Detailed information about the subsurface section of an iceberg is of high value to researchers and offshore operators, and can be used to create hydrodynamic models of icebergs, calculate impact loads, and to forecast iceberg drift. However, since the iceberg will translate and rotate when affected by water currents, mapping the underwater geometry of an iceberg is non-trivial. This paper will describe an algorithm for automatic detection and mapping of drifting icebergs using autonomous underwater vehicles (AUVs). Using an upwards-looking multibeam echosounder (MBE), the AUV monitors a given area in detection mode. When exceeding a specified ice draft threshold, the AUV will enter mapping mode. The AUV will search for the edge of the iceberg, and follow the edge once detected. Through this paper, the detection procedure based on measurements from a MBE is presented, and the algorithm for mapping the iceberg while the iceberg is drifting is outlined. The results will be presented in a simulation study, which will show the effectiveness of the mapping procedure for a simulated iceberg drifting with constant, linear speed. The AUV will perform a complete circumnavigation of the iceberg, before completing the mapping procedure, and continuing its pre-defined mission.
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