Three-view uncalibrated visual servoing

A new uncalibrated visual servoing approach for motion control of 6-DOF manipulators is presented. Instead of image features, the elements of the scene-independent trifocal tensor of three views is used as features for visual servoing. These trifocal features depend only on the camera projection matrices and can be retrieved from point correspondences across the three views: initial, current, and desired. The Jacobian matrix that relates joint velocities and variations of the trifocal features is estimated online using least-squares. The visual servoing performance is evaluated for various easy and challenging motions, such as the translational motion along the view axis and the large rotation around the view axis. Simulations with a 6-DOF eye-in-hand manipulator show that the proposed uncalibrated approach rapidly converges in all cases.