Image-based visual servoing for grasping unknown objects

In this paper we present an image-based visual servoing approach to the problem of grasping unknown objects by adopting visual vectors. A CCD camera mounted on the robot end-effector constructs the visually guided servo control system and the control scheme lends itself to task-level specification of manipulation goals by the visual vectors. The grasping task is to control the robot so that the vectors of the end-effector´s finger and of a target object´s grasp coincide. These vectors can be used to represent the work of a stable grasping of an object that is presented in an unstructured manner These visual vectors in image frame are obtained by analyzing the object´s image and projection. The objective of vector processing is to estimate the error between the finger and grasp vectors, and to control the robot in order to eliminate kinematic errors