Efficient seafloor classification and cable route design using an AUV

This paper aims to an efficient method for submarine cable route design using online seafloor classification from sonar scanlines conducted by an autonomous underwater vehicle (AUV). Currently, the cable route design works are carried out by experienced surveyors and engineers by hand. An online seafloor classification using an AUV with automated route planning method can improve the efficiency for submarine cable construction. Side scan sonar is a common device used for seafloor mapping and obstacles detection. In order to implement online seafloor classification and mapping, an AUV equipped with a side scan sonar is utilized to gather sonar scanlines. Scanlines are analyzed on the fly to classify sea floor using a probabilistic classifier based on Bayes' theorem and Naïve assumption to distinguish different types of seafloor. Based on the classified seafloor map, a probabilistic roadmap is constructed and an A* algorithm is applied to determine appropriate cable routes on the cable corridor. Seafloor classification, bathymetry, steep slope, angle of alter course, and cable length are the five factors of route design. A result of a cable route survey work between islands was demonstrated. The planned route using the proposed method is close in range to the one recommend by experts.