Positioning a camera parallel to a plane using dynamic visual servoing

Visual servoing is generally based upon geometrical features. Recent developments were made in the way of a generalization of this approach to dynamic features. The idea is that velocity in the image can be measured without the constraint of having an a priori knowledge of the scene. In this paper, a control law to position a camera mounted on the end effector of a robot, in such a way the image plane becomes parallel to a planar object, is presented. A dynamic visual servoing approach is used by defining a control loop upon the second order spatial derivatives of the optical flow. A fixating task, which guarantees the object stays in the camera field of view is joined to the first one. Then, results obtained on a 6-DOF robot are laid out for the two studied tasks.