Conceptual Study of a USV for theSwedish Navy

This thesis is an initial conceptual study of an unmanned surface vehicle (USV) for the Swedish Navy. The purpose is to highlight challenges and possibilities connected to unmanning a vessel and to suggest one specific concept. Generating one concept meant weighing characteristics of different hull types against one another to derive a valuable compromise. The generated concept includes a feature of longitudinal bulkheads separating an inner, dry volume from outer ballast volumes. The latter fill with seawater at low velocities, causing the hull to partly submerge which in turn decreases signature and increases ballistic protection within the semi-submerged speed range. The!concept!measures 6.2 by 2.3 meters, weigh, approximately 1800 kg and may reach a calm water top speed of 44 knots. Investigating needs and potentials of an unmanned vessel within the Swedish Navy resulted in a set of requirements, including the possibility to arm the USV. This study investigates feasibility of carrying the SAAB Trackfire remote weapon platform aboard. Development of the initial USV concept was focused on aspects of naval architecture, including the making of a!general arrangement, evaluating materials, a structural design, stability and power need analysis. Although unmanned vessels are likely to be subject to lessened structural safety factors as opposed to manned, scantling determination is based on DNV rules for classification of High Speed, Light Craft and Naval Surface Craft.