Vector Data Extraction from Forward-Looking Sonar Imagery for Hydrographic Survey and Hazard to Navigation Detection R. Glenn Wright Cheryl M. Zimmerman GMATEK, Inc., Annapolis, MD USA FarSounder, Inc. World Maritime University, Malmo, Sweden Warwick, RI USA
[email protected] /
[email protected] [email protected] Abstract— This paper describes research to determine the investigating its use as a means to navigate in uncharted and effectiveness of forward-looking sonar as a means to safely poorly charted areas are described along with their results navigate vessels in frontiers such as the Arctic and other regions illustrating the effectiveness of this technology and limitations that may be lacking recent or comprehensive hydrographic that may restrict its use. Conclusions regarding the viability of survey. Key elements of this investigation include the range at FL sonar to aid in vessel navigation are provided, along with which valid measurements may be taken, uncertainty in future directions in research likely to follow. measurement, confidence level of the measured value and resolution available to detect underwater hazards affixed to the II. CHARTING DEFICIENCIES bottom and suspended within the water column to provide time sufficient to enable the crew to take action to alter course and/or The deficiencies of hydrographic surveys in areas such as speed to avoid casualty. An additional factor involves examining the Arctic and the vast archipelagos of the Pacific Ocean have forward-looking sonar measurements as a means to survey been demonstrated through dramatic groundings of vessels. shallow sea bottom where hydrography data does not exist or is One example is the cruise chip M/V Clipper Adventurer that not accurate, potentially offering a valuable resource to ran aground on 27 August 2010 in Coronation Gulf, Nunavut supplement scarce national hydrographic office assets to in the Northwest Passage on an uncharted shelf in an area accomplish this task.