A new approach for robotic visual tracking and servoing is discussed. Deformable active models are introduced as a powerful means for tracking a moving rigid object (an eye-in-hand robot arm is used). Deformable models imitate, in real-time, the dynamic behavior of elastic structures. These computer-generated models are designed to capture the silhouette of rigid objects with well defined boundaries in terms of image gradient. By means of an eye-in-hand robot arm configuration, the desired motion of the end-effector is computed with the objective of keeping the target's position and shape invariant with respect to the camera frame. Experimental results are presented for the tracking of a rigid object moving in the three-dimensional space.>

Presents a coherent approach for visual servoing tasks that consists of following the contours of unknown objects using a hand-eye robotic system. The motion of the contour relative to the camera sensor is estimated in real-time by processing the measured optical flow of a set of relevant feature points. The desired motion of the end-effector is then computed to minimize the displacements of the feature points with respect to a reference configuration in the image. Control schemes are used in order to stabilize the robot and enhance tracking performances. The authors illustrate the approach by experimental results acquired with a real-time environment, where their CMU-Direct-Drive Arm II follows the boundaries of motionless objects positioned in a plane parallel to the image plane. Three degrees of freedom of planar motions are thus servoed to perform the contour-following task.

This paper presents a new approach for visual tracking and servoing in robotics. We introduce deformable active models as a powerful means for tracking a rigid object in movement within the manipulator's workspace. Deformable models imitate, in real-time, the dynamic behavior of elastic structures. These computer-generated models are designed to capture the silhouette of rigid objects with well-defined boundaries, in terms of image gradient. By means of an eye-in-hand robot arm configuration, the desired motion of the end-effector is computed with the objective of keeping the target's position and shape invariant with respect to the camera frame. Optimal estimation and control techniques (ZQG regulator) have been successfully implemented in order to deal with noisy measurements provided by our vision sensor. Experimental results are presented for the tracking of a rigid object moving in a plane parallel to the image plane (three degree-of-freedom visual servoing). The experiments performed in a real-time environment show the effectiveness and robustness of the proposed method for servoing tasks based on visnal feedback control.