Dipartimento di Ingegneria informatica, automatica e gestionale

In this paper, we present a sonar-based navigation system, designed to deploy a fleet of autonomous mobile platforms at a reasonable cost. In educational and hobbyist contexts, a large number of robots is required. By means of classical navigation approaches, every robot should be provided with accurate vision or range sensors. This limits the maximum number of robots in the fleet, due to the unaffordable cost of these sensors. In contrast to that, our system requires a single platform equipped with a higher quality sensor, used to perform calibration and mapping tasks. The rest of the fleet, able to localize and navigate, is equipped solely with low-cost sonars, providing a notable reduction in the overall cost. We achieve this task by presenting a novel calibration procedure to estimate the sonars extrinsic and adapting a classical monte-carlo localization algorithm to the sonar model, focusing on efficiency. We release an open source implementation of the system to the community.