1. A method for determining the angular position of an object, comprising the steps of: obtaining data representing an image of a surface area of the object, the image including a plurality of dots; determining a set of coordinates for each dot of the plurality of dots; selecting a predetermined number of dots of the plurality of dots; comparing the predetermined number of dots with a plurality of dots stored in a dot map; responsive to the comparing step, if the predetermined number of dots substantially match the plurality of dots stored in the dot map, selecting the predetermined number of dots; and forming a coordinate transformation matrix representing a transformation from a coordinate frame associated with a position of the predetermined number of dots at the surface of the object to a coordinate frame associated with a position of the image of the surface area of the object.