Long Period Heave Measurement System

Accurate measurements of ship heave are critical to evaluate the dynamic behavior of new vessels being developed for littoral and amphibious operations, as well as improving the accuracy of weapons targeting. Existing methods of heave measurement are based on double integration of measured acceleration to estimate vertical displacement. This approach is fundamentally limited by low frequency accelerometer drift and noise which, when integrated, is compounded to preclude accurate measurement of low frequency ship motion from longer period swell and tides. Creare is developing a novel Heave Measurement System designed to provide significantly more accurate measurements of vessel heave over long time periods. During Phase I, a prototype version of our system was constructed and demonstrated in the laboratory. This Phase II project involves construction and qualification of a fully integrated system that is ready for shipboard evaluation by the Navy.