1. An imaging robot for imaging a surface, comprising: a positioning system including a support and a digital camera mounted on the support for imaging the surface; wherein the positioning system comprises mutually orthogonal first, second, and third linear translators coupled to the support, for positioning the digital camera in front of the surface at a plurality of shooting positions forming a two-dimensional grid of positions spaced from the surface at a substantially same shooting distance; wherein the first translator comprises a horizontal base, a driven wheel mounted to the base, for rolling on a substantially horizontal floor, and a pair of rollers mounted to the base, for moving the base horizontally with respect to gravity, along the surface to be imaged; wherein the second translator comprises a linear translation stage extending vertically from the base, comprising a first portion mounted to the base, and a second portion translatable relative to the first portion, vertically with respect to gravity, and along the surface to be imaged; wherein the third translator comprises a linear translation stage having a first portion and a second portion translatable relative to the first portion, horizontally with respect to gravity, towards and away from the surface being imaged, wherein the first portion of the third translator is mounted to the second portion of the second translator; and a tilt stage coupled to the support, for orienting an optical axis of the digital camera perpendicular to the surface being imaged, wherein the tilt stage comprises first and second portions movable angularly with respect to each other, the first portion of the tilt stage being mounted to the second portion of the third translator, wherein the second portion of the tilt stage is mounted to the support; an illuminator for selective illumination of a portion of the surface being imaged by the digital camera; and a controller for providing control signals to the first, the second, and the third translators for positioning the digital camera, wherein the controller is operationally coupled to the digital camera for causing the digital camera to capture a component image of a portion of the surface at each of the shooting positions.