Just watched the video uplinks from unConference 2017 and would like to comment generally on GNSS and coordinate systems. As a spatial analyst modelling the real wold it is useful to be able to operate in the same coordinate system for an entire project and not have to project between system throughout the projec . I was really impressed with the presentations and presenters at the unConference, but people gave the impression that survey grade GNSS is not a priority for Mission Planner and Pixhawk. As someone who is having survey grade GNSS integrated into my multirotors, can I suggest that including a third part SDK into Mission Planner to handle coordinate systems as a fast track solution. Something like GeoCalc SDK from Blue Marble Geographics could provide survey grade coordinate transformations as well (for us Aussies) include AHD as a height datum utilising the current Ausgeoid would be a massive upgrade/enhancement to mission Planner. I would pay to have Mission Planner with GeoCalc capabilities - plan, undertake and record missions in MGA94 with Australian Height Datum. This could be implemented into a ‘Commercial’ version of Mission Planner if necessary and charge to cover costs of GeoCalc plus implementation.
Any thoughts about implementing survey coordinate systems and datums re Mission Planner?
With the wide spread adoption of RTK it can be assumed that people are expecting the more accurate results that RTK intimates.
This in turn is interesting to the professional spacial analysts like @Scriffo, and all manner of survey professionals and people wanting to do survey grade spacial modelling.
The multitude of different co-ordinate systems is beyond my scope of understanding and I am sure the Dev’s have a bit of a learning curve to climb on this, but I can see that this must be the next step beyond simple RTK integration to keep the Ardupilot suite at the leading edge of autopilots.
I am sure @Scriffo is willing to lend his expertise in this area if asked.
How does the Dev community feel about adding this to the Ardupilot/GCS suite?
The current issue is that MP under the hood is just converting the entered cords into lat/lng/alt. as this is how the autopilot talks.
yes I can add mga/ahd. but all this is really doing is converting it back to lat/lng/alt using wgs84
so the question is. is that enough? oh and everything the autopilot records would be in wgs84 as well.
So, in reality, it is meaningless implementing RTK on Ardupilot for sub cm accuracy when the base co-ordinate system can be out by 20m.
This GNSS accuracy push, blended multiple GPS’s, RTK integration, is interesting to those that use these levels of accuracy but on closer examination the Ardupilot/GCS system does not make the grade due to the vagaries of mapping a non spherical and uneven planet.
Shouldn’t we be including a disclaimer with Ardupilot?
“Not suitable for accurate survey work, hobby grade only”?
I’m not sure why you think it will be 20m out. the gps is outputting lat/lng/alt in wgs at high accuracy. and the autopilot is using that.
lat/lng/alt does not make it inaccurate at all. its just a coord transformation. converting lat/lng/alt in wgs to MGA is again just a transformation.
where are you getting your 20m’s from?
if you wanted to be 100% accurate you should be using ECEF not lat/lng/alt / MGA/ UTM. as this is the coord system GPS operates in.