REAL-TIME VISUAL SERVOING USING CONTROLLED ILLUMINATION

A real-time visual servoing approach is applied to robotics tasks cons isting of the positioning of the end effector with respect to a priori known polyhedral objects. The vision appa ratus is constituted by a c ompact CCD camera rigidly coupled with two laser stripes mounted on th e wrist of a robot manipulator. The objective is to servo the robot en d effector at a constant position and orientation with respect to a kn own object in three-dimensional space in the field of view of the sens ory system. The approach is expressed in terms of sensor-based control (Samson et al. 1991) applied to visual servoing (Chaumette 1990; Urba n 1990). In the case of camera-light stripe coupling, the elementary v isual signals used for visual servoing are the points of discontinuity in the light stripes. The feasibility of the approach is demonstrated in a factory automation task consisting of the positioning of the end -effector tool over a vehicle battery. Both simulation and experimenta tion results are presented, proving the robustness and stability of th e algorithm.