Visual feedback in camera motion generation: experimental results

Abstract

We propose several results about trajectory generation by visual servoing. The approach consists of defining a specific task function which allows one to take into account the time varying aspect of the reference feature and to synthesize a control law in the sensor space. This control law ensures the trajectory control in the image space and reduces the tracking error. Under specific conditions, the trajectory of the camera can be ensured in the robot workspace. The main goal of this work is to demonstrate the effectiveness of this approach through experimental results. In the experiments, we used a Cartesian robot and a real time vision system. A CCD camera was mounted on the end effector of the robot. We present two types of trajectory. The first one is a helical trajectory parallel to a cube side. The second one involves passing around a cube. This latter is built by linking several elementary trajectories (rotation and translation).