"Grids" were created because before easily accessible computing power was available the calculations required to work on the curved surface of the earth were cost (time) prohibitive, the calculations required to reduce slope distances to horizontal distances are relatively simple, so only some of the very oldest land descriptions in North America report slope distances.?ÿ
Most documents created by land surveyors in the 20'th and 21'st centuries report horizontal distances.
A continuing frustration for me is land surveors?ÿ instantace that we continue working on flat approximations of the earth's surface. We go on and on about low distortion projections without realizing that we have the technology at our fingertips to effortlessly recognize the earth is not flat and to remove the idea of a grid projection, a constant source of error, and confusion, once and for all.?ÿ
In other words, go to a geodetic system? Every bearing reported forward, back and mean? Perhaps on a township scale survey, but for most practical every day applications? Just seems a little extreme. I mean, we already do that whether we realize it or not with ever application of GPS technology, but as far as the practical applications of using cartesian coordinates to simplify every day applications, I just don't see the justification for what you are proposing. Enlighten me.
There is nobreason to report three differnt bearings. Mean is sufficient. How often do you break out the trig tables and calculate something by hand? When calculating with a data collector or on your computer there is no added complexity. I don't see anything impracticable about it.
Grid projections take your location data and "project" them in a distorted way onto a flat a surface. You are right that the location data is imperfect to begin with, but I don't see that as a justification to further distort your work and add another opportunity for error.?ÿ
I don't have any problems with the way we report elevations.
I don't see how this would be a problem for the A&E sector. What am I missing. The only effect I can see on them is that it would eliminate the mistake of designing on the grid.?ÿ
I wouldn't say that "designing on the grid" is a mistake.
For one thing, it's not the grid, it's ground - designers work on the ground. There's no way to both work geodetically and place ground values on a planset without applying some sort of transformation.
We do a lot of industrial building layout. In many of the regions we work in (and elevations we work at), the ground distance between two gridline intersections at opposite ends of a building will differ from the ellipsoid distance by several tenths or more.
SOP is to set a couple of critical intersections by total station from a single setup, and then let the construction crews set the intervening intersections by tape.
I'm trying to imagine a foundation crew pulling steel tape between two of those intersections, and looking at ellipsoid distances between gridlines trying to compute the ground equivalent.
Ellipsoid heights are part and parcel of geodetic-only work, and if we try to run with local elevations, again there has to be a transformation of some sort (typically the geoid or a project-specific vertical shift).
Even if we somehow find a way to avoid displaying ellipsoid heights on a planset,?ÿI would pay good money to watch even a top-notch construction team try to construct a basic commercial site with latitudes, longitudes, and ellipsoid distances.
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There is no reason to report three differnt bearings. Mean is sufficient.
Now I'm imagining a GIS analyst calculating records of survey for inclusion in the tax parcel database and punching their monitor because the figures aren't closing.
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