Well structured robot positioning control strategy for position based visual servoing

In this paper we study a 3D visual servoing system composed by a robot manipulator, a CCD camera mounted on the end effector of the robot and a specific hardware. The use of computer vision as feedback transducer strongly affects the closed loop dynamics of the overall system, so that a visual controller is required for achieving fast response and high control accuracy. Due to the long time delay to generate the control signal, it is necessary to carefully select the visual controller. The objective of this work is to present a well structured design of efficient controllers to keep a desired relative 3D position between the object and the camera. Besides an experimental setup has been built and used to evaluate the performance of the position based dynamic look and move system. Several results relative to different type of controller are presented. These results demonstrate the possibility of getting competitive results in real time performance with respect to more closed solutions shown in other works, while maintaining the advantage of easily system adaptability.