Very accurate roll, pitch and heave measurements are essential to obtain good results when compensating multibeam sonars for vessel motion. Even small errors in roll and pitch can cause artificial “waves” on the resulting seafloor map. That is why the highest roll and pitch performance is needed for Hydrography.
When the multibeam sonar and motion sensor are mounted on a moving vessel it experiences horizontal accelerations, and especially during turns. The horizontal accelerations may degrade the roll & pitch measurements which in turn degrades the accuracy of the resulting seafloor map. The motion sensor can be aided by GNSS velocity and position measurements to minimize these errors.
NORSUB Marine MRUs are ideal for hydrographic applications because of its high accuracy roll & pitch measurements during periods of horizontal accelerations. This, in combination with the reliable and accurate heave measurements in irregular seas, makes it a perfect sensor for motion compensation of multibeam sonars and echosounders.