
NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Lehmann's Rules
From: Dave Walden
Date: 2007 Mar 16, 07:22 -0700
From: Dave Walden
Date: 2007 Mar 16, 07:22 -0700
According to my reading on Lehmann's rules, it is used in the situation where one has measured the relative angles between 3 points of known location. (Not individually relative to North, but only between each.) ((Sometimes called the three point problem or resectioning by surveyors.)) One then wants to plot the location where these relative bearings occur. One first assumes a postion and plots. The case involves systemmatic but non uniform bias induced by the incorrect location of the assummed postion. It does not invole random uncertainties. It is a geometric problem with a single (except for the degenerate case of all points lieing on the same circle) solution which can be found analytically. Lehmann's rule gives a graphical method of arriving at this unique solution. --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to NavList@fer3.com To unsubscribe, send email to NavList-unsubscribe@fer3.com -~----------~----~----~----~------~----~------~--~---