Image-based Visual Servoing of a Real Robot Using a Quaternion Formulation

In this paper we present the results from our visual servoing system for a real industrial robot. In contrast to other visual servoing system in the literature, the one presented here, which was derived from [4], uses a quaternion representation of the rotation instead of the more common matrix representation. By doing so, the proposed system avoids potential singularities introduced by the rotational matrix representation. After performing exhaustive tests in a simulated environment, our controller was applied to a Kawasaki UX150. In the case of simulation, the movement of the camera and the image processing were performed using Matlab-Simulink, which allowed us to test the controller regardless of the mechanism in which the camera was moved and the underlying controller that was needed for this movement. In the case of the real robot, the controller was tested initially using another simulation program provided by Kawasaki Japan and later with the real Kawasaki robot. The setup for testing and the results for all three cases above are presented here, but for more details on the simulations, the reader is encouraged to check [8].