Communication

摘要

The visual servoing formalism provides a framework for achieving tasks in an active closed-loop fashion based on visual information. We consider a typical visual servoing ap proach that uses geometric information about image features for controlling the position and attitude of a camera and extend the applicability of this approach by using image motion infor mation. We present two different approaches to visual tasks that use motion information. The first uses the focus of expansion, which is related to the translational velocity of the camera. The second incorporates the parameters of the 2D affine motion model in control equations. Both of these approaches are il lustrated by means of a task of aligning the optical axis of the camera with the unknown direction of translational motion of the system on which it is mounted. Results of simulation experi ments and real experiments on a six degrees of freedom (DOF) robot with a camera on its end effector are presented.