Here is an interesting paper I came across that discusses using a digital terrain model to determine the SPR in a digital format. I think it is part of a PhD dissertation, but it is put together by someone with a good deal of survey experience.
Essentially there is a digital scanner that shoots the topography to be traversed, and a model created of the ground surface.
article
The paper also contains an interesting discussion of different methods used to measure courses. I just thought it was interesting reading, no great leaps forward for now.
Any thoughts?
Edited to make URL live.
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