Editing Dynamic positioning (section)

== Scope ==
A ship can be considered to have six [[Degrees of freedom (engineering)|degrees of freedom]] in its motion, i.e., it can translate and rotate on three perpendicular axes.

Three of these involve [[translation (physics)|translation]]:
*surge (longitudinal axis, forward/astern)
*sway (lateral axis, starboard/port)
*heave (vertical axis, up/down)

and the other three [[Yaw, pitch, and roll|rotation]]:
*roll (rotation about longitudinal axis)
*pitch (rotation about lateral axis)
*yaw (rotation about vertical axis)

Dynamic positioning is concerned primarily with control of the ship in the [[horizontal plane]], i.e. the translation along the two horizontal axes (surge and sway) and rotation on the vertical axis (yaw).