“…This study focuses on the registration techniques that allow alignment of real and virtual worlds using images acquired in real-time by moving cameras. In the related computer vision literature geometric primitives considered for the estimation are often points [7], [3], [11], contours or points on the contours [10], [2], [5], segments, straight lines, conics, cylindrical objects, or a combination of these different features [13]. Another important issue is the registration problem.…”