Résumé : This paper focuses on the way to achieve accurate visual servoing tasks when the shape of the object being observed as well as the desired image are unknown. More precisely, we want to control the camera orientation with respect to the tangent plane at a certain object point corresponding to the center of a region of interest. We want also to observe this point at the principal point to fulfill a fixation task. A 3D reconstruction phase must thus be performed during the camera motion. Our approach is then close to the structure-from-motion problem. The reconstruction phase is based on the measurement of the 2D motion in a region of interest and on the measurement of the camera velocity. Since the 2D motion depends on the shape of objects being observed, we introduce a unified motion model to cope both with planar and non-planar objects. However, since this model is only an approximation, we propose two approaches to enlarge its domain of validity. The first is based on active vision, coupled with a 3D reconstruction based on a continuous approach, and the second is based on statistical techniques of robust estimation, coupled with a 3D reconstruction based on a discrete approach. Theoretical and experimental results compare both approaches.