Terrain-Aware Path Guided Mobile Robot Teleoperation in Virtual and Real Space

This paper concerns the development of a force feedback enhanced teleoperation system for outdoor robotic vehicles navigating in rough terrain where true-colour 3D virtual world models of the working environment, created from laser and colour image scans collected offline, can be explored by walk-throughs both before and during the robot navigation mission itself. In other words, the physical mission planned can be partially rehearsed in cyberspace. Further, during a mission, the location and orientation of the vehicle are continually determined and global collision-free paths to selected goal locations made available as advice to the operator, who can follow or ignore such advice at will. Live (real-time) 3D laser range data also provides an up-to-date scan of the volume immediately surrounding the vehicle as it moves so that dynamic obstacles can be avoided. Local terrain-roughness is taken into account in the provision of local collision-free paths, the sub-goals of which, are operator determined. This live range data is matched with the pre-scanned range data to calculate the accurate robot vehicle localisation (position and orientation) which is provided continuously during the navigation mission. A force feedback 3D joystick reflects terrain roughness as a vibration in one axis and the other two axes are used to provide a 2D force to attract the operator towards following the local optimal collision-free path, but this attraction can be easily overridden by the operator. The instrumentation and methodologies used are presented, together with some preliminary experimental results.