Anyone lost gps fix with the Mro upgrade yet

Rotorboy2.4gh · Dec 21, 2017

As I stated in my post, I use those tools already. I am an experienced apm/pixhawk pilot. I am a rc hell pilot for over 25-30 years. I can fly. The point here again is, I've personally have never had this happen before with a m8n on a mast. But I'm hearing that solo locks out because of other sensors not used by pixhawk 1 . I am going to my designated flying spot to see my results. I have composure. Just have not had these issues before but just trying to figure a solution. If it's going to remain this way, I will surely go back to pixhawk 1. At least I can use mission planner and diagnose things although with that many SATs I have never had a GPS lock out.

Rotorboy2.4gh · Dec 21, 2017

Also, I have worked as a beta tester in the past with Randy and Marco. I am just not familiar with this solo stuff just yet.

John Githens · Dec 21, 2017

My post (#20 in this thread) was intended for a general audience, particularly newer owners of a Solo-centric system.

Rotorboy2.4gh · Dec 21, 2017

After today if unsuccessful at the Flying location I am going to replace the Russian constellation with the Chinese constellation to see if that makes a significant difference.

David Boulanger · Dec 21, 2017

You can use mission planner. I think what's happening is you get a GPS drift from trees or buildings and the the Solo firmware determines the GPS position is not correct and gives you the lock problem.
All I can tell you is I have 5 mRo's and all work great as configured like they came.

Rotorboy2.4gh · Dec 21, 2017

Well, somewhat happy now. I'm out at my designated flying field and all went well with not one issue. So it appears solo is much more sensitive to surroundings of buildings and trees than the original pixhawk one. And I'm also understanding it solo does this so I can warn you that it's in fly mode so you know when to take over and not that it's just wtf. So, I am learning its limitations but still questioning how do sites can people use this around theaters and buildings with much success. Also would the GPS be on a mast serve any beneficial properties.

John Githens · Dec 21, 2017

John Githens said:
Before this thread bounces more among the usual related topics and instances of failures and proposed fixes, it might be a good idea to take some time to read the early sections of this post from Deep South Robotics, even though most of the post is about advanced navigation using satellite signals. In the field on some jobs where there is a higher risk of GNSS unlock, I will check the GPS Plan app on my iPhone to see which satellites could possibly be "seen", at that time, by any of the receivers on my drones. That app also quickly shows which times of the day are better than others for the maximum number of satellites in view from my location.

More frequently I will check UAV Forecast before going to a field location (and later on my iPhone with the app) to see the estimated Kp Index value and other forecast conditions. All of that operator prep is to gauge the risk that I may have to switch to non-GNSS ("manual") control in that location after a launch. As hinted in the Deep South post, the constellation of satellites being used in one time period may not be those that are used in the next time period. I have three mRo receivers (and one from Drotek), on masts, with the newer 3DR shield.

Even then there can be an unlock situation, as happened three times on one job while hovering low to the ground in deep woods on a hillside when the Kp Index value was Not Good. A quote attributed to Louis Pasteur: "Fate favors the prepared mind." Some practice and muscle memory on the control sticks helps too. If you don't have that experience yet, in many situations you can raise the throttle stick to go higher and give yourself time to regain your composure and decide what to do next. By that time your Solo may be up high enough to regain lock.

(comment for readers of this thread) Recently Tridge offered a link to this document, which helps to explain how "GPS lock" is first achieved (and hopefully re-achieved, as desired during a flight). That link can be found in this thread about the new SkyViper 2450GPS. The document is specific to the SkyViper 2450GPS, however much of it may apply to recent Arducopter code releases and associated hardware or system configuration options.

J0S0L0 · Dec 21, 2017

Rotorboy2.4gh said:
After today if unsuccessful at the Flying location I am going to replace the Russian constellation with the Chinese constellation to see if that makes a significant difference.

Let us know your satellite count and performance with the Chinese constellation..