Autonomous driving system for reversing an articulated vehicle

Sammanfattning: Articulated vehicles are widely used in the economically vital cargo industry as they provide a greater maneuverability than their rigid counterparts. Hence, autonomous driving systems for articulated vehicles have become the subject of intense research in the robotic community. This thesis analyzes the reverse motion of an articulated vehicle, namely a tractor-trailer with one on-axle hitched semitrailer, and develops a full autonomous driving system that enables reverse parking in the presence of static obstacles. The motion controller used in the autonomous driving system is based on a two-level feedback control system, with a path stabilization controller in the first level and a hitch angle controller in the second level. The path planner used is a modified RRT planner where the Dubins path has been incorporated in order to enable the planning towards a goal pose rather than merely a goal region. The modifications made have resulted in several improvements, such as more accurate planning and higher computational efficiency. Using a 1:32 scale remote controlled tractor-trailer, and a Qualisys motion capture system for pose estimation, the autonomous driving system was successfully implemented and validated.