did work better, but no where near as good as the M8N/Active patch setup.

I never felt comfortable hovering the Solo at just above "Head-Height" near me with the 7N, but I was OK with it when I used the M8N.

 

[Earldgrayjr]

Difficult, no.
Aesthetically ugly, yes.

The cable is plenty long enough to move it around about 2 inches either side of the battery/case split.
There are slots in the GPS module mount wide enough to slide the connector through, no problem.

I actually tested it tie-wrapped to the top of the module mount, just in front of the battery latch mechanism with the passive path antenna pointing to a clear sky.(No GPS Cover)
It did work better, but no where near as good as the M8N/Active patch setup.

I never felt comfortable hovering the Solo at just above "Head-Height" near me with the 7N, but I was OK with it when I used the M8N.

Interesting that I had problems with the first. No problems with the second (10 data low hdop etc. in about 1 minute) and neighbors across the street is identical, locking within a few seconds of the other. Once in the air, they both have 12+ etc.

 

[Leafy]

Difficult, no.
Aesthetically ugly, yes.

The cable is plenty long enough to move it around about 2 inches either side of the battery/case split.
There are slots in the GPS module mount wide enough to slide the connector through, no problem.

I actually tested it tie-wrapped to the top of the module mount, just in front of the battery latch mechanism with the passive path antenna pointing to a clear sky.(No GPS Cover)
It did work better, but no where near as good as the M8N/Active patch setup.

I never felt comfortable hovering the Solo at just above "Head-Height" near me with the 7N, but I was OK with it when I used the M8N.

Have you flown your Solo with an M8N GPS installed because I don't feel comfortable with the current GPS either?

 

[Earldgrayjr]

Have you flown your Solo with an M8N GPS installed because I don't feel comfortable with the current GPS either?

There is a how to video posted here today on how to change it. Pretty simple...

 

[SteveMyers75]

Have you flown your Solo with an M8N GPS installed because I don't feel comfortable with the current GPS either?

Yes, you can read about it here.

http://www.3drpilots.com/threads/so...ctive-patch-antenna-test.544/page-3#post-8749

 

[onthewave]

I can say from experience that GPS may be a quality control issue. I had problems. Sent it in and it has bee flawless coming back. I am playing with two, and they are identical in operation, though before repair my first unit was finicky.

There are two antenna mods that i know of (DBSMODS and FPVLR) and I believe both work well. I have FPVLR and it doubled my signal.

One of the beauties of open source is the mod options. There are already GPS and WiFi mods for Solo, though they are not for the squeemish and are definately DIY at this point. I know some are contemplating business opportunities in that area, but that will likely be a while, as stock unit requirements and QC are sorted out.

One of the things you can do is look at the other side. That is to say, look at the WiFi and GPS environments. It is possible that Solo is OK as is, and you just have a tough environment. I am often surprised at the results of sniffing in this area.

I use GPS Test and WiFi Analyser, though there are many free apps in both categories... You can look at these and see both environemnts from another device to compare with Solo. It is useful to put the tablet close by the drone and at the same elevation to get a good comparison. Keep in mind, that number of sats is not the only number to look at. Where they are in relation to the craft is important, as it needs 3D triangulation to have good position.

Another option for GPS (depending on the actual problem) is to take off in manual, and when you get higher up and away from reflections and obstructions, flip to FLY

Hope it helps

OK I actually put my Inspire1 side by side to the SOLO and the Inspire acquired GPS in 40 seconds while the SOLO kept going in and out including Magnetic interference and finally after almost 4 minutes locked on GPS? Concrete surface with rebar in there too. What is the quickest setting or method to takeoff without GPS lock? Just keep holding down the FLY button? Sometimes you just need to get in the air within a couple minutes and I have noticed that the SOLO just takes a lot longer to get ready in general, pre-flight and all. GPS has yet to lock quicker than 2 minutes...I know I know never rush but sometimes 2 minutes is 30 seconds too long to get the shot.

 

[Jubalr]

Quickest way to get in the air is to put it in manual mode. You will need to hold the throttle down, press manual, then hold Fly as usual. It is still very stable and will hold altitude.

 

[Earldgrayjr]

You can also program one of youe A/B buttons to be Manual. I have done that for quick access if problems arise

 

[Ian [P13]]

Note: The PDOP reading is soon to be HDOP as it should be (fixed in Arducopter recently so will eventually make it to Solo)...

https://github.com/diydrones/ardupilot/pull/2462

The H/PDOP reading isn't that important to Arducopter Solo now (it's only used for the pre-arm), the sAcc (speed accuracy) is now the figure used to determine the reliability of the GPS.

The Arducopter bug for the M8N stuttering has recently been closed which is good news.

 

[Earldgrayjr]

Note: The PDOP reading is soon to be HDOP as it should be (fixed in Arducopter recently so will eventually make it to Solo)...

https://github.com/diydrones/ardupilot/pull/2462

The H/PDOP reading isn't that important to Arducopter Solo now (it's only used for the pre-arm), the sAcc (speed accuracy) is now the figure used to determine the reliability of the GPS.

The Arducopter bug for the M8N stuttering has recently been closed which is good news.

Does this cover the land and long wait for reaquire issue a few are having?

 

[Ian [P13]]

The sAcc (speed accuracy) must be good for take off as well, but you can't see the value, so if someone is seeing HDOP below 2.5 and scratching their head about why they can't take off then that is the reason why. If this ever happens either wait longer, relocate the Solo, or take off in manual and switch into GPS once at a sufficient height.

If anyone is getting 0 GPS and it NEVER climbs to even 1 or more, then that is a fault, provided of course they're on firmware 1.5 at least and have power cycled at least a few times after the firmware update.

I know from this group and elsewhere, some people are upgrading to the M8N. The M8N having a wideband antenna is susceptible to noise, so even with the copper shielding I do wonder if it's wise having it in the same location as it's mere centimeters away from the Pixhawk and not all that far away from the GoPro. I know 3DR don't even sell an external M8N, they definitely do not appear fond of it, but I know some Pixhawk users who have had them on masts even for 100's of hours and seem perfectly happy with it... I would have strictly advised against an M8N only days ago as there was an open bug against it in Arducopter but that bug is now closed.

The fact DJI uses the M8N doesn't reassure me as their testing comes across as being generally crap, DJI have had to be forced into acknowledging errors such as magnetic declination in the past, so I doubt they would ever make it public if they ever did find any issues with the GPS. On the other hand there are a lot of P3 and Inspire users and I don't think GPS is a gripe...

It's not yet widely available from what I can see, but I understand the LEA-8T is considered a good GPS upgrade, given the lack of availability of that, personally I'm trying a NEO-7N on a mast and if that does the job I'll be happy. I'd add to that I've never had a true problem with the Solo GPS, but if I can reduce the time needed to get a lock that would be a bonus.

So that's my entire 2p on GPS...

 

[onthewave]

No matter what I do the SOLO will not initialize from a moving platform like the boat we were trying to launch it from. It has no DYNAMIC HOME POINT capability at this time. AS far as I can testify to no other drone we have owned has had this problem. If you have a FLY MANUAL mode then it should FLY no matter what. Not the case with their firmware and ARDUPILOT coding. Waited over 4 months for the Gimbal too so we tossed in the towel and returned it. It's a tool like other drones but the features or lack of in our case made it the wrong tool. I will say it is a beautifully crafted and portable and easily repairable platform compared to the Inspire, any crash and you're out a carbon fiber arm and 6 weeks to repair, truly a bummer. When SOLO is all said and done and the features are functional and gimbal shipping we will re-visit.