1. A method for determining a 3D position or 3D orientation of a physical object, comprising the steps of: creating in a computer a 3D data base of a designed object, said data base including a plurality of natural object features of the designed object; selecting one or more of said natural object features of said data base for subsequent use in determining the 3D position or 3D orientation of a physical object which corresponds to the designed object of the 3D data base; storing the selected object features of the 3D data base in a computer for subsequent use in determining the 3D position or orientation of said physical object; presenting the physical object for position or orientation determination; and determining the 3D position or 3D orientation of the physical object using the stored selected object features.