A two phase RGB-D visual servoing controller

This paper presents a novel visual servoing system that is simple, robust, and relatively fast. Our system utilizes depth information available from an RGB-D Microsoft Kinect, rather than a stereo camera that is known to fail in poorly textured environments. The technique is based on a two-phase controller. The first phase provides a coarse image plane alignment with a target image using image saliencies for registration. The second phase relies on a depth-map-error-minimization to further reduce the position error and precisely situate the robot. Based on the magnitude of error between actual and desired position the system activates one or both phases sequentially to successfully servo the robot to its destination. Experiments demonstrate the success of the proposed system for both large and small initial position errors.