ABSTRACT
This paper overviews the probabilistic roadmap ap proaches to path planning whose surprising practical performances attract today an increasing interest. We first comment on the configuration space topology in duced by the methods used to steer a mechanical sys tem. Topology induces the combinatorial complexity of the roadmaps tending to capture both coverage and con nectivity of the collision-free space. Then we introduce the notion of optimal coverage and we provide a paper probabilistic scheme in order to compute what we called visibility roadmaps [26]. Reading notes conclude on re cent results tending to better understand the behavior of these probabilistic path planning algorithms.