Collision-Free and Continuous-Curvature Path Planning for Car-Like Robots

Abstract

: This paper presents a set of paths, called bi-elementary paths. These paths are smooth and feasible for a car-like robot (i.e. their tangent direction is continuous and they respect a minimum turning radius constraint), and they can be followed by a real vehicle without stopping (i.e. they have a continuous curvature profile) --- which is not the case of Dubins' curves. These paths are composed of arcs of clothoid (a clothoid is a curve whose curvature is a linear function of its arc length), and are used to define a simplified, i.e. non complete, planner. This simplified planner is, in turn, used in two global planning schemes, namely the Ariadne's Clew algorithm and the Probabilistic Path Planning. This paper proves an important property of the bi-elementary paths, from which the completeness of the two global planners is deduced. Keywords --- mobile-robot, path-planning, non-holonomic-system, continuous-curvature paths, clothoids, global planner, completeness. Acknowledgements ...