Multi-stage method of generating 3D civil site surveys

A method of creating a three dimensional model based on two dimensional images, comprising the steps of:

• acquiring a first set of images taken along a first radial path of capture at a first radial distance with respect to a common reference point at a physical structure, wherein each image of the first set of images is taken from a different location at the first radial distance along the first radial path of capture, and wherein each image of the first set of images is focused on the common reference point;
• acquiring a second set of images taken along a second radial path of capture at a second radial distance with respect to the common reference point, wherein each image of the second set of images is taken from a different location at the second radial distance along the second radial path of capture, and wherein the second radial distance is about twice as long the first radial distance and each image of the second set of images is focused on the common reference point;
• generating a first 3D model from the first set of images and a second 3D model from the second set of images based on a first plurality of feature points in each image of the first set of images, and a second plurality of feature points in each image of the second set of images, respectively;
• and
• merging the first 3D model from the first set of images with the second 3D model from the second set of images to generate a multi-scale 3D model using an iterative closest point algorithm or a generalized procrustes analysis, wherein the multi-scale 3D model comprises a merged set of feature points comprising a subset of the first plurality of feature points and a subset of the second plurality of feature points, and wherein the merged set of feature points comprises a merged density greater than a density of the first plurality of feature points and a density of the second plurality of feature points, wherein the merged density provides enhanced 3D image resolution for identifying unique characteristics of the physical structure at the common reference point, wherein the unique characteristics of the physical structure are perceptible to a size of about 0.1 mm.