Evaluation of eye-vergence visual servoing by lateral frequency response

Abstract

Visual servoing towards moving target with hand-eye cameras fixed at a hand of a robot is inevitably affected by the hand's dynamical oscillations, therefore it is difficult to keep target's position always at the center of camera's view, because nonlinear dynamical effects of whole manipulator stand against tracking ability of the visual servoing. One possible solution to overcome this problem is that the visual servoing control of the hand and eye-vergence is separated independently, so that the camera can track the target to observe it at the center of camera images to enhance the tracking ability (trackability). In line with this tactics, the authors have developed an eye-vergence visual servoing control system to enhance the trackability. With several experiments, it has been shown that the trackability of the eye-vergence motion is superior to the one of hand-eye system since the eyes' motion can be quicker than the hand's motion.

Keywords

• visual servoing
• eye-vergence
• lateral frequency response
• quaternion