Abstract
The device consists of a camera which gives the HO an indirect view of a scene (real world); proprioceptive and exteroceptive sensors allowing the recreating of the 3D geometric database of an environment (virtual world). The virtual world is projected onto a video display terminal (VDT). Computer-generated and video images are superimposed. The man-machine interface functions deal mainly with on line building of graphic aids to improve perception, updating the geometric database of the robotic site, and video control of the robot. The superimposition of the real and virtual worlds is carried out through a calibration of the multisensor system. First, the sensing system and several methods used for modeling an environment's geometric database in telerobotics have been presented. The operator models unknown objects (of cylindrical or polyhedral pattern) using a video camera(VC) image and a range finder(RF). When the quality of images is poor, the range finder, which is mounted on a site and azimuth rotation turret, brings an indispensable complement by measures of depth. The improvement offered by the cooperation VC/RF has been shown for small depths (below 1.6m). In some particular cases we propose to achieve the fusion of multisensor redundant data, in order to reduce the uncertainty. Then the updating of environment's 3D geometric database in telerobotics by single camera view is presented. It concerns the pose determination of known objects using 2D clues obtained through video images. A two step algorithm is implemented and assessed. The first step is available in case of object large motion, it is a geometric algorithm, which doesn't use redundant data; .it provides a first estimate of the pose. The second step is available in case of object small motion. A linear approach is carried out to determine the pose. It allows the use of redundant data. so it improves the accuracy achieved after the first step.