Automatic Detection of Underwater Chain Links using a Forward-Looking Sonar

Underwater chain cleaning and inspection tasks are costly and time consuming operations that must be performed periodically to guarantee the safety of the moorings. We propose a framework towards an efficient and costeffective solution by using an autonomous underwater vehicle equipped with a forwar...

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Detalles Bibliográficos
Autores: Hurtós Vilarnau, Natàlia, Palomeras Rovira, Narcís, Nagappa, Sharad, Salvi, Joaquim
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2013
País:España
Institución:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:10256/11629
Acceso en línea:http://hdl.handle.net/10256/11629
Access Level:acceso embargado
Palabra clave:Robots submarins
Underwater robots
Vehicles submergibles
Submersibles
Sonar (Navegació)
Descripción
Sumario:Underwater chain cleaning and inspection tasks are costly and time consuming operations that must be performed periodically to guarantee the safety of the moorings. We propose a framework towards an efficient and costeffective solution by using an autonomous underwater vehicle equipped with a forward-looking sonar. As a first step, we tackle the problem of individual chain link detection from the challenging forward-looking sonar data. To cope with occlusions and intensity variations due to viewpoint changes, the recognition problem is addressed as local pattern matching of the different link parts. We exploit the high frame-rate of the sonar to improve, by registration, the signal-to-noise ratio of the individual sonar frames and to cluster the local detections over time to increase robustness. Experiments with sonar images of a real chain are reported, showing a high percentage of correct link detections with good accuracy while potentially keeping real-time capabilities