Trajectory generation by visual servoing

Abstract

Describes an approach to the problem of trajectory generation in a workspace by visual servoing. Visual servoing is based on an array of measurements taken from a set of images and used each time as an error function to compute a control vector. This is applied to the system (robot and camera) and enables it to move in order to reach a desired situation, at the end of the task, directly depicted in the image. The originality of this work is based on the concept of a time varying reference feature. Classically, in visual servoing, the reference features are static and the task to be achieved is similar to a positioning task. We define a specific task function which allows us to take into account the time varying aspect and we synthesize a new control law in the sensor space. This control law ensure the trajectory control in the workspace. Considering that any trajectories in workspace can be depicted as a combination of rotation and translation, we have tested our approach using these two elementary trajectories.