Does the MRU measure surge and sway?

Yes, our MRUs measure surge and sway.

But note that as for heave, the measurements are about a zero mean average position. This means that for a ship that moved forward, it’s only the high frequency part of the surge motion that is measured by the MRU.

Accurate surge and sway measurements are dependant on accurate roll and pitch measurements, since small changes in roll and pitch influence the surge and sway measurements. That is why we recommend the 9000 series when surge and sway measurements are important. This can be for applications like 3D motion compensation.