TRIANGULATOR: Excel spreadsheets for converting relative bearings to XYZ coordinates, with applications to scaling photographs and orienting surfaces

Abstract

TRIANGULATOR comprises two Microsoft Excel spreadsheets for processing relative bearing data from an electronic total station. Program XYZ converts bearings to positions. It determines x, y, z coordinates of points from relative bearings from two base stations of known relative position. Program LINES uses the output of XYZ. It converts the x, y, z coordinates of three points into the equation of a plane, yielding strike and dip of that plane. Then it uses bearings from one base station to points on a cliff face, and calculates their x′, z′ coordinates for either direct measurement of features, or determination of the scale of a photograph. An example demonstrates the application of the program to scale the photograph of an exfoliation fracture.