3 ms·

Yeah, sure. But this is really not something that someone needs to reinvent, the basic 'algorithm' is even taught in private pilot classes. Did you ever had an

Yeah, sure. But this is really not something that someone needs to reinvent, the basic 'algorithm' is even taught in private pilot classes. Did you ever had any problems with GPSes in that region? (I got interested)

defrost 14y ago
We had no issues with either commercial GPS units nor with in house GPS units that recorded raw (from the satellite packets) apart from the usual ones (separation of the geoid from "sea level"). GPS near the pole gets more interesting as it pays to have your own translation (or one that you can trust) from raw sat packets directly to polar suitable planar mapping coords (as passing through anything [lat,lon] invokes the curse of singularity). We had issues with essentially every bit of commercial map related software that took GPS produced [lat,lon] pairs - eg: ARCGIS (1997) when handed a chain that crossed the data line failed on all derived calculations (enclosed area, transient velocity, instantaneous headings, etc). We were lucky in having fairly extensive in house software and no strict dependence on third party tools (eg: we didn't use Intrepid [1]) and having the ability to find all the points in the acquisition, processing, QC, presentation, and map production software that flipped out on sign inversion and recompiling to correct for those faults on the go. The interesting realisation was just how many "professional" tools failed to work in that part of the world; see Wingman4l7's comments for a typical "if it works in North America that's all that matters" attitude. [1] http://www.intrepid-geophysics.com/ig/index.php http://www.intrepid-geophysics.com/ig/index.php I suspect we have different definitions of hard; text based serial comms protocols can be difficult to parse if you lack a complete specification from the outset or if there are ambiguities. Hard is using Kalman filters on the fly to correct for the magnetic bias induced by a planes heading whilst correcting for diurnal magnetic pulsing and gathering multiple channels of radiometric data, watching ground separation radar and LIDAR, and doing differential GPS corrections against a base station and using temperature, pressure and humidity to estimate a standard air column density between craft & ground (for normalising gamma rays). I enjoyed your blog and wish you well in your pursuits.

defrost 14y ago

We had no issues with either commercial GPS units nor with in house GPS units that recorded raw (from the satellite packets) apart from the usual ones (separation of the geoid from "sea level"). GPS near the pole gets more interesting as it pays to have your own translation (or one that you can trust) from raw sat packets directly to polar suitable planar mapping coords (as passing through anything [lat,lon] invokes the curse of singularity). We had issues with essentially every bit of commercial map related software that took GPS produced [lat,lon] pairs - eg: ARCGIS (1997) when handed a chain that crossed the data line failed on all derived calculations (enclosed area, transient velocity, instantaneous headings, etc). We were lucky in having fairly extensive in house software and no strict dependence on third party tools (eg: we didn't use Intrepid [1]) and having the ability to find all the points in the acquisition, processing, QC, presentation, and map production software that flipped out on sign inversion and recompiling to correct for those faults on the go. The interesting realisation was just how many "professional" tools failed to work in that part of the world; see Wingman4l7's comments for a typical "if it works in North America that's all that matters" attitude. [1] http://www.intrepid-geophysics.com/ig/index.php http://www.intrepid-geophysics.com/ig/index.php I suspect we have different definitions of hard; text based serial comms protocols can be difficult to parse if you lack a complete specification from the outset or if there are ambiguities. Hard is using Kalman filters on the fly to correct for the magnetic bias induced by a planes heading whilst correcting for diurnal magnetic pulsing and gathering multiple channels of radiometric data, watching ground separation radar and LIDAR, and doing differential GPS corrections against a base station and using temperature, pressure and humidity to estimate a standard air column density between craft & ground (for normalising gamma rays). I enjoyed your blog and wish you well in your pursuits.