Robust tracking of longitudinal objects lying on the sea floor with an AUV equipped of a scanning sonar

The paper considers the problem of using an autonomous underwater platform equipped with a scanning profiler sonar to track elongated objects lying on the sea floor, e.g., pipelines. The algorithm presented assumes the existence of features that enable the discrimination between sonar profiles received from the tracked object and those received from the background sea bottom. The algorithm does not require explicit classification of the profiles received (as coming from the tracked object or from the sea bottom), and does not rely on reconstruction of the geometry of the surface of the tracked object (allowing tracking of proud or partially buried objects). Simulation results illustrate the performance of the algorithm presented, as well as the effect of departures from the assumed geometric and reflectivity characteristics of the actual tracking configuration. Results of processing of real sonar profiles obtained at sea with a man-made object of cylindrical geometry are presented, demonstrating the appropriateness of the approach proposed