Switched hybrid visual servoing using a target pose estimation without 3D structure information of an object

Abstract

This dissertation lays a hybrid visual servoing approach with a switched control law which consists of a position-based control law and an image-based control law. In order to obtain 3-D information between current state and the desired state, a new pose estimation method is proposed to overcome the limitations in the present visual servo systems. The proposed hybrid control law moves the camera equipped to a robot end-effector to the estimated target pose by a position-based control law and then positions it to the desired pose more accurately using an image-based control law. This switched visual servo system allows the camera path to follow a straight line and converges to the desired pose robust to camera calibration errors and pose estimation errors. In addition, a position-based control law containing the rotational control factor to gaze the object is newly introduced for solving the limited field of view problem. The proposed servoing approach solves chattering problems and shows the proper behavior, although the target pose is located out of the robot``s workspace. Moreover, we can find a stability bound to ensure the global asymptotic stability of the proposed servo system.