This paper presents a new tracking system for autonomous underwater vehicles (AUVs) navigating in a close formation, based on computer vision and the use of active light markers. While acoustic localization can be very effective from medium to long distances, it is not so advantageous in short distances when the safety of the vehicles requires higher accuracy and update rates. The proposed system allows the estimation of the pose of a target vehicle at short ranges, with high accuracy and execution speed. To extend the field of view, an omnidirectional camera is used. This camera provides a full coverage of the lower hemisphere and enables the concurrent tracking of multiple vehicles in different positions. The system was evaluated in real sea conditions by tracking vehicles in mapping missions, where it demonstrated robust operation during extended periods of time

This research was sponsored by the MORPH EU FP7-Project under Grant Agreement FP7-ICT-2011-7-288704, the Spanish National Project OMNIUS (Lightweight robot for omnidirectional underwater surveying and telepresence) under Agreement CTM2013-46718-R, the ROBOCADEMY (European Academy for Marine and Underwater Robotics) EU FP7-Project under Grant Agreement 608096, the Generalitat de Catalunya through the ACCIO (Agència per a la competitivitat de l’empresa de la Generalitat de Catalunya)/TecnioSpring program (TECSPR14-1-0050), with the support of “la Secretaria d’Universitats i Recerca del Departament d’Economia i Coneixement de la Generalitat de Catalunya”